Settlement System under ABT Regime -Prepared by -V.Balaji, -Chief Manager(comml), -SRLDC, Bangalore -Presented by -P.Bhaskara Rao -DGM (comml)

WHAT IS SETTLEMENT ? “ Settlement means Closing the payment/receipt/adjustment process of bill for the period under consideration” To be FAIR and EQUITABLE To RECOVER DUES at the EARLIEST (Billing Cycle) TRANSPERANCY Dispute Resolution Reconciliation

Capacity charge: Capacity charge is based on Annual Fixed Charge and will be related to availability of generating station. Availability means the readiness of the generating station to deliver ex-bus output expressed as a percentage of its rated ex-bus output capability. Energy charge: Energy charge is related to the scheduled ex-bus energy to be sent out from the generating station and will be worked out on the basis of paise per KWh.

AVAILABILITY TARIFF(ABT) (a)CAPACITY CHARGE (b)ENERGY CHARGE (c)ADJUSTMENT FOR DEVIATIONS (UI CHARGE) (a)= a function of Ex-bus MW availability of power plant for the day declared before the day starts x SEB’s % share. (b)= MWh for the day as per ex=bus drawl schedule for the SEB finalized before the day starts x Energy charge rate (c)=Σ(Actual energy interchange in a 15 min time block – scheduled energy interchange for the time block) x UI rate for the time block. TOTAL PAYMENT FOR THE DAY = (a) + (b)± ( c)

SETTLEMENT SYSTEM For the day: 0000 hrs. to 2400 hrs. Central Generating Stations 1 23 Ex-Bus Capability x1x2x3 (Forecast) __________ SEB-A’s sharea1a2a3 SEB-B’s shareb1b2b3 SEB-C’s sharec1c2c3 For a particular 15 minute time block SEB-A’s requisition a’1a’2a’3 SEB-B’s requisition b’1b’2b’3 SEB-C’s requisition c’1c’2c’3 _________ CGS’s schedule x1’x2’x3’ MW SRLDC/Comml/IEGC/37

1000 MW HRS24 Forecast ex-bus capability of power plant SEB - A’s entitlement (40%) Entitlement for which Capacity charges Are payable by SEB-A Schedule for which Energy charges Are payable by SEB- A Declared Capability for which Capacity charges Are recieveable by ISGS Gen.Sched. for which Energy charges Are recieavable by ISGS

SETTLEMENT SYSTEM Total capacity charge payable to CGS-1 for the day = x1 * capacity charge rate of CGS-1 Total Energy charge payable to CGS-1 for the day = x 1 ’ * Energy charge rate of CGS-1 4 Total capacity charge payable by SEB-A for the day = a 1 * capacity charge rate of CGS-1 + a 2 * -do- CGS-2 + a 3 * -do- CGS-3 Total Energy charge payable by SEB-A for the day = (a 1 ’) * Energy charge rate of CGS-1 ( 4 ) + (a 2 ’) * -do- CGS-2 ( 4 ) + (a 3 ’) * -do- CGS-3 ( 4 ) All capacity charge and Energy charge payments to be made by SEBs directly to CGS. SRLDC/Comml/IEGC/38

SETTLEMENT SYSTEM Actual (metered) injection of CGS-1 in the time block = X 1 MWh. Excess injection = (X1 – x 1 ’ ) MWh. 4 Amount payable to CGS-1 for this =(X1-x1’) * pool price for the block. 4 SEB-A’s scheduled drawl for time block = a 1 ’+a 2 ’+a 3 ’ = a’ MW (ex-CGS Bus) SEB-A’s NET drawal schedule = (a’ – Notional Transm. Loss) MW = (a’ – Notional Transm. Loss) = A’ MWH 4 Actual (metered) net drawal of SEB-A during time block = A MWH Excess drawal by SEB-A = (A-A’) MWh. Amount payable by SEB-A for this = (A-A’) * pool price for the block. All above payments for deviations from schedules to be routed through a pool A/C operated by RLDC SRLDC/Comml/IEGC/39

AVAILABILITY Availability in relation to a generating station for any period means the average of the DCs for all the days during that period expressed as a percentage of the installed capacity of generating station minus normative auxiliary consumption in MW and shall be computed as per the following formula:

Present Definition Capacity charges % Availability = i=1 N DC i / {NxICx(100-Aux n ) }% Where DC i = Average Declared Capacity for i th day of the period in MW N = Total no. of days during the period Aux n = Normative Auxiliary Consumption as % of gross Gen. IC= installed capacity in MW % Availability forms the basis for calculations i=1 N SG i / {NxICx(100-Aux n ) }% PLF =

Recovery of Annual fixed charges 100% recovery if % Availability >=Target Availability - Pro-rata reduction if %Avb<T.Avb. - Target Avb. For Fixed ch recovery - Target PLF for incentive -Both to be Notified by CERC -Financial Year forms the basis for calculations ISGS Target Avb. Target PLF RSTPS 80% 80% NLC 75% 75%

Monthly Capacity charges receivable by an ISGS: 1 st Month = (1xACC1)12 2 nd Month = (2xACC2-1ACC1)12 …. …. 12 th month = (12xACC12-11ACC11)12 where ACC1,ACC2…….ACC12 = Annual capacity charges corresponding to the cum. Availability up to the corresponding month. Monthly Capacity charges payable by a beneficiary : 1 st Month = (1xACC1xWB1)12 2 nd Month = (2xACC2xWB2-1ACC1xWB1)12 …. …. 12 th month = (12xACC12xWB12-11xACC11xWB11)12 where WB1,WB2…..WB12 = Weighted average % share up to the corresponding month.

