Regional Commercial Accounting-TYPES & METHODOLOGY

By: S.KEJRIWAL , Executive Engineer

ERPC, Kolkata

Various Types of Accounting:

Deviation Account Reactive Energy (VAR) Account Congestion Charge Account Regional Energy Account Regional Transmission Account Regional Transmission Deviation

Account

REGIONAL TRANSMISSION DEVIATION ACCOUNT

Data required Approved Injection or Drawal Approved Additional Medium Term

Injection or Drawal- MTOA Approved Short Term Injection or

Drawal- STOA Actual MW Injection or Drawal in a

time block Prevalent PoC rate

CalculationTotal Approved Injection in a time block = ( LTOA + MTOA + STOA injection) = X i

(say)

Total Approved Drawal in a time block = ( LTOA + MTOA + STOA Drawal)= Xd (say)

INJECTION DEVIATION:

Net MW injection in a time block = Ai (say)IF Ai > Xi , Total Injection Deviation , Di = Ai – Xi

IF Ai < Xi , Total Injection Deviation , Di = 0

DRAWAL DEVIATION:

Net MW drawal in a time block = Ad (say)IF Ad > Xd , Total Drawal Deviation , Dd = Ad – Xd

IF Ad < Xd , Total Drawal Deviation , Dd = 0

Calculation – Generator ( only Long term Customers)

Injection PoC rate = Ri (say)

Withdrawal PoC rate = Rd (say)

INJECTION DEVIATION ( POSITIVE DEVIATION ):

IF Di > 0.2*Xi ,Transmission Deviation Charges = 0.2*Xi* Ri (Payable by Long term customers)Additional Deviation Charges = (Di - 0.2*Xi)*1.25*Ri (Payable by Generator)

DRAWAL DEVIATION ( NEGATIVE DEVIATION ):

Dd = Ad – Xd = Ad , Since Xd = 0Transmission Deviation Charges = 1.25*Ad*Rd (Payable by Generator)

Calculation – Generator ( IPPs)Injection PoC rate = Ri (say)

Withdrawal PoC rate = Rd (say)

INJECTION DEVIATION ( POSITIVE DEVIATION ):

IF Di > 0.2*Xi ,Transmission Deviation Charges = 0.2*Xi* Ri (Payable by Generator)Additional Deviation Charges = (Di - 0.2*Xi)*1.25*Ri (Payable by Generator)

DRAWAL DEVIATION ( NEGATIVE DEVIATION ):

Dd = Ad – Xd = Ad , Since Xd = 0Transmission Deviation Charges = 1.25*Ad*Rd (Payable by Generator)

Calculation – Beneficiaries/StatesInjection PoC rate = Ri (say)

Withdrawal PoC rate = Rd (say)

DRAWAL DEVIATION ( POSITIVE DEVIATION ):

IF Dd > 0.2*Xd ,Transmission Deviation Charges = 0.2*Xd * Rd

Additional Deviation Charges = (Dd - 0.2*Xd) * 1.25* Rd

INJECTION DEVIATION ( NEGATIVE DEVIATION ):

Di = Ai – Xi = Ai , Since X = 0Transmission Deviation Charges = 1.25*Ai*Ri

IllustrationSuppose, in a time block ( for a beneficiary, IPP )Ai = 150 MW Xi = 120 MW

Injection PoC rate, Ri or = Rs 80 / MW

Total Injection Deviation, Di = (150 – 120 ) = 30 MW

Deviation beyond permitted limit = Di - 0.2Xi= 30-24 = 6 MW

Transmission Deviation Charges = 0.2*Xi*Ri = 24*80 = Rs 1920

Additional Deviation Charges = 1.25*6*80 = Rs 600

Total Deviation Charges = Rs (1920+600)= Rs 2520

Illustration

Ai = 165.41MWH Xi = 538.82 MW = 134.705 MWH

PoC rate, Ri = Rs 197.8 / MWH

Total Injection Deviation, Di =(165.41–134.705)= 30.704 MWH

Deviation beyond permitted limit = Di- 0.2Xi = 30.704-26.941 = 3.763 MWHTransmission Deviation Charges = 0.2*Xi*Ri = 26.941*197.8 = Rs 5328.93Additional Deviation Charges = 1.25*3.763*197.8 = Rs 930.40Total Deviation Charges = Rs 6259.33

