Texas Grid Operator Expects Capacity Will be Sufficient to Meet Spring Forecasted Peak Demand
March 13, 2023
by Paul Ciampoli
APPA News Director
March 13, 2023
Assuming that the Electric Reliability Council of Texas region experiences typical spring grid conditions, ERCOT anticipates that there will be sufficient installed generating capacity available to serve the system-wide forecasted peak demand for the upcoming spring season, the grid operator said on March 8.
The forecasted April and May peak demands are 59,505 megawatts and 69,921 MW, respectively. These
forecasts are based on average weather conditions at the time of the spring peaks for years 2007
through 2021.
The Seasonal Assessment of Resource Adequacy report does not contain a weather forecast for the spring season. The forecasts also incorporate expected load increases during the peak demand hour due to interconnection of large loads (such as crypto-mining facilities) to transmission service provider networks.
Almost 99,800 MW of spring-rated resource capacity is expected to be available for the spring peak
demand. One thermal generation resource — a coal-fired unit with a 610 MW spring rating — is out of
service for the duration of the spring season. Also, a gas-fired unit with a spring capacity rating of
568 MW has changed its operating period to summer-only.
The total resource amount also includes 844 MW of battery storage capability assumed to be available for dispatch prior to the highest spring net load hours.
This capacity estimate serves as a proxy for the amount expected during a tight reserve hour for the upcoming spring and is an interim availability assumption to be used until a formal capacity contribution method is adopted for future reports, ERCOT noted.
The report also identifies the aggregate amount of installed generation capacity where large loads,
such as crypto-mining facilities, are directly interconnected, and the expected peak reduction in
available generation capacity attributable to these loads during spring hours with the highest risk of
insufficient reserve capacity.
The spring SARA includes a typical thermal generating unit outage assumption of 19,536 MW for
the spring generator maintenance window (March-April) and 15,979 MW at the time of the
forecasted spring peak load in May. These outage assumptions are based on historical outage data
for the last three spring seasons excluding 2021 (2019, 2020, 2022).
Spring 2021 outages were excluded to avoid including Winter Storm Uri-related outages that extended into the spring season.
The spring SARA includes two risk scenarios — base and moderate risk scenarios, and extreme
risk scenarios. The most severe risk scenario assumes a forecasted May peak load with extreme
unplanned thermal plant outages based on historic observations, combined with extreme low wind
power production.