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I-SEM Rules

Trading and Settlement Code

Calculation of Payments and Charges

Updated Interim Legal Draft

0214/067/2016

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A. CALCULATION OF PAYMENTS AND CHARGES

A.1 INTRODUCTION

A.1.1 Purpose of this ChapterA.1.1.1 This chapter specifies how the Market Operator shall calculate the charges

and payments for settlement of the Balancing Market and Imbalances.

A.1.2 Settlement Charges and Payments for Generator UnitsA.1.2.1 The Market Operator shall calculate the following charges and payments for

each Generator Unit for the relevant period, in accordance with the timetable in section [ ]:

(a) CIMBuγ, the Imbalance Component Payment or Charge calculated in accordance with section A.5;

(b) CPREMIUMuγ, the Premium Component Payment calculated in accordance with section A.6;

(c) CDISCOUNTuγ, the Discount Component Payment calculated in accordance with section A.6;

(d) CAOOPOuγ, the Offer Price Only Accepted Offer Payment or Charge calculated in accordance with section A.7;

(e) CABBPOuγ, the Bid Price Only Accepted Bid Payment or Charge calculated in accordance with section A.7;

(f) CCURLuγ, the Curtailment Charge calculated in accordance with section A.8;

(g) CUNIMBuγ, the Uninstructed Imbalance Charge calculated in accordance with section A.9;

(h) CIIuγ, the Information Imbalance Charge calculated in accordance with section A.10;

[(i)] CFCukCFCub, the Fixed Cost Payment or Charge calculated in accordance with section A.11; and

(i)[(j)] CTESTuγ, the Testing Charge calculated in accordance with section A.13.

A.1.3 Settlement Charges and Payments for Supplier UnitsA.1.3.1 The Market Operator shall calculate the following charges and payments for

each Supplier Unit for the relevant period, in accordance with the timetable in section [ ]:

(a) CIMBvγ, the Imbalance Component Payment or Charge calculated in accordance with section A.5;

(b) CIMPvγ, the Imperfections Charge calculated in accordance with section A.12;

(c) CREVvγ, the Residual Error Volume Charge calculated in accordance with section A.14; and

(d) CCAvγ, the Currency Adjustment Payment or Charge calculated in accordance with section A.15.

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A.2 DATA SOURCES, CONVENTIONS AND DEFINITIONS

Explanatory notes

To define the source of each variable and parameter required for the purposes of settlement calculations;

To define calculations the Market Operator needs to carry out on data which is used in multiple components of calculations throughout this section.

To define conventions required for the understanding of this section. These may at a future time be moved to a general interpretations section for the code, rather than a specific section for this aspect of the rules.

A.2.1 DefinitionsA.2.1.1 For each Imbalance Pricing Period, φ, and each Imbalance Settlement

Period, γ, as applicable for the relevant process, for the purposes of this Code the Bid Offer Acceptance subscript, o, resets to zero so that the first Bid Offer Acceptance in the period has a subscript value of o = 1.

A.2.1.2 The Market Operator shall set the value of a variable at zero where this Code states that a provision does not apply to a unit, and where the variable which is the result of that provision is to be used in a later process for that unit.

[A.2.1.3] The Market Operator shall determine whether a Pumped Storage Generator Unit, u, is in Pumping Mode for the purposes of [the calculations in] this Code as follows:

(a) If the value of a Pumped Storage Unit’s Dispatch Quantity (qDuoγ(t)) at all times within an Imbalance Settlement Period, γ, is entirely positive (i.e. in the generating range of the unit’s output), then the unit is deemed to be in Generating Mode for the entirety of that Imbalance Settlement Period;

(b) If the value of a Pumped Storage Unit’s Dispatch Quantity (qDuoγ(t)) at any time within an Imbalance Settlement Period, γ, is negative (i.e. in the pumping range of the unit’s output), then the unit is deemed to be in Pumping Mode for the entirety of that Imbalance Settlement Period.

A.2.1.3[A.2.1.4] An “incremental action” (“Inc”) is a System Operator action intended to increase the power (MW) or energy (MWh) being sent out into the system, or decrease the power or energy being taken from the system. Inc power or energy quantities are positive, resulting from the Dispatch Quantity being higher than the Physical Notification Quantity for a unit at any point in time. Incremental actions are represented in settlement through Accepted Offer Quantities.

A.2.1.4[A.2.1.5] A decremental action (“Dec”) is a System Operator action intended to decrease the power (MW) or energy (MWh) being sent out into the system, or increase the power or energy being taken from the system. Dec power or energy quantities are negative, resulting from the Dispatch Quantity being lower than the Physical Notification Quantity for a unit at any point in time. Decremental actions are represented in settlement through Accepted Bid Quantities.

A.2.1.5[A.2.1.6] Variables for power (expressed as MW) quantities begin with a lower case “q”, while variables for energy (expressed as MWh) quantities begin with an upper case “Q”.

[A.2.1.7] A Scheduling Agent is the entity or entities with the task of providing details of ex-ante market schedules Contracted Quantities from market participants to

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TSOs, or where applicable third parties, in accordance with [Guideline on Electricity Transmission System Operation].

A.2.1.6[A.2.1.8] A variable which is a function of time may have a different value at each time within an Imbalance Settlement Period, γ, or Trading Period, h, rather than a single fixed value defined for all times within an Imbalance Settlement Period, γ, or Trading Period, h. Such variables are represented with the inclusion of the notation ‘(t)’ at the end of the variable term.

A.2.1.7[A.2.1.9] The Interconnector Data Submission Point is the notional point at which the Interconnector Residual Capacity Units and Interconnector Error Units are deemed to be joined to the SEM and at which relevant metered values are collected, prior to Loss-Adjustment and in respect of the transmission of electricity across an Interconnector into SEM.

A.2.2 Sign ConventionsA.2.2.1 All values that relate to power (MW) or energy (MWh) being input into the

SEM are positive values. All values that relate to power (MW) or energy (MWh) being taken from the SEM are negative values.

A.2.2.2 All values that relate to amounts (in € or £) due to a Participant or in respect of a unit from the Market Operator are to be treated for the purposes of the calculations set out in this Code as having positive values. All values that relate to amounts (in € or £) due from a Participant or in respect of a unit to the Market Operator are to be treated for the purposes of the calculations set out in this Code as having negative values.

A.2.2.3 All values for power (MW) or energy (MWh) that relate to imports into the SEM in relation to an Interconnector, Interconnector Residual Capacity Units or Interconnector Error Unit shall be treated for the purposes of the calculations set out in this Code as having positive or zero values. All values for power (MW) or energy (MWh) that relate to exports from the SEM in relation to an Interconnector, an Interconnector Residual Capacity Units or an Interconnector Error Unit shall be treated for the purposes of the calculations set out in this Code as having negative or zero values.

A.2.2.4 All values for power (MW), ramp rates (MW/min) or energy (MWh) and which are not Loss-Adjusted in relation to an Interconnector, Interconnector Residual Capacity Units or Interconnector Error Units shall be those applicable at the Interconnector Data Submission Point.

A.2.3 Ex-Ante Market Data[A.2.3.1] Each Scheduling Agent for a Participant shall submit to the Market Operator

[for each Participant][details of the Contracted Quantities from the ex-ante markets (the Day-ahead Trade Quantities and Intraday Trade Quantities, qQTDAxuh, QqTIDxuh, QqTDAxvh and QqTIDxvh), the durations relevant to the trades (Day-ahead Trade Duration and Intraday Trade Duration, DTDAx and DTIDx), and the prices relevant to those quantities (the Day-ahead Trade Price and Intraday Trade Price, PTDAxuh, PTIDxuh, PTDAxvh and PTIDxvh), for each Generator Unit, u, and each Supplier Unit, v, , for each Trade, x, in each Period, h, in this context meaning the Day-ahead and Intraday Trading Periods.

A.2.3.1[A.2.3.2] On submission of Contracted Quantities from the ex-ante markets, the Market Operator will carry out a Credit Assessment of each Participant applying the rules set out in [sections A.15, A.16 and A.17 of Chapter on Financial Settlement].

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A.2.3.2 If the Market Operator determines that the Contracted Quantities submitted for a Participant under paragraph A.2.3.1 would result in the Participant’s Required Credit Cover exceeding its Posted Credit Cover, the submission of such Contracted Quantities will be refused by the Market Operator according to the following rules:

(a) Where only one Contracted Quantity has been submitted for a Participant, the Contracted Quantity submitted will be refused;

(b) Where more than one Contracted Quantity has been submitted for a Participant’s Units for the same period:

(i) the smallest Contracted Quantity will be refused; and

(ii) if the Market Operator determines that the remaining Contracted Quantities still result in the Participant’s Required Credit Cover exceeding its Posted Credit Cover, then the next smallest Contracted Quantity will be refused, and so on, until such time as the remaining Contracted Quantities would not result in the Participant’s Required Credit Cover exceeding its Posted Credit Cover;

(c) In applying sub-paragraph (b), where more than one of the Contracted Quantities submitted for a Participant’s Units for the same period are equal, the Market Operator will choose which of the two Contracted Quantities to refuse on a random basis; and

(d) the Market Operator may only refuse entire Contracted Quantities and may not adjust submissions.

2.3.3 The refusal of a Contract Notification by the Scheduling Agent does not affect any submitted Physical Notification by the Participant to the System Operator.

A.2.3.4 If the Market Operator has not received a submission under paragraph A.2.3.1 for a Participant’s Unit which applies to an Imbalance Settlement Period by the time the Market Operator is required to calculate the payments and charges in accordance with this Code for that period, Tthe value of the Ex-Ante Quantity (QEXuγ and QEXvγ) for each the relevant Generator Unit, u, and each or Supplier Unit, v, in each Imbalance Settlement Period, γ, shall be deemed to be zero. if the Market Operator has not received values of the Contracted Quantities from the ex-ante markets by the time it is required to carry out the Settlement calculations..

A.2.3.5 If the Market Operator refuses a Contracted Quantity under paragraph A.2.3.3, the value of the relevant Contracted Quantity (the Day-ahead Trade Quantity and Intraday Trade Quantity, qTDAxuh, qTIDxuh, qTDAxvh and qTIDxvh) for the relevant Generator Unit, u, or Supplier Unit, v, shall be deemed to be zero.

[A.2.3.3] The Scheduling Agent for each Interconnector shall submit to the Market Operator the final Intraday Interconnector Schedule Quantities (qQICSIDlh) for that Interconnector, l, relevant to the calculation of Charges and Payments, in each Period, h, in this context meaning the Intraday Trading Period.

A.2.4 Physical Notification DataA.2.4.1 For the purposes of calculating the Information Imbalance Charge in

accordance with section A.10, the PN Submission Period, β, means each half-hour period between 13:30 TD-1 and the Gate Closure time for an

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Imbalance Settlement Period during which a Participant may submit Physical Notification Data in respect of that Imbalance Settlement Period.

A.2.4.2 For all purposes not covered under paragraph A.2.4.1, the subscript, β, refers to the time Physical Notification Data or Commercial Offer Data, as the case may be, was Accepted.

A.2.4.3 The value of the Final Physical Notification Quantity (qFPNuh(t)) for each Generator Unit, u, which has Priority Dispatch, and which is non-dispatchable, shall at all times in Period, h, be deemed to be equal to the Outturn Availability Quantity (qAVAILOuh(t)) of the unit.

A.2.4.4 The Market Operator shall derive the Physical Notification Quantity (QPNuβγ) for Generator Unit, u, in PN Submission Period, β, for Imbalance Settlement Period, γ, by integrating the associated function of time Physical Notification Quantity (qPNuβγ(t)) from the Accepted Physical Notification Data prevailing at the end of that PN Submission Period, with respect to time across the Imbalance Settlement Period.

A.2.4.5 The Market Operator shall derive the Final Physical Notification Quantity (QFPNuγ) for Generator Unit, u, in Imbalance Settlement Period, γ, by integrating the associated function of time Final Physical Notification Quantity (qFPNuγ(t)), determined in accordance with [section in Data Submission], with respect to time across the Imbalance Settlement Period.

[A.2.4.6] The Market Operator shall derive the Final Physical Notification Quantity (QFPNlγ) for Interconnector, l, in Imbalance Settlement Period, γ, by integrating the associated function of time Final Physical Notification Quantity (qFPNlγ(t)), determined in accordance with [section in Data Submission]paragraph A.2.5.4, with respect to time across the Imbalance Settlement Period.

A.2.5 Dispatch DataA.2.5.1 Each System Operator shall submit to the Market Operator the Dispatch

Instructions in respect of each Generator Unit that is registered within its Jurisdiction, and may submit an associated Ramp Rate and curtailment flag for each Dispatch Instruction.

A.2.5.2 Each System Operator shall submit information referred to in paragraph A.2.5.1 to the Market Operator in accordance with [Appendix K “Market Data Transactions”], based on Outturn Data, and the values submitted shall be net of Unit Load.

A.2.5.3 Except as provided in paragraph A.2.5.6(a), the Market Operator shall derive the value of the Dispatch Quantity (qDuoh(t)) for each Generator Unit, u, for each Bid Offer Acceptance, o, in Period, h, in accordance with [Appendix O “Instruction Profiling Calculations”], from the Dispatch Instructions submitted by the relevant System Operator.

Explanatory Note

The following two paragraphs may need to be moved to a different section of the code – this section relates to the settlement calculations, while the paragraphs below relate to trading activities.

A.2.5.4 [A System Operator shall be entitled under the terms of the Code to make SO Interconnector Trades.]

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A.2.5.5 [A System Operator shall not conduct any SO Interconnector Trades before it calculates the Final Physical Notification Quantity (qFPN lh(t)) of the Interconnector for the relevant balancing market Trading Period.]

A.2.5.6 The Market Operator shall derive the value of the Dispatch Quantity (qDuoh(t)), for each Generator Unit, u, which has Priority Dispatch, and which is non-dispatchable, for each Bid Offer Acceptance, o, in Period, h, as follows:

(a) The value shall be equal to the Final Physical Notification Quantity (qFPNuh(t)) for the Generator Unit, determined in accordance with paragraph A.2.4.3, for each time in Period, h, where the unit does not have a Dispatch Instruction applying to it; and

(b) The Market Operator shall determine the value in accordance with paragraph A.2.5.3 for each time in respect of which a Dispatch Instruction applies to the unit.

A.2.5.7 The Market Operator shall derive the Dispatch Quantity (QDuγ) for each Generator Unit, u, in Imbalance Settlement Period, γ, by integrating the associated function of time Dispatch Quantity (qDuoγ(t)) reflecting the last Dispatch Instruction in effect from time to time during the Imbalance Settlement Period, with respect to time across the Imbalance Settlement Period.

A.2.5.8 Each System Operator shall submit to the Market Operator the Dispatch Quantity (qDloh(t)) in respect of each Interconnector, l, which is linked to its Jurisdiction, for each Bid Offer Acceptance, o, in Period, h.

A.2.5.9 The Dispatch Quantity (qDuoh(t)) for each Interconnector Residual Capacity Unit and each Interconnector Error Unit, u, for each Bid Offer Acceptance, o, in Period, h, shall be equal to the Dispatch Quantity of the relevant Interconnector, l.

A.2.5.10 Each System Operator shall submit to the Market Operator the SO Interconnector Trade Quantity and Price (in the form of Accepted Bid and Offer Quantities, QABuoih, QAOuoih, and Bid Offer Price, PBOuβoih) for each Interconnector Residual Capacity Unit, u, relevant to an Interconnector, l, which is linked to its Jurisdiction, for each Bid Offer Acceptance, o, for Band, i, in Period, h, and shall identify for each such Bid Offer Acceptance the Interconnector, Interconnector Direction, Initiating TSO, TSO counterparty, Trade Type, Reason Code, and Flags.

A.2.5.11 Each System Operator shall submit to the Market Operator the Outturn Availability Quantity (qAVAILOuh(t)) in respect of each Generator Unit u, which is registered within its Jurisdiction.

A.2.6 Metered Quantity DataA.2.6.1 Each Meter Data Provider shall submit to the Market Operator the Metered

Quantities (QMuγ, QMvγ, and QMlγ) for each Generator Unit, u, Supplier Unit, v, and Interconnector, l, as applicable, which is registered within, or linked to, its Jurisdiction in each Imbalance Settlement Period, γ.

A.2.6.2 The Non-Interval Energy Proportion Factor (FNIEPvγ) is a factor for a Supplier Unit, v, in an Imbalance Settlement Period, γ, greater than or equal to zero and less than or equal to one, which represents the proportion of the Metered Quantity that is in respect of non-Interval Metering.

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[A.2.6.3] Each Meter Data Provider shall submit to the Market Operator the Non-Interval Energy Proportion Factor (FNIEPvγ) for each Supplier Unit, v, which is registered within its Jurisdiction, in Imbalance Settlement Period, γ .

A.2.6.3[A.2.6.4] The value of the Metered Quantity (QMuγ) for each Interconnector Error Unit and each Interconnector Residual Capacity Unit, u, shall be equal to the Metered Quantity (QMlγ) of the relevant Interconnector, l.

A.2.6.4[A.2.6.5] The value of the Metered Quantity (QMuγ) for each Generator Unit, u, which is an Assetless Unit or a Trading Unit, shall be deemed to be zero.

Explanatory Note

The following two paragraphs have been added to enact the treatment of Demand Side Units in the balancing and imbalance arrangements. A high level overview of the treatment is as follows:

- It is assumed that the set up for a DSU will be based on at least 2 units on a trading site (the DSU and a Trading Site Supplier Unit). A DSU could participate in the ex-ante markets, and would submit a PN, COD and TOD (in accordance with the Data Submission section) to the balancing market like a Generator Unit with a positive output range.

- Make QM for the DSU = QD (assume they met their required dispatch);

- Make QM for the associated TSSU = -QD.

This would have the following outcomes:

- If a DSU achieves an ex-ante market position, submit a PN, and they are run to that position, there will be no incs/decs, and with QM = QD, they will be deemed in balance, so no BM settlement on the DSU. The associated TSSU would have QM = -QD, and with QEX = 0, they would be deemed in imbalance, and would pay back the DSU’s ex-ante position through the imbalance price.

- If a DSU is inc’d, it is assumed they have delivered and therefore they would receive the imbalance price and potentially a premium. The associated TSSU would pay back this inc volume at the imbalance price only.

- If the DSU is dec’d, it is assumed they have delivered, therefore they would pay back at the imbalance price or get a discount for this amount if applicable. The QM = -QD on the associated TSSU would not reflect the DSU’s dec volume, as the dec means that a reduction in the demand (and the benefit thereof which would have been accounted for on a separate Supplier Unit) did not materialise, therefore there would be no settlement of the dec volume through the TSSU to remove the benefit from the DSU.

The net result of this treatment is that the benefit of materialised demand reductions, which would be accounted for on a separate Supplier Unit at the Imbalance Price, is removed from the Demand Side Unit to ensure against double-counting.

A.2.6.5[A.2.6.6] The value of the Metered Quantity (QMuγ) for each Generator Unit, u, which is a Demand Side Unit, shall be deemed to be equal to the Dispatch Quantity (QDuγ) of that Demand Side Unit.

A.2.6.6[A.2.6.7] The value of the Metered Quantity (QMvγ) for each Trading Site Supplier Unit, v, which is on a Trading Site, s, associated with a Generator Unit, u, which is a Demand Side Unit, shall be deemed to be equal to the negative of the Dispatch Quantity (QDuγ) of that Demand Side Unit.

A.2.7 Timing Conventions[A.2.7.1] A time is deemed to be an instant in time, and to have no duration.

[A.2.7.2] The Trading Period for the balancing market is the period of time relevant to the trading of energy in the balancing market. It is defined in [section from Data Submission]. It is represented by the subscript for a generalised period, h.

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A.2.7.1[A.2.7.3] The Intraday Trade Duration is the period relevant to the trading of energy in the intraday market, which is the period covered by a product in the intraday market. It can vary depending on the products in the market[, as defined in NEMO rules], and are assumed for the calculations in this Chapter to be either one hour or thirty minutes. It is represented by the subscript for a generalised period, h.

A.2.7.2[A.2.7.4] The Day-ahead Trade Duration for a day-ahead market trade is the period relevant to the trading of energy in the day-ahead market, which is the period covered by a traded product in the day-ahead market. It can vary depending on the products in the market[, as defined in NEMO rules], and are assumed for the calculations in this Chapter to be either one hour or thirty minutes. It is represented by the subscript for a generalised period, h.

A.2.7.3[A.2.7.5] The Imbalance Pricing Period is the period within an Imbalance Settlement Period relevant to the calculations for the execution of the Imbalance Pricing Process. It is defined in [section on Imbalance Pricing]. It is represented by the subscript φ.

A.2.7.4[A.2.7.6] The Imbalance Settlement Period is a thirty minute period beginning on each hour or half hour. It is represented by the subscript γ.

A.2.7.5[A.2.7.7] The Aggregated Settlement Period is the period relevant to the calculation of imbalance quantities covering one or multiple Imbalance Settlement Periods for the execution of the Imbalance Settlement Process. It is represented by the subscript α.

A.2.7.6[A.2.7.8] The Intraday Interconnector Trade Duration is the period relevant to the scheduling of energy flows on interconnectors in the intraday market. It is assumed for the calculations in this chapter to be thirty minutes. It is represented by the subscript for a generalised period, h.

A.3 DETERMINATION OF TIMES AND RELEVANT COMMERCIAL OFFER DATA FOR BID OFFER ACCEPTANCES

A.3.1 Times Relevant to Bid Offer Acceptances

Explanatory Note

Changes made to this section reflect changes to how the Instruction Profiling functionality is expected to work. It is intended that instruction profiles would be created for each Dispatch Instruction which are the physical instructions issued by the System Operators, and also Pseudo-Dispatch Instructions, which are settlement constructs in order to have closed acceptances of open instructions. Therefore every BOA would result from a DI, either a physical one, or a pseudo one. Definitions on when a Pseudo-Dispatch Instruction is created, what constitutes its “effective time” and “issue time”, will be outlined in the instruction profiling section.

A.3.1.1 The Market Operator shall determine the Bid Offer Acceptance Time for each Bid Offer Acceptance, o, to be the Instruction Issue Time of the Dispatch Instruction relevant to the Dispatch Quantity (qDuoh(t)) for the Bid Offer Acceptance as defined in [the section on Instruction Profiling].

A.3.1.2 The Market Operator shall determine the Bid Offer Opening Time for each Bid Offer Acceptance, o, to be the Instruction Effective Time of the Dispatch Instruction relevant to the Dispatch Quantity (qDuoh(t)) for the Bid Offer Acceptance as defined in [the section on Instruction Profiling].

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[A.3.2] Commercial Offer Data Format for Settlement Calculations[A.3.2.1] For the purposes of the Settlement process, tThe Market Operator shall, for

each Generator Unit, u, and for each period, h, derive a set of Price Quantity Pairs comprising a single set of Quantities each having two prices applicable (an Incremental Price and a Decremental Price), from the individual sets of Incremental and Decremental Price Quantity Pairs (Puih and quih), submitted by each Participant through its Commercial Offer Data in accordance with [section in Data Submission], as follows:

[(a)] The Quantities (quih) for the single set of Price Quantity pairs Pairs shall be the Quantities in each set of Incremental and Decremental Price Quantity Ppairs submitted by the Participant, ranked in order of increasing Quantity value, and assigned in this order a Band index, i. For positive Quantity values, the Band index, i, shall increase from zero with every Quantity increasing from zero. For negative Quantity values, the Band index, i, shall decrease from zero with every Quantity decreasing from zero. For Quantities equal to zero, the Band, i, shall be zero;

[(b)] The Incremental Price (PINCuih) for the Quantity (quih) in the single set of Price Quantity pPairs shall be the Price from the set of Incremental Price Quantity Pairs applicable at that Quantity. The Decremental Price (PDECuih) for the Quantity (quih) in the single set of Price Quantity Pairs shall be the Price from the set of Decremental Price Quantity pPairs applicable at that Quantity.