Utility/Generator

Date Time Block

SESA STERLITE

22.06.2015 17:00 Hrs

Illustration

Ai = 0 MWH, Xi = 622.05 MW = 155.5125 MWHAd = 4.1548 MWH , Xd = 0

PoC rate, Ri = Rd = Rs 197.8/ MWH

Total Injection (Positive) Deviation, Di = 0 MWHTotal Drawal (Negative) Deviaiton, Dd = 4.1548 MWH **Total Deviation Charges = 1.25*Dd* Rd = 1.25*4.1548*197.8 = Rs 1027.28(** Deviation Charges to be paid by the Generator i,e BARH STPS )

Utility/Generator

Date Time Block

BARH 16.06.2015 11:00 Hrs

Illustration

Ai = 130.618 MWH Xi = 503.88 MW = 125.97 MWHPoC rate, Ri = Rs 222.7/ MWH

Deviation permitted = 0.2*Xi = 0.2* 125.97 = 25.194 MWH

Total Injection Deviation, Di =(130.618–125.97)= 4.648 MWH (which is less than quantum of deviation permitted without levy of additional charges)

** Transmission Deviation Charges = Di * Ri = 4.648*222.7 = Rs 919.41(** Deviation Charges to be paid by the beneficiaries of TEESTA V

in proportion to their share in TEESTA V )

Utility/Generator

Date Time Block

TEESTA V 25.07.2015 00:45 Hrs

DRAWAL LTOA MTOA STOA TOTALFSTPP-I &

II203.97

0 171.28

1406.49

KhSTPP- I 116.49KHSTPP-II 28.98TSTPP-I 299.72TSTPP-II 200FSTPP-III 78.32TEESTA 103.75CHUKHA 41.01

TALA 42.92BARH 91.99COAL 28.06TOTAL 1235.21 0 171.28

TOTAL APPROVED DRAWAL, Xd (in MW) 1406.49

APPROVED DRAWAL

Utility/Generator

Date Time Block

GRIDCO 28.02.2015 18:15 Hrs

APPROVED

INJECTION

LTOA MTOA STOA TOTAL

1.82 MW

HIRAKUD HPS

TO CHATTISGARH

30 MWJSL

(Orissa) to JSL

(Haryana)

1.82 MW

HIRAKUD HPS

TO CHATTISGARH

80.63 MWAS

FURNISHED BY ERLDC

112.45 MW

TOTAL APPROVED INJECTION, Xi (in MW) 112.45

APPROVED INJECTION

Utility/Generator

Date Time Block

GRIDCO 28.02.2015 18:15 Hrs

Utility/Generator

Date Time Block

GRIDCO 28.02.2015 18:15 Hrs

Ad = 397.126MWH , Ai = 0 Xd = 1406.49 MW = 351.623 MWH Xi = 112.45 MW = 28.1125 MWH

PoC rate, Ri = Rs168.9 / MWH , Rd = Rs 148.9 / MWH

Deviation permitted = 0.2Xd = 0.2*351.623 = 70.3245 MWH

Total Drawal Deviation, Dd =(397.126–351.623)= 45.504 MWH (which is less than quantum of deviation permitted without levy of additional charges)

Total Injection Deviation, Di = 0 MWH

Transmission Deviation Charges = Dd * Rd = 45.504*148.9 = Rs 6775.5

RTDA—Some Facts RPC issues the statement by 15th of every

month CTU raises the bill on the payable entities

within 3 days of issuance of statement by RPC CTU collects the transmission deviation charges

and distributes the same to Transmission licensees

Application of Transmission charges for infirm power injection & Start-up power drawal as per 3rd Amendment of PoC Regulation

Amendment of Deviation Settlement Regulations vide CERC Order dated 20.01.2015 in petition no RP/06/2014 filed by Tripura State Electricity Corporation Ltd.

