1. GRID STATUS – PRE - ABT Very wide Frequency fluctuations
48.0Hz to 52 Hz.
Low Grid Voltages
400kV going down up to 330kV
Frequent Grid Disturbances
Sub-Optimal Operation
High Technical loss
Overdrawals at low frequency – might is right
Grid Operation on fire fighting instead of Optimisation & Economy

2. Components of inter-utility tariff (Pre – ABT Mechanism)
Fixed charges
Interest on loans
Depreciation
O & M charges
Return on equity
Interest on Working Capital
Energy charges (fuel cost)
Incentives
Surcharge & other levies
No charge for reactive energy

3. Unscheduled Interchange (UI)
Payment to Inter State Generating Stations (ISGS) from beneficiaries under Availability Based Tariff (ABT)
Capacity charges
Energy charges
Unscheduled Interchange (UI)

4. CAPACITY CHARGE
Capacity charge will be related to ‘availability’ of the generating station and the percentage capacity allocated to the state. ‘Availability’ for this purpose means the readiness of the generating station to deliver ex-bus output expressed as a percentage of its rated ex-bus output capability.

5. ENERGY CHARGE
Energy charges shall be worked out on the basis of a paise per kwh rate on ex-bus energy scheduled to be sent out from the generating station as per the following formula
Energy charges = Rate of energy charges (paise/kwh) x Scheduled Generation (ex-bus MWh)

6. UNSCHEDULED INTERCHANGE (U I) :
Variation in actual generation / drawal with respect to scheduled generation / drawal shall be accounted for through Unscheduled Interchange (UI).
UI for generating station shall be equal to its total actual generation minus its scheduled generation.
UI for beneficiary shall be equal to its total actual drawal minus its total scheduled drawal.

7. UNSCHEDULED INTERCHANGE (U I) :
UI shall be worked out for each 15 minute time block.
Charges for all UI transactions shall be based on average frequency of the time block.
UI rates shall be frequency dependent and uniform throughout the country.

9. UI RATE Rate of Unscheduled Drawal/Injection Frequency (Hz) Rate (p/u)
Above 50.5
50.0
150
49.8
210
49.0 and below
570

10. AVAILABILITY BASED TARIFF
CAPACITY CHARGE
ENERGY CHARGE
ADJUSTMENT FOR DEVIATIONS
(U I CHARGE)
(A) = a function of the Ex-Bus MW availability of Power Plant for the day declared before the day starts x SEB’s % allocation from the plant
(B) = MWh for the day as per Ex-Bus drawal schedule for the SEB finalised before the day starts x Energy charge rate
(C) = Σ (Actual energy interchange in a 15 minute time block – scheduled energy interchange for the time block) x UI rate for the time block
TOTAL PAYMENT FOR THE DAY = (A) + (B) ± (C)

11. FEATURES : No complication regarding deemed generation.
(A) and (B) do not depend on actual plant generation / drawal. No metering required for this as they are based on off-line figures. All deviations taken care of by (C)
No complication regarding deemed generation.
Perpetual incentive for maximizing generation and reducing drawal during deficit, but no incentive to over generate during surplus.
ESC TO EXIT

12. TOTAL UI AMOUNT DISBURSED:- 2753 CR AVG WEEKLY TRANSACTION:- 61 MU
UI IN SR (FROM 01/01/03 TO 07/01/07)
TOTAL UI TURNOVER : MU
TOTAL UI AMOUNT DISBURSED: CR
AVG WEEKLY TRANSACTION:- 61 MU
AVG WEEKLY UI AMOUNT DISBURSED:- 13 CR

13. SUMMARY OF UI – 190 WKS (FROM 01/JAN/03 TO 07/JANUARY/07)AP
KAR
KER TN
PONDY
Total UI exported(-) / Imported(+) in MUs
-3674
5213
283
1819
-260
Total amount paid in Crores Rs.
-528
983
-81
458
-51
Average rate of UI in paise/unit
144
189
285
252
195

14. UI EXCHANGES AND AVG. RATES IN RESPECT OF DIFFERENT CONSTITUENTS IN SR
817MU
2659MU
5164MU
1337MU
5046MU
658MU AP
KAR
KER TN
111MU
949MU

17. IR EXCHANGES OF SR IN THE FORM OF UI
TRANSACTION WITH WR
TRANSACTION WITH ER
Energy Imported
919 MU
(IMPORT BY SR)
985 MU
Net Saving to each SR and WR/ER Constituents due to differential tariff
Rs Cr.
Rs Cr.
Energy Exported
763 MU
(EXPORT BY SR)
450 MU
ESC TO EXIT