A.3.1.3[A.3.2.2] The Market Operator shall derive the Bid Offer Upper Range Quantity (qBOURuih(t)) and Bid Offer Lower Range Quantity (qBOLRuih(t)) for each Generator Unit, u, for each Band, i, in each Period, h, from the sets of Price Quantity Pairs derived under paragraph A.3.2.1, as follows:

[(a)] The Bid Offer Upper Range Quantity (qBOURuih(t)) will be equal to the Quantity (quih) for the relevant Price Quantity pPair derived under paragraph A.3.2.1, for Band, i, where i ≥ 0;

[(b)] The Bid Offer Lower Range Quantity (qBOLRuih(t)) will be equal to the Quantity (quih) for the relevant Price Quantity pPair derived under paragraph A.3.2.1, for Band, i, where i ≤ 0.

[A.3.2.3] The Market Operator shall derive the Bid Offer Price (PBOuih) for each Generator Unit, u, for each Band, i, in each Period, h, from the single set of Price Quantity pPairs derived under paragraph A.3.2.1, using the relevant set of Commercial Offer Data as determined in Section A.3.3, as follows:

[(a)] If the quantity to which the Bid Offer Price applies has a positive value, the Bid Offer Price shall be the Incremental Price (PINCuih ) of the relevant Price Quantity pPair;

[(b)] If the quantity to which the Bid Offer Price applies has a negative value, the Bid Offer Price shall be the Decremental Price (PDECuih ) of the relevant Price Quantity pPair.

A.3.1.4[A.3.2.4] The value of the Bid Offer Price (PBOuih) for a Generator Unit, u, which has Priority Dispatch, which is non-dispatchable, and which has zero variable costs, for Band, i, in Period, h, shall be deemed to be zero if the quantity to which the Bid Offer Price applies is negative, with the exception of when the quantity considered is a Bid Price Only Accepted Bid Quantity in accordance with section A.7.

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A.3.2[A.3.3] Commercial Offer Data to be Used

Explanatory Note

Commercial Bid Offer Data submitted in accordance with the paper on Balancing Market Data Submission must be provided in Complex Bid Offer Data Format and may also be provided in Simple Bid Offer Data Format.

Extra text has been added here to give effect to the market power decision. An additional test for the Market Power Condition is added to determine which COD set should be used in the calculation of balancing market quantities, and the determination of the prices of those quantities, for Settlement processes. If the Market Power Condition is true, then the Complex COD, which outside of the TSC rules would have a Bidding Code of Practice apply to it, would be used.

The Market Power condition is to determine whether the unit is “non-energy” using the results of the Imbalance Pricing Flagging and Tagging process. There are two aspects of the Flagging and Tagging process which determine whether or not a unit is non-energy:

- The System Operator flag, which determines if a unit is at a certain output level due to a system constraint and is therefore non-energy; and

- The NIV Tag, which determines that a unit is non-energy in the absence of sufficient System Operator flagged actions being tagged out to meet the NIV (i.e. if there are more unflagged actions than the NIV, additional actions are tagged out and in this way are deemed to be non-energy).

If a unit is found to be either flagged or tagged (fully or partially), it is deemed to be non-energy in that period for the purposes of the Market Power decision. A unit is SO flagged if the flag is set to zero. The unit is NIV tagged if the tag variable is set to anything other than a value of one. Therefore the product of these would have to be equal to one for the unit to not be flagged or tagged, meaning that the Market Power conditions apply if the value of the product is less than one.

Using both the Flag and Tag elements also ensures the market power conditions are robust so that if changes to the SO Flagging approach were to be taken and more emphasis given to NIV tagging approaches, then the Market Power conditions would still apply to those units deemed to be non-energy under the NIV tagging approach.

A.3.2.1[A.3.3.1] For the purposes of calculating the Imbalance Price in an Imbalance Pricing Period, φ, in calculating Accepted Bid Quantity and Accepted Offer Quantity, and determining the relevant Bid Offer Price, in respect of a Bid Offer Acceptance, the Market Operator shall use the following Commercial Offer Data:

(a) If the Bid Offer Acceptance Time is before the Gate Closure for the Imbalance Settlement Period containing the Bid Offer Opening Time, the most recently submitted valid Complex Bid Offer Format Data for the relevant Trading Day as at the Bid Offer Acceptance Time;

(b) Otherwise, the most recently submitted valid Simple Bid Offer Format Data for the relevant Imbalance Settlement Period as at the Bid Offer Acceptance Time.

A.3.2.2[A.3.3.2] For the purposes of calculating settlement quantities in an Imbalance Settlement Period, γ, in calculating Accepted Bid Quantity and Accepted Offer Quantity, and determining the relevant Bid Offer Price, in respect of a Bid Offer Acceptance, the Market Operator shall use the following Commercial Offer Data:

(a) If the Bid Offer Acceptance Time is before the Gate Closure for the Imbalance Settlement Period containing the Bid Offer Opening Time, the most recently submitted valid Complex Bid Offer Format Data for the relevant Trading Day as at the Bid Offer Acceptance Time;

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(b) If any Bid Offer Acceptance for Generator Unit, u, at rank, k, has, after applying the Flagging and Tagging process in accordance with [section on Imbalance Pricing], a Net Imbalance Volume Tag (TNIVukφ) with a value less than one, or a System Operator Flag (FSOukφ) with a value less than one, for any Imbalance Pricing Period, φ, within the Imbalance Settlement Period, γ, the most recently submitted valid Complex Bid Offer Format Data for the relevant Trading Day as at the Bid Offer Acceptance Time.

where:

(i) FSOukφ is the System Operator Flag for Generator Unit, u, and rank, k, in Imbalance Pricing Period, φ, determined in accordance with [section on Imbalance Pricing] and where in the absence of a value for the period resulting from the process outlined in [Section on Imbalance Pricing] a value of one will be used; and

(ii) TNIVukφ is the value of the Net Imbalance Volume Tag for Generator Unit, u, and rank, k, in Imbalance Pricing Period, φ, determined in accordance with [section on Imbalance Pricing] and where in the absence of a value for the period resulting from the process outlined in [Section on Imbalance Pricing] a value of one will be used.

(c) Otherwise, the most recently submitted valid Simple Bid Offer Format Data for the Imbalance Settlement Period as at the Bid Offer Acceptance Time.

A.3.2.3[A.3.3.3] Where in accordance with paragraphs A.3.3.1 or A.3.3.2 the Market Operator is required to use Complex Bid Offer Format Data, it shall use the following Commercial Offer Data for each Imbalance Settlement Period relevant to the Bid Offer Acceptance:

(a) The Trading Day Specific Complex Bid Offer Format Data (if any) that was valid for the Imbalance Settlement Period containing the Bid Offer Opening Time most recently submitted as at the Bid Offer Acceptance Time; or

(b) Otherwise, the valid Default Complex Bid Offer Format Data that had been most recently submitted as at the Bid Offer Acceptance Time.

A.3.2.4[A.3.3.4] Where in accordance with paragraphs A.3.3.1 or A.3.3.2 the Market Operator is required to use Simple Bid Offer Format data, it shall use the following Commercial Offer Data for each Imbalance Settlement Period relevant to the Bid Offer Acceptance:

(a) The Trading Period Specific Simple Bid Offer Format Data (if any) that was valid for the Imbalance Settlement Period relevant to the Bid Offer Acceptance and had been most recently submitted as at the Bid Offer Acceptance Time; or

[(b)] Otherwise, the Price Quantity Ppair data of the Complex Bid Offer Format Data that it would be required to use in accordance with paragraph A.3.3.3(a) or A.3.3.3(b), as applicable, were that paragraph to apply.

A.4 TRADING BOUNDARY AND TREATMENT OF LOSSES

Explanatory Note

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Functionality for applying the loss adjustment factors to the variables.

A.4.1 Trading Boundary

Explanatory Note

The provisions on the Trading Boundary are similar to that in the SEM TSC in that activity is deemed to take place at the boundary, necessitating the application of loss factors. Text from the TSC has been removed to reflect the differences between the SEM and the Balancing Market:

- The SEM is a Pool, and reflects a single volume of all generation being sold, and all consumption being bought;

- In the Balancing Market the volumes reflect differences between ex-ante market volumes bought and sold, the balancing market volumes bought and sold, and actual outturn generation, consumption or imbalance of different units. It no longer suffices to think in terms of all units delivering energy being bought by all units taking energy. For example, a negative imbalance may not be “taking energy” but rather a reduction in the amount of energy being delivered.

A definition of Trading Boundary would be provided as part of the Glossary, and would be similar to that in the SEM. An example is provided in the first paragraph below.

A.4.1.1 The Trading Boundary is a notional boundary between all points on the Transmission System and all points on the Distribution System. The Trading Boundary is the notional balancing point for generation and supply and is the point of sale for trading in the SEM at which the title for all products and services settled through the trading arrangements set out in the Code transfers. All volumes traded or settled at the Trading Boundary are adjusted, where required, to reflect Transmission Losses and (where applicable) Distribution Losses. For the avoidance of doubt, for all Supplier Units or Generator Units that are Distribution Connected, the Trading Boundary is not the specific boundary between the Transmission System and Distribution System for that Unit and so appropriate Combined Loss Adjustment Factors also apply to volumes associated with these Units in order to ensure that they are appropriately adjusted for Transmission Losses and Distribution Losses incurred as electricity is transported to (or from) the Trading Boundary from (or to) the relevant boundary of the Transmission System and the Distribution System for that Unit and then from (or to) the point of connection of that Unit.

A.4.1.2 Before submitting to the Market Operator Meter Data relating to a Generator Unit (other than a Demand Side Unit), or a Supplier Unit, that is Distribution Connected and for which the Distribution System Operator provides the Metered Quantity data, each Distribution System Operator shall apply the appropriate Distribution Loss Adjustment Factor to the Meter Data values.

A.4.2 Setting of Loss Adjustment FactorsA.4.2.1 At least [four months] before the start of each Tariff Year, each System

Operator shall submit to the Regulatory Authorities a set of Transmission Loss Adjustment Factors for each Generator Unit, other than a Demand Side Units, that is Connected within its Jurisdiction and for each Interconnector linked to that Jurisdiction, calculated in co-operation with the System Operator in the other Jurisdiction and in accordance with the statutory and Licence requirements pertaining within its Jurisdiction, for each Imbalance

13

Settlement Period in the Tariff Year. The Transmission Loss Adjustment Factors for each Interconnector shall be applicable to each Interconnector Error Unit and Interconnector Residual Capacity Unit registered to the relevant Interconnector.

A.4.2.2 In determining Transmission Loss Adjustment Factors the System Operator shall incorporate Transmission Losses incurred on the relevant Interconnector as estimated in consultation with the Interconnector Owner.

A.4.2.3 The System Operator shall incorporate the estimated Transmission Losses incurred on the Interconnector into the Transmission Loss Adjustment Factors having regard to its expectation of the pre-dominant direction of flow on the Interconnector in the relevant Trading Period.

A.4.2.4 At least [three months] before the start of each Tariff Year, each Distribution System Operator shall provide the relevant System Operator with a set of Distribution Loss Adjustment Factors for each Generator Unit (other than Demand Side Units) that is Distribution Connected within its Jurisdiction, calculated in accordance with the statutory and Licence requirements pertaining within its Jurisdiction, for each Imbalance Settlement Period in the Tariff Year, and including the relevant supporting information to enable the System Operator to calculate the corresponding Combined Loss Adjustment Factors.

A.4.2.5 At least [two months] before the start of each Tariff Year, or within [five Working Days] of its receipt from the Regulatory Authorities, whichever is later, each System Operator shall provide to the Market Operator [in accordance with Appendix K “Market Data Transactions” ]the System Parameters Data Transaction which shall comprise a complete set of Combined Loss Adjustment Factors for each Generator Unit (other than Demand Side Units, Interconnector Error Units or Interconnector Residual Capacity Units) Connected within its Jurisdiction, and each Interconnector linked to that Jurisdiction, for each Imbalance Settlement Period in that Tariff Year.

A.4.2.6 At least [two months] before the start of each Tariff Year, or within [five Working Days] of its receipt from the Regulatory Authorities, whichever is later, each System Operator shall provide the Market Operator with a complete set of Transmission Loss Adjustment Factors for each Generator Unit (other than Demand Side Units) that is Connected within its Jurisdiction for each Imbalance Settlement Period in that Tariff Year in accordance with those prepared and submitted to the Regulatory Authorities under paragraph A.4.2.1.

A.4.2.7 At least [two months] before the start of each Tariff Year each System Operator shall provide the Market Operator with a complete set of Distribution Loss Adjustment Factors for each Generator Unit (other than Demand Side Units) that is Distribution Connected within its Jurisdiction for each Imbalance Settlement Period in that Tariff Year.

A.4.2.8 The Market Operator shall publish the approved Combined Loss Adjustment Factor value(s) within [5 Working Days] of receipt of the System Parameters Data Transaction.

A.4.2.9 The Market Operator shall publish the approved Distribution Loss Adjustment Factor value(s) and Transmission Loss Adjustment Factor value(s) within [5 Working Days] of receipt of the Loss Adjustment Factors Data Transaction.

A.4.2.10 The Transmission Loss Adjustment Factor (FTLAFvγ) shall be equal to 1 for each Supplier Unit, v.

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A.4.2.11 The Combined Loss Adjustment Factor (FCLAFuγ) for each Generator Unit, u, in Imbalance Settlement Period, γ, shall be calculated by the relevant System Operator as follows:

FCLAFuγ=Round (FTLAF uγ×FDLAFuγ )

where:

(a) Round(x) is a function that rounds x to 3 decimal places;

(b) FTLAFuγ is the Transmission Loss Adjustment Factor for Generator Unit, u, in Imbalance Settlement Period, γ; and

(c) FDLAFuγ is the Distribution Loss Adjustment Factor for Generator Unit, u, in Imbalance Settlement Period, γ. In cases where a Distribution Loss Adjustment Factor has been applied to a variable in advance of data submission in accordance with paragraph A.4.1.2, a value of one for the Distribution Loss Adjustment Factor shall be used for the calculation of the Combined Loss Adjustment Factor to be applied to that variable.

A.4.2.12 The Combined Loss Adjustment Factor (FCLAFvγ) for each Supplier Unit, v, in Imbalance Settlement Period, γ, shall be set equal to 1.

A.4.2.13 The Combined Loss Adjustment Factor (FCLAFuγ) for each Demand Side Unit, u, in Imbalance Settlement Period, γ, shall be set equal to 1.

A.4.3 Application of Loss Adjustment Factors

Explanatory Note

Intention of equations in this section are:

- For internal participants, apply combined loss adjustment factor to any variable desired, signified throughout the document by the use of the term “Loss-Adjusted” and an “LF” in the variable name;

- For cross border variables, apply the factor like above if a positive value (i.e. exporting), but apply the reciprocal (1 / factor) if a negative value (i.e. importing).

- In these rules, terms finishing LF have the loss factor applied in that calculation as if the original term were multiplied by the applicable loss factor in that calculation. Other terms may be defined from data that has already been loss factor adjusted so do not have LF at the end of the term as no further loss factor adjustment is required. These differences arise as a result of calculations which involve both ex-ante market transactions (which are loss factor adjusted at submission and require no further adjustment) and balancing market transactions (which must be explicitly loss factor adjusted in settlement).

A.4.3.1 In this Code, the term ‘Loss-Adjusted’ applied to any variable, or the inclusion of the letters ‘LF’ at the end of any variable term, denotes that a value is to be calculated at the Trading Boundary, through application of the relevant Combined Loss Adjustment Factor as determined under paragraph A.4.2.11.

A.4.3.2 Where the Market Operator is required to calculate or determine a Loss-Adjusted variable which relates to a Generator Unit, u, other than an Interconnector Error Unit or an Interconnector Residual Capacity Unit, and each Supplier Unit, v, in respect of an Imbalance Settlement Period, γ, and where XXXγ is the variable before the application of Transmission Losses and Distribution Losses, it shall apply the following calculation:

15

XXXLF γ=XXXγ ×FCLAF γ

where:

(a) XXXLFγ is the relevant Loss-Adjusted variable to be determined; and

(b) FCLAFγ is the Combined Loss Adjustment Factor for Generator Unit, u, or Supplier Unit, v, in Imbalance Settlement Period, γ, determined under paragraph A.4.2.11.

A.4.3.3 Where the Market Operator is required to calculate a Loss-Adjusted variable which relates to an Interconnector Error Unit or Interconnector Residual Capacity Unit, in respect of an Imbalance Settlement Period, γ, and where XXXuγ is the variable before application of Transmission Losses and Distribution Losses, it shall apply the following calculation:

If XXX ≥0 thenXXXLFuγ=XXX uγ×FCLAFlγelse

XXXLFuγ=XXX uγFCLAF lγ

where:

(a) XXXLFuγ is the relevant Loss-Adjusted variable to be determined; and

(b) FCLAFlγ is the Combined Loss Adjustment Factor for the relevant Interconnector, l, in Imbalance Settlement Period, γ, determined under paragraph A.4.2.11.

A.5 IMBALANCE COMPONENT PAYMENTS AND CHARGES

Explanatory notes

- Imbalance Component: Applies the imbalance settlement price to any difference between the ex-ante volumes procured and the metered volumes delivered. Includes instructed imbalances from dispatch instructions (implements part of decision to remunerate these at the better of the imbalance settlement price or the bid/offer price, rest of implementation through premium/discount component), and uninstructed imbalances from PN submission, underdelivery or overdelivery.

- The balancing market will commence with a half hourly trading/imbalance settlement period. The ex-ante markets offer hourly period products. Therefore since imbalance quantities are the difference between metered quantities and ex-ante contracted quantities, and ex-ante contract quantities will apply to periods longer than the imbalance settlement period, the determination of imbalances for each imbalance settlement period requires some form of allocation of ex-ante contract quantities to those shorter periods.

A.5.1 Setting of Imbalance Payment ParametersA.5.1.1 If requested by the Regulatory Authorities, the [Market Operator] shall report

to the Regulatory Authorities proposing the following parameters to be used in the calculation of Imbalance Payments and Charges for that Year:

(a) The value, or description of the methodology for determining the value, of the Imbalance Weighting Factor (WFIMBγ) in each Imbalance Settlement Period, γ, for Year, y.

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A.5.1.2 The [Market Operator's] report must set out any relevant research or analysis carried out by the Market Operator and the justification for the specific values, or sources for values, or methodology proposed. The report may, and shall if so requested by the Regulatory Authorities, include alternative values or methodologies from those proposed and must set out the arguments for and against such alternatives.

A.5.1.3 The Market Operator shall publish the approved value for, or methodology for determining, the parameter referred to in paragraph A.5.1.1, and the date and time on which it comes into effect, within [5 Working Days] of receipt of the Regulatory Authorities' determination.

A.5.1.4 The duration of the Aggregated Settlement Period, α, shall be the period determined by the Regulatory Authorities from time to time. The Market Operator shall publish the approved duration of the Aggregated Settlement Period within [5 Working Days] of receipt of the Regulatory Authorities’ determination.

A.5.1.5 If the Regulatory Authorities determine a revised duration for the Aggregated Settlement Period, α, under paragraph A.5.1.4, the revised duration takes effect at a time specified by the Regulatory Authorities in their determination (which must not be earlier than [six Months] from the date of the determination).

A.5.2 Calculation of Ex-Ante Quantities

Explanatory Note

Intention of the equation below is as follows:

- Calculate the imbalance over the Aggregated Settlement Period if it was greater than the Imbalance Settlement Period (AGSP envisaged to be the same as the ISP at first, but could be moved to 1 hour if required in future) between products with trading periods of greater than ISP length, and the metered quantities, and weight this imbalance into each Imbalance Settlement Period (half hour);

- When this imbalance in each ISP is taken away from the metered quantity in that ISP, it results in the split of the ex-ante quantity for the products considered into each ISP.

- If the imbalance is calculated over the Imbalance Settlement Period rather than the Aggregated Settlement Period, then any products with length greater than ISP will be split into equal proportions into each ISP.

- The ex-ante products with trading periods of half an hour are then directly added onto the split-up ex-ante quantity, giving the total ex-ante quantity in that ISP.

- Also need to build into equation the removal of averaging if no ASP-granular products are traded in a period. E.g. if there is no day-ahead or hour trading period intraday products traded, and the unit has only traded half-hour granular products, and the imbalance settlement period is half an hour, QEX should only be equal to the sum of the half-hour granular products, rather than also considering a split of the imbalances against non-existant hourly products. Instead of the FIMBAVG component which was previously introduced, this is now done with logical statements where different calculations are done depending on if the hourly products have been traded by a unit or not.

- Previous iterations of this document were written with the assumption that the quantities submitted for ex-ante contracts were in MWh units. Changes have been made to reflect clarification that MW unit quantities will be sent through.

A.5.2.1 When the Aggregated Settlement Period Duration is shorter than or equal to the Imbalance Settlement Period Duration, the provisions in paragraphs A.5.2.2 to A.5.2.5 shall apply.

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[A.5.2.2] For each Day-ahead Trade Quantity (QTDAxh) and Intraday Trade Quantity (QTIDxh) which has a Trade Duration longer than the Imbalance Settlement Period Duration, the Market Operator shall calculate the quantity of each Trade, x, for each Supplier Unit, v, and each Generator Unit, u, other than an Interconnector Error Unit or Interconnector Residual Capacity Unit, to be allocated into each Imbalance Settlement Period, γ, as follows:

❑❑❑❑❑❑❑

❑❑❑❑❑❑❑

where:

[(a)] QTDAxh is the Day-ahead Trade Quantity for Trade, x, for Generator Unit, u, or Supplier Unit, v, in Day-ahead Trading Period, h;

[(b)] QTIDxh is the Intraday Trade Quantity for Trade, x, for Generator Unit, u, or Supplier Unit, v, in Intraday Trading Period, h;

[(c)] DISP is the Imbalance Settlement Period Duration;

[(d)] DTDAx is the Day-ahead Trade Duration of Trade, x; and

[(e)] DTIDx is the Intraday Trade Duration of Trade, x.

[A.5.2.3] The Market Operator shall calculate the Ex-Ante Quantity (QEXγ) for each Supplier Unit, v, and each Generator Unit, u, other than an Interconnector Error Unit or Interconnector Residual Capacity Unit, in each Imbalance Settlement Period, γ, as follows:

QEX γ=∑x

(❑❑ (❑❑) )❑❑∑❑

❑❑+∑x

(❑❑ (❑❑) )❑❑∑❑

❑❑

where:

[(a)] QTDAxh qTDAxh is the Day-ahead Trade Quantity for Trade, x, for Generator Unit, u, or Supplier Unit, v, in Day-ahead Trading Period, h;

[(b)] QTIDxh qTIDxh is the Intraday Trade Quantity for Trade, x, for Generator Unit, u, or Supplier Unit, v, in Intraday Trading Period, h;

(a)[(c)] DISP is the Imbalance Settlement Period Duration;

(b) DTDAx is the Day-ahead Trade Duration of Trade, x;

(c) DTIDx is the Intraday Trade Duration of Trade, x; and

(d) ∑❑

❑means the sum of the quantity for each Trade, x, whose Trade Duration was greater than the Imbalance Settlement Period Duration, calculated in accordance with paragraph A.5.2.2; and

[(d)] ∑x

means the sum of the quantities for each Trade, x, from the day-

ahead market or the intraday market, as the case may be within whose Day-ahead Trade Period or Intraday Trade Period, h, as the case may be, the Imbalance Settlement Period, γ, falls in whole or in partmeans the sum of the quantities for each Trades, x, whose Trade

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Duration was less than or equal to the Imbalance Settlement Period Duration.