Name Of ISGS Aux. Consumption Variable Charges (Ps) RSTPS7.93%85.96 NLC II/110.00%67.99 NLC II/210.00%94.61 NLC TPS 1 (EXP) 9.50%98.11 TALCHER- STAGE II 7.50%44.02 Fixed/Variable

Energy charges The Energy Charges Payable by beneficiary to the ISGS = Variable Charge of ISGS X Requisition of beneficiary from The ISGS The Energy Charges Receivable by ISGS from beneficiaries = Variable Charge of ISGS X Despatch schedule of ISGS

Flat rate of 25ps/u For ex-bus Schedule Energy in Excess of ex-bus energy corresponding to Target PLF Incentive as per existing norms

Settlement Systems* On weekly basis : For seven day period ending on penultimate Sunday RLDC to furnish Scheduling & Metering data to REB Sectt. by Thursday noon REB Sectt. to issue Weekly UI a/c by Tuesday Pool a/c operated by RLDC Settlement for UI on weekly basis All accounts open for 20 days SRLDC/Comml/IEGC/34

Settlement System contd.. On monthly basis : REB to issue REA specifying % Avb, % Net Entitlement, % Energy charges, Wt. Avg. Ent. for Tr. Ch. etc. Capacity and Energy Charges, Incentive etc. –billed directly by ISGS based on REA issued by REB

WEEKLY ENERGY ACCOUNTING: WEEKLY CYCLE: 00 HRS OF EACH MONDAY TO 24 HRS; OF THE THE FOLLOWING SUNDAY ACTIVITIES MONDAY MORNING: SEM DATA DOWNLOADED TO DCD : DCD DATA LOADED TO A LOCAL PC : DATA SENT TO RLDC via (LATEST TUESDAY MORNING ) THURSDAY NOON: RLDC CONVEYS PROCESSED DATA TO REB Tues day: WEEKLY UI a/c & Reactive charges issued BY REB BILLING Cap. Charge : BILLED MONTHLY based on DAILY DC BY ISGS ENERGY CHARGE: BILLED MONTHLY based on DAILY DRAWL SCHEDULES ISSUED BY RLDC UI a/c Paid/Disbursed as per UI a/c issued by REB REACTIVE a/c

Variations in actual generation/drawal and scheduled generation /drawal are accounted through UI. This is a frequency linked charge which is worked out for each 15 minute time block. Charges for all UI transaction, based on average frequency have following rate of paise per KWh from up to UI rate (Paise per KWh) Average Frequency of time block 50.5 Hz. and above 0.0 Below 50.5 Hz. and upto Hz.5.6 Below Hz. and upto Hz Below Hz Between 50.5 Hz. and Hz. Linear in 0.02 Hz. step Unscheduled Interchanges (UI)

UI rate w.e.f to UI rate (Paise per KWh) Average Frequency of time block 50.5 Hz. and above 0.0 Below 50.5 Hz. and upto Hz.8.0 Below Hz. and upto Hz Below Hz Between 50.5 Hz. and Hz. Linear in 0.02 Hz. step

UI rate w.e.f UI rate (Paise per KWh) Average Frequency of time block (Hz,) BelowNot below (Each 0.02 Hz. Step is equivalent to 6.0 paise/kWh in the Hz. Frequency range and to 9.0 paise/kWh in the Hz. Frequency range).

Energy transactions of UI from/to Pool Over Gen. By ISGS-1 Under drawl by SEB-A UI import from IR-1 Under gen. By ISGS-2 No one to one correspondence System frequency UI Rate Regional Pool Over drawl by SEB-B UI Export to IR-2

Operation of Pool Separate Pool a/cs operated by RLDCs on behalf of REBs for UI, IRE and Reactive charges Regional Pool Payable by ISGS-2 Payable by SEB-B Payable by IR-2 at its UI rate Receivable by ISGS-1 (up to DC) Receivable by SEB-A Receivable by IR-1 at its UI rate No one to one correspondence No cross adjustments allowed between the constituents

Where do SEMs come into picture? Only measuring Deviations from Schedule i.e. UI To measure 15 min block-wise Energy and Frequency Issues concerned : -Specifications -Location criterion -Main/Check/Standby philosophy

