Commercial Mechanism
in SR Region
AVAILABILITY TARIFF(ABT)
(a)
(b)
(c)
CAPACITY CHARGE
ENERGY CHARGE
ADJUSTMENT FOR DEVIATIONS
(UI CHARGE)
(a)
= a function of Ex-bus MW avilability of power plant for the
day
declared before the day starts x SEB’s % share
.
(b)
= MWh for the day as per ex=bus drawal schedule for the
SEB
finalized before the day starts x Energy charge rate
=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)
(c)
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.
WHAT IS SETTLEMENT ?
• “ Settlement means finalisation of payment
bill after consumption”
• To be FAIR and EQUITABLE
• To RECOVER DUES at the EARLIEST
(Billing Cycle)
• TRANSPERANCY
• Dispute Resolution
• Reconciliation
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
On monthly basis :
REB to issue REA specifying % Avb, % Net Entitlement, %
SRLDC/Comml/IEGC/34
WEEKLY ENERGY ACCOUNTING:
WEEKLY CYCLE
ACTIVITIES
MONDAY MORNING
THURSDAY NOON
REB
Tues day
: 00 HRS OF EACH MONDAY TO 24 HRS;
OF THE THE FOLLOWING SUNDAY
: SEM DATA DOWNLOADED TO DCD
: DCD DATA LOADED TO A LOCAL PC
: DATA SENT TO RLDC via E-MAIL
(LATEST TUESDAY MORNING )
: RLDC CONVEYS PROCESSED DATA TO
: 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
SETTLEMENT SYSTEM
For the day: 0000 hrs. to 2400 hrs.
Central Generating Stations
1
2
3
MW
Ex-Bus Capability
(Forecast)
SEB-A’s share
SEB-B’s share
SEB-C’s share
x1
____
x2
___
x3
___
a1
b1
c1
a2
b2
c2
a3
b3
c3
For a particular 15 minute time block
SEB-A’s requisition
SEB-B’s requisition
SEB-C’s requisition
CGS’s schedule
SRLDC/Comml/IEGC/37
a’1
b’1
c’1
___
x1’
a’2
b’2
c’2
___
x2’
a’3
b’3
c’3
___
x3’
1000
MW
Forecast ex-bus capability of power plant
800
Declared Capability for which Capacity charges Gen.Sched. for which Energy charges
Are recieveable by ISGS
Are recieavable by ISGS
600
SEB - A’s entitlement (40%)
400
200
Schedule for which Energy charges
Are payable by SEB- A
Entitlement for which Capacity charges
Are payable by SEB-A
0
0
6
12
18 HRS
24
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
= x1’ * Energy charge rate of CGS-1
4
Total capacity charge payable by SEB-A for the day
= a1 * capacity charge rate of CGS-1
+ a2 *
-doCGS-2
+ a3 *
-doCGS-3
Total Energy charge payable by SEB-A for the day
= (a1’) * Energy charge rate of CGS-1
( 4 )
+ (a2’) *
-doCGS-2
( 4 )
+ (a3’) *
-doCGS-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 = X1 MWh.
Excess injection = (X1 – x1’ ) 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 = a1’+a2’+a3’ = 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
Previous definition of Capacity
charges
% Availability for ISGS =
n
∑ SOC
i=1
i
+CL
100
h x IC
(1-aux/100)
i
Where SOC = Sent Out capability for the I th block
n = total no. of blocks in the period under consideration
aux = normative % auxiliary consumption as % of gross Gen.
CL = Gross MWh of capacity kept closed on a/c of Gen. Sched order
IC= installed capacity in MW
h = no. of hours during the period = n/4
% Availability forms the basis for calculations
Present Definition Capacity
charges
N
DCi/ {NxICx(100-Auxn) }%
10000
i=1
% Availability =
Where DCi = Average Declared Capacity for i th day of the period in MW
N = Total no. of days during the period
Auxn = Normative Auxiliary Consumption as % of gross Gen.
IC= installed capacity in MW
% Availability forms the basis for calculations
N
PLF =
SGi/ {NxICx(100-Auxn) }%
10000
i=1
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
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.
Fixed/Variable
Name Of
ISGS
Aux.
Consumption
RSTPS
8.43%
Variable
Charges
(Ps)
85.96
NLC II/1
10.00%
67.99
NLC II/2
10.00%
94.61
NLC TPS 1
(EXP)
9.50%
98.11
TALCHERSTAGE II
8.50%
44.02
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
Incentive as per old norms
PLF = scheduled energy
IC x no. of hours
Incentive rate up to 90%PLF =
50% Annual Fixed charges
Energy per anum at target PLF
Incentive rate beyond 90%PLF =
25% Annual Fixed charges
Energy per anum at target PL
Incentive as per New norms
• Flat rate of 25ps/u
• For ex-bus Schedule Energy in Excess of
ex-bus energy corresponding to Target
PLF
Unscheduled Interchanges (UI)
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 01.01.03 up to 31.03.04.