[A.5.2.4] The Market Operator shall calculate the quantity of the final Intraday Interconnector Schedule Quantity (QICSIDlh) for each Interconnector, l, to be allocated into each Imbalance Settlement Period, γ, as follows :

[(a)] If the final Intraday Interconnector Schedule Quantity (QICSIDlhqICSIDlh) has an Intraday Interconnector Trade Duration longer than the Imbalance Settlement Period Duration, then:

QICSID lγ=ICSID lh×❑❑

(e)[(b)] Otherwise:

QICSIDlγ=∑h≤γICSID lh (( ))

where:

[(i)] QICSIDlh qICSIDlh is the Intraday Interconnector Schedule Quantity for Interconnector, l, in Intraday Trading Period, h;

(i)[(ii)] ∑h≤γ

means the sum for of the quantities whose Intraday

Interconnector Trade Duration was less than or equal to the Imbalance Settlement Period Duration;

(ii)[(iii)] DISP is the Imbalance Settlement Period Duration; and

(iii)[(iv)] DTICID(Min) is the shortest Intraday Interconnector Trade Duration offered in the intraday market.

A.5.2.2[A.5.2.5] The Market Operator shall calculate the Ex-Ante Quantity (QEXuγ) for each Generator Unit, u, that is an Interconnector Error Unit or Interconnector Residual Capacity Unit, in each Imbalance Settlement Period, γ, as follows:

QEXuγ=QICSID lγ

where:

(a) QICSIDlγ is the Intraday Interconnector Schedule Quantity for Interconnector, l, relevant to the Interconnector Error Unit or Interconnector Residual Capacity Unit, u, in Imbalance Settlement Period, γ.

A.5.2.3[A.5.2.6] When the Aggregated Settlement Period Duration is greater than the Imbalance Settlement Period Duration, the provisions in paragraphs A.5.2.7 to A.5.2.10 shall apply.

A.5.2.4[A.5.2.7] For Supplier Units, v, or Generator Units, u, other than an Interconnector Error Unit or Interconnector Residual Capacity Unit, that do not have any Day-ahead Trade Quantities or Intraday Trade Quantities with a Trade Duration longer than the Imbalance Settlement Period Duration, the Market Operator shall calculate the Ex-Ante Quantity for each of those Generator Units, u, and each of those Supplier Units, v, in each Imbalance Settlement Period, γ, as follows:

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QEX γ= ∑x whereh≤ γ

(TDAxh (❑❑) )+ ∑x where h≤ γ

(❑❑ (❑❑) )❑❑

[(a)] q QTDAxh is the Day-ahead Trade Quantity for Trade, x, for Generator Unit, u, or Supplier Unit, v, in Day-ahead Trading Period, h;

[(b)] q QTIDxh is the Intraday Trade Quantity for Trade, x, for Generator Unit, u, or Supplier Unit, v, in Intraday Trading Period, h; and

(a) DISP is the Imbalance Settlement Period Duration;

(b) DTDAx is the Day-ahead Trade Duration of Trade, x;

(c) DTIDx is the Intraday Trade Duration of Trade, x; and

(d)[(c)] ∑xwhere h≤γ

means the sum of the quantities for each Trade, x, whose

Trade Duration was less than or equal to the Imbalance Settlement Period Duration.

A.5.2.5[A.5.2.8] For Supplier Units, v, or Generator Units, u, other than an Interconnector Error Unit or Interconnector Residual Capacity Unit, that have any Day-ahead Trade Quantities or Intraday Trade Quantities with a Trade Duration longer than the Imbalance Settlement Period:

[(a)] For each Day-ahead Trade Quantity (QTDAxhqTDAxh) and Intraday Trade Quantity (QTIDxhqTIDxh) which has a Trade Duration longer than the Aggregated Settlement Period Duration, the Market Operator shall calculate the quantity of each Trade, x, for each Supplier Unit, v, and each Generator Unit, u, to be allocated into each Aggregated Settlement Period, α, as follows:

QTDA xα=TDA xh×❑❑❑

QTIDxα=TIDxh×❑❑❑

(a)[(b)] The Market Operator shall calculate the Ex-Ante Quantity (QEXγ) for each Supplier Unit, v, and each Generator Unit, u, in each Imbalance Settlement Period, γ, as follows:

QEX γ=(QMLF γ− WFIMB γ∑all γ ∈α

WFIMBγ (( ∑all γ∈α

QMLFγ )−( ∑x where h=α

QTDA xh+ ∑x whereh=α

QTID xh)))+ ∑x whereh≤ γ

(❑❑ (❑❑ ) )❑❑+ ∑x whereh≤γ

(❑❑ (❑❑ ))❑❑

where:

(i) DAGSP is the Aggregated Settlement Period Duration;

(ii) DTDAx is the Day-ahead Trade Duration of Trade, x; and

(iii) DTIDx is the Intraday Trade Duration of Trade, x.

(iv) QTIDxh or qTIDxh is the Intraday Trade Quantity for Trade, x, for Supplier Unit, v, or Generator Unit, u, in the Intraday Trade Period, h, relevant to Trade x;

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(v) QTDAxh or qTDAxh is the Day-ahead Trade Quantity for Trade, x, for Supplier Unit, v, or Generator Unit, u, in the Day-ahead Trade Period, h relevant to Trade x;

(vi) WFIMBγ is the Imbalance Weighting Factor for Imbalance Settlement Period, γ;

(vii) QMLFγ is the Loss-Adjusted Metered Quantity for Supplier Unit, v, or Generator Unit, u, in Imbalance Settlement Period, γ;

(viii) ∑xwhere h=α

means the sum of the quantities for each Trade, x,

from the day-ahead market or the intraday market, as the case may be within whose Day-ahead Trade Period or Intraday Trade Period, h, as the case may be, the Aggregated Settlement Period, α, falls in whole or in part; and whose Day-ahead Trade Duration or Intraday Trade Duration, as the case may be, is no shorter than the Aggregated Settlement Period Duration; and

(ix) ∑xwhere h≤γ

means the sum of the quantities for each Trades, x,

whose Trade Duration was less than or equal to the Imbalance Settlement Period Duration to the extent that the same Trade has not already been included in the summation set out in paragraph A.5.2.8(b)(viii).

A.5.2.6[A.5.2.9] For Interconnectors, l, that do not have a final Intraday Interconnector Schedule Quantity with a Trade Duration longer than the Imbalance Settlement Period Duration, the Market Operator shall calculate the Ex-Ante Quantity for each Generator Unit, u, which is an Interconnector Error Unit and an Interconnector Residual Capacity Unit, relevant to Interconnector, l, in each Imbalance Settlement Period, γ, as follows:

QEXuγ=∑h≤ γICSIDlh (())

where:

[(a)] QICSIDlh qICSIDlh is the Intraday Interconnector Schedule Quantity for Interconnector, l, relevant to the Interconnector Error Unit or Interconnector Residual Capacity Unit, u, in Intraday Trade Period, γ;

(a) DISP is the Imbalance Settlement Period Duration;

(b) DTICID(Min) is the shortest Intraday Interconnector Trade Duration offered in the intraday market; and

(c)[(b)] ∑h≤γ


Interconnector Trade Duration was less than or equal to the Imbalance Settlement Period.

A.5.2.7[A.5.2.10] For Interconnectors, l, that have a final Intraday Interconnector Schedule Quantity with an Intraday Interconnector Trade Duration longer than the Imbalance Settlement Period Duration:

(a) The Market Operator shall calculate the quantity of the final Intraday Interconnector Schedule Quantity (QICSIDlh) for each Interconnector,

21

l, to be allocated into each Aggregated Settlement Period, α, as follows:

QICSID lα=ICSID lh×❑❑

(b) The Market Operator shall calculate the Ex-Ante Quantity (QEXuγ) for each Generator Unit, u, which is an Interconnector Error Unit and an Interconnector Residual Capacity Unit, relevant to Interconnector, l, in each Imbalance Settlement Period, γ, as follows:

QEXuγ=(QMLFlγ− WFIMBγ∑all γ∈ α

WFIMB γ (( ∑all γ∈ α

QMLF lγ)−( ∑where h=α

QICSIDlh)))+ ∑where h≤γ

(❑❑ (()) )❑❑

where:

(i) QICSIDlh or qICSIDlh is the Intraday Interconnector Schedule Quantity for Interconnector, l, in Intraday Trading Period, h;

(ii) DAGSP is the Aggregated Settlement Period Duration;

(iii) DTICID(Min) is the shortest Intraday Interconnector Trade Duration offered in the intraday market.

[(iv)] QICSIDlh is the Intraday Interconnector Schedule Quantity for Interconnector, l, in Intraday Trading Period, h;

[(v)] WFIMBγ is the Imbalance Weighting Factor for Imbalance Settlement Period, γ;

(iv)[(vi)] QMLFlγ is the Loss-Adjusted Metered Quantity for Interconnector, l, in Imbalance Settlement Period, γ;

(v)[(vii)] ∑where h=α

means the sum of the quantities within whose

Intraday Trade Period, h, the Aggregated Settlement Period, α, falls in whole or in part; and whose Intraday Interconnector Trade Duration, is no shorter than the Aggregated Settlement Period Duration; and

(vi)[(viii)] ∑where hγ


Interconnector Trade Duration was less than or equal to the Imbalance Settlement Period Duration to the extent that the same Trade has not already been included in the summation set out in paragraph A.5.2.10(b)(vii).

A.5.2.8[A.5.2.11] The Market Operator shall calculate the Ex-Ante Quantity (QEXuγ) for each Assetless Unit, u’, which represents a Nominated Electricity Market Operator, in each Imbalance Settlement Period, γ, as follows:

❑❑(∑❑ (∑❑

(❑❑ (❑❑) )∑❑

(❑❑ (❑❑) ))∑❑

(∑❑

❑❑ (( ))))where:

22

(a) qTDAxh is the Day-ahead Trade Quantity for Trade, x, for Generator Unit, u, or Supplier Unit, v, in Day-ahead Trading Period, h;

(b) qTIDxh is the Intraday Trade Quantity for Trade, x, for Generator Unit, u, or Supplier Unit, v, in Intraday Trading Period, h;

(c) DISP is the Imbalance Settlement Period Duration;

(d) DTDAx is the Day-ahead Trade Duration of Trade, x;

(e) DTIDx is the Intraday Trade Duration of Trade, x;

(f) ∑❑

❑ means the sum of the quantities for each Trade, x, from the day-ahead market or the intraday market, as the case may be within whose Day-ahead Trade Period or Intraday Trade Period, h, as the case may be, the Imbalance Settlement Period, γ, falls in whole or in part, submitted by the Scheduling Agent represented by the Assetless Unit, u’, for that unit in accordance with section A.2.3;

(g) qICSIDlh is the Intraday Interconnector Schedule Quantity for Interconnector, l, in Intraday Trade Period, γ;

(h) DTICID(Min) is the shortest Intraday Interconnector Trade Duration offered in the intraday market;

(i) ∑❑

❑ means the sum for all Generator Units, u, and Supplier Units, v, for whom the Assetless Unit, u’, represents a Scheduling Agent which submits Contracted Quantities for that unit in accordance with section A.2.3;

(j) ∑❑

❑ means the sum for all Interconnectors, l, for whom the Assetless Unit, u’, represents a Scheduling Agent which submits final Intraday Interconnector Schedule Quantities for that Interconnector in accordance with section A.2.3; and

(k) ∑❑

❑ means the sum for of the quantities whose Intraday Interconnector Trade Duration was less than or equal to the Imbalance Settlement Period.

A.5.2.9 The Ex-Ante Quantities (QEXγ) calculated in Section section A.5.2 shall, for the purposes of further uses in this Chapter, be read as QEXuγ where it relates to a quantity for a Generator Unit, and be read as QEXvγ where it relates to a quantity for a Supplier Unit.

[A.5.3] Calculation of Imbalance Component Payments or and Charges

Explanatory Note


- Apply the imbalance settlement price to all imbalances in the imbalance settlement period.

- This is done by applying it to the difference between what the unit actually did (metered) and what it wanted to do according to the ex-ante markets (QEX). This imbalance volume includes the (delivered amounts of) uninstructed imbalance (difference between metered level and dispatched level), instructed imbalance (difference between dispatched level and PN’d level) and notified imbalance (difference between PN’d level and ex-ante market level).

- If specific prices other than the imbalance settlement price are applicable to different subsets of this total volume, it is taken care of in other calculations later in

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this section.

A.5.2.10[A.5.3.1] Except as provided in paragraph A.5.3.3, the Market Operator shall calculate the Imbalance Component Payment or Charge (CIMBuγ) for each Generator Unit (other than an Interconnector Error Unit or an Interconnector Residual Capacity Unit), u, in each Imbalance Settlement Period, γ, as follows:

CIMBuγ=PIMBγ× (QMLF uγ−QEX uγ )

where:

(a) PIMBγ is the Imbalance Settlement Price in Imbalance Settlement Period, γ[, as calculated in section on Imbalance Pricing];

(b) QMLFuγ is the Loss-Adjusted Metered Quantity for Generator Unit, u, in Imbalance Settlement Period, γ; and

(c) QEXuγ is the Ex-Ante Quantity for Generator Unit, u, in Imbalance Settlement Period, γ.

A.5.2.11[A.5.3.2] The Market Operator shall calculate the Imbalance Component Payment or Charge (CIMBvγ) for each Supplier Unit, v, in Imbalance Settlement Period, γ, as follows:

CIMBvγ=PIMBγ× (QMLF vγ−QEX vγ )

where:


(b) QMLFvγ is the Loss-Adjusted Metered Quantity for Supplier Unit, v, in Imbalance Settlement Period, γ; and

(c) QEXvγ is the Ex-Ante Quantity for Supplier Unit, v, in Imbalance Settlement Period, γ.

Explanatory Note


- Apply the imbalance settlement price only to instructed imbalances in the imbalance settlement period in the case where a pumped storage unit is in pumping mode;

- This is done to carry forward a provision from the SEM where it was decided that uninstructed imbalances are not applicable to a pumped storage unit when in pumping mode.

- The QAO and QAB are the calculated instructed imbalances (difference between dispatch level and PN’d level). The undelivered quantities corresponding to these instructed imbalances are taken away so only the delivered portion is remunerated. The biased quantities corresponding to these instructed imbalances are also taken away so only the portion of this volume which is traded in the balancing market, rather than already being traded through an ex-ante market, is remunerated. The max of them is taken to ensure against double counting, because these volumes could be overlapping, i.e. the same volume is both biased and undelivered;

- There are other units who should not be remunerated for uninstructed or instructed imbalances – one which continues on from the SEM TSC Section 5 is autonomous generators (paragraphs 5.19 and 5.20 of SEM TSC). They are only remunerated at the Imbalance Price through CIMB for differences against the ex-ante market

24

position, but are not otherwise considered in charges.

A.5.2.12[A.5.3.3] The Market Operator shall calculate the Imbalance Component Payment or Charge (CIMBuγ) for each Pumped Storage Unit, u, in each Imbalance Settlement Period, γ, for which it is in Pumping Mode (as determined in paragraph A.2.1.3), as follows:

CIMBuγ=PIMBγ×(∑o ∑i

(QAOLF uoiγ−Max (QAOBIAS uoiγ ,QAOUNDELuoiγ ))+∑o∑i

(QABLFuoiγ−Min (QABBIASuoiγ ,QABUNDELuoiγ )))where:


(b) QAOLFuoiγ is the Loss-Adjusted Accepted Offer Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ;

(c) QABLFuoiγ is the Loss-Adjusted Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ;

(d) QAOUNDELuoiγ is the Undelivered Accepted Offer Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ;

(e) QABUNDELuoiγ is the Undelivered Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ;

(f) QAOBIASuoiγ is the Biased Accepted Offer Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ;

(g) QABBIASuoiγ is the Biased Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ.

A.5.2.13[A.5.3.4] The Market Operator shall calculate the Imbalance Component Payment or Charge (CIMBuγ) for each Interconnector Residual Capacity Unit, u, in each Imbalance Settlement Period, γ, as follows:

CIMBuγ=PIMBγ×(∑o ∑i

(QAOLFuoiγ )+∑o∑i

(QABLFuoiγ ))where:


(b) QAOLFuoiγ is the Loss-Adjusted Accepted Offer Quantity for Interconnector Residual Capacity Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ; and

(c) QABLFuoiγ is the Loss-Adjusted Accepted Bid Quantity for Interconnector Residual Capacity Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ.

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Explanatory Note


Apply the imbalance settlement price to the correct imbalances for each interconnector related unit in the imbalance settlement period.

For the IRCU, only the instructed imbalances should be remunerated. Biased and undelivered quantities are not considered here because the party behind the IRCU, the TSO, may not be the party who caused the biased or undelivered quantity to appear. For example, biased quantities may appear due to interconnector technical constraints (IC Owner caused), or due to system constraints (TSO caused), driving the Interconnector Reference Programme to be slightly different to the Interconnector Scheduled Quantity it was intended to represent. This is why there is no subtraction of other terms in the IRCU calculation.

For the IEU, all imbalances other than the instructed imbalances should be remunerated. Therefore the instructed imbalances, accepted offers and accepted bids, are subtracted. By subtracting these terms, the imbalance charge for the IEU considers any biased quantities and undelivered quantities among the imbalances, as the following simplified version of the equation’s inputs shows:

o If QAB and QAO can be simplified as (QD – QFPN). QBIAS = QEX – QFPN, and QUNDEL = QM – QD.

o Building QAB and QAO into the imbalance component gives:

CIMB = PIMB x (QM – QEX – (QAO + QAB))

= PIMB x (QM – QEX – (QD – QFPN))

= PIMB x (QM – QD – QEX + QFPN)

= PIMB x ((QM – QD) + (QEX – QFPN))

= PIMB x (QUNDEL + QBIAS)

Therefore to fully consider bias and undelivered quantities, the IEU needs to consider these in the premium and discount component also.

A.5.2.14[A.5.3.5] The Market Operator shall calculate the Imbalance Component Payment or Charge (CIMBuγ) for each Interconnector Error Unit, u, in each Imbalance Settlement Period, γ, as follows:

CIMBuγ=PIMBγ×(QMLFuγ−QEXuγ−(∑o ∑i

(QAOLFuoiγ )+∑o∑i

(QABLFuoiγ )))where:


(b) QMLFuγ is the Loss-Adjusted Metered Quantity for Generator Unit, u, in Imbalance Settlement Period, γ;

(c) QEXuγ is the Ex-Ante Quantity for Generator Unit, u, in Imbalance Settlement Period, γ;

(d) QAOLFuoiγ is the Loss-Adjusted Accepted Offer Quantity for Interconnector Residual Capacity Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ; and

(e) QABLFuoiγ is the Loss-Adjusted Accepted Bid Quantity for Interconnector Residual Capacity Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ.

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A.6 PREMIUM AND DISCOUNT COMPONENT QUANTITIES AND PAYMENTS

Explanatory note

- Functionality for calculating volumes of energy procured in the balancing market for incs and decs for any desired period including allowing changes to PNs to substitute between balancing market volumes and intraday market volumes

- Calculating a Premium Component for Incs if the offer price for a balancing market inc BOA is greater than the imbalance settlement price

- Calculating a Discount Component for Decs if the bid price for a balancing market dec BOA is less than the imbalance settlement price

- Functionality for determining the relevant price for each BOA

A.6.1 Application to Imbalance Settlement Period and Imbalance Pricing Period

A.6.1.1 The provisions in sections A.6.2 and A.6.3 are applied to two different timeframes. For the purposes of calculating the Imbalance Price applicable to an Imbalance Pricing Period in accordance with section [on Imbalance Pricing], sections A.6.2 and A.6.3 are applied using the Imbalance Pricing Period, φ, instead of the generalised period term, h. For the purposes of calculating the settlement quantities applicable to an Imbalance Settlement Period, sections A.6.2 and A.6.3 are applied using the Imbalance Settlement Period, γ, instead of the generalised period term, h.

A.6.1.2 The provisions in this chapter will be based on the data available to the Market Operator at the time of applying those provisions to the Imbalance Pricing Period in calculating the Imbalance Price, or the time of applying those provisions to the Imbalance Settlement Period in calculating the settlement quantities, as applicable.

A.6.2 Calculation of Accepted Bid Quantities and Accepted Offer Quantities

Explanatory note

- Bid Offer Acceptances (BOAs) will be calculated for deviations between the dispatch quantity and the PN quantity.

[A.6.2.1] The Market Operator shall calculate the Accepted Offer Quantities and Accepted Bid Quantities for the purposes of the Imbalance Pricing process and for the purposes of the Settlement process, as set out in paragraphs A.6.2.3Error: Reference source not found to A.6.2.8, except in the case of an Interconnector Error Unit or an Interconnector Residual Capacity Unit, where the relevant System Operator will submit those values under paragraph A.2.5.10.

A.6.2.1[A.6.2.2]

Explanatory Note

The intention of the equations in A.6.2.3 to A.6.2.6 (inclusive) is as follows:

Parts (a) and (b) calculate the function of time version (for simplicity think of this as minute-by-minute, for all minutes within the period being considered, e.g. all minutes within a half hour Imbalance Settlement Period) of the Bid Offer Acceptance (BOA, subscript o), which is the amount the TSO is trading in the balancing market by dispatching a generator. The rest of the paragraphs show how the inputs to Parts (a) and (b) are determined for different situations. We’ll concentrate on Parts (a) and (b) first;

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This quantity needs to be split up into each generator unit, u, and each Price-Quantity (PQ) pair quantity band, i, each BOA, o, and each period, h. This is because each band, BOA, and period could have a different price depending on the timing of price data submission, the timing of acceptance of BOAs, and the different prices covering different quantity bands. So we split up the quantities in this way to ensure we can assign the correct relevant price to each unique quantity, by calculating qBOA with subscripts u, o, i and h;

The PQ information submitted could be entirely for a unit’s positive output range (i.e. putting energy onto the system), for a unit’s negative output range (i.e. taking energy from the system), or both (e.g. in the case of a pumped storage unit who can generate or consume). Part (a) is used when considering the positive output range of the unit, and Part (b) is used when considering the negative output range of the unit. i = 0 is used for output quantity = 0MW, positive i means positive output (e.g. +50MW, +70MW), negative i means negative output (unit would be consuming, e.g. -20MW, -100MW);

Parts (a) and (b) have two lines (top and bottom):

- The top line is intended to follow the dispatch curve relevant for the current BOA, o, being considered, when relevant for the band, i, being considered. At all points in time (i.e. going along each minute within the half hour). It follows the boundary of the previous band, until the latest dispatch curve has a value within the band. Then it follows the dispatch curve, until it reaches the boundary of the current band. Then it just continues out following the boundary of the current band until the end of the period.

