Correction: ERCOT inadvertently counted three new gas units twice due to a change in operational status, which changed reserve margins slightly. The corrected numbers are reflected in the article.
The Electric Reliability Council of Texas (ERCOT) said it expects adequate electricity resources to meet this summer’s highest electricity usage in the ERCOT region, according to the summer assessment. It also said four thermal units totaling 3,280 MW, which were previously planned for completion between 2014 and 2016, have been delayed a year.
“We expect to have enough generation resources to exceed peak demand by 17.5 percent this summer, surpassing the 13.75 percent threshold set by ERCOT for reliable operation of the electric grid in case of major outages or unusual temperature extremes,” said Kent Saathoff, vice president of grid operations and system planning.
The summer peak demand forecast is 63,898 MW, almost 2,000 MW less than last summer’s record-breaking peak demand of 65,776 MW on Aug. 23.
Reserve margins are forecast to remain above the minimum target through 2013, an increase of almost 2 percentage points since the last assessment, which showed the reserve margin dropping below the minimum beginning in 2013.
“Our reserve margins for the next several years have improved due to the addition of more than 1,000 MW of additional generation,” Saathoff said.
Additional new and refurbished resources added since the December reserve margin forecast include:
•565 MW from three new gas units in Jack County (operational before winter peak);
•406 MW from Greens Bayou 5, a 1973 gas unit in Harris County returning to service;
•45 MW from Lufkin Biomass, Angelina County, scheduled to be available in time for summer peak.
ERCOT’s assessment for 2011 also includes 1,484 MW of contractually committed demand response resources and emergency interruptible loads which operators can dispatch on command.
Another 128 MW in demand reduction is anticipated this summer due to energy efficiency programs.
The summer assessment also shows the reserve margins through 10 years, instead of five. The reserve margin drops below the target minimum of 13.75 percent beginning in 2014 and stays below that level, based on currently committed generation.
Four thermal (fossil-fuel) units totaling 3,280 MW which were previously planned for completion 2014-2016 have been delayed a year:
•1,380 MW, Pondera King Power Project, Harris County, natural gas, June 2014 to June 2015
•620 MW, Las Brisas Energy Center Phase 1, Nueces County, petroleum coke, July 2015 to October 2015
•620 MW, Las Brisas Energy Center Phase 2, Nueces County, petroleum coke, July 2016 to October 2016
•660 MW, Coleto Creek Unit 2, Goliad County, coal, January 2016 to January 2017.
Potential resources not added in the report’s operational generation include more than approximately 2,300 MW of generation capacity which is currently mothballed but could be brought back into service at the owners’ decision.
Summer generation by fuel type is 64.2 percent natural gas, 26 percent coal, 7 percent nuclear, 1.1 percent wind, and 0.7 percent hydro, 0.1 percent biomass and 0.8 percent other (includes landfill gas and petroleum coke and other fuels not specifically categorized such as diesel).
Long-term projections in the annual assessment show three scenarios based on generation retirements at 30 years, 40 years and 50 years. The mid-range scenario of unit retirements at 40 years or older indicates a need for more than 62,000 MW of new generation capacity needed to meet the 2031 projected demand of approximately 99,900 MW (including a 13.75 percent reserve margin).
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