Planning Principles & Load DispatchingNatthajak Chomsiridechanan

Medium-term Operation Planning SectionGeneration Operation Planning Department

Power System Control and Operation Division

Natthajak.c@egat.co.th tel. 02-436-2183

IPP&SPP Seminar16 November 2015

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• Operation Planning Objectives• Operation Planning Criteria• Demand Forecasting• Outage Scheduling• Limitations• Generating Capacity & Energy• Emergency Preparations

Outline

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• Reliable supply of electricity– Adequacy– Security (N-1)

• Quality Standard- Voltage- Frequency

• Reasonable Production cost• Environment Awareness

Operation Planning Objectives

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• Long Term– Generation outage plan– Tariff calculation– Financial analysis & Budget– Fuel supply plan– Problem warning

• Medium Term– Energy resources planning for typical day and holiday season– Plant commissioning program Considerations– Determine Transmission Outage– Place secondary fuel orders in advance of desired delivery date

• Short Term– 48 periods plan for day ahead planning

Operation Planning Criteria

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• 1-5 Years (Monthly Basis)• Economics (GDP)• EPPO data; Residential, Business, Industrial Growth• Historical Data (PEA, MEA and direct sales)

• Monthly Energy from Long Term forecasting• 1-4 Months (Daily Basis)• Historical Data (Pattern)• Long Holidays and Festivals

• 1 Day (Half-Hour Basis)• 5 Region – CAC, NEC, SAC, NAC, MAC• Weather Forecasting• Historical Data (Pattern)

Demand ForecastingLong Term

Medium Term

Short Term

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Outage Scheduling• Light Load Days base on calendar year • Table of AP Weight base on marginal cost• Peak and Off-Peak in accordance with historical

load pattern

EGAT Noticed

• IPP 7 Years • SPP 3 Years

Rolling Outage Plan

• Monthly Outage (3 Months ahead)• Weekly Outage• Daily Availability Declaration / Prior Notice

Outage Notice

• 5 Years ahead• Generation plan considered together e.g. marginal

cost, gas shortage

Shutdown Schedule

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Outage SchedulingFully DispatchAvailability Payment WeightDay ahead

0 20 40 60 80

100 120 140 160

Mon-Sat: Peak Mon-Sat: Off-peakSunday and Holiday

Long Holiday

Paym

ent A

vera

ge (%

)

Summer Rainy Winter 7

EGAT & IPP

Mechanism

Dispatch Plan

Outage SchedulingPartially DispatchPeak and Off-Peak notice (Capacity Payment)Month ahead

10,000

12,000

14,000

16,000

18,000

20,000

22,000

24,000

0:00

2:

00

4:00

6:

00

8:00

10

:00

12:0

0 14

:00

16:0

0 18

:00

20:0

0 22

:00

0:00

MW

Weekday - Summer Weekday - Winter

10,000

12,000

14,000

16,000

18,000

20,000

22,000

24,000

0:00

2:

00

4:00

6:

00

8:00

10

:00

12:0

0 14

:00

16:0

0 18

:00

20:0

0 22

:00

0:00

MW

Sunday - Summer Sunday - Winter 8

SPP

Mechanism

Dispatch Plan

Dispatching Limitations

Must Run Unit

• System Securities (N-1)

Must Take

• Purchase Contract• Fuel Supply Contract

Irrigation• EGAT’s Hydro Generation

Dispatchable

• Efficiency & Fuel Price

TransmissionSystem

Capability

Minimum take

BB, SK,SNR, VRK, RPB, LTK

Cost Rank

26%

25%

7%

42%

Ratio of Total Capacity

58%

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East Gas- Natural Gas Fields- Gas Separation Plant- LNG 760 MMSCFD (Up to 1000 MMSCFD in Q4 2016)

- Maximum Supply 1,300 MMSCFD- Wobbe Index 1160-1280 BTU/SCF

West Gas- Natural Gas Fields- Maximum Supply 1,260 MMSCFD- Heating Value >803 BTU/SCF- Partially Supply: Yadana+Yetagun or Yadana+Zawtika- Totally Shutdown in case of Yadana gas shortage

Limitation (Gas Supply)

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Limitation (Gas Pipeline)

South BKK

Wangnoi

Bang Pakong

EPEC

C1,2

RPCL

North BKK

C3

TECO

GPSCGlowIPP

Myanmar Gas

SPP Navanakorn, Rangsit U-Thai

NongSaeng

Gulf Power

RB

SB+NBWest < 459 MMSCFDMix < 609 MMSCFD

SPP Nakhon Sawan

WN+GPG+EPEC+GNS+GUT

< 904 MMSCFD

SPP Korat

RA#6-NB,SB Non-EGAT 25 MMSCFD

BVW1-RA#6Non-EGAT 81 MMSCFD

RA#6

Common HeaderEast Gas

SBE < 220 MMSCFD

“Gas Pipeline Configuration from 23 Sep 2015 Onward” 11

#1 #3 #2 #4

Generating Capacity & EnergyTotal Capacity 37,412 MW @Nov15

2015 Peak Demand 27,346 MW@14:02 hrs 11 Jun 2015

2015 Energy 181,879 GWh

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EGAT38.3%

IPP37.7%

SPP15.8%

Foreign8.2%

Energy by Owner (GWh)

EGAT IPP SPP Foreign (FIPP+TNB+EDL)

EGAT41.2%

IPP37.1%

SPP13.3%

Foreign8.5%

Capacity by Owner (MW)

EGAT IPP SPP Foreign (FIPP+TNB+EDL)

Generated Energy by Fuel

Gas66.76%

Coal20.11%

FO1.00%

DO0.07%

Hydro9.73%

Renew + Other2.32%

2014 Energy Generation and Purchase 177,580 GWh

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Gas Supply Shortage• Secondary Fuel

– Fuel Oil; 5-7 days inventory level – Diesel Oil; 3 days inventory level

• Fuel Oil Exercise– Dispatch/Plant request– 3 times/year/gas turbine

• Transportation from fuel depot to power plant– Oil Transportation planning

Emergency Preparations

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Q & A Thank you

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