UI rate (Paise per KWh)
Average Frequency of time block
50.5 Hz. and above
0.0
Below 50.5 Hz. and upto 50.48 Hz.
5.6
Below 49.04 Hz. and upto 49.02 Hz.
414.4
Below 49.02 Hz.
420.0
Between 50.5 Hz. and 49.02 Hz. Linear in 0.02 Hz. step
UI rate w.e.f 01.04.04 to 30.09.04
UI rate (Paise per KWh)
Average Frequency of time block
50.5 Hz. and above
0.0
Below 50.5 Hz. and upto 50.48 Hz.
8.0
Below 49.04 Hz. and upto 49.02 Hz.
592.0
Below 49.02 Hz.
600.0
Between 50.5 Hz. and 49.02 Hz. Linear in 0.02 Hz.
step
• UI rate w.e.f 01.10.04
UI rate (Paise per KWh)
Average Frequency of time block (Hz,)
Below
Not below
----50.50
0.0
50.50
50.48
6.0
50.48
50.46
12.0
------------------------49.84
49.82
204.0
49.82
49.80
210.0
49.80
49.78
219.0
49.78
49.76
228.0
------------------------49.04
49.02
561.0
49.02
----570.0
(Each 0.02 Hz. Step is equivalent to 6.0 paise/kWh in the 50.549.8 Hz. Frequency range and to 9.0 paise/kWh in the 49.8-49.0
Hz. Frequency range).
Under drawl by SEB-A
Over Gen. By ISGS-1
UI import from IR-1
Regional Pool
System
frequency
Under gen. By ISGS-2
UI Export to IR-2
Over drawl by SEB-B
No one to one correspondence
Energy transactions of UI from/to Pool
UI
Rate
Operation of Pool
Separate Pool a/cs operated by RLDCs on behalf of REBs for UI,
IRE and Reactive charges
Payable by SEB-B
Payable by IR-2
at its UI rate
Payable by ISGS-2
Regional Pool
Receivable by ISGS-1
Receivable by SEB-A
(up to DC)
No one to one correspondence
Receivable by IR-1
at its UI rate
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
OR BELOW
VOLTAGE IS 97%
•
CUMULATIVE REACTIVE EXCHANGE WHILE VOLTAGE IS
ABOVE.
103% OR
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 06-01-01 TO 0837 HRS OF 15-01-01
NP-0185-A
91858.5
99968.5
39195.5
06-01-01
00 51
+21.57 48
04 19
+20.61 23
08 00
+24.95 00
12 71
+24.38 52
16 00
+23.37 00
20 00
+25.75 00
NP-0185-A
94117.2
+21.68 50
+20.80 19
+24.95 00
+23.98 30
+23.52 00
+25.32 00
99968.5
+21.71
+21.05
+25.09
+23.81
+22.87
+25.40
40313.5
49
00
00
13
00
00
+21.33
+21.35
+24.38
+24.03
+21.66
+25.37
07-01-01
00 59
+20.94 54
04 33
+20.05 38
08 00
+22.99 06
12 85
+20.93 51
16 07
+20.14 01
20 05
+23.62 08
NP-0185-A
96172.2
+21.01 59
+20.17 37
+23.10 00
+20.65 21
+20.53 00
+23.23 16
99968.5
+20.79
+20.49
+22.81
+20.79
+20.72
+23.25
41236.9
58
28
00
00
00
27
+21.05
+20.90
+22.94
+19.89
+20.66
+23.40
08-01-01
Computed Mwh data
230 kV Neyveli line at Pondicherry
CTR = 600 PTR = 2091
PO-02 NP-0185-A
06-01-01
2833.8145 0.0
1402.6
0000
27.061722
27.199728
27.237366
26.760618
0100
26.911171
26.547337
26.735525
25.907490
0200
26.196047
25.932583
26.522243
26.622612
0300
26.509697
26.321507
25.844761
25.644024
0400
25.857307
26.095678
26.409328
26.798256
0500
26.785711
27.839575
28.567242
28.780525
0600
29.458008
29.269817
30.072762
30.198221
0700
31.126625
31.314816
31.289724
31.214447
0800
31.302271
31.302271
31.477915
31.603374
0900
31.603374
31.289724
31.402639
31.553190
1000
30.775339
31.201902
31.565735
31.515553
1100
31.603374
30.198221
30.424049
30.235861
1200
30.587147
30.085308
29.872025
30.148039
….
…..
…..
…..
…..