- The bottom line is intended to follow the previous dispatch curve, the one relevant before the current BOA, o. Similarly it only considers this curve when it has values within the band in question – otherwise it follows the band boundaries.

- The difference between the current dispatch curve, and the previous dispatch curve, (i.e. subtracting the bottom line from the top line) is the quantity traded by the TSO due to BOA, o. Limiting these curves to the values relevant for each band, i, means we are splitting up this quantity into each band, so we can directly assign a unique price, the price for that quantity band, to each quantity calculated.

Parts (a) and (b) can calculate positive quantities (incs) and negative quantities (decs) at the same time, because it is a function of time (e.g. for the one qBOA, in minutes 1-7 the quantities may be positive, and then in minutes 8-29 the quantities may be negative). The inputs to the equations are different depending on whether positive quantities or negative quantities are being calculated. Because of this, the calculations for qBOA need to be carried out twice: once using the inputs for positive quantities, and again using the inputs for negative quantities. This results in two quantities for qBOA:

- qBOA using the conditions for incs; and

- qBOA using the conditions for decs

These different inputs are stated in the other paragraphs:

- For the qBOA calculation to get positive quantities, the conditions stated in the paragraph for incs are used:

o The first line of these conditions determines what is used on the top lines of (a) and (b), i.e. what dispatch curve to follow. This should be the higher of the dispatch quantity, as determined through the Instruction Profiling Process, for the relevant BOA in question, o, or the previous dispatch curve which was relevant prior to the current BOA. This adjustment is made to ensure quantities are only calculated when the dispatch quantity for order o is at a higher position than the dispatch curve prior to order o, because when this is the case, it would result in positive quantities.

o The second line of these conditions determines what is used on the bottom lines of (a) and (b), i.e. what previous dispatch curve to follow. In this case, it is the dispatch quantity for the previous order resulting from the instruction profiling process. This might not seem important in this particular case, but in other equations using this formulation qDA for the previous order could be adjusted, e.g. taking the max of the quantity

28

from Instruction Profiling or something else.

o The third of these lines defines what is to be used when we are calculating for the first order in the period, o = 1. Since we are referring to the values for previous orders on the bottom line of part (a) and (b), (o - 1) = 0 in this case, i.e. there is no previous order. This line sets the default, that for the 0th case, the relevant quantity to reference is the Final Physical Notification, FPN. This means for the first order in a period, we are comparing the dispatch curve with the FPN curve (the differences between FPN and dispatch are by definition balancing market actions), and for each subsequent order in a period we reference the previous dispatch curve rather than FPN (so we can calculate what extra balancing market volume resulted due to the extra order).

o The fourth and fifth of these lines similarly define what is the 0th case, this time for the PQ bands we are using to split up the volumes. We want to calculate for all bands submitted by a unit, i.e. i = 1, 2, 3, or i = -1, -2, -3, but we refer to the previous band value also, (i – 1) or (i + 1), so that we can calculate only values within the current band’s range (between the previous band’s upper range and current band’s upper range). This is to ensure that when we are calculating values in the bands i = 1 or i = -1, when we refer to the previous one ((i – 1) when discussing i = 1, or (i + 1) when discussing i = -1) that the range value we are taking for i = 0 is 0MW. This is to have a clean split between positive output ranges (i > 0) and negative output ranges (i < 0) when both exist, or when only one exists, providing the 0th case to ensure the algebra works when calculating for the first band.

- For the qBOA calculation to get negative quantities, the conditions stated in the paragraph for decs are used:

o The first line of these conditions is similar to the first line in the conditions for incs explained above, finding the dispatch curve to follow. In this case we take the minimum of the previous curve or the dispatch quantity from instruction profiling, because negative values will only be calculated if the dispatch quantity is lower than the previous curve;

o The second line is for the same reasons as incs;

o The third of these lines similarly defines what is to be used for first BOA where there is no previous dispatch curve for an order to reference. In this case, instead of only referencing the FPN like for positive quantities under the paragraph for incs, is takes the minimum of the FPN curve and the Outturn Availability curve. This is to make sure cases where an action taken in the balancing market due to a reduction in availability is not seen as accepting a bid, but is rather an imbalance. For example, if a unit trips, their FPN would remain unchanged, their availability would drop to 0, and the TSO would dispatch the unit down to 0 to match their availability (resulting in a dispatch quantity, qD). If availability wasn’t included in this line, this action would be calculated as the TSO accepting a Bid from the unit who tripped, but this is not correct: it should only appear as an imbalance, without any quantity calculated. Therefore we take the min of the availability quantity and the FPN quantity: if the action is due to a change in availability, no quantity should be calculated, so the top line in Part (a) or (b) would be a dispatch curve, and the bottom line of part (a) or (b) would reference the availability curve, both of these should be equal, meaning no quantity calculated.

The fourth and fifth lines are for the same reasons as the paragraphs for incs.

A.6.2.2[A.6.2.3] The Market Operator shall calculate two values for the Accepted Bid Offer Quantity (qBOAuoih(t)) as a function of time, for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in period, h, calculating separately one value for all Incs resulting from the Bid Offer Acceptance and one value for all Decs resulting from the Bid Offer Acceptance, as follows:

(a) For i > 0

29

qBOAuoih ( t )=Max {Min {qDAuoh ( t ) , qBOURuih ( t ) } , qBOURu ( i−1 ) h ( t ) }−Max {Min {qDAu (o−1 )h (t ) , qBOURuih ( t ) } , qBOURu (i−1 )h ( t ) }

(b) For i < 0:

qBOAuoih ( t )=Min {Max {qDAuoh ( t ) , qBOLRuih (t ) } , qBOLRu (i+1)h ( t ) }−Min {Max {qDAu (o−1)h (t ) , qBOLRuih ( t ) } , qBOLRu (i+1)h ( t ) }

A.6.2.3[A.6.2.4] When calculating the value for the Accepted Bid Offer Quantity (qBOAuoih(t)) for the Incs resulting from the Bid Offer Acceptance, the Market Operator shall calculate the relevant variables as follows:

qDAuoh (t )=Max (qDuoh ( t ) , qDAu (o−1)h ( t ) )

qDAu ( o−1) h ( t )=qDu (o−1 )h ( t )

qDu (o=0) h (t )=qFPN uh (t )

qBOURu ( i=0)h (t )=0

qBOLRu (i=0) h ( t )=0

A.6.2.4[A.6.2.5] When calculating the value for the Accepted Bid Offer Quantity (qBOAuoih(t)) for the Decs resulting from the Bid Offer Acceptance, the Market Operator shall calculate the relevant variables as follows:

qDAuoh (t )=Min (qDuoh (t ) , qDAu (o−1)h ( t ) )

qDAu ( o−1) h ( t )=qDu (o−1 )h ( t )

qDu (o=0)h ( t )=Min (qFPNuh ( t ) , qAVAILOuh ( t ) )

qBOURu ( i=0)h (t )=0

qBOLRu (i=0) h ( t )=0

A.6.2.5[A.6.2.6] For the purposes of paragraphs A.6.2.3 to A.6.2.5:

(a) qDuoh(t) is the Dispatch Quantity as a function of time for Generator Unit, u, for Bid Offer Acceptance, o, in period, h;

(b) qDAuoh(t) is the Adjusted Dispatch Quantity as a function of time for Generator Unit, u, for Bid Offer Acceptance, o, in period, h;

(c) qBOURuih(t) is the Bid Offer Upper Range Quantity as a function of time for Generator Unit, u, for Band, i, in period, h;

(d) qBOLRuih(t) is the Bid Offer Lower Range Quantity as a function of time for Generator Unit, u, for Band, i, in period, h;

30

(e) qFPNuh(t) is the Final Physical Notification Quantity as a function of time for Generator Unit, u, in period, h;

(f) qAVAILOuh(t) is the Outturn Availability Quantity as a function of time for Generator Unit, u, in period, h;

(g) (o – 1) is for the previous Bid Offer Acceptance in respect of the same period, h.

(h) (i – 1) is for the previous Band when considering Bands in the positive direction (i > 0);

(i) (i + 1) is for the previous Band when considering Bands in the negative direction (i < 0);

(j) (o = 0) or (i = 0) is for the 0th value for the relevant aspect (i.e. the implicit default value before an explicit Bid Offer Acceptance, o; the value for Band, i, where i = 0).

Explanatory Note

The intention of the equations below is as follows:

In the previous step, qBOA was calculated containing both positive and negative values in different minutes. It was also calculated twice: one time each with the inputs for incs and inputs for decs. These equations split out the negatives and the positives (positives from max of the value in each minute and zero, negatives from min of the value and zero), from the relevant calculation (for positive values, we care about the inputs for incs, for negative values, we care about the inputs for decs).

A.6.2.6[A.6.2.7] The Market Operator shall calculate the Accepted Offer Quantity (qAOuoih(t)) as a function of time, and the Accepted Bid Quantity (qABuoih(t)) as a function of time, for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in period, h, separately for the Incs and Decs, as follows:

qAOuoih (t )=Max (qBOAuoih (t ) for Incs ,0 )

qABuoih( t)=Min (qBOAuoih ( t ) for Decs ,0 )

where:

(a) qBOAuoih(t) is the Accepted Bid Offer Quantity as a function of time for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in period, h.

Explanatory Note

The intention of the paragraph below is as follows:

- Because everything so far has been done as a function of time granularity (minute-by-minute), but settlement and pricing are done at a period granularity (5 minutes, 30 minutes), the function of time results need to be converted into period results by integrating the values of the function of time curves over the period in question.

A.6.2.7[A.6.2.8] The Market Operator shall calculate the Accepted Offer Quantity (QAOuoih) and the Accepted Bid Quantity (QABuoih) for Generator Unit u, in period h, by integrating the associated function of time Accepted Offer Quantity (qAOuoih(t)) and Accepted Bid Quantity (qABuoih(t)) with respect to time across the period, h.

31

A.6.3 Determination of Accepted Bid and Accepted Offer PricesA.6.3.1 Except in the case of an Interconnector Error Unit or an Interconnector

Residual Capacity Unit, the Bid Offer Price (PBOuβoih) for each Accepted Bid Quantity and each Accepted Offer Quantity shall be:

[(a)] For each Accepted Offer Quantity, QAOuoih, the iIncremental pPrice in the Band, i, provided in the relevant Commercial Offer Data set as determined in section A.3.2;

[(b)] For each Accepted Bid Quantity, QABuoih, the dDecremental pPrice in the Band, i, provided in the relevant Commercial Offer Data set as determined in section A.3.2.

[A.6.3.2] The Bid Offer Price (PBOuβoih) for each individual Accepted Bid Quantity and Accepted Offer Quantity, for each Bid Offer Acceptance, o, relevant to an Interconnector Residual Capacity Unit, u, shall be the values submitted by the System Operator for the relevant Interconnector, l, in accordance with paragraph A.2.5.10.

A.6.4 Calculation of Trade in the Opposite Direction to the TSO Quantities

Explanatory notes

- If a change in PN constitutes a trade in the opposite direction to the TSO – The volume to which the premium/discount is attributed should not include the volume which arises from this change;

- Calculate the volume arising through PN changes which result in an increase to the volume of a balancing market order (“Trade in the Opposite Direction to the TSO”)

- Remove the volume from Trade in the Opposite Direction to the TSO from the premium or discount component

Explanatory Note

The intention of the equations in these equations is as follows:

- The format of these equations is similar to qBOA. This is intentional: both of these calculate volumes in the same manner. qBOAWTOTSO has a few tweaks which makes it different:

o At its simplest, TOTSO is where the FPN is in a position versus the PN at the time of accepting the order such that it increases the volume of the order. E.g. if an inc order was accepted of 100MWh with PN1, but then the value when calculated with the FPN was 150MWh, it means the FPN was decreased versus PN1 to increase the volume of the order by 50MWh.

o Parts (a) and (b) are the same as for qBOAs, subtracting the current dispatch quantity (top line) from the previous dispatch quantity (bottom line), while splitting up by band, period, and BOA;

o In the conditions for incs and decs, a tweak is made where instead of the second line being qDA(o-1) = qD(o-1), there are new rules around which values we want to use in the previous dispatch quantity in order to exclude all values which are due to trade opposite TSO.

o The third line outlines some of these new rules through qDAWTOTSO(o-1). The intention is to follow the previous dispatch quantity, qD(o-1), calculating qBOAs like normal, unless it crosses the quantity of the PN which was present at the time (beta) of accepting order (o-1) (qD(o-1) crossing to below this PNbeta(o-1) for incs, and qD(o-1) crossing to above this PNbeta(o-1) for decs). When this crossing occurs, we need to reference the 0th case, qD(0), to see what quantity to follow. We care about this “crossing” point because it determines if the relationship between the PN at the time of the order acceptance and the FPN, and isolates where TOTSO might be occurring for one order but not for another in the same period (e.g. order (o-1) might have

32

TOTSO applied, but order o might not – might need to refer to FPN quantity for order o like a normal qBOA, while referring to the PNbeta(o-1) quantity for order (o-1)).

o The fourth and fifth lines of these equations set out the different rules for the 0th case for excluding TOTSO volumes, determining whether for the previous dispatch quantity to use in parts (a) and (b) we should:

Follow the PNbeta(o) quantity to make sure we exclude TOTSO volumes, if the PNbeta(o) quantity is different to the FPN quantity or;

Follow the FPN quantity like a normal qBOA, because the relationship between the PN at the time of acceptance and the FPN is such that there is no volume due to TOTSO.

We only care about this tweak when the current dispatch quantity, qDAo, is greater than qPNbeta(o) for incs, or less than qPNbeta(o) for decs, because when the opposite of these cases occur, it is not considered volume due to TOTSO, it is considered volume where an initial inc was switched to a dec, or vice versa, which is not intended to be excluded as part of this formulation.

o The 6th and 7th lines of the conditions for incs and decs are the same as for qBOA

Without Trade Opposite TSO

These equations calculate the volume of the accepted bid/offer quantity that is left after volumes due to trades entered into in the opposite direction to the TSO’s dispatch instruction (this is what is meant by quantity “without trade opposite TSO”).

A.6.4.1 Where the Regulatory Authorities have given notice to the Market Operator of a requirement to include QAOTOTSOuoiγ and QABTOTSOuoiγ in the calculation of Premium and Discount Component Payments, the Market Operator shall, from the time the notice takes effect, calculate QAOTOTSOuoiγ and QABTOTSOuoiγ in accordance with the procedure set out in paragraphs A.6.4.5 to A.6.4.11.

A.6.4.2 Where the Regulatory Authorities have not given a notice under paragraph A.6.4.1, or have withdrawn a notice under that paragraph, the Market Operator shall set the values of QAOTOTSOuoiγ and QABTOTSOuoiγ to zero.

[A.6.4.3] A notice under paragraph A.6.4.1, or a withdrawal under that paragraph, shall takes effect at the beginning of the Trading Day onwhich is the later of:

[(a)] The timeThat specified in the notice or withdrawal; and

(a)[(b)] The expiration of [two months] after the notice was received by the Market Operator.

[A.6.4.4] Following receipt of a notice or withdrawal of a notice byIf the Regulatory Authorities give a notice under paragraph A.6.4.1 or withdrawal under that paragraph, the [Market Operator] shall promptly publish such notice or notice of withdrawalit.

A.6.4.3[A.6.4.5] The Market Operator shall calculate two values for the Without Trade Opposite TSO Accepted Bid Offer Quantity (qBOAWTOTSOuoiγ(t)) as a function of time, for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in period, h, calculating separately one value for all Incs resulting from the Bid Offer Acceptance and one value for all Decs resulting from the Bid Offer Acceptance, as follows:

(a) For i > 0:

qBOAWTOTSOuoiγ (t )=Max {Min {qDAuoγ (t ) ,qBOUR uiγ ( t ) } , qBOURu (i−1) γ (t ) }−Max {Min {qDAu ( o−1) γ ( t ) , qBOURuiγ ( t ) } , qBOURu (i−1)γ ( t ) }33

(b) For i < 0:

qBOAWTOTSOuoiγ (t )=Min {Max {qDAuoγ (t ) ,qBOLRuiγ (t ) } , qBOLRu ( i+1 ) γ ( t ) }−Min {Max {qDA u (o−1) γ ( t ) , qBOLRuiγ (t ) }, qBOLRu (i+1)γ (t ) }

A.6.4.4[A.6.4.6] When calculating the value for the Without Trade Opposite TSO Accepted Bid Offer Quantity (qBOAWTOTSOuoiγ(t)) for the Incs resulting from the Bid Offer Acceptance, the Market Operator shall calculate the relevant variables as follows:

qDAuoγ ( t )=Max (qDuoγ ( t ) ,qDA u (o−1) γ (t ) )

qDAu (o−1)γ (t)=qDAWTOTSOu (o−1)γ (t)

If qDu (o−1) γ (t )≥qPN uβ ( o−1) γ ( t ) ,thenqDAWTOTSOu (o−1 )γ ( t )=qDu (o−1)γ ( t )elseqDAWTOTSOu (o−1 )γ ( t )=qDu ( o=0) γ (t )

qDu (o=0)γ (t)=qDWTOTSOu (o=0)γ (t)

If qDuoγ (t )≥qPN uβoγ (t ) , thenqDWTOTSOu (o=0 ) γ ( t )=Max (qPN uβoγ ( t ) , qFPN uγ ( t ) )elseqDWTOTSOu (o=0 ) γ ( t )=qFPN uγ (t )

qPN uβ ( o=0) γ ( t )=0

qBOURu ( i=0) γ ( t )=0

qBOLRu (i=0) γ ( t )=0

A.6.4.5[A.6.4.7] When calculating the value for the Without Trade Opposite TSO Accepted Bid Offer Quantity (qBOAWTOTSOuoiγ(t)) for the Decs resulting from the Bid Offer Acceptance, the Market Operator shall calculate the relevant variables as follows:

qDAuoγ ( t )=Min (qDuoγ ( t ) , qDAu ( o−1) γ (t ) )

qDAu (o−1)γ (t)=qDAWTOTSOu (o−1)γ (t)

If qDu (o−1) γ (t )≤qPN uβ ( o−1) γ ( t ) ,thenqDAWTOTSOu ( o−1) γ ( t )=qDu ( o−1) γ ( t )elseqDAWTOTSOu ( o−1) γ ( t )=qDu ( o=0) γ ( t )

34

qDu (o=0)γ (t)=qDWTOTSOu (o=0)γ (t)

If qDuoγ (t )≤qPN uβoγ (t ) , thenqDWTOTSOu (o=0 ) γ ( t )=Min (qPN uβoγ ( t ) , qFPN uγ (t ) , qAVAILOuγ (t ) )elseq DWTOTSOu (o=0) γ (t )=Min (qFPN uγ ( t ) , qAVAILOuγ (t ) )

qPN uβ ( o=0) γ ( t )=0

qBOURu ( i=0) γ (t )=0


A.6.4.6[A.6.4.8] For the purposes of paragraphs A.6.4.5 to A.6.4.7:

(a) qDuoγ(t) is the Dispatch Quantity as a function of time for Generator Unit, u, for Bid Offer Acceptance, o, in Imbalance Settlement Period, γ;

(b) qDAuoγ(t) is the Adjusted Dispatch Quantity as a function of time for Generator Unit, u, for Bid Offer Acceptance, o, in Imbalance Settlement Period, γ;

(c) qDWTOTSOuoγ(t) is the Without Trade Opposite TSO Dispatch Quantity as a function of time for Generator Unit, u, for Bid Offer Acceptance, o, in Imbalance Settlement Period, γ;

(d) qDAWTOTSOuoγ(t) is the Without Trade Opposite TSO Adjusted Dispatch Quantity as a function of time for Generator Unit, u, for Bid Offer Acceptance, o, in Imbalance Settlement Period, γ;

(e) qBOURuiγ(t) is the Bid Offer Upper Range Quantity as a function of time for Generator Unit, u, for Band, i, in Imbalance Settlement Period, γ;

(f) qBOLRuiγ(t) is the Bid Offer Lower Range Quantity as a function of time for Generator Unit, u, for Band, i, in Imbalance Settlement Period, γ;

(g) qFPNuγ(t) is the Final Physical Notification Quantity as a function of time for Generator Unit, u, in Imbalance Settlement Period, γ;

(h) qPNuβoγ(t) is the Physical Notification Quantity as a function of time for Generator Unit, u, time stamped, β, as the last one submitted by the relevant Participant before Bid Offer Acceptance, o, in Imbalance Settlement Period, γ;

(i) qAVAILOuγ(t) is the Outturn Availability Quantity as a function of time for Generator Unit, u, in Imbalance Settlement Period, γ;

(j) (o – 1) is for the previous Bid Offer Acceptance for the unit;

(k) (i – 1) is for the previous Band when considering Bands in the positive direction (i > 0);

(l) (i + 1) is for the previous Band when considering Bands in the negative direction (i < 0);

35

(m) (o = 0) or (i = 0) is for the 0th value for the relevant aspect (i.e. the implicit default value before an explicit Bid Offer Acceptance, o; the value for Band, i, where i = 0).

A.6.4.7[A.6.4.9] The Market Operator shall calculate the Without Trade Opposite TSO Accepted Offer Quantity (qAOWTOTSOuoiγ(t)) as a function of time, and the Without Trade Opposite TSO Accepted Bid Quantity (qABWTOTSOuoiγ(t)) as a function of time, for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement Period, γ, as follows:

qAOWTOTSOuoiγ ( t )=Max (qBOAWTOTSOuoiγ ( t ) for Incs ,0 )

qABWTOTSOuoiγ (t)=Min (qBOAWTOTSOuoiγ ( t ) for Dec s ,0)

where:

(a) qBOAWTOTSOuoiγ(t) is the Without Trade Opposite TSO Accepted Bid Offer Quantity as a function of time for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ.

Explanatory Note


- The previous calculations work out a volume which is qBOA but excluding volumes due to TOTSO. To find the volumes due to TOTSO, this can be subtracted from the actual qBOA.

A.6.4.8[A.6.4.10] The Market Operator shall calculate the Trade Opposite TSO Accepted Offer Quantity (qAOTOTSOuoiγ(t)) as a function of time, and the Trade Opposite TSO Accepted Bid Quantity (qABTOTSOuoiγ(t)) as a function of time, for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement Period, γ, as follows:

qAOTOTSOuoiγ (t )=Max (qAOuoiγ ( t )−qAOWTOTSOuoiγ ( t ) ,0 )

qABTOTSOuoiγ( t )=Min (qABuoiγ ( t )−qABWTOTSOuoiγ ( t ) ,0 )

where:

(a) qAOuoiγ(t) is the Accepted Offer Quantity as a function of time for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ;

(b) qABuoiγ(t) is the Accepted Bid Quantity as a function of time for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ;

(c) qAOWTOTSOuoiγ(t) is the Without Trade Opposite TSO Accepted Offer Quantity as a function of time for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ; and

(d) qABWTOTSOuoiγ(t) is the Without Trade Opposite TSO Accepted Bid Quantity as a function of time for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ.

36

A.6.4.9[A.6.4.11] The Market Operator shall calculate the Trade Opposite TSO Accepted Offer Quantity (QAOTOTSOuoiγ), and the Trade Opposite TSO Accepted Bid Quantity (QABTOTSOuoiγ), for Generator Unit u, for the Imbalance Settlement Period, γ, by integrating the associated function of time quantities Trade Opposite TSO Accepted Offer Quantity (qAOTOTSOuoiγ(t)) and Trade Opposite TSO Accepted Bid Quantity (qABTOTSOuoiγ(t)) with respect to time across the Imbalance Settlement Period, γ.

