global aggregation working group 15 th september 2010

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Global Aggregation - Recap

What is Global Aggregation?

Process of providing an aggregation for all registered Suppliers

Includes aggregation of Host Suppliers

Current implementation means Host Supplier calculated by difference

Error Supplier Unit in the SEM

Not just Host Supplier volumes but also other errors included

Data Aggregation

NHH Meters(STS only)

Readings

AUFs and EUFs

Profiled Demand for NHH

customers

Generator Output

Tran Loss factors

Units delivered to

BSP in Each

Jurisdiction

HHM metered

units

Meter data processing


HH Meters

ReadingsDifference

Residual volume assigned to NIEES /ESBN using Error Supplier Units

Metered or profiled volumes are uplifted in DA to reflect distribution line losses


Data Aggregation

Readings

AUFs and EUFs

Profiled Demand for NHH

customersInclude DN

LLFs

Generator Output

HHM metered

unitsInclude DN

LLFs



HH Meters

Readings

Variance is ‘smeared’ across Suppliers, method to be determined through SEMO

Metered or profiled volumes are uplifted in DA to reflect distribution line losses (reports show both vols)

Variance

Tran Loss factors

Units delivered to

BSP in Each

Jurisdiction


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Causes of imbalance?

Power Stations &interconnectors

Transmission Network Distribution Networks Customers(end users)

Physical inaccuracyBack door suppliesInterconnector lossesMeter errors

Meter errorsUmetered embedded generationTheftLine losses

Transformer losses

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Power Stations &interconnectors

Transmission Network Distribution Networks Customers(end users)

Data Errors

Umetered SupplyProfilesEnergisation StatusTLAFs DLAFs

Station aggregation rules

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Elexon experience of Global Aggregation;

Incorrect profiles of non-interval meters considered chief contributor;

Modification 34_09 developed with a view to smearing residual volume

across all suppliers, taking account of each suppliers share of non-interval

metered consumers;

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Mod 34.09 raised by ESB CS

Mod proposed separation of SU into Interval SU and Non-Interval SU

Raised at Mods Meeting 24 (29.09.09)

Mods Panel recommended setting up Working Group to explore further

Terms of reference for Working Group circulated, Nov 2009

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Working Group 1, held on 19th November 2009.

Presentations & Discussion –

ESB CS suggested assigning ESU to non-competing Party under the Code;

MDPs presented on impact on systems;

Actions –

SEMO & RA to meet to further develop options;

ESB CS & NIE to provide estimation of error;

Mods Panel to decide if impact assessments should be sought;

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SEMO & RA met December 1st to develop options paper;

Four options written up and circulated –

Option A – recovered through SEMO balancing cost;

Option B – smear across Suppliers based on annual factors;

Option C – smear across Supplier based on monthly factors;

Option D – as set out in modification proposal;

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Working Group 2, held on 23rd February 2010.


Suppliers presented on magnitude of actual error;

SEMO & MDPs presented results of impact assessments;

MRSO proposed option E, further enhancement on option C;

Actions –

SEMO & MDPs to meet to further review options D and E;

SEMO to impact assess options A+ and E;

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Meeting between MRSO, NIE T&D and SEMO took place on March 5th;

Further review of Options D and E;

Option E confirmed as

Aggregation for Supplier Units as normal;

Inclusion of a % value for each Trading Period;

% value will indicate at a MW level the proportion of the aggregation that is

made up of non-interval metering;


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Working Group 3, held on 27th April 2010.


SEMO presented on MDP meetings and further impact assessments;

EirGrid presented on TUoS impacts;

Actions –

SEMO to issue consultation on options A+ and E;

TSO to review implementation of Option A for TUoS;

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Consultation document issued on June 17th;

Participants asked to express preference between Option A+ and Option E;

Responses welcomed on discarded options B, C and D;

Nine responses received to Consultation

Five responses favoured Option E (2 Participants, 3 service providers)

Three responses favoured Option A+

One response recommended either option

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Working Group 4, held on 26th August 2010.


Recap and review of consultation responses;

Full impact assessment on SEMO systems is approx 1200 hours or €210 K

Noted flexibility in Option E to allow for implementation in one jurisdiction

ahead of the other;

Stressed importance of decision;

Consensus reached on recommendation of Option E;

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Metered Generation Loss Adjusted

Metered Demand by Supplier Unit

MGLF - NDLF Error Supplier Unit

Current Design

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MGLF - NDLF Error Supplier Unit

Option E Design



MGLF - NDLFResidual Meter

Volume & Smearing


ANINDeh

NIEPvhNDvhRMVIPy

AINDeh

NIEPvhNDvhRMVIPyREVLFehNDAvh 1

1

After calculation of residual error volume;

Allocated across all Suppliers in the SEM;

Residual Meter Volume Interval Proportion – sets how much of the error

volume is allocated based on a Suppliers interval metered customers;

Non-Interval Energy Proportion – advises what portion of the aggregated

Metered Demand is based on non-interval metered customers;

global aggregation working group 15 th september 2010

Documents

global aggregation recap

e slide

data aggregation readings

e semo

e option e

modification proposal

working group

error supplier units