SEMs Specification Static type Composite meter Highest accuracy available in the power industry 3 Phase – 4 wire connections/measurement Direct measurement in whrs and varh on the CT/PT secondaries –110 V Ph to Ph /63.51 V Ph – N –1 amp or 5 amp –VA burden not more than 10 on any of the phases Works on real time clock No calibration required

FEATURES OF SPECIAL ENERGY METERS : ACCURACY : 0.2 S AS PER OEC -687, 1992 STATIC, TOTALLY TAMPER - PROOF, SEALED FOR LIFE GALVANIC ISLATION AND SURGE SUPRESSION TWO STANDARD MODELS : 110V, 1A AND 110V, 5A NON - VOLATILE MEMORY FOR 10 DAYS HARMONICS FILTERED OUT AND ONLY FUNDAMENTAL ENERGY RECORDED ALL MEASUREMENTS, RECORIDNG IN SECONDARY QUANTITIES. CT AND VCT RATION APPLIED IN REGIONAL COMPUTATION NET ENERGY ( WH) EXCHANGE IN EACH 15 MIN. BLOCK CUMULATIVE WH TRANSMITTAL AT EACH MIDNIGHT AVERAGE FREQUENCY IN EACH 15 MIN. BLOCK CUMULATIVE REACTIVE ENERGY EXCHANGE WHILE VOLTAGE IS 97% OR BELOW CUMULATIVE REACTIVE EXCHANGE WHILE VOLTAGE IS 103% OR ABOVE.

FEATURES OF SPECIAL ENERGY METERS : contd…. HIGH-ACCURACY OF INTERNAL CLOCK: ONE MINUTE/MONTH,WITH RESTRICTED ADVANCE/ RETARD FACILITY TAGGING OF DATA WITH DATE, TIME METER NO. IDENTIFICATION OF TIME BLOCK WHEN VT SUPPLY DISTRUBED NO SEPARATE AUXILIARY SUPPLY ; ONLY OPTICAL COUPLER FOR DATA COLLECTION ( WEEKLY) DISPLAYS TO APPRISE THE SUBSTATION OPERATOR AS TO WHAT IS BEING RECORDED IN METERS MEMORY

Raw data WEEK FROM 0000 HRS OF TO 0837 HRS OF NP-0185-A NP-0185-A NP-0185-A

Computed Mwh data 230 kV Neyveli line at Pondicherry CTR = 600 PTR = 2091 PO-02 NP-0185-A …. ….. …..…..…

Active energy ENERGY ACCOUNTING USING SPECIAL ENERGY METER FOR a typical day TIME PONDY YANAM Net Drawal PO-02 PO-06 IN Mwhr : : : : : : : : : : : : TOTAL

REACTIVE ENERGY CHARGE : PAYABLE FOR : 1.VAR DRAWALS AT VOLTAGES BELOW 97% 2.VAR INJECTION AT VOLTAGES ABOVE 103% RECEIVABLE FOR: 1.VAR INJECTION AT VOLTAGES BELOW 97% 2.VAR DRAWAL AT VOLTAGES ABOVE 103% APPLIED FOR VAR EXCHANGES BETWEEN : A)BENEFICIARY SYSTEM AND ISTS - THROUGH A POOL ACCOUNT B)TWO BENEFICIARY SYSTEMS ON INTER-STATE TIES - BY THEMSELVES Rs /MVArh (for ) Basic Rate : 4 paise/kvArh ( for the year ) 5% ESCALATION PER YEAR

Issues in Reactive Energy charges Deficit in pool (SR & ER) -due to continuous High voltages in SR Surplus in Pool (NR &WR) Utilization of Accruals Disputes in payments between Beneficiaries for Reactive charges in Inter-state Lines

SOUTHERN REGIONAL ELECTRICITY BOARD ABT based U.I. Account FOR A TYPICAL WEEK NNOTE : 1. MAPS & KGS not covered under ABT; hence UI reduced to zero, under all conditions. IR Exchanges: - Metering points – For WR it is Chandrapur South Bus. - For ER it is Gazuwaka East Bus & Talcher stage I&II interconnecting bus. ii) UI for IR exchanges with ER has been calculated at ER frequency. iii) UI charges with WR and ER has been taken as first charge, as per decision taken in Special Committee meeting held on

A. ABSTRACT OF UNSCHEDULED INTERCHANGES ( UI figures in Rs. Lakhs) UtilitiesUI PayableUtilitiesUI Receivable KPTCL TNEB KSEB APTRANSCO PONDY ER NLC_II_ RSTPS NLC_II_ GOA TALCHER_II NLC_I_EXP WR TOTAL TOTAL

A. ABSTRACT OF UNSCHEDULED INTERCHANGES (restricting to the lesser of the two as per the 126 th SRE Board decision). (UI figures in Rs. Lakhs) UtilitiesUI PayableUtilitiesUI Receivable KPTCL TNEB KSEB APTRANSCO PONDY ER NLC_II_ RSTPS NLC_II_ GOA TALCHER_II NLC_I_EXP WR TOTAL TOTAL