A.6.4.10[A.6.4.12] The provisions of section A.6.4 do not apply to an Interconnector Error Unit or Interconnector Residual Capacity Unit.

A.6.5 Calculation of Non-Firm Decremental Quantities

Explanatory notes:

- If a dec bid was accepted from a participant within their non-firm capacity range – the volume to which the premium/discount is attributed should not include this component of the volume;

- Functionality for determining the situations when the calculations for non-firm constraints are needed.

- Calculate the volume if a dec balancing market action occurring over the non-firm output range of a unit when the situation requires this calculation.

- Remove this non-firm volume from the discount component.

A.6.5.1 The Market Operator shall determine the Firm Access Quantity (qFAQuγ(t)) as a function of time for each Generator Unit, u, in Trading Site, s, with Non-Firm Access in Imbalance Settlement Period, γ, as follows:

Note: intention of the equations are as follows:

- Similar to a current provision in the TSC, because firm access is assigned to trading sites rather than units, in cases where there is non-firm access on a trading site there needs to be some rationale to split how much firmness each unit on the site has. This rationale is based on how much decremental bids have been accepted on the unit, because firmness only affects the settlement of these orders

- The first line works out how much non-firmness there is on the site, i.e. how much in net does generation and demand on the site intend to be on the system above its firm access quantity. Because metered demand (QMvgamma) can only be at an integrated settlement period granularity, this equation is carried out to that granularity.

- The next line assigns this non-firmness to units pro-rata based on how much of the overall site decremental orders they received, so that the unit with the most dec orders gets most of the non-firmness. It assumes that a unit is initially firm up to its FPN, and then decreases this firmness by the allotted amount of non-firmness. Because the intended result is a function-of-time MW result, while the equations are being carried out on an integrated period MWh level, it needs to be divided by the period (in hours) in question, the imbalance settlement period (0.5 hours) to get the MW result.]

QFPNNF sγ=Max (∑us QFPNuγ+∑v s QM vγ−QFAQ sγ ,0)If∑

us∑o∑iQABuoiγ<0 ,then

37

qFAQuγ (t )=

Max(QFPN uγ−QFPNNF sγ( ∑o∑iQABuoiγ

∑u s

∑o∑iQABuoiγ ) ,0)

DISPElse

qFAQuγ (t )=QFPN uγDISP

where:

(a) QFPNNFsγ is the Non-Firm Final Physical Notification Quantity for Trading Site, s, in Imbalance Settlement Period, γ;

(b) QFPNuγ is the Final Physical Notification Quantity for Generator Unit, u, in Imbalance Settlement Period, γ;

(c) QMvγ is the Metered Quantity for Supplier Unit, v, in Imbalance Settlement Period, γ;

(d) QFAQsγ is the Firm Access Quantity for Trading Site, s, in Imbalance Settlement Period, γ;

(e) QABuoiγ is the Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ;

(f) ∑v s

means the value for the single Supplier Unit, v, in Trading Site, s,

in accordance with [paragraph in registration stating that Trading Sites may only have a single Supplier Unit]; and

(g) DISP is the Imbalance Settlement Period Duration.

A.6.5.2 The Market Operator shall calculate the value of the Non-Firm Accepted Bid Offer Quantity (qBOANFuoiγ(t)) as a function of time, for each Generator Unit, u, for all Decs resulting from each Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement Period, γ, as follows:

Note: the intention of these equations are as follows:

- A similar formulation to a normal qBOA calculation but with tweaks to calculate only those dec volumes which are non-firm. Parts (a) and (b) of this equation are the same as for qBOA and only the inputs for decs are needed;

- The tweaks come the conditions for decs, where in order to calculate those volumes which were non-firm (i.e. all dec volumes for where the FPN quantity is higher than the firmness quantity calculated in the previous section), the second line (for qDANF) is adjusted to take the maximum of the current dispatch quantity and the firm access quantity. This means that it will only calculate those parts of the dec bid accepted which were above the FAQ, following the FAQ quantity when the dispatch quantity goes below it. All other lines are the same as for qBOA.

(a) For i > 0:

qBOANF uoiγ ( t )=Max {Min {qDAuoγ ( t ) , qBOURuiγ ( t ) } ,qBOUR u( i−1) γ ( t ) }−Max {Min {qDAu (o−1 ) γ (t ) ,qBOURuiγ ( t ) }, qBOURu(i−1)γ (t ) }

(b) For i < 0:

38

qBOANF uoiγ ( t )=Min {Max {qDAuoγ ( t ) , qBOLRuiγ ( t ) } , qBOLRu (i+1) γ (t ) }−Min {Max {qDAu (o−1) γ (t ) , qBOLRuiγ (t ) } , qBOLRu(i+1) γ (t ) }

A.6.5.3 When calculating the value for the qBOANFuoiγ(t), the Market Operator shall calculate the relevant variables as follows:

qDAuoγ ( t )=qDANF uoγ ( t )

qDANFuoγ (t )=Min (Max (qDuoγ (t ) , qFAQuγ ( t ) ) , qDAu (o−1 ) γ ( t ))

qDAu ( o−1) γ ( t )=qDu (o−1 ) γ ( t )

qDu ( o=0) γ ( t )=Min (qFPN uγ (t ) ,qAVAILOuγ (t ) )

qBOURu ( i=0) γ (t )=0


A.6.5.4 For the purposes of paragraphs A.6.5.1 to A.6.5.3:



(c) qDANFuoγ(t) is the Non-Firm Adjusted Dispatch Quantity as a function of time for Generator Unit, u, for Bid Offer Acceptance, o, in Imbalance Settlement Period, γ;

(d) qFAQuγ(t) is the Firm Access Quantity as a function of time for Generator Unit, u, in Imbalance Settlement Period, γ;

(e) qBOURuiγ(t) is the Bid Offer Upper Range Quantity as a function of time for Generator Unit, u, for Band, i, in Imbalance Settlement Period, γ;

(f) qBOLRuiγ(t) is the Bid Offer Lower Range Quantity as a function of time for Generator Unit, u, for Band, i, in Imbalance Settlement Period, γ;

(g) qFPNuγ(t) is the Final Physical Notification Quantity as a function of time for Generator Unit, u, in Imbalance Settlement Period, γ;

(h) qAVAILOuγ(t) is the Outturn Availability Quantity as a function of time for Generator Unit, u, in Imbalance Settlement Period, γ;

(i) (o – 1) is for the previous Bid Offer Acceptance.

(j) (i – 1) is for the previous Band when considering Bands in the positive direction (i > 0);

(k) (i + 1) is for the previous Band when considering Bands in the negative direction (i < 0);

39

(l) (o = 0) or (i = 0) is for the 0th value for the relevant aspect (i.e. the implicit default value before an explicit Bid Offer Acceptance, o; the value for Band, i, where i = 0).

A.6.5.5 The Market Operator shall calculate the Non-Firm Accepted Bid Quantity (qABNFuoiγ(t)) as a function of time, for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement Period, γ, as follows:

qABNFuoiγ (t )=Min (qBOANF uoiγ (t ) ,0 )

where:

(a) qBOANFuoiγ(t) is the Non-Firm Accepted Bid Offer Quantity as a function of time for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ.

[A.6.5.6] The Market Operator shall calculate the Non-Firm Accepted Bid Quantity (QABNFuoiγ) as an integrated quantity for the Imbalance Settlement Period γ, for Generator Unit u, for Bid Offer Acceptance, o, for Band, i, for the Imbalance Settlement Period, γ, by integrating the the associated function of time the quantity Non-Firm Accepted Bid Quantity (qABNFuoiγ(t)) with respect to time across the Imbalance Settlement Period, γ.

A.6.5.6[A.6.5.7] The provisions in section A.6.5 do not apply to an Interconnector Error Unit or Interconnector Residual Capacity Unit.

A.6.6 Calculation of Undelivered Quantities

Explanatory notes:

- If a participant’s metered generation shows that they did not deliver their balancing market order according to their dispatched quantity – the volume to which the premium/discount is attributed should not include this undelivered volume;

- Calculate the uninstructed imbalance volume on a unit for a period (different than the imbalance component which includes instructed imbalances, this is the difference between what the unit was instructed to do, and what they delivered).

- Determine, from the orders accepted and the uninstructed imbalance volume on the unit, the volume of the accepted orders, in whole or a fraction, which were not delivered (i.e. for over-delivery, decs deemed not to have been delivered, for under-delivery, incs deemed not to have been delivered).

- Remove these volumes from the premium or discount component.

Explanatory Note

The intention of the equation below is as follows:

- Calculate the total undelivered quantity, which is the difference between what the unit was dispatched to do (QD) and what it actually did (QM). If this value is negative, it means that QM was below QD, meaning it should have delivered more: therefore inc offers may not have been delivered. If this value is positive, it means that QM was above QD, meaning it should have delivered less: therefore dec bids may not have been delivered.

A.6.6.1 The Market Operator shall calculate the Undelivered Quantity (QUNDELuγ) for each Generator Unit, u, in Imbalance Settlement Period, γ, as follows:

40

QUNDELuγ=QMLFuγ−QDLFuγ

where:

(a) QMLFuγ is the Loss-Adjusted Metered Quantity for Generator Unit, u, in Imbalance Settlement Period, γ;

(b) QDLFuγ is the Loss-Adjusted Dispatch Quantity for the Generator unit, u, in Imbalance Settlement Period, γ.

A.6.6.2 Where the Undelivered Quantity has a positive value, the Market Operator shall determine which of the Accepted Bid Quantities were not delivered, in whole or in part, for each Generator Unit, u, in Imbalance Settlement Period, γ, in accordance with paragraphs A.6.6.3 to A.6.6.5.

A.6.6.3 The Market Operator shall derive a ranked set of all Accepted Bid Quantities for Generator Unit, u, in Imbalance Settlement Period, γ, in order of increasing price. The Accepted Bid Quantity with the lowest price will be allocated a rank number n = 1, the next lowest priced Accepted Bid Quantity a rank number n = 2 and so on until all Accepted Bid Quantities have been allocated a rank number. Where two or more Accepted Bid Quantities have equal prices, they shall be ranked using a systematic process of random selection which may include making small alterations to the submitted prices. Any such amended prices will only be used for this purpose in the ranking process.

Explanatory Note


- In the first paragraph of this section, the total undelivered amount was calculated. These equations are intended to overlay the total undelivered amount onto a stack of the accepted bids to determine which of them were not delivered. It looks at each bid in the stack, in price order.

- If the volume of the undelivered quantity remaining to assign is larger than the volume of the accepted bid being considered, it determines that all of that accepted bid volume is undelivered. This is done in the first equation.

- The second equation then reduces the volume of the undelivered quantity remaining to assign after the assignment for the current order.

- These two equations continue to be used for each bid in the stack in order, until the last amount of the remaining undelivered quantity has been assigned: this is done firstly in the first equation where the smaller volume of the bid or the remaining undelivered is taken (small as in both of these should be negative quantities, therefore the smallest negative quantity, the max, should be taken), this would be like saying a bid quantity was partially undelivered. The second equation then reduces the amount of remaining undelivered to zero or a negative number, such that where it to be used for the next bid in the stack, the result of the first equation would be zero.

- The third line is an input to the process: for the first bid in the stack being considered, all of the undelivered volume calculated earlier is remaining to be assigned.

[A.6.6.4] The Market Operator shall calculate the Undelivered Accepted Bid Quantity (QABUNDELuoiγn) for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in ascending order of each position, n, in the ranked set , in Imbalance Settlement Period, γ, as follows:

41

QABUNDELuoiγn=Min (Max (QABLF uoiγn ,−QUNDELRuγ ( n−1) ) ,0)

QUNDELRuγn=QUNDELRuγ (n−1)+QABUNDELuoiγn

QUNDELRuγ (n=0)=QUNDELuγ

This is done in ascending order of each position, n, in the ranked set .

where:

(a) QABLFuoiγn is the Loss-Adjusted Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in the ranked set at rank, n, in Imbalance Settlement Period, γ;

(b) QUNDELRuγn is the Remaining Undelivered Quantity for Generator Unit, u, for the calculations in the ranked set at rank, n, in Imbalance Settlement Period, γ;

(c) QUNDELuγ is the Undelivered Quantity for Generator Unit, u, in Imbalance Settlement Period, γ.

(d) (n – 1) is for the previous item in the ranked set; and

(e) (n = 0) is for the 0th item in the ranked set, i.e. where a calculation is being performed on the first item in the ranked set, (n = 1), for which there is no previous item.

Explanatory Note


- Since the previous paragraph needed to work on bids in a certain order, subscript n was used to determine that order. This ordering is not important for the remaining settlement processes, so the value of the undelivered portion of accepted bid quantity for GU, u, for BOA, o, in band, i, in period, gamma, is the same as the value determined for the same u, o, i, and gamma, with the n subscript.

A.6.6.4[A.6.6.5] The Market Operator shall calculate the Undelivered Accepted Bid Quantity (QABUNDELuoiγ) for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement Period, γ, as follows:

QABUNDELuoiγ=QABUNDELuoiγn

where:

(a) QABUNDELuoiγn is the Undelivered Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, for position in the rank set, n, in Imbalance Settlement Period, γ.

A.6.6.5[A.6.6.6] Where the Undelivered Quantity has a negative value, the Market Operator shall determine which of the Accepted Offer Quantities were not delivered, in whole or in part, for each Generator Unit, u, in Imbalance Settlement Period, γ, in accordance with paragraphs A.6.6.7 to A.6.6.9.

A.6.6.6[A.6.6.7] The Market Operator shall derive a ranked set of all Accepted Offer Quantities for Generator Unit, u, in Imbalance Settlement Period, γ, in order

42

of decreasing price. The Accepted Offer Quantity with the highest price will be allocated a rank number n = 1, the next highest priced Accepted Offer Quantity a rank number n = 2 and so on until all Accepted Offer Quantities have been allocated a rank number. Where two or more Accepted Offer Quantities have equal prices, they shall be ranked using a systematic process of random selection which may include making small alterations to the submitted prices. Any such amended prices will only be used for this purpose in the ranking process.

Explanatory Note


- This is the same as for earlier, but because of the sign of the total undelivered quantity, offers are being considered rather than bids. This changes where we are looking at max or min in the formulations: in the previous equations for decs, because in the first equation we were firstly looking for the smallest volume of the offer quantity or the remaining undelivered quantity, for decs the smallest of two negative quantities in the max, for incs the smallest of two positive quantities is the min.

A.6.6.7[A.6.6.8] The Market Operator shall calculate the Undelivered Accepted Offer Quantity (QAOUNDELuoiγn) for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in ascending order of each position, n, in the ranked set, in Imbalance Settlement Period, γ, as follows:

QAOUNDELuoiγn=Max (Min (QAOLF uoiγn ,−QUNDELRuγ (n−1 )) ,0 )

QUNDELRuγn=QUNDELRuγ (n−1)+QAOUNDELuoiγn

QUNDELRuγ ( n=0)=QUNDELuγ

This is done in ascending order of each position, n, in the ranked set.

where:

(a) QAOLFuoiγn is the Loss-Adjusted Accepted Offer Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in the ranked set at rank, n, in Imbalance Settlement Period, γ;

(b) QUNDELRuγn is the Remaining Undelivered Quantity for Generator Unit, u, for the calculations in the ranked set at rank, n, in Imbalance Settlement Period, γ;

(c) QUNDELuγ is the Undelivered Quantity for Generator Unit, u, in Imbalance Settlement Period, γ.



A.6.6.8[A.6.6.9] The Market Operator shall calculate the Undelivered Accepted Offer Quantity (QAOUNDELuoiγ) for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement Period, γ, as follows:

43

QAOUNDELuoiγ=QAOUNDELuoiγn

where:

(a) QAOUNDELuoiγn is the Undelivered Accepted Offer Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, for position in the rank set, n, in Imbalance Settlement Period, γ.

Explanatory Note

Intention of paragraphs below is as follows:

- As stated earlier, to fully consider bias and undelivered quantities, the IEU needs to consider these in the premium and discount component. This needs to be done by stating that although the biased and undelivered quantities are calculated for the ICRP (because they are the unit with the Accepted Offers and Accepted Bids, and FPN, which are used to calculate the quantities), they are taken forward through the IEU for settlement.

A.6.6.9[A.6.6.10] The provisions in paragraphs A.6.6.1 to A.6.6.9 do not apply to an Interconnector Error Unit.

A.6.6.10[A.6.6.11] The Market Operator shall:

(a) assign the Undelivered Accepted Offer Quantities and Undelivered Accepted Bid Quantities, QAOUNDELuoiγ and QABUNDELuoiγ, calculated in accordance with paragraphs A.6.6.1 to A.6.6.9 for an Interconnector Residual Capacity Unit, u, to the relevant Interconnector Error Unit, u; and

(b) set the values of the quantities referred to in paragraph (a) for the Interconnector Residual Capacity Unit to zero,

for the purposes of any processes using these quantities.

A.6.7 Calculation of Biased Quantities

Explanatory notes

- If a participant’s FPN is biased, with reference to its ex-ante position, in a direction which increases the volume to which the premium/discount is attributed (i.e. PN biased below ex-ante position for incs, above ex-ante position for decs) – the volume to which the premium/discount is attributed should not include this component of the volume. This is because the biased volume was already settled in the ex-ante markets, it was only calculated in the Balancing Market because the PN was biased versus the ex-ante position, therefore to ensure it isn’t double counted we must remove it from the balancing market volumes calculated.

- Calculate the difference between the ex-ante quantity (EAQ) of the unit and the PN which is intended to represent that position.

- Determine, from the orders accepted and the difference between the ex-ante position of the unit and the PN, if there are quantities of the accepted orders, in whole or a fraction, which result from a bias (i.e. if the PN was lower than the EAQ it was intended to represent, then some inc orders could be biased. If the PN was higher than the EAQ it was intended to represent, then some dec orders could be biased).

- Remove these volumes from the premium or discount component.

Explanatory Note

The intention of the equations in section A.6.7 is as follows:

- This is the same process as for determining which balancing market quantities, of

44

fractions of those quantities, are undelivered. It overlays the total onto a stack of orders, which are incs or decs depending on whether the bias value is positive or negative.

- The price order of the stack is different. Undelivered quantities look at prices from high to low for incs, low to high for decs, to capture those which are most “expensive” and deeming them undelivered first. This is based on logic that the quantities nearest the dispatch quantity would be most expensive, as actions are taken in order from least to most expensive and QD should be the final point of actions taken. Biased quantities look at prices from low to high for incs, high to low for decs, to capture those which are “cheapest” and deeming them biased first. This is based on the logic that the FPN is the start point for actions taken, and therefore actions nearest FPN which could be biased would be the cheapest.

A.6.7.1 The Market Operator shall calculate the Biased Quantity (QBIASuγ) for each Generator Unit, u, in Imbalance Settlement Period, γ, as follows:

QBIASuγ=QEXuγ−QFPNLF uγ

where:

(a) QEXuγ is the Ex-Ante Quantity for Generator Unit, u, in Imbalance Settlement Period, γ, as calculated under section A.5.2;

(b) QFPNLFuγ is the Loss-Adjusted Final Physical Notification Quantity for the Generator unit, u, in Imbalance Settlement Period, γ.

A.6.7.2 Where the Biased Quantity has a positive value, the Market Operator shall determine which of the Accepted Offer Quantities were biased, in whole or in part, for each Generator Unit, u, in Imbalance Settlement Period, γ, in accordance with paragraphs A.6.7.3 to A.6.7.6.

A.6.7.3 The Market Operator shall derive a ranked set of all Accepted Offer Quantities for Generator Unit, u, in Imbalance Settlement Period, γ, in order of increasing price. The Accepted Offer Quantity with the lowest price will be allocated a rank number n = 1, the next lowest priced Accepted Offer Quantity a rank number n = 2 and so on until all Accepted Offer Quantities have been allocated a rank number. Where two or more Accepted Offer Quantities have equal prices, they shall be ranked using a systematic process of random selection which may include making small alterations to the submitted prices. Any such amended prices will only be used for this purpose in the ranking process.

A.6.7.4 The Market Operator shall calculate the Biased Accepted Offer Quantity (QAOBIASuoiγn) for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in ascending order of each position, n, in the ranked set, in Imbalance Settlement Period, γ, as follows:

QAOBIASuoiγn=Max (Min (QAOLF uoiγn ,QBIASRuγ (n−1) ) ,0)

QBIASRuγn=QBIASRuγ (n−1)−QAOBIASuoiγn

QBIASRuγ (n=0 )=QBIASuγ


where:

45

(a) QAOLFuoiγn is the Loss-Adjusted Accepted Offer Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in the ranked set at rank, n, in Imbalance Settlement Period, γ;

(b) QBIASRuγn is the Remaining Biased Quantity for Generator Unit, u, for the calculations in the ranked set at rank, n, in Imbalance Settlement Period, γ;

(c) QBIASuγ is the Biased Quantity for Generator Unit, u, in Imbalance Settlement Period, γ;



A.6.7.5 The Market Operator shall calculate the Biased Accepted Offer Quantity (QAOBIASuoiγ) for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement Period, γ, as follows:

QAOBIASuoiγ=QAOBIASuoiγn

where:

(a) QAOBIASuoiγn is the Biased Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, for position in the rank set, n, in Imbalance Settlement Period, γ.

A.6.7.6 Where the Biased Quantity has a negative value, the Market Operator shall determine which of the Accepted Bid Quantities were biased, in whole or in part, for each Generator Unit, u, in Imbalance Settlement Period, γ, in accordance with paragraphs A.6.7.7 to A.6.7.9.

A.6.7.7 The Market Operator shall derive a ranked set of all Accepted Bid Quantities for Generator Unit, u, in Imbalance Settlement Period, γ, in order of decreasing price. The Accepted Bid Quantity with the highest price will be allocated a rank number n = 1, the next highest priced Accepted Bid Quantity a rank number n = 2 and so on until all Accepted Bid Quantities have been allocated a rank number. Where two or more Accepted Bid Quantities have equal prices, they shall be ranked using a systematic process of random selection which may include making small alterations to the submitted prices. Any such amended prices will only be used for this purpose in the ranking process.

A.6.7.8 The Market Operator shall calculate the Biased Accepted Bid Quantity (QABBIASuoiγn) for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in ascending order of each position, n, in the ranked set, in Imbalance Settlement Period, γ, as follows:

QABBIASuoiγn=Min (Max (QABLF uoiγn ,QBIASRuγ (n−1) ) ,0 )

QBIASRuγn=Q BIASRuγ (n−1 )−QABBIASuoiγn

QBIASRuγ (n=0 )=QBIASuγ

46


where:

(a) QABLFuoiγn is the Loss-Adjusted Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in the ranked set at rank, n, in Imbalance Settlement Period, γ;

(b) QBIASRuγn is the Remaining Biased Quantity for Generator Unit, u, for the calculations in the ranked set at rank, n, in Imbalance Settlement Period, γ;

(c) QBIASuγ is the Biased Quantity for Generator Unit, u, in Imbalance Settlement Period, γ.

(d) (n – 1) is for the previous item in the ranked set;


A.6.7.9 The Market Operator shall calculate the Biased Accepted Bid Quantity (QABBIASuoiγ) for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement Period, γ, as follows:

QABBIASuoiγ=QABBIAS uoiγn

where:

(a) QABBIASuoiγn is the Biased Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, for position in the rank set, n, in Imbalance Settlement Period, γ.