2300
27.726660
27.350279
26.760618
26.346600
Active energy
ENERGY ACCOUNTING USING SPECIAL ENERGY METER FOR 15-12-00
-------------------------------------------TIME PONDY YANAM Net Drawal
PO-02
PO-06
IN Mwhr
-------------------------------------------00:00
+31.77
+1.83
+33.60
00:15
+31.68
+1.83
+33.51
00:30
+32.06
+1.85
+33.90
00:45
+31.59
+1.77
+33.36
01:00
+31.11
+1.54
+32.65
01:15
+30.76
+1.62
+32.39
01:30
+30.94
+1.57
+32.51
01:45
+31.06
+1.79
+32.85
02:15
+31.04
+1.85
+32.88
-----------------------------------------------------------------------------------23:15 +27.38 +1.90 +29.27
23:30 +27.00 +1.91 +28.90
23:45 +26.48 +1.89 +28.37
-------------------------------------------TOTAL +3060.16 +176.12 +3236.28
---------------------------------------------
REACTIVE ENERGY CHARGE :
PAYABLE FOR :
1.
2.
VAR DRAWALS AT VOLTAGES BELOW 97%
VAR INJECTION AT VOLTAGES ABOVE 103%
RECEIVABLE FOR:
1.
2.
VAR INJECTION AT VOLTAGES BELOW 97%
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
RATE:
@ Rs. 48.62/MVArh (for 2004-05)
Basic Rate : 4 paise/kvArh ( for the year 2000-01 )
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
A.
SOUTHERN REGIONAL ELECTRICITY BOARD
ABT based U.I. Account
FOR THE PERIOD 25.10.2004 to 31.10.2004
ABSTRACT OF UNSCHEDULED INTERCHANGES ( UI
figures in Rs. Lakhs)
Utilities
KPTCL
PONDY
KSEB
GOA
NLC MINES
NLC II - 1
NLC II - 2
WR
Total
UI Payable
1172.68548
93.76627
62.34445
35.18813
35.16922
8.36314
4.33511
4.13279
1415.98459
Utilities
APTRANSCO
TNEB
ER
RSTPS
Talcher
NLC-1-EXP
PG-HVDC
Total
UI Receivable
759.45210
310.25146
297.73327
72.80693
34.27954
14.82175
10.05435
1499.39940
NOTE:
1.
Revised UI rates w.e.f. 1/10/2004 vide CERC
(Terms and Conditions of Tariff) (First Amendment)
Regulations 2004.
2.
MAPS & KGS not covered under ABT; hence UI
reduced to zero, under all conditions.
3.
UI for Talcher STPS Stage-II has been
calculated at ER frequency.
4.
IR Exchanges:
i)
Metering points – For WR it is Chandrapur South
Bus.
- For ER it is Gazuwaka East Bus &
Talcher stage I&II I/C bus.
ii)
UI for IR exchanges with ER has been
calculated at SR frequency as per the decision taken
in Special TCC meeting held at Bangalore on
23.08.2004.
iii) UI charges with WR and ER has been taken as
first charge, as per decision taken in Special
Committee meeting held on 17.12.2002.
ABSTRACT OF UNSCHEDULED INTERCHANGES
(restricting to the lesser of the two as per the
126th SRE Board decision).
A.
(UI figures in Rs. Lakhs)
Utilities
KPTCL
PONDY
KSEB
GOA
NLC MINES
NLC II - 1
NLC II - 2
WR
TOTAL
UI Payable
1172.68548
93.76627
62.34445
35.18813
35.16922
8.36314
4.33511
4.13279
1415.98459
Utilities
APTRANSCO
TNEB
ER
RSTPS
Talcher
NLC-1-EXP
PG-HVDC
TOTAL
UI Receivable
706.73400
288.71506
297.73327
67.75297
31.89999
13.79288
9.35642
1415.98459
SOUTHERN
FOR
REGIONAL
ELECTRICITY
Reactive Energy Charges Account
THE PERIOD 25-10-2004 to 31-10-2004
A.REACTIVE
ENERGY
CHARGES
WITH
(
Beneficiaries
(as
BOARD
Payable
to Pool
THE
POOL
Amount
in
:
Rupees)
Receivable
Beneficiaries from Pool
APTRANSCO
2275540
KPTCL
2939838
KSEB
565089
TNEB
3138559
B.NET REACTIVE ENERGY CHARGES BETWEEN BENEFICIERIES:
per decision in the 132nd meeting of SRE Board)
BY
BENEFICIERY
APTRANSCO
KPTCL
KSEB
TNEB
PONDY
GOA
FROM
BENEFICIERY
KPTCL
TNEB
PONDY
APTRANSCO
KSEB
TNEB
GOA
KPTCL
TNEB
APTRANSCO
KPTCL
KSEB
APTRANSCO
KPTCL
AMOUNT RECEIVABLE
in Rupees
0
0
0
10,526
22,443
69,931
0
0
348,399
92
0
0
3,705
0
RPU 2003-04
Weekly UI a/c files
RPU 2004-05