severe winter weather resource outage analysis chad thompson operations working group september 24...
DESCRIPTION
3 Lesson Learned from Feb 2011 Event was to bring units on-line before freezing weather hits (Jan 23) Alternative fuel commitments need to be made as early as possible (preparation for gas curtailments) (Feb 6) Some fuel restrictions cannot be predicted (Feb 7) Brief HistoryTRANSCRIPT
Severe Winter Weather Resource Outage AnalysisChad ThompsonOperations Working GroupSeptember 24 2014
2
• ROS and WMS have been tasked with evaluating early RUC activity in anticipation of severe winter weather and observed unit start-up failures, trips, and derates
• WMS created a RUC Task Force to also investigate early RUC instructions
• ERCOT was asked to look at the data to determine if correlations to temperature and unit outages exists
• ERCOT believes there is a need to procure additional online generation capacity in anticipation of severe winter weather
Background
3
• Lesson Learned from Feb 2011 Event was to bring units on-line before freezing weather hits (Jan 23)
• Alternative fuel commitments need to be made as early as possible (preparation for gas curtailments) (Feb 6)
• Some fuel restrictions cannot be predicted (Feb 7)
Brief History
4
• ERCOT investigated concepts with input from stakeholders– New Forced Outages* VS Wind Chill– New Forced Outages* VS Daily Wind Chill
changes– New Forced Outages* VS Daily Min Temperature
changes• Data used is for the 2013/2014 Winter
Season (Dec-Feb)• Given the geographic diversity of the ERCOT
Grid, results were separated based on Load Areas
ERCOT Assessment
*Note: Data used is from ERCOT Outage Scheduler
5
6
• Background on Data– Daily Maximum MW that were forced out– Coldest observed Wind Chill– Lowest observed Air Temperature
• Note that these 3 items may not have been coincidental
ERCOT Assessment
7
0
100
200
300
400
500
600
700
<20 20~30 30~40 40~50 >50
MW
s
Daily Min Wind Chill ( � F)
Average New Generation Forced Out VS. Wind ChillWinter 2013/2014
NORTH/NRTHC/EAST COAST STHRN/STHC WEST/FWEST
Forced Outages VS. Wind Chill
8
0
100
200
300
400
500
600
700
800
<(-20) (-20)~(-10) (-10)~0
MW
s
Wind Chill Change from Previous Day ( � F)
Average New Generation Forced OutVS. Daily Wind Chill Change
Winter 2013/2014
NORTH/NRTHC/EAST COAST STHRN/STHC WEST/FWEST
Forced Outages VS. Daily Wind Chill Change
9
0
100
200
300
400
500
600
700
800
900
<(-20) (-20)~(-10) (-10)~0
MW
s
Air Temp Change from Previous Day ( � F)
Average New Generation Forced OutVS. Daily Air Temperature Change
Winter 2013/2014
NORTH/NRTHC/EAST COAST STHRN/STHC WEST/FWEST
Forced Outages VS. Daily Air Temperature Change
10
Aggregated Values
0
500
1000
1500
2000
<20 20-30 30-40 40-50 >50
MW
s
Daily Min Wind Chill ( � F)
Total Average New Generation Forced Out VS. Daily Min Wind Chill
Winter 2013/2014
0
500
1000
1500
2000
<(-20) (-20)-(-10) (-10)-0)
MW
s
Wind Chill Change from Previous Day (� F)
Total Average New Generation Forced Out VS. Wind Chill Change
Winter 2013/2014
0
500
1000
1500
2000
<(-20) (-20)-(-10) (-10)-0)
MW
s
Air Temp Change from Previous Day ( � F)
Total Average New Generation Forced Out VS. Air Temperature Change
Winter 2013/2014
11
• Comparing air temperature or wind chill changes does not show much correlation
• Daily min wind chill does show an increase in new forced outages as wind chill decreases
Observations
12
• When the wind chill is expected to be below freezing, a minimum of 600 MW of additional online generation capacity should be procured– 1300 MW, when wind chill is expected to be
below 200F• This accounts for the average amount of
new generation forced outages, and is not intended to account for extreme events like Jan 6 or Feb 6
Conclusions