[A.6.7.10] The provisions of section A.6.7 do not apply to any Generator Unit which is registered as part of an Autoproducer Site..

A.6.7.10[A.6.7.11] The provisions of paragraphs A.6.7.1 to A.6.7.9 do not apply to any unit which is an Interconnector Error Unit.

A.6.7.11[A.6.7.12] The Market Operator shall:

[(a)] assign the Biased Accepted Offer Quantities and Biased Accepted Bid Quantities, QAOBIASuoiγ and QABBIASuoiγ, calculated in accordance with paragraphs A.6.7.2 to A.6.7.9 for an Interconnector Residual Capacity Unit, u, to the relevant Interconnector Error Unit, u; , and

(a)[(b)] set the values of the quantities referred to in paragraph (a) for the Interconnector Residual Capacity Unit to zero,

for the purposes of any processes using these quantities.

A.6.8 Calculation of Premium and Discount Component Payments

Explanatory Note


- In all the previous sections, and in a section to come, the quantities to be considered as part of the premium and discount cash flow calculation have been determined. This section applies the premium (if the bid offer price is greater than the imbalance settlement price) and the discount (if the bid offer price is less than the imbalance settlement price) to the correct volumes. Consider that the imbalance component already pays the imbalance settlement price, so this component only needs to pay

47

the difference between the bid offer price and imbalance settlement price.

- The premium is paid to accepted offer quantities which are:

o Delivered (therefore subtract undelivered);

o Not due to TOTSO (therefore subtract TOTSO);

o Not due to bias (therefore subtract BIAS); and

o Not paid a different price (therefore subtract OPO, offer price only).

- The discount is paid to accepted bid quantities which are:

o Delivered (therefore subtract undelivered);

o Not due to TOTSO (therefore subtract TOTSO);

o Not due to bias (therefore subtract BIAS);

o Firm (therefore subtract non-firm, NF); and

o Not paid a different price (therefore subtract BPO, bid price only, and CURL, curtailment).

- All of these quantities might cover the same volume, e.g. a TOTSO volume could also be undelivered. Therefore to ensure against double-counting the same volume, the largest of the values for the given BOA, o, and band, i, is taken: if there are volumes in the same band (output range) for the same BOA, they are the same volume. The largest value is found by taking the max of the positive quantity values for the premium, the min of the negative quantity values for the discount.

A.6.8.1 The Market Operator shall calculate Premium and Discount Component Payments for each Generator Unit, u, and each Imbalance Settlement Period, γ, as follows:

CPREMIUM uγ=∑o∑i

(Max (PBOuβoiγ−PIMBγ ,0 )× (QAOLFuoiγ−Max (QAOOPOLFuoiγ ,QAOBIASuoiγ ,QAOUNDELuoiγ ,QAOTOTSOLFuoiγ ) ))

CDISCOUNT uγ=∑o∑i

(Min (PBOuβoiγ−PIMBγ ,0 )× (QABLFuoiγ−Min (QABBPOLFuoiγ ,QABBIASuoiγ ,QABUNDELuoiγ ,QABNFLFuoiγ ,QABCURLLF uoiγ ,QABTOTSOLFuoiγ )))

where:


[(b)] PBOuβoiγ is the Bid Offer Price for each individual Accepted Bid Quantity and Accepted Offer Quantity for Generator Unit, u, time stamped, β, as the last one submitted by the relevant Participant beforefor Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ, determined in accordance with section A.6.3;

(b)[(c)] QAOLFuoiγ is the Loss-Adjusted Accepted Offer Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ, calculated in accordance with section Error:Reference source not found;

(c)[(d)] QABLFuoiγ is the Loss-Adjusted Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ, calculated in accordance with section Error:Reference source not found;

(d)[(e)] QAOTOTSOLFuoiγ is the Loss-Adjusted Trade Opposite TSO Accepted Offer Quantity for Generator Unit, u, for Bid Offer

48

Acceptance, o, for Band, i, in Imbalance Settlement Period, γ, calculated in accordance with section A.6.4;

(e)[(f)] QABTOTSOLFuoiγ is the Loss-Adjusted Trade Opposite TSO Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ, calculated in accordance with section A.6.4;

(f)[(g)] QABNFLFuoiγ is the Loss-Adjusted Non-Firm Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ, calculated in accordance with section A.6.5;

(g)[(h)] QAOUNDELuoiγ is the Undelivered Accepted Offer Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ, calculated in accordance with section A.6.6;

(h)[(i)] QABUNDELuoiγ is the Undelivered Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ, calculated in accordance with section A.6.6;

(i)[(j)] QAOBIASuoiγ is the Biased Accepted Offer Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ, calculated in accordance with section A.6.7;

(j)[(k)] QABBIASuoiγ is the Biased Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ, calculated in accordance with section A.6.7;

(k)[(l)] QABCURLLFuoiγ is the Loss-Adjusted Curtailment Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ, calculated in accordance with section A.8.1;

(l)[(m)] QAOOPOLFuoiγ is the Loss-Adjusted Offer Price Only Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ, calculated in accordance with section A.7.1;

(m)[(n)] QABBPOLFuoiγ is the Loss-Adjusted Bid Price Only Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ, calculated in accordance with section A.7.1.

A.6.8.2 The provisions in paragraph A.6.8.1 do not apply to any unit which is:

(a) An Assetless Unit;

(b) A Trading Unit;

(c) An Autonomous Generator Unit.

A.7 ACCEPTED OFFERS BELOW PHYSICAL NOTIFICATION, AND ACCEPTED BIDS ABOVE PHYSICAL NOTIFICATION, QUANTITIES, PAYMENTS AND CHARGES

Explanatory notes

- Functionality for determining when the refined approach is to be used, of applying the bid or offer price only to a BOA where that volume is due to the TSO undoing an earlier BOA, i.e.: incs from a point below the PN, and decs from a point above the

49

PN.

- Calculating the volume to which the refined approach applies and removing this from the premium component for incs.

- Calculating the volume to which the refined approach applies and removing this from the discount component for decs.

- Applying the correct offer or bid price to the volume to which the refined approach applies for incs and decs respectively.

- The volume is removed from the premium/discount component by explicitly subtracting the volume and imbalance component by implicitly applying the negative of the imbalance settlement price to the volume to which the refined approach is applied to counter the positive imbalance settlement price on that volume in the imbalance component, and then the relevant bid or offer price is applied to the volume.

A.7.1 Calculation of Accepted Offers Below Physical Notification and Accepted Bids Above Physical Notification Quantities

Explanatory Note


- This is the same as the formulation of qBOA calculation but tweaked to isolate only those volumes which are being sought for this different treatment.

- In this case, the volumes sought are those inc offers accepted which were from a point below the FPN, and those dec offers accepted which were from a point above the FPN. This amounts to an undo, e.g. if an inc offer was accepted through one dispatch instruction (from calculate qBOA from FPN to qD1), but then another dispatch instruction was issued to have the unit output lower than was intended by the original inc, a dec bid would be calculated from a start point above the FPN (from qD1 to qD2), this would be an undo and the detailed design said this should only be remunerated at the bid-offer price, not the better of the bid-offer price and imbalance settlement price.

- How these volumes are isolated are through the second line of the conditions for incs and decs where:

o the dispatch quantity for the current order is stopped at the FPN quantity for incs when the dispatch quantity is rising from a lower level up to the FPN quantity (by taking the minimum); and

o the dispatch quantity for the current order is stopped at the FPN quantity for decs when the dispatch quantity is falling from a higher level down to the FPN quantity.

- All the other lines are as per qBOA calculation.

A.7.1.1 The Market Operator shall calculate two values for the Price Only Accepted Bid Offer Quantity (qBOAPOuoiγ(t)) as a function of time, for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement Period, γ, calculating separately one value for all Incs resulting from the Bid Offer Acceptance and one value for all Decs resulting from the Bid Offer Acceptance as follows:

(a) For i > 0:

qBOAPOuoiγ ( t )=Max {Min {qDA uoγ ( t ) , qBOURuiγ ( t ) } , qBOURu (i−1) γ (t ) }−Max {Min {qDAu (o−1) γ (t ) , qBOURuiγ ( t ) }, qBOURu (i−1) γ (t ) }

50

(b) For i < 0:

qBOAPOuoiγ ( t )=Min {Max {qDA uoγ ( t ) , qBOLRuiγ (t ) } , qBOLRu (i+1 ) γ (t ) }−Min {Max {qDAu (o−1 ) γ (t ) , qBOLRuiγ (t ) }, qBOLRu (i+1)γ (t ) }

A.7.1.2 When calculating the value for the Price Only Accepted Bid Offer Quantity (qBOAPOuoiγ(t)) for the Incs resulting from the Bid Offer Acceptance, the Market Operator shall calculate the relevant variables as follows:

qDAuoγ ( t )=qDAPOuoγ ( t)

qDAPOuoγ ( t )=Min (Max (qDuoγ ( t ) , qDAu ( o−1) γ ( t ) ) , qFPN uγ (t ) )

qDAu (o−1) γ (t )=qDu (o−1 ) γ (t )

qDu (o=0) γ ( t )=qFPNuγ (t )

qBOURu ( i=0) γ ( t )=0

qBOLRu (i=0) γ (t )=0

A.7.1.3 When calculating the value for the Price Only Accepted Bid Offer Quantity (qBOAPOuoiγ(t)) for the Decs resulting from the Bid Offer Acceptance, the Market Operator shall calculate the relevant variables as follows:

qDAuoγ ( t )=qDAPOuoγ ( t)

qDAPOuoγ ( t )=Max (Min (qDuoγ ( t ) , qDAu ( o−1) γ ( t ) ) , qFPN uγ (t ) )

qDAu (o−1) γ ( t )=qDu (o−1 ) γ ( t )

qDu (o=0) γ ( t )=Min (qFPN uγ (t ) ,qAVAILOuγ (t ) )

qBOURu ( i=0) γ ( t )=0

qBOLRu (i=0) γ (t )=0

A.7.1.4 For the purposes of paragraphs A.7.1.1 to A.7.1.3:



(c) qDAPOuoγ(t) is the Price Only Adjusted Dispatch Quantity as a function of time for Generator Unit, u, for Bid Offer Acceptance, o, in Imbalance Settlement Period, γ;

51

(d) qBOURuiγ(t) is the Bid Offer Upper Range Quantity as a function of time for Generator Unit, u, for Band, i, in Imbalance Settlement Period, γ;

(e) qBOLRuiγ(t) is the Bid Offer Lower Range Quantity as a function of time for Generator Unit, u, for Band, i, in Imbalance Settlement Period, γ;

(f) qFPNuγ(t) is the Final Physical Notification Quantity as a function of time for Generator Unit, u, in Imbalance Settlement Period, γ;

(g) qAVAILOuγ(t) is the Outturn Availability Quantity as a function of time for Generator Unit, u, in Imbalance Settlement Period, γ;

(h) (o – 1) is for the previous Bid Offer Acceptance;

(i) (i – 1) is for the previous Band when considering Bands in the positive direction (i > 0);

(j) (i + 1) is for the previous Band when considering Bands in the negative direction (i < 0);

(k) (o = 0) or (i = 0) is for the 0th value for the relevant aspect (i.e. the implicit default value before an explicit Bid Offer Acceptance, o; the value for Band, i, where i = 0).

A.7.1.5 The Market Operator shall calculate the Offer Price Only Accepted Offer Quantity (qAOOPOuoiγ(t)) as a function of time, and the Bid Price Only Accepted Bid Quantity (qABBPOuoiγ(t)) as a function of time, for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement Period, γ, as follows:

qAOOPOuoiγ (t)=Max (qBOAPOuoiγ (t ) for Incs ,0)

qABBPOuoiγ (t)=Min (qBOAPOuoiγ ( t ) for Decs ,0)

where:

(a) qBOAPOuoiγ(t) is the Price Only Accepted Bid Offer Quantity as a function of time for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ.

A.7.1.6 The Market Operator shall calculate the Offer Price Only Accepted Offer Quantity (QAOOPOuoiγ) as an integrated period quantity, and the Bid Price Only Accepted Bid Quantity (QABBPOuoiγ) for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ, by integrating the associated function of time Offer Price Only Accepted Offer Quantity (qAOOPOuoiγ(t)) and Bid Price Only Accepted Bid Quantity qABBPOuoiγ(t)) over the Imbalance Settlement Period, γ.

A.7.2 Calculation of Accepted Offers Below Physical Notification and Accepted Bids Above Physical Notification Payments and Charges

Explanatory Note


- The bid-offer price should be applied to the undo volumes as determined in the previous section, which have been delivered;

- Since the imbalance component applies the imbalance settlement price to the volume

52

already, this is countered by applying the negative of the imbalance settlement price to the volume. This is why there is a “-PIMB” term, and this has the effect of “removing” the undo volume from the imbalance component.

- The Bid Offer price is then also applied to the volume. This means that, since the volume is implicitly removed from the imbalance component as explained by the previous bullet point, and is explicitly removed from the premium/discount component as explained in section A.6.8, there is no price applied to it in any other section, so the application of the bid offer price in this equation means it is only remunerated at the bid offer price.

- For decs, the same volume might be an undo quantity as calculated in this section, and a curtailment quantity. Therefore only the amount of the undo quantity which is not a curtailment quantity gets settled in this way. The amount which is a curtailment quantity gets settled in the next section.

A.7.2.1 The Market Operator shall calculate the Offer Price Only Accepted Offer Payment or Charge (CAOOPOuγ) and the Bid Price Only Accepted Bid Payment or Charge (CABBPOuγ) for each Generator Unit, u, in each Imbalance Settlement Period, γ, as follows:

CAOOPOuγ=∑o∑i

((PBOuβoiγ−PIMBγ )×Max (QAOOPOLFuoiγ−QAOUNDELuoiγ ,0 ))

CABBPOuγ=∑o∑i

( (PBOuβoiγ−PIMBγ )×Min (QABBPOLFuoiγ−Min (QABCURLLFuoiγ ,QABUNDELuoiγ ) ,0) )

where:


[(b)] PBOuβoiγ is the Bid Offer Price for each individual Accepted Bid Quantity and Accepted Offer Quantity for Generator Unit, u, time stamped, β, as the last one submitted by the relevant Participant beforefor Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ;

(b)[(c)] QAOOPOLFuoiγ is the Loss-Adjusted Offer Price Only Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ;

(c)[(d)] QABBPOLFuoiγ is the Loss-Adjusted Bid Price Only Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ;

(d)[(e)] QAOUNDELuoiγ is the Undelivered Accepted Offer Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ;

(e)[(f)] QABCURLLFuoiγ is the Loss-Adjusted Curtailment Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ;

(f)[(g)] QABUNDELuoiγ is the Undelivered Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ.

A.7.2.2 The provisions in section A.7 do not apply to any unit which is:


53

(b) A Trading Unit;

(c) An Interconnector Error Unit;

(d) An Interconnector Residual Capacity Unit;

(e)[(d)] An Autonomous Generator Unit.

A.8 CURTAILMENT QUANTITIES, PRICES, PAYMENTS AND CHARGES

Explanatory notes

- Functionality for determining the situations when the calculations for curtailed volumes are needed, depending on when a dispatch instruction is issued with a curtailment flag.

- Calculating the curtailed volume for a unit when the situation requires this calculation, and removing this from the discount component for decs.

- If the situation arises where the refined approach to decs coincides with the curtailment volume, remove the curtailed volume from the volume receiving the bid price under the refined approach.

- Applying the curtailment price to the curtailed dec volume.

A.8.1 Calculation of Curtailment Quantities

Explanatory Note


- This is the same as a qBOA calculation but isolating only those quantities which are due to curtailment.

- Curtailment is only ever a decremental quantity, therefore only inputs for decs apply.

- How this is done is in the second line, by having a dispatch curve to follow which is different to the previous dispatch curve only when the dispatch instruction to result in that BOA had a curtailment flag. Otherwise, the dispatch curve for this calculation will be the same as the previous dispatch curve, meaning when the inputs come to Parts (a) and (b), a value of zero should always result. A non-zero value should only result when the DI has a curtailment flag;

- All other lines are as per qBOA calculation.

A.8.1.1 The Market Operator shall calculate the Curtailment Accepted Bid Offer Quantity (qBOACURLuoiγ(t)) as a function of time for each Generator Unit, u, for all Decs resulting from each Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement Period, γ, as follows:

(a) For i > 0:

qBOACURLuoiγ (t )=Max {Min {qDAuoγ ( t ) , qBOURuiγ (t ) } , qBOURu (i−1 ) γ ( t ) }−Max {Min {qDA u (o−1) γ (t ) , qBOURuiγ ( t ) } , qBOURu (i−1 )γ ( t )}

(b) For i < 0:

qBOACURLuoiγ (t )=Min {Max {qDAuoγ ( t ) , qBOLRuiγ ( t ) } , qBOLRu (i+1 ) γ ( t ) }−Min {Max {qDAu (o−1 ) γ (t ) , qBOLRuiγ (t ) }, qBOLRu (i+1)γ ( t ) }

54

A.8.1.2 When calculating the value for the qBOACURLuoiγ(t) for the Decs resulting from the Bid Offer Acceptance, the Market Operator shall calculate the relevant variables as follows:

qDAuoγ (t )=qDACURLuoγ (t)

If DI for ohascurtailment flag , thenqDACURLuoγ (t )=Min (qDuoγ ( t ) , qDAu (o−1) γ ( t ) )elseqDACURLuoγ (t )=qDAu (o−1) γ ( t )

qDAu (o−1) γ ( t )=qDu(o−1)γ (t )

qDu (o=0) γ ( t )=Min (qFPN uγ (t ) ,qAVAILOuγ (t ) )

qBOURu ( i=0) γ ( t )=0


where:



(c) QDACURLuoγ(t) is the Curtailment Adjusted Dispatch Quantity as a function of time for Generator Unit, u, for Bid Offer Acceptance, o, in Imbalance Settlement Period, γ;

(d) qBOURuiγ(t) is the Bid Offer Upper Range Quantity as a function of time for Generator Unit, u, for Band, i, in Imbalance Settlement Period, γ;

(e) qBOLRuiγ(t) is the Bid Offer Lower Range Quantity as a function of time for Generator Unit, u, for Band, i, in Imbalance Settlement Period, γ;

(f) qFPNuγ(t) is the Final Physical Notification Quantity as a function of time for Generator Unit, u, in Imbalance Settlement Period, γ;

(g) qAVAILOuγ(t) is the Outturn Availability Quantity as a function of time for Generator Unit, u, in Imbalance Settlement Period, γ;

(h) (o – 1) is for the previous Bid Offer Acceptance.

(i) (i – 1) is for the previous Band when considering Bands in the positive direction (i > 0);

(j) (i + 1) is for the previous Band when considering Bands in the negative direction (i < 0);

55

(k) (o = 0) or (i = 0) is for the 0th value for the relevant aspect (i.e. the implicit default value before an explicit Bid Offer Acceptance, o; the value for Band, i, where i = 0).

A.8.1.3 The Market Operator shall calculate the Curtailment Accepted Bid Quantity (qABCURLuoiγ(t)) as a function of time, for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement Period, γ, as follows:

qABCURLuoiγ(t )=Min (qBOACURLuoiγ (t ) for Decs ,0 )

where:

(a) qBOACURLuoiγ(t) is the Curtailment Accepted Bid Offer Quantity as a function of time for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ.

A.8.1.4 The Market Operator shall calculate the Curtailment Accepted Bid Quantity (QABCURLuoiγ) as an integrated quantity for the Imbalance Settlement Period γ, by integrating the associated function of time version of the Curtailment Accepted Bid Quantity (qABCURLuoiγ(t)) with respect to time across the Imbalance Settlement Period, γ.

A.8.2 Calculation of Curtailment Prices[A.8.2.1] The Market Operator shall calculate the Curtailment Price (PCURLuγ) for

Generator Unit, u, in Imbalance Settlement Period, γ, in accordance with the curtailment price process in section [on ex-ante market referencecurtailment price calculations].

A.8.3 Calculation of Curtailment Payments and Charges

Explanatory Note


- Implicitly remove the curtailed quantity from the imbalance component (by applying “-PIMB” to it), and apply the curtailment price to the delivered, unbiased quantities (PCURL). Since the quantity has been removed from the premium/discount component, this is now the only price applied to this volume.

- The undelivered quantity is removed to only remunerate delivered quantities, and the biased quantity is removed to only remunerate those curtailment decs which mean the volume of output of the unit is less than the ex-ante market position of the unit: the biased quantities are decs above the ex-ante market position.

A.8.3.1 The Market Operator shall calculate the Curtailment Charge (CCURLuγ) for each Generator Unit, u, in each Imbalance Settlement Period, γ, as follows:

CCURLuγ=∑o∑i

( (PCURLγ−PIMBγ )× (QABCURLLFuoiγ−Min (QABBIASuoiγ ,QABUNDELuoiγ )) )

where:


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(b) PCURLuγ is the Curtailment Price for Generator Unit, u, in Imbalance Settlement Period, γ;

(c) QABCURLLFuoiγ is the Loss-Adjusted Curtailment Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ;

(d) QABUNDELuoiγ is the Undelivered Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ;

(e) QABBIASuoiγ is the Biased Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ.



(b) A Trading Unit;



(e)[(d)] An Autonomous Generator Unit.

A.9 UNINSTRUCTED IMBALANCE QUANTITIES AND CHARGES

Explanatory notes

- Calculate the values for the tolerances allowed for uninstructed imbalances (over generation and under generation).

- Calculate the uninstructed imbalance volume on a unit for a period (different than the imbalance component which includes instructed imbalances, this is the difference between what the unit was instructed to do, and what they delivered), and the volume thereof which is outside of the allowed tolerance.

- Determine, from the orders accepted and the uninstructed imbalance volume on the unit, the volume of the orders, in whole or a fraction, which were not delivered and outside of the allowed tolerance (i.e. for over-delivery, decs deemed not to have been delivered, for under-delivery, incs deemed not to have been delivered).

- Calculate the additional charge to be applied to the uninstructed imbalance volume outside of tolerance at the imbalance Settlement price (imbalance component of the uninstructed imbalance charge).

- Calculate the additional charge to be applied to the premium or discount for the undelivered volumes which were deemed to be outside the allowed tolerance.

A.9.1 Setting of Uninstructed Imbalance ParametersA.9.1.1 If requested by the Regulatory Authorities, the System Operators shall report

to the Regulatory Authorities [at least four months before the start of the Year], proposing values for the following parameters to be used in the calculation of Uninstructed Imbalances for that Year:

(a) The Engineering Tolerance (TOLENG) (where 0 TOLENG 1);

(b) The MW Tolerance (TOLMWt) (where 0 TOLMWt) for each Trading Day, t;

(c) The System per Unit Regulation Factor (FUREG);

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(d) The Discount for Over Generation Factor (FDOGuγ) for each Generator Unit, u, in each Imbalance Settlement Period, γ, such that 0 FDOGuγ 1; and

(e) The Premium for Under Generation Factor (FPUGuγ) for each Generator Unit, u, in each Imbalance Settlement Period, γ, such that 0 FPUGuγ 1.

A.9.1.2 The System Operators’ report must set out any relevant research or analysis carried out by the System Operators and any justification for the specific values proposed. The report may, and shall if so requested by the Regulatory Authorities, include alternative values from those proposed and must set out the arguments for and against such alternatives.

