ERTAC EGU MACE/MACW Case Study

December 10, 2012

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MACE/MACW: Unrealistic Growth of CoalIssue: Discovered unrealistic

creation of new coal unitsMACE: 4 new unitsMACW: 1 new units

Reminder: “Proof of Concept” Run used 2010 growth rates that were predicted prior to boom in cheap gas

Preliminary sensitivity runs using AEO 2011 growth rates suggest that no new coal facilities will be built in the MACE and MACW regions

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MACWLILC

NYC

New Units: Due to Peak or Base Growth?Important question to ask: Why are the new units generated? Two

possibilities:1 - A few high demand hours needing capacity, or:2 - Base load is lacking throughout the year

Useful reports for analysisCalc Generation Params CSV and;Hour Specific Growth Rate (HSGR) v. Average Future Year Growth Rate (AFYGR)

graphs• Contain all hours of the year for each region/fuel bin• Can identify hours with positive AFYGRs

Demand Generation Deficit CSV• Shows only hours with lacking capacity for a region/fuel bin and by how much the

generation lacks• For region/fuel bins that have a problem

– If it is during peak hours this file will have 20 or less entries– If it is a base load issue this file will have 1000’s of entries

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HSGR v. AFYGR Explanation (MACW Coal Ex.)

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Hours from 1/1 00:00-12/31 11:00

Hours from highest base year activity to lowest

Peak HoursTransition Hours

Non-peak Hours

Hourly Specific Growth Rates

Adjusted Future Year Growth Rate

MACE and MACW

2010 2011

Annual Growth Rates 0.958426 0.903495

Peak Growth Rates 1.065554 0.748965

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Growth Rates

Base Fuel Switch

Retirement

New Units

Future

MACE 23 4 12 4 11

MACW 47 0 1 1 47

Planned Units

MACW Coal: HSGR v. AFYGR

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HSGR consistently > AFYGR indicative of a lack of retirements

AFYGR > 1 at peak hint at, but don’t confirm generic unit creation

MACE Coal: HSGR v. AFYGR

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AFYGR consistently > HSGR indicative of many retirements

AFYGR > 1 at peak hint at, but don’t confirm generic unit creation

DiagnosisHSGR v. AFYGR Graphs

MACE appears to be a base load problemMACW appears to be a peak problem

Demand Generation Deficit CSV confirmsHours needing additional coal generation

MACE: ~4,500 hoursMACW: 2 hours

New units were being generated inMACE due to base load lackingMACW due to a peak load problem

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Sensitivity RunsConducted 4 sensitivity runs

Updated growth rates:2011 coal growth rates are substantially lower than 2010So we updated peak and base growth rates to 2011

Nominal heat rates:The software allows you to:

• manually input an annual unit level heat rate or; • use BY data to calculate unit level heat input

Many units had nominal heat rates that were higher than the calculated rates, meaning they ran less efficiently than they could have in the future year

So we removed all manually inputted nominal heat rates

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Region Updated Growth Rate

Better Unit Efficiency Estimates

Both

MACE X X X

MACW X

ResultsNew generic coal units:

Better Unit Efficiency Estimates:Both regions can use existing plants to cover the generation of one new 600

MW plantGrowth rate impact:

Reduction in predicted growth of coal reduced the need for two new 600 MW plants

But wait… there is still 1 new coal unit… but there is more

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Region V1.0 Updated Growth Rate

Better Unit Efficiency Estimates

Both

MACE 4 2 3 1

MACW 1 0

Regional boundaries changed from AEO 2010 to AEO 2011Essentially MACE expanded into MACWMACW has excess existing coal capacity since it only had a

peaking problemConclusion: We have preliminary results showing that

updating regional boundaries will remove the last generic coal plant

Regional Boundaries

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2010 2011

LILCNYC

NYCW

NYLI

MACW

RFCE

ConclusionsUpdating inputs with newer and better information

cleans up the new coal unit issueRather than taking outputs as given ERTAC team used

the models traits to fix the problemState input: Determined that results were unrealisticTransparency: Determined cause of the problem – for

instance whether capacity was needed at peak or baseLow Operational Cost: Only staff and computing time

needed to conduct sensitivities to troubleshoot the problematic results, no high consulting fees are necessary

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