W.BENGAL

BIHAR

JHARKHAND

ORISSA

Sikkim

132 kV Sahupuri-Karmanasa S/C -

132 kV Rihand - Sonenagar

220 kV Dehri -Sahupuri

220 kV Balimela (Orissa) -Upper Sileru

220 kV Birpara-Salakti D/C line 1999

132 kv Rihand-Garwah

220 KV Korba (MP) – Budhipadar (Orissa)

Tala

Allahabad

B’nggon

Raipur

VizagKolar

Rourkella

Talcher

YEAR ISGS Thermal GEN

(MU)

EXPORT(MU)

TOTALSAVING(RS. CR)

1995-96 9584 854 691996-97 10628 652 751997-98 13585 2389 3091998-99 14063 3438 4611999-00 16381 5931 7352000-01 18228 6773 7552001-02 18279 8721 9432002-03 20460 9382 961

Savings of ER Constituents Due to Export

National GridNational Grid

CTU – INTER REGION

CTU_WEST

CTU_SOUTH

CTU_NORTH

CTU_EAST

CTU_NE

STU

STU

STU

RLDC

NLDC

RLDC

RLDC

RLDC

RLDC

ERLDC:POWERGRIDERLDC:POWERGRID

BULK POWERTRANSACTION

POWERGRID EHV

W.RN.R

NER SR

C.S.GENERATORS

STATE SYSTEMS STATE SECTOR

GENERATORS

Operating Frequency

49 to 50.5 Hz

Frequency band for safe operation of Steam Turbine as

recommended in IEGC

Pre ABT Settlement system

• The payment to Central Generating Station by a constituent - proportion to total energy drawal – Recommendation of K.P.Rao Committee Report.• Both Fixed and Variable charge was payable as per energy drawal• Based on Monthly Regional Energy Account- REA • Conventional Meter Readings • Fixed cost recoverable with deemed generation ( generation not made available)•Incentive payable after accounting for deemed generationAlthough a two part tariff- Single part for constituent

Inadequacies • Non-utilization of Utilities’ Surplus Power

– No incentive for Maximization of own/ IPP/captive generation within a State as the cost of power paid is based on pooled rate of ISGS stations.

– No effective commercial mechanism for pricing deviations from schedule.

• Dumping of surplus power at High Freq– Forced Backing down/ Reserve Shut down– Deemed generation for backing down

• Non-utilization of embedded IPP/Licensee surplus Power.– Administrative problems and no commercial arrangements for utilization of this

power. Any surplus remains unutilized.

• Non-utilization of Pumped Storage Scheme– No commercial mechanism to draw cheap off peak power for pumping. Bhira

PSS/Kadamkadai is not being utilized in the pumping mode.

Contd..

• Inability to Despatch Generation according to Grid requirement.– Generation of Licensees cannot be despatched as per Grid requirements due to

commercial problems.

• Curtailment of Bilateral Transactions due to Grid Indiscipline.– Overdrawing State(s) deliberately increase drawls and cause frequency to dip

below 48.5 Hz so that inter-regional transactions are terminated.

• Absence of Merit Order Operation– As payments are based on drawls and not on shares/schedules, fixed

cost are not perceived as sunk costs.

Inherent Disadvantage• No incentives for generators /utilities to respond to

dispatch orders for issues like frequency control– No Incentive for helping the grid– No disincentive for hurting the grid

• No signal to generators to match availability with system needs

• Did not promote Grid Discipline• No signal for trading of power.

Overall economy was lost.

EFFECT• Backing down of cheaper CS generation

– Caused high per unit cost

• Dumping of energy by other utility at high frequency/off peak hours-

– additional fixed cost liability for generation & transmission.

• More payment Liability

- Even when helped the grid

Ultimate EffectUltimate Effect• Grid Indiscipline-

• Low Frequency during peak• High Frequency during off peak

• Control Instructions• Subjective decisions• Not based on overall economy

• Perpetual Operational & Commercial Dispute amongst Utilities/Central Generators

• Poor Supply quality to consumers/industries

• Damage to equipments• Shifting of Industries/Investments

Why ABT?Why ABT?•Promote competition, efficiency and Promote competition, efficiency and economy- Merit order dispatcheconomy- Merit order dispatch

•Competitive market based systemCompetitive market based system•Possibility of trading on a non-firm Possibility of trading on a non-firm basis- selling of capacity entitlementbasis- selling of capacity entitlement

•Facilitating Grid discipline- Incentive Facilitating Grid discipline- Incentive and disincentive for deviationand disincentive for deviation

Capacity Ch.Capacity Ch. + + Energy Ch.Energy Ch. UIUI

A + B A + B C C

TOPICS DEALT IN THE ORDERTOPICS DEALT IN THE ORDER• TARGET AVAILABILITYTARGET AVAILABILITY

• CRITERIA FOR INCENTIVECRITERIA FOR INCENTIVE

• PROCEDURE FOR PREVENTION OF GAMINGPROCEDURE FOR PREVENTION OF GAMING

• PROLONGED OUTAGESPROLONGED OUTAGES

• UI CHARGES AND FREQUENCY VARIATIONUI CHARGES AND FREQUENCY VARIATION

• SETTLEMENT OF UI ACCOUNTSETTLEMENT OF UI ACCOUNT

• TREATMENT OF UNALLOCATED CAPACITIESTREATMENT OF UNALLOCATED CAPACITIES

Availablity Based Tariff (ABT)• Links commercial mechanism & Grid Operation• Promotes grid operation• ABT Structure – 3 parts of tariffs

A. Capacity charges– Proportionate to entitlements (not actual drawals)– Full recovery at target availability (not PLF)– Incentives linked to Availability (80%) and PLF (77%)– Incentives half of per KWh fixed charges at target availability /

capped at 21 p/u

B. Energy charges– Payable for schedules (not as per actual drawals)

C. Unscheduled Interchange– Payable for deviations from schedules– Linked to average frequency for 15 minute time block (graph

enclosed)

.

Central Govt. CEA

CERC REB State Govt SERC CTU RLDC SEB/STU SLDC

ISTS & ISGS

X= L- G

Control AreaControl Area