A.9.1.3 The System Operators shall[, in accordance with Appendix K “Market Data Transactions”,] provide to the Market Operator at least [two months] prior to the start of each Year or within [5 Working Days] of approval by the Regulatory Authorities, whichever is the later, the Uninstructed Imbalance Parameters Data Transaction, which comprises a complete set of Uninstructed Imbalance Parameters that have been approved by the Regulatory Authorities for that Year.

A.9.1.4 The Market Operator shall publish the approved value(s) for each Uninstructed Imbalance Parameter within [5 Working Days] of receipt of the Regulatory Authorities' determination or [two months] before the start of the Year to which they shall apply whichever is the later.

A.9.2 Calculation of Uninstructed Imbalance Tolerance QuantitiesA.9.2.1 For each Trading Day, each System Operator shall submit to the Market

Operator the System Characteristics Data, consisting of values of Nominal System Frequency (FRQNORγ) and Average System Frequency (FRQAVGγ) for each Imbalance Settlement Period, γ, in that Trading Day, Market Operator[, in accordance with Appendix K “Market Data Transactions”].

A.9.2.2 The Market Operator shall calculate the Tolerance Bands for over generation and under generation for each Generator Unit for each Trading Period with reference to system frequency and the frequency characteristics of the Generator Unit in accordance with paragraphs A.9.2.3 and A.9.2.4.

A.9.2.3 The Market Operator shall calculate the Engineering Limit Quantity (qLIMENGuγ) for each Generator Unit, u, in each Imbalance Settlement Period, γ, as follows:

qLIMENGuγ=Max(|QDuγDISP|×TOLENG ,TOLMW t)where:

(a) QDuγ is the Dispatch Quantity for Generator Unit, u, in Imbalance Settlement Period, γ;

(b) TOLENG is the Engineering Tolerance;

(c) DISP is the Imbalance Settlement Period Duration; and

(d) TOLMWt is the MW Tolerance for the relevant Imbalance Settlement Period, γ, within Trading Day, t.

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A.9.2.4 The Market Operator shall calculate the Tolerance for Over Generation (TOLOGuγ) and Tolerance for Under Generation (TOLUGuγ) as positive values, expressed in MW, for each Generator Unit, u, in each Imbalance Settlement Period, γ, as follows:

If FRQAVGγ≤FRQNORγ , then

TOLOGuγ=( (FRQNORγ−FRQAVGγ )×qCRuFUREG× FRQNORγ )+qLIMENGuγ

TOLUGuγ=qLIMENGuγelseTOLOGuγ=qLIMENGuγ

TOLUGuγ=( (FRQAVGγ−FRQNOR γ )×qCRuFUREG× FRQNORγ )+qLIMENGuγ

where:

(a) FRQAVGγ is the Average System Frequency in Imbalance Settlement Period, γ;

(b) FRQNORγ is the Nominal System Frequency in Imbalance Settlement Period, γ;

(c) qCRu is the Registered Capacity of Generator Unit, u;

(d) FUREG is the System per Unit Regulation parameter; and

(e) qLIMENGuγ is the Engineering Limit Quantity for Generator Unit, u, in Imbalance Settlement Period, γ.

A.9.2.5 The provisions of section A.9.2 do not apply to any unit which isan Interconnector Error Unit.

A.9.3 Calculation of Uninstructed Imbalance QuantitiesA.9.3.1 The Market Operator shall calculate the Outside Tolerance Undelivered

Quantity (QUNDELOTOLuγ) for each Generator Unit, u, in Imbalance Settlement Period, γ, as follows:

If (QMLFuγ−QDLFuγ )<0 , thenQUNDELOTOLuγ=Min ( (QMLFuγ−QDLFuγ )+TOLUGLFuγ ,0 )

If (QMLFuγ−QDLFuγ )>0 , thenQUNDELOTOLuγ=Max ((QMLF uγ−QDLF uγ )−TOLOGLFuγ ,0 )

where:

(a) QMLFuγ is the Loss-Adjusted Metered Quantity for Generator Unit, u, in Imbalance Settlement Period, γ;

(b) QDLFuγ is the Loss-Adjusted Dispatch Quantity for Generator unit, u, in Imbalance Settlement Period, γ;

(c) TOLUGLFuγ is the Loss-Adjusted Tolerance for Under Generation for Generator Unit, u, in Imbalance Settlement Period, γ; and

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(d) TOLOGLFuγ is the Loss-Adjusted Tolerance for Over Generation for Generator Unit, u, in Imbalance Settlement Period, γ.

A.9.3.2 Where the Outside Tolerance Undelivered Quantity has a positive value, the Market Operator shall determine which of the Undelivered Accepted Bid Quantities were outside of tolerance, in whole or in part, for each Generator Unit, u, in Imbalance Settlement Period, γ, in accordance with paragraphs A.9.3.3 to A.9.3.6.

A.9.3.3 The Market Operator shall derive a ranked set of all Undelivered Accepted Bid Quantities for Generator Unit, u, in Imbalance Settlement Period, γ, in order of increasing price. The Undelivered Accepted Bid Quantity with the lowest price will be allocated a rank number n = 1, the next lowest priced Undelivered Accepted Bid Quantity a rank number n = 2 and so on until all Undelivered Accepted Bid Quantities have been allocated a rank number. Where two or more Undelivered Accepted Bid Quantities have equal prices, they shall be ranked using a systematic process of random selection which may include making small alterations to the submitted prices. Any such amended prices will only be used for this purpose in the ranking process.

Explanatory Note

The intention of the equations in sections A.9.3.4 to A.9.3.15 below is as follows:

- This is the same as the function for determining which quantities are undelivered used in Section A.6.6, but with different inputs. Now we only want to see which of the undelivered quantities were outside of tolerance

A.9.3.4 The Market Operator shall calculate the Outside Tolerance Undelivered Accepted Bid Quantity (QABUNDELOTOLuoiγn) for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in ascending order of each position, n, in the ranked set, in Imbalance Settlement Period, γ, as follows:

QABUNDELOTOLuoiγn=Min (Max (QABUNDELuoiγn ,−QUNDELOTOLRuγ (n−1 ) ) ,0 )

QUNDELOTOLRuγn=QUNDELOTOLRuγ (n−1 )+QABUNDELOTOLuoiγn

QUNDELOTOLRuγ (n=0 )=QUNDELOTOLuγ


where:

(a) QABUNDELuoiγn is the Undelivered Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in the ranked set at rank, n, in Imbalance Settlement Period, γ;

(b) QUNDELOTOLRuγn is the Remaining Outside Tolerance Undelivered Quantity for Generator Unit, u, for the calculations in the ranked set at rank, n, in Imbalance Settlement Period, γ;

(c) QUNDELOTOLuγ is the Outside Tolerance Undelivered Quantity for Generator Unit, u, in Imbalance Settlement Period, γ;


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A.9.3.5 The Market Operator shall calculate the Outside Tolerance Undelivered Accepted Bid Quantity (QABUNDELOTOLuoiγ) for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement Period, γ, as follows:

QABUNDELOTOLuoiγ=QABUNDELOTOLuoiγn

where:

(a) QABUNDELOTOLuoiγn is the Outside Tolerance Undelivered Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, for position in the rank set, n, in Imbalance Settlement Period, γ.

A.9.3.6 The Market Operator shall determine the Outside Tolerance Undelivered Accepted Offer Quantity (QAOUNDELOTOLuoiγ) for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement Period, γ, as follows:

QAOUNDELOTOLuoiγ=0

A.9.3.7 Where the Outside Tolerance Undelivered Quantity has a negative value, the Market Operator shall determine which of the Undelivered Accepted Offer Quantities were outside of tolerance, in whole or in part, for each Generator Unit, u, in Imbalance Settlement Period, γ, in accordance with paragraphs A.9.3.8 to A.9.3.11.

A.9.3.8 The Market Operator shall derive a ranked set of all Undelivered Accepted Offer Quantities for Generator Unit, u, in Imbalance Settlement Period, γ, in order of decreasing price. The Undelivered Accepted Offer Quantity with the highest price will be allocated a rank number n = 1, the next highest priced Undelivered Accepted Offer Quantity a rank number n = 2 and so on until all Undelivered Accepted Offer Quantities have been allocated a rank number. Where two or more Undelivered Accepted Offer Quantities have equal prices, they shall be ranked using a systematic process of random selection which may include making small alterations to the submitted prices. Any such amended prices will only be used for this purpose in the ranking process.

A.9.3.9 The Market Operator shall calculate the Outside Tolerance Undelivered Accepted Offer Quantity (QAOUNDELOTOLuoiγn) for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in ascending order of each position, n, in the ranked set, in Imbalance Settlement Period, γ, as follows:

QAOUNDELOTOLuoiγn=Max (Min (QAOUNDELuoiγn ,−QUNDELOTOLRuγ (n−1) ) ,0 )

QUNDELOTOLRuγn=QUNDELOTOLRuγ (n−1 )+QAOUNDELOTOLuoiγn

QUNDELOTOLRuγ (n=0 )=QUNDELOTOLuγ

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where:

(a) QAOUNDELuoiγn is the Undelivered Accepted Offer Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in the ranked set at rank, n, in Imbalance Settlement Period, γ;

(b) QUNDELOTOLRuγn is the Remaining Outside Tolerance Undelivered Quantity for Generator Unit, u, for the calculations in the ranked set at rank, n, in Imbalance Settlement Period, γ;

(c) QUNDELOTOLuγ is the Outside Tolerance Undelivered Quantity for Generator Unit, u, in Imbalance Settlement Period, γ;



A.9.3.10 The Market Operator shall calculate the Outside Tolerance Undelivered Accepted Offer Quantity (QAOUNDELOTOLuoiγ) for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement Period, γ, as follows:

QAOUNDELOTOLuoiγ=QAOUNDELOTOLuoiγn

where:

(a) QAOUNDELOTOLuoiγn is the Outside Tolerance Undelivered Accepted Offer Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, for position in the rank set, n, in Imbalance Settlement Period, γ.

A.9.3.11 The Market Operator shall determine Outside Tolerance Undelivered Accepted Bid Quantity (QABUNDELOTOLuoiγn) for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement Period, γ, as follows:

QABUNDELOTOLuoiγ=0

A.9.3.12 Where the Outside Tolerance Undelivered Quantity has a zero value, the Market Operator shall determine the Outside Tolerance Undelivered Accepted Offer Quantity (QAOUNDELOTOLuoiγ) and Outside Tolerance Undelivered Accepted Bid Quantity (QABUNDELOTOLuoiγn) for each Generator Unit, u, for each Bid Offer Acceptance, o, for each Band, i, in Imbalance Settlement Period, γ, as follows:

QAOUNDELOTOLuoiγ=0

QABUNDELOTOLuoiγ=0

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[A.9.3.13] The price for each Outside Tolerance Undelivered Accepted Offer Quantity and Outside Tolerance Undelivered Accepted Bid Quantity (PBOuβoiγ) shall be the same as the price for the individual Accepted Bid Quantity and Accepted Offer Quantity to which they are related through belonging to the same Generator Unit, u, and Bid Offer Acceptance, o, and Band, i, and Imbalance Settlement Period, γ.

A.9.3.13[A.9.3.14] The provisions of paragraphs A.9.3.1 to A.9.3.13 do not apply to any unit which is an Interconnector Error Unit.

A.9.3.14[A.9.3.15] The Market Operator shall assign the Outside Tolerance Undelivered Accepted Offer Quantities and Outside Tolerance Undelivered Accepted Bid Quantities, QAOUNDELOTOLuoiγ and QABUNDELOTOLuoiγ, calculated in accordance with paragraphs A.9.3.1 to A.9.3.13 for an Interconnector Residual Capacity Unit, u, to the Interconnector Error Unit, u, relevant to the same Interconnector, l, as the Interconnector Residual Capacity Unit, and shall set the values of these quantities for the Interconnector Residual Capacity Unit to zero, for the purposes of all following processes using these quantities.

A.9.4 Calculation of Uninstructed Imbalance Charges

Explanatory Note


- This is slightly different to the SEM. In the SEM, uninstructed imbalances outside of tolerance are paid an adjusted price. In the I-SEM, all uninstructed imbalances are paid the imbalance Settlement price through the imbalance component, and a premium/discount if applicable. This section calculates the “adjustment” to the price, in the form of an additional charge.

- If the total undelivered outside of tolerance quantity is negative (undergeneration), the PUG is applied. It is firstly applied to the imbalance Settlement price which was used to settle all the volume, and then applied to the discount which was used to settle the accepted bid quantities.

- If the total undelivered outside of tolerance quantity is positive (overgeneration), similarly a DOG is applied.

A.9.4.1 Subject to paragraph A.9.4.2, the Market Operator shall calculate the Uninstructed Imbalance Charge (CUNIMBuγ) for each Generator Unit, u, in each Imbalance Settlement Period, γ, as follows:

CUNIMBuγ=Min (QUNDELOTOLuγ ,0 )× ( (F PUGuγ×PIMBγ ))+Max (QUNDELOTOLuγ ,0 )× (−(F DOGuγ×PIMBγ ) )+∑o∑i

−FDOGuγ× (Min (PBOuβoiγ−PIMBγ ,0 )× (QABUNDELOTOLuoiγ ))+∑o∑i

−FPUGuγ× (Max (PBOuβoiγ−PIMBγ ,0 )× (QAOUNDELOTOLuoiγ ))

where:

(a) QUNDELOTOLuγ is the Outside Tolerance Undelivered Quantity for Generator Unit, u, in Imbalance Settlement Period, γ.

(b) QAOUNDELOTOLuoiγn is the Outside Tolerance Undelivered Accepted Offer Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ.

(c) QABUNDELOTOLuoiγn is the Outside Tolerance Undelivered Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ.

(d) PIMBγ is the Imbalance Settlement Price in Imbalance Settlement Period, γ[, as calculated in section on Imbalance Pricing];

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[(e)] PBOuβoiγ is the Bid Offer Price for each individual Outside Tolerance Undelivered Accepted Bid Quantity and Outside Tolerance Accepted Offer Quantity for Generator Unit, u, time stamped, β, as the last one submitted by the relevant Participant beforefor Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ;

(e)[(f)] FPUGuγ is the Premium for Under Generation Factor for Generator Unit, u, in Imbalance Settlement Period, γ.

(f)[(g)] FDOGuγ is the Discount for Over Generation Factor for Generator Unit, u, in Imbalance Settlement Period, γ.

A.9.4.2 When a Pumped Storage Unit, u, is in Pumping Mode for an Imbalance Settlement Period, γ, or any part thereof, the Market Operator shall calculate the Imbalance Component Payment or Charge (CUNIMBuγ) for that Pumped Storage Unit, u, in each Imbalance Settlement Period, γ, for which it is in Pumping Mode, as having a value of zero.

A.9.4.3 The provisions of section A.9 do not apply to any unit which is:


(b) A Trading Unit;

(c) An Autonomous Generator Unit;


[(e)] An Autonomous Generator Unit .

A.10 INFORMATION IMBALANCE QUANTITIES AND CHARGES

Explanatory notes

- Calculate the information imbalance volume for a given period by calculating volumes, for all times where a PN submission relevant to that period can be made, of the differences between the submitted PN values for that period and the FPN submission for that period, and applying a weighting factor to each of those volumes to determine if that volume (or how much of that volume) makes up the total information imbalance volume.

- Determine the information imbalance charge to be applied in a particular period through the application of the information imbalance price to the calculated quantity.

A.10.1 Setting of Information Imbalance ParametersA.10.1.1 If requested by the Regulatory Authorities, the [Market Operator] shall report

to the Regulatory Authorities at least [4 months] before the start of the Year, proposing values for the following parameters to be used in the calculation of Information Imbalance Charges for that Year:

(a) The Information Imbalance Quantity Weighting Factor (WFQIIuβγ) for each Generator Unit, u, for each PN Submission Period, β, in respect of Imbalance Settlement Period, γ, for Year, y;

(b) The Information Imbalance Tolerance (TOLIIuβγ) for each Generator Unit, u, for each PN Submission Period, β, in respect of Imbalance Settlement Period, γ, for Year, y; and

(c) The Information Imbalance Price (PIIuγ) for each Generator Unit, u, in each Imbalance Settlement Period, γ.

A.10.1.2 The [Market Operator's] report must set out any relevant research or analysis carried out by the Market Operator and the justification or sources for the

64

specific values proposed. The report may, and shall if so requested by the Regulatory Authorities, include alternative values from those proposed and must set out the arguments for and against such alternatives.

A.10.1.3 The [Market Operator] shall publish the approved value(s) for each such parameter within [5 Working Days] of receipt of the Regulatory Authorities' determination or [two months] before the start of the year to which they shall apply, whichever is the later.

A.10.2 Calculation of Information Imbalance Quantities

Explanatory Note


- Determine the information imbalance quantity, which is the difference between the PN for period gamma at a certain submission time beta, and the FPN for gamma after all submission times for gamma have been finished. If this quantity is outside of a tolerance, it is considered. A weighting factor is then applied to only consider the quantities outside of tolerance arising in submission times we care about, e.g. we might not care if QPN is very different to QFPN at the start of the trading day, but if QPN is very different to QFPN 2 hours before real-time it could be deemed important].

A.10.2.1 The Market Operator shall calculate the Information Imbalance Quantity (QIIuγ) for each Generator Unit, u, in each Imbalance Settlement Period, γ, as follows:

QII uγ= ∑βrelevant ¿

γ ¿Max (|QPNuβγ−QFPN uγ|−TOLIIuβγ ,0 )×WFQII uβγ

where:

(a) QPNuβγ is the last valid Physical Notification Quantity for Generator Unit, u, in PN Submission Period, β, in respect of Imbalance Settlement Period, γ.

(b) ∑βrelevant ¿

γ ¿ is the sum, for each PN Submission Period β, in respect of

Imbalance Settlement Period γ.

(c) QFPNuγ is the Final Physical Notification Quantity for Generator Unit, u, in Imbalance Settlement Period, γ;

(d) WFQIIuβγ is the Information Imbalance Quantity Weighting Factor for Generator Unit, u, for PN Submission Period , β, in respect of Imbalance Settlement Period, γ; and

(e) TOLIIuβγ is the Information Imbalance Tolerance for Generator Unit, u, for PN Submission Period, β, in respect of Imbalance Settlement Period, γ.

A.10.3 Calculation of Information Imbalance ChargesA.10.3.1 The Market Operator shall calculate the Information Imbalance Charge (CIIuγ)

for each Generator Unit, u, in each Imbalance Settlement Period, γ, as follows:

CII uγ=PII uγ×QIILFuγ

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where:

(a) QIILFuγ is the Loss-Adjusted Information Imbalance Quantity for Generator Unit, u, in Imbalance Settlement Period, γ;

(b) PIIuγ is the Information Imbalance Price for Generator Unit, u, in Imbalance Settlement Period, γ.



(b) A Trading Unit;



(e) A unit which has Priority Dispatch, which is non-dispatchable;

(f) An Autonomous Generator Unit.

A.11 FIXED COST PAYMENTS AND CHARGES

Explanatory notes:

- Determine when a balancing market action results in the need to recover explicit start costs and no-load costs from three-part order formats as part of imbalance settlement.

- If three-part order formats required to be used, ensure that the following requirements are implemented in the functionality:

o Non-energy actions to have their fixed costs remunerated through side-payments;

o Energy actions can have their fixed costs reflected in, and remunerated through, the imbalance settlement price;

o Ensuring that generators do not over-recover start costs over a contiguous period;

o Functionality for Substitutive PNs, where the IDM price achieved replaces the price of the relevant balancing market order in full.

- Where explicit fixed costs need to be paid to a generator unit, do this through a make-whole payment where the running costs for a unit due to balancing market actions over a contiguous operating period and the revenue earned in the balancing market by that unit over the period are compared, with any costs not recovered being remunerated through an additional side-payment.

- Adjustments to the approach for the make-whole payment were made to capture the following case:

o When a unit has been started, shut-down, and started again all within a length of time with non-zero PN submitted, the previous approach would not have recognised this as an additional start-up cost. This approach was changed by ensuring that a start cost is recognised for every period of physical running which has no PN associated, and every new start after a shutdown within a length of time which has a PN associated.

- Additional functionality has been added to this to account for situations where fixed costs are recovered through a participant’s Complex COD rather than through their Simple Dec price. This is to fully enact the Building Blocks decision, which states:

o A unit that obtains an ex-ante market position or that is dispatched up will receive at least its offer price; and

o A unit that is constrained down from its ex-ante market position (and which has firm access) will retain its inframarginal rent.

- The second bullet point from the decision means that a unit would pay back their

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avoided fixed costs where applicable when constrained down, as avoided costs taken away from market revenue would leave inframarginal rent. A participant who has avoided a start/no-load can pay this back through their Dec price if the Simple Data applies, but there has not yet been provisions added for the functionality of paying avoided fixed costs when Complex COD applies. Changes to the following section reflect this additional required functionality:

o Start costs are considered recoverable if there is no dispatch over the Period of Market Operation (pure decommitment), and Complex COD applies;

o Start costs are also considered recoverable if the start of the Period of Market Operation, and the end of the previous Period of Market Operation, are in the same Period of Physical Operation. This captures situations where the TSO keeps a unit on when the unit was intending through its market position to shut down and start up again, i.e. the unit pays back the avoided start cost from the TSO keeping it on (again, if Complex COD applies);

o No-Load costs are considered recoverable if there is no dispatch quantity in an Imbalance Settlement Period within the Period of Market Operation (i.e. there is a FPN, but no dispatch), and Complex COD applies.

A.11.1 Determination of Periods of Physical Operation and Market OperationA.11.1.1 The Market Operator shall determine the start and end of each Period of

Physical Operation for each Generator Unit, u, in each Billing Period, b, as follows:

(a) A Period of Physical Operation will start at:

(i) The time where the value for the final Dispatch Quantity (qDuoγ(t)) of the Generator Unit, u, rises from zero; or

(ii) The start of a Billing Period, if the value for the final Dispatch Quantity (qDuoγ(t)) of the Generator Unit, u, was a positive number at the end of the immediately preceding Billing Period;

(b) A Period of Physical Operation will end at the earlier of:

(i) The time where the value for the final Dispatch Quantity (qDuoγ(t)) of the Generator Unit, u, becomes zero after previously being a positive number greater than zero; and

(ii) The end of a Billing Period.

A.11.1.2 The Market Operator shall determine the start and end of each Period of Market Operation for each Generator Unit, u, in each Billing Period, b, as follows:

(a) A Period of Market Operation will start at:

(i) The time where the value for the Final Physical Notification Quantity (qFPNuγ(t)) of the Generator Unit, u, rises from zero; or

(ii) The start of a Billing Period, if the value for the Final Physical Notification Quantity (qFPNuγ(t)) of the Generator Unit, u, was a positive number at the end of the immediately preceding Billing Period;

(b) A Period of Market Operation will end at the earlier of:

(i) The time where the value for the Final Physical Notification (qFPNuγ(t)) of the Generator Unit, u, becomes zero after previously being a positive number greater than zero; and

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(ii) The end of a Billing Period.

A.11.2 Determination of No-Load Costs and Start-Up Costs Payable and Recoverable

A.11.2.1 In each of the following circumstances the Start-Up Costs (CSUuγ) payable for each Generator Unit, u, in each Imbalance Settlement Period, γ, shall have a value of zero for each Imbalance Settlement Period, γ, falling wholly within the Period of Physical Operation, or in which the Period of Physical Operation starts or ends, as follows:

(a) When all Accepted Offer Quantities and Accepted Bid Quantities within the Period of Physical Operation are priced on the basis of the Simple Bid Offer Format Data as determined in section A.3.2;

(b) When the Metered Quantity (QMuγ) for the Generator Unit, u, has a value of zero for all Imbalance Settlement Periods, γ, falling wholly within the Period of Physical Operation, or in which the Period of Physical Operation starts or ends.