OBJECTIONS RAISED: 5.1.(iii) The Charges for the Deviation for the under

drawals by the buyer in a time block in excess of 12% of the schedule or 150 MW, whichever is less, shall be zero

Unintended underdrawal due to sudden load crash, increase in hydro generation or network congestion

Restoration of system takes time Non- acceptance of request for downward revision of

schedule in totality

7.(3) The Additional Charges for the Deviation for the over drawals by the buyer in a time block in excess of 12 % of the schedule or 150 MW, whichever is less

Generation Outage Network congestion

Prayers of TSECL The limit of deviation for under drawal and over-

injection as 12% of 150MW if the schedule is less than 150 MW

Exclusion of liability of ADC during contingency / force majeure

Introducing continuous trading in PX Initiating requisition based scheduling of hydro

generating stations Deferment of implementation of DSM Regulations may be made for over drawal in excess

of 12% of the schedule or 150 MW, whichever is higher instead of less for NER states

Apprehension of MPPMCL: Large state with a demand of

10000MW Integration of Renewables Multiple penalization Sudden tripping of bigger size units Technical minimum constraints

Submission of NLDC DSM need of the hour Helpful in secure operation of grid Improvement of freq profile Utilities adhering to schedule UI volume gone down Availability of sufficient avenues Grid security and safety of paramount

importance

Observation of CERC Contingency plan in advance by DISCOMS DSM introduced after grid disturbance of

30th & 31st July, 2012 Grid freq not the lone parameter for secure

grid operation UI not a route for trading Freq band gradually tightened in previous

UI regime

Amendments made to DSM (w.e.f 02.02.2015) :

Relaxation of Regulation 5.1.iii of DSM- For utilities having schedule of 400 MW or below, Deviation Charges shall be receivable as

for under-drawal upto 48 MW for over-injection upto 48 MW

Relaxation of Regulation 7.3 of DSM- For utilities having schedule of 400 MW or below, Additional Deviation Charges shall be payable as

Additional charges for deviation shall be based on percentage of deviation worked out with reference to schedule of 400 MW

Illustration

Actual Injection = 41.9636 MWHScheduled Injection = 168 MW = 41.9862 MWHDeviation = 5.9774 MWH, Freq = 49.92HzRate of Deviation charges = Rs 3447.2As per previous regulation,Over injection permitted = 0.12*41.9862 = 5.038 MWH

(which is less than quantum of deviation)

Deviation Charges receivable = Rs 5.038*3447.2

As per amended regulation,Over injection permitted = 48 MW = 12 MWH (which is more

than the quantum of deviation)

Deviation Charges receivable = Rs 5.9774*3447.2

Utility/Generator

Date Time Block

TEESTA V 07.05.2015 14:00 Hrs

Illustration Actual Injection = 23.3454 MWHScheduled Injection = 322 MW = 80.6 MWHDeviation = 57.254 MWH, Freq = 49.99HzRate of Deviation charges = Rs 1988.4As per previous regulation,Under-injection permitted = 0.12*80.6 = 9.672 MWHUnder-injection beyond permitted limit = 57.254 – 9.672 =

47.582 MWHAdditional Deviation Charges payable = Rs 85957.4

Utility/Generator

Date Time Block

GMR 20.05.2015 18:45 Hrs12

-15%

3% of Sch*20% of Dev Rate of that time block= 0.03*80.6*0.2*1988.4= Rs961.59

15-2

0%

5% of Sch*40% of Dev Rate of that time block= 0.05*80.6*0.4*1988.4= Rs3205.3 Ab

ove

20 %

(47.582-8% of Sch)*100% of Dev Rate of that time block= 41.134*1*1988.4=Rs81790.85

Illustration Actual Injection = 23.3454 MWHScheduled Injection = 322 MW = 80.6 MWHDeviation = 57.254 MWH, Freq = 49.99HzRate of Deviation charges = Rs 1988.4As per amended regulation,Under-injection permitted = 48 MW = 12 MWHUnder-injection beyond permitted limit = 57.254 – 12 =

45.254 MWHAdditional Deviation Charges payable = Rs 79237

Utility/Generator

Date Time Block

GMR 20.05.2015 18:45 Hrs12

-15%

3% of 100*20% of Dev Rate of that time block= 0.03*100*0.2*1988.4= Rs1193.04

15-2

0%

5% of 100*40% of Dev Rate of that time block= 0.05*100*0.4*1988.4= Rs3976.8 Ab

ove

20 %

(45.254-8% of 100)*100% of Dev Rate of that time block= 37.254*1*1988.4=Rs 74067.9

THANK YOU