A.11.2.2 In all circumstances not listed in paragraphs A.11.2.1, for any Bid Offer Acceptance, o, within the Period of Physical Operation which is associated with a Synchronise Dispatch Instruction and for which Complex Bid Offer Format data is to be used in accordance with section A.3.2:

(a) CSUuγ for the first Imbalance Settlement Period, γ, within the Period of Physical Operation shall have a value equal to the value of the [Submitted Start Cost] relating to the Warmth State at the time of the start time of the Period of Physical Operation submitted for the Generator Unit as part of the applicable Complex Bid Offer Format if:

(i) The Final Physical Notification Quantity (qFPNuγ(t)) for the Generator Unit, u, has a value of zero for all times within the Period of Physical Operation; or

(ii) The start of the Period of Physical Operation and the end of the previous Period of Physical Operation are within the same Period of Market Operation;

(iii) Otherwise, CSUuγ for the first Imbalance Settlement Period, γ, within the Period of Physical Operation shall have a value of zero.

(b) CSUuγ shall have a value of zero for each other Imbalance Settlement Period, γ, falling wholly within the Period of Physical Operation, or in which the Period of Physical Operation starts or ends,

A.11.2.3 The Market Operator shall determine all No-Load Costs (CNLuγ) payable for each Generator Unit, u, in each Imbalance Settlement Period, γ, as follows:

(a) CNLuγ shall have a value of zero for each Imbalance Settlement Period, γ, falling wholly within the Period of Physical Operation or in which the Period of Physical Operation starts or ends, where:

(i) The Final Physical Notification Quantity (qFPNuγ(t)) for the Generator Unit, u, has a non-zero value for any time within that Imbalance Settlement Period;

(ii) The Metered Quantity (QMuγ) for the Generator Unit, u, has a value of zero for that Imbalance Settlement Period, γ.

(b) In all circumstances not listed in paragraph A.11.2.3(a):

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(i) Where, in accordance with section A.3.2, Complex Bid Offer Format data is to be used in respect of the first Bid Offer Acceptance, o, in an Imbalance Settlement Period, γ, falling wholly within the Period of Physical Operation, or in which the Period of Physical Operation starts or ends, CNLuγ shall have a value equal to the [Submitted No-Load Cost] submitted for the Generator Unit as part of that Complex Bid Offer Format, multiplied by the Imbalance Settlement Period Duration (DISP);

(ii) Where, in accordance with section A.3.2, Simple Format data is to be used in respect of the first Bid Offer Acceptance, o, in an Imbalance Settlement Period, γ, falling wholly within the Period of Physical Operation, or in which the Period of Physical Operation starts or ends, CNLuγ shall have a value of zero.

A.11.2.4 The Market Operator shall determine the Recoverable Start-Up Costs (CSURuγ) for each Generator Unit, u, in each Imbalance Settlement Period, γ, within the Period of Market Operation as follows:

(a) CSURuγ for the first Imbalance Settlement Period, γ, within the Period of Market Operation shall have a value equal to value of the [Submitted Start Cost] relating to the Warmth State at the start time of the Period of Physical Operation submitted for the Generator Unit as part of the most recently submitted valid Complex Bid Offer Format Data as at the Bid Offer Acceptance Time in respect of the first Bid Offer Acceptance, o, for which Complex Bid Offer Format data is to be used in accordance with section A.3.2, in that Imbalance Settlement Period, γ, if:

(i) The final Dispatch Quantity (qDuoγ(t)) for the Generator Unit, u, has a value of zero for all times within the Period of Market Operation; or

(ii) The start of the Period of Market Operation and the end of the previous Period of Market Operation are within the same Period of Physical Operation;

(iii) Otherwise, CSURuγ for the first Imbalance Settlement Period, γ, within the Period of Market Operation shall have a value of zero.

(b) CSURuγ shall have a value of zero for each other Imbalance Settlement Period, γ, falling wholly within the Period of Market Operation, or in which the Period of Market Operation starts or ends.

A.11.2.5 The Market Operator shall determine all Recoverable No-Load Costs (CNLRuγ) for each Generator Unit, u, in each Imbalance Settlement Period, γ, as follows:

(a) CNLRuγ shall have a value of zero for each Imbalance Settlement Period, γ, falling wholly within the Period of Market Operation or in which the Period of Market Operation starts or ends, where:

(i) The Final Dispatch Quantity (qDuoγ(t)) for the Generator Unit, u, has a non-zero value for any time within that Imbalance Settlement Period.

(b) In all circumstances not listed in paragraph A.11.2.5(a):

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(i) CNLRuγ shall have a value equal to the [Submitted No-Load Cost] submitted for the Generator Unit as part of the most recently submitted valid Complex Bid Offer Format Data as at the Bid Offer Acceptance Time in respect of the first Bid Offer Acceptance, o, in an Imbalance Settlement Period, γ, falling wholly within the Period of Market Operation, or in which the Period of Market Operation starts or ends, multiplied by the Imbalance Settlement Period Duration (DISP);

(ii) Where, in accordance with section A.3.2, Simple Format data is to be used in respect of the first Bid Offer Acceptance, o, in an Imbalance Settlement Period, γ, falling wholly within the Period of Market Operation, or in which the Period of Market Operation starts or ends, CNLRuγ shall have a value of zero.

[A.11.2.6] For the purposes of calculations under this Code the Market Operator shall calculate each value of Start-Up Costs (CSUuγ) for each Demand Side Unit, u, from the relevant value of Shut- Down Cost (CSDuγ) for the relevant Imbalance Settlement Period, γ, for that Demand Side Unit. The Market Operator shall set all values of No-Load Costs (CNLuγ) for Demand Side Units u to be zero for all Imbalance Settlement Periods, γ.

A.11.3 Determination of Contiguous Operating PeriodsA.11.3.1 The Market Operator shall determine the start and end of each Contiguous

Operating Period, k, for each Generator Unit, u, in each Billing Period, b, as follows:

(a) Subject to paragraph A.11.3.1(c), the start of a Contiguous Operating Period, k, will be:

(i) The start of the Imbalance Settlement Period, γ, during which the value for the Dispatch Quantity (qDuγ) of the Generator Unit, u, rises from zero;

(ii) The start of the first Imbalance Settlement Period, γ, within a Billing Period, if the value for the Dispatch Quantity (QDuγ) of the Generator Unit, u, was greater than zero at the end of the last Imbalance Settlement Period in the preceding Billing Period.

(b) Subject to paragraph A.11.3.1(c), the end of a Contiguous Operating Period, k, will be the earlier of:

(i) The end of the Imbalance Settlement Period, γ, during which the value for the Dispatch Quantity (qDuγ) of the Generator Unit, u, falls to zero; or

(ii) The end of the last Imbalance Settlement Period, γ, within a Billing Period.

(c) A Contiguous Operating Period, k, shall not end where the value for the Dispatch Quantity (qDuγ) of the Generator Unit, u, falls to zero but then rises from zero within the same Imbalance Settlement Period, but shall be treated as continuing during the period in which the value is zero.

A.11.4 Calculation of Fixed Costs Payments and Charges

Explanatory Note

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- Calculate all the operational costs arising out of balancing market actions. This is the sum of all no-load and start-up costs payable in the BM, as determined in the previous section, and the cost of delivered accepted offers and accepted bids, as determined by the price submitted by the participant for these offers and bids.

- This is calculated for all periods in a contiguous operating period, then summed.

A.11.4.1 The Market Operator shall calculate the Make-Whole Payment Operating Cost (COCMWPuk) for each Generator Unit, u, for each Contiguous Operating Period, k, in each Billing Period, b, as follows:

COCMWPuk=∑γ∈k (CNLuγ+CSU uγ+∑

o∑i

(PBOuβoiγ× (QAOLFuoiγ−QAOUNDELuoiγ ) )+∑o∑i

(PBOuβoiγ× (QABLF uoiγ−QABUNDELuoiγ )))where:

(a) CNLuγ is the No-Load Cost for Generator Unit, u, in Imbalance Settlement Period, γ;

(b) CSUuγ is the Start-Up Cost for Generator Unit, u, in Imbalance Settlement Period, γ;

[(c)] PBOuβoiγ is the Bid Offer Price for each individual Accepted Bid Quantity and Accepted Offer Quantity for Generator Unit, u, time stamped, β, as the last one submitted by the relevant Participant beforefor Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ;

(c)[(d)] QAOLFuoiγ is the Loss-Adjusted Accepted Offer Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ;

(d)[(e)] QABLFuoiγ is the Loss-Adjusted Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ;

(e)[(f)] QAOUNDELuoiγ is the Undelivered Accepted Offer Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ;

(f)[(g)] QABUNDELuoiγ is the Undelivered Accepted Bid Quantity for Generator Unit, u, for Bid Offer Acceptance, o, for Band, i, in Imbalance Settlement Period, γ.

Explanatory Note


- Calculate all balancing market revenues relevant to a make-whole payment. This is a sum of the cash flows calculated in previous sections, except for some additional charges which should not be considered in a make-whole payment (i.e. to ensure the unit isn’t made-whole for a charge which should stand to them.

A.11.4.2 The Market Operator shall calculate the Make-Whole Payment Revenue (CREVMWPuk) for each Generator Unit, u, for each Contiguous Operating Period, k, in each Billing Period, b, as follows:

CREVMWPuk=∑γ∈ k

(CIMBuγ+CPREMIUM uγ+CDISCOUNT uγ+CAOOPOuγ+CABBPOuγ+CCURLuγ )

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where:

(a) CIMBuγ is the Imbalance Component Payment or Charge for Generator Unit, u, in Imbalance Settlement Period, γ;

(b) CPREMIUMuγ is the Premium Component Payment for Generator Unit, u, in Imbalance Settlement Period, γ;

(c) CDISCOUNTuγ is the Discount Component Payment for Generator Unit, u, in Imbalance Settlement Period, γ;

(d) CAOOPOuγ is the Offer Price Only Accepted Offer Payment or Offer Price Only Accepted Offer Charge for Generator Unit, u, in Imbalance Settlement Period, γ;

(e) CABBPOuγ is the Bid Price Only Accepted Bid Payment or Bid Price Only Accepted Bid Charge, γ; and

(f) CCURLuγ is the Curtailment Charge for Generator Unit, u, in Imbalance Settlement Period, γ.

Explanatory Note


- If the revenues of the unit in the balancing market over a contiguous operating period are insufficient to cover their costs (primarily considering their explicit no-load and start-up costs which have not yet been considered in their revenues), the unit is made-whole to the required amount through this cash flow. Otherwise the value for this cash flow is zero.

A.11.4.3 The Market Operator shall calculate the Make-Whole Payment (CMWPuk) for each Generator Unit, u, for each Contiguous Operating Period, k, in each Billing Period, b, as follows:

CMWPuk=Max (COCMWPuk−CREVMWPuk ,0 )

where:

(a) COCMWPuk is the Make-Whole Payment Operating Cost for Generator Unit, u, in Contiguous Operating Period, k; and

(b) CREVMWPuk is the Make-Whole Payment Revenue for Generator Unit, u, in Contiguous Operating Period, k.

A.11.4.4 The Market Operator shall calculate the Fixed Cost Payment or Charge (CFCub) for each Generator Unit, u, in each Billing Period, b, as follows:

CFCub=∑k∈bCMWPuk−∑

γ ∈b(CNLRuγ+CSURuγ )

where:

(a) CMWPuk is the Make-Whole Payment for Generator Unit, u, in Contiguous Operating Period, k;

(b) CNLRuγ is the Recoverable No-Load Cost for Generator Unit, u, in Imbalance Settlement Period, γ; and

(c) CSURuγ is the Recoverable Start-Up Cost for Generator Unit, u, in Imbalance Settlement Period, γ.


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(b) A Trading Unit;



(e) A unit which has Priority Dispatch, which is non-dispatchable;

(f) An Autonomous Generator Unit.

A.12 IMPERFECTIONS CHARGES

A.12.1 Setting of Imperfections Charges ParametersA.12.1.1 The Market Operator shall report to the Regulatory Authorities at least [4

months] before the start of the Year, proposing values for the following parameters to be used in the calculation of Imperfections Charges for that Year:

(a) The Imperfections Price (PIMPy) in €/MWh for Year, y; and

(b) the Imperfections Charge Factor (FCIMPγ) for each Imbalance Settlement Period, γ, in Year, y.

A.12.1.2 The Market Operator's report must set out any relevant research or analysis carried out by the Market Operator and the justification for the specific values proposed. The report may, and shall if so requested by the Regulatory Authorities, include alternative values from those proposed and must set out the arguments for and against such alternatives.

A.12.1.3 The Market Operator shall publish the approved value(s) for each such parameter within [5 Working Days] of receipt of the Regulatory Authorities' determination or [two months] before the start of the Year to which they shall apply whichever is the later.

A.12.1.4 The Market Operator may, of its own accord or in response to a request from the Regulatory Authorities, make additional interim reports to the Regulatory Authorities during the Year, proposing revisions to the Imperfections Charge Factor in the event that the values as originally proposed do not provide for the adequate recovery of anticipated costs and such under recovery is such that it is not appropriate to include as an adjustment in subsequent Years.

A.12.1.5 The Market Operator shall publish the approved revised Imperfections Charge Factor, and the date and time on which it comes into effect, within [5 Working Days] of receipt of the Regulatory Authorities' determination.

A.12.2 Calculation of Imperfections ChargesA.12.2.1 The purpose of the Imperfections Charge is to recover the anticipated

Dispatch Balancing Costs (less Other System Charges), Make Whole Payments, any net imbalance between Energy Payments and Energy Charges and Capacity Payments and Capacity Charges over the Year, with adjustments for previous Years as appropriate.

A.12.2.2 The Market Operator shall calculate the Imperfections Charge (CIMPvγ) for each Supplier Unit, v, that is not a Trading Site Supplier Unit, in each Imbalance Settlement Period, γ, as follows:

CIMPvγ=Min(QMLF vγ ,0)×PIMP y×FCIMPγ

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where:

(a) PIMPy is the Imperfections Price for Year, y;


(c) FCIMPγ is the Imperfections Charge Factor for Imbalance Settlement Period, γ.

A.12.2.3 The Market Operator shall calculate the Imperfections Charge (CIMPvγ) for each Trading Site Supplier Unit, v, in each Imbalance Settlement Period, γ, as follows:

❑❑ (∑❑

❑❑∑❑

❑❑)❑❑❑❑

where:

(a) PIMPy is the Imperfections Price for Year, y;

(b) QMLFvγ is the Loss-Adjusted Metered Quantity for Supplier Unit, v, in Imbalance Settlement Period, γ;

(c) ∑❑

❑means the value for all Generator Units, u, in Trading Site, s, relevant to the Trading Site Supplier Unit;

(d) ∑❑

❑means the value for the single Supplier Unit, v, in Trading Site, s, in accordance with [paragraph in registration stating that Trading Sites may only have a single Supplier Unit]; and

(e) FCIMPγ is the Imperfections Charge Factor for Imbalance Settlement Period, γ.


[(a)] A Trading Site Supplier Unit.

[A.13] TESTING CHARGES

Explanatory note:

- The Granting of Testing Status is built into the rules through the Data Submission section. Which tariffs are used for different cases is outside the scope of the market rules, and depends on the tariff setting consultation referred to in the first section here.

A.12.3[A.13.1] Setting Testing TariffsA.12.3.1[A.13.1.1] If requested by the Regulatory Authorities, the relevant System

Operator shall report to the Regulatory Authorities proposing values for the Testing Tariffs at least [four months] before the start of the Year to which they shall apply. The System Operator's report must set out the justification for the specific values proposed. The report may, and shall if so requested by the Regulatory Authorities, include alternative values from those proposed and must set out the arguments for and against such alternatives.

[A.13.1.2] Each System Operator shall provide to the [Market Operator] at least [two months] prior to the start of each Year or [within 5 Working Days] of approval of the Testing Tariffs by the Regulatory Authorities whichever is the later, the

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Testing Tariff Data Transaction, which comprises a complete set of Testing Tariffs that have been approved by the Regulatory Authorities for each Generator Unit (other than Demand Side Units) that is registered within its Jurisdiction, for each Trading Period in the Year, y[, in accordance with Appendix K “Market Data Transactions”].

A.12.3.2[A.13.1.3] The [Market Operator] shall publish the approved value(s) for each parameter within [5 Working Days] of receipt of the Regulatory Authorities' determination or [two months] before the start of the Year to which they shall apply whichever is the later.

A.12.3.3[A.13.1.4] The System Operator may update the Testing Tariffs within the Year to which they apply subject to the prior approval of the Regulatory Authorities. If the Testing Tariffs are so updated, the System Operator shall provide the updated Testing Tariff Data Transaction to the [Market Operator] within [5 Working Days] of approval by the Regulatory Authorities.

A.12.3.4[A.13.1.5] The [Market Operator] shall publish each Year the schedule of Testing Tariffs and the detailed tariff methodology and periodically in the event that the Tariffs are updated within a Year.

A.12.4[A.13.2] Calculation of Testing ChargesA.12.4.1[A.13.2.1] The Market Operator shall calculate the Testing Charge (CTESTuγ)

for each Generator Unit, u, except for any Interconnector Error Unit, u, in each Imbalance Settlement Period, γ, for which it is Under Test as follows:

CTEST uγ=−Max (QMLF uγ ,0 )×PTESTTARIFFuγ

where:

(a) QMLFuγ is the Loss-Adjusted Metered Quantity for Generator Unit, u, Under Test in Imbalance Settlement Period, γ;

(b) PTESTTARIFFuγ is the Testing Tariff Price for Generator Unit, u, Under Test in Imbalance Settlement Period, γ, as set out in the schedule of Testing Tariffs.

A.12.4.2[A.13.2.2] The Market Operator shall calculate the Testing Charge (CTESTuγ) for each Interconnector Error Unit, u, in each Imbalance Settlement Period, γ, for which it is Under Test as follows:

If QMLFuγ>0 thenCTEST uγ=−Max (QMLF uγ ,0 )×PTESTTARIFFuγelseCTEST uγ=QMLF uγ×PTESTTARIFFuγ

where:

(a) QMLFuγ is the Loss-Adjusted Metered Quantity for Interconnector Error Unit, u, Under Test in Imbalance Settlement Period, γ;

(b) PTESTTARIFFuγ is the Testing Tariff Price for Generator Unit, u, Under Test in Imbalance Settlement Period, γ, as set out in the schedule of Testing Tariffs.

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A.13[A.14] RESIDUAL ERROR VOLUME CHARGES

A.13.1[A.14.1] PurposeA.13.1.1[A.14.1.1] The purpose of the Residual Error Volume Charge is to recover

costs in relation to the loss adjusted Residual Error Volume which is the residual energy calculated when total Loss Adjusted Metered Demand is deducted from total Loss Adjusted Metered Generation for each Jurisdiction. The Residual Error Volume Price is intended to cover the anticipated net imbalance over the Year, with adjustments for previous Years as appropriate.

A.13.2[A.14.2] Setting Residual Error Volume Charges ParametersA.13.2.1[A.14.2.1] The [Market Operator] shall report to the Regulatory Authorities at

least [4 months] before the start of the Year, proposing the following parameter to be used in the calculation of Imperfections Charges for that Year:

(a) The Residual Error Volume Price (PREVy) in €/MWh for Year, y.

A.13.2.2[A.14.2.2] The [Market Operator's] report must set out any relevant research or analysis carried out by the Market Operator and the justification for the value proposed. The report may, and shall if so requested by the Regulatory Authorities, include alternative values from those proposed and must set out the arguments for and against such alternatives.

A.13.2.3[A.14.2.3] The [Market Operator] shall publish the approved value for each such parameter within [5 Working Days] of receipt of the Regulatory Authorities' determination or [two months] before the start of the Year to which they shall apply whichever is the later.

A.13.3[A.14.3] Calculation of Residual Error Volume Charges A.13.3.1[A.14.3.1] The Market Operator shall calculate the Residual Error Volume

Charge (CREVvγ) for each Supplier Unit, v, which is not a Trading Site Supplier Unit, in each Imbalance Settlement Period, γ, as follows:

❑❑ (❑❑ ( (❑❑)❑❑❑❑) ) ( (❑❑ ) ( (❑❑)❑❑ (❑❑) ) )❑❑❑❑❑❑❑❑

where:

(a) RMVIPey is the Residual Meter Volume Interval Proportion for Currency Zone e in year y;

(b) PREVy is the Residual Error Volume Price for Year, y;

(c)[(b)] QMLFvγ is the Loss-Adjusted Metered Quantity for Supplier Unit, v, in Imbalance Settlement Period, γ; and

(d)[(c)] FNIEPvγ is the Non-Interval Energy Proportion Factor for Supplier Unit v, in Imbalance Settlement Period, γ.

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[A.15] CURRENCY ADJUSTMENT CHARGES

A.13.4[A.15.1] PurposeA.13.4.1[A.15.1.1] The purpose of the Currency Adjustment Charge is to recover costs

in relation to the anticipated variation between the dual currencies applied in the SEM over the Year, with adjustments for previous Years as appropriate where costs where under or over recovered.

A.13.5[A.15.2] Setting Currency Adjustment Charge ParametersA.13.5.1[A.15.2.1] The [Market Operator] shall report to the Regulatory Authorities at

least [4 months] before the start of the Year, proposing the following parameters to be used in the calculation of Currency Adjustment Charges for that Year:

(a) The Currency Cost Price (PCCy) in €/MWh for Year, y; and

(b) Values of the Currency Cost Charge Factor (FCCAγ) for each Imbalance Settlement Period, γ, in Year, y.

A.13.5.2[A.15.2.2] The [Market Operator's] report must set out any relevant research or analysis carried out by the Market Operator and the justification for the specific values proposed. The report may, and shall if so requested by the Regulatory Authorities, include alternative values from those proposed and must set out the arguments for and against such alternatives.

A.13.5.3[A.15.2.3] The [Market Operator] shall publish the approved value(s) for each such parameter within [5 Working Days] of receipt of the Regulatory Authorities' determination or [two months] before the start of the Year to which they shall apply, whichever is the later.

A.13.5.4[A.15.2.4] The [Market Operator] may, of its own accord or in response to a request from the Regulatory Authorities, make additional interim reports to the Regulatory Authorities during the Year, proposing revisions to the Currency Cost Charge Factor in the event that the parameters as originally proposed do not provide for the adequate recovery of anticipated costs and such under recovery is such that it is not appropriate to include as an adjustment in subsequent Years.

A.13.5.5[A.15.2.5] The Market Operator shall publish the approved revised Currency Cost Charge Factor, and the date and time on which it comes into effect, within [5 Working Days] of receipt of the Regulatory Authorities' determination.

A.13.6[A.15.3] Calculation of Currency Adjustment Charges A.13.6.1[A.15.3.1] The Market Operator shall calculate the Currency Adjustment

Charge (CCAvγ) for each Supplier Unit, v, which is not a Trading Site Supplier Unit, in each Imbalance Settlement Period, γ, as follows:

CCAvγ=Min(QMLF vγ ,0)×PCC y×FCCA γ

where:

(a) PCCy is the Currency Cost Price for Year, y;


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(c) FCCAγ is the Currency Cost Charge Factor in Imbalance Settlement Period, γ.

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