Critical periods of risk for peak electricity demand in Texas have shifted to later in the evening because of rapidly growing additions of solar resources, according to the Electric Reliability Council of Texas (ERCOT).
Dispatchable generation growth has been nominal while increased solar resources have pushed the critical risk periods to between 8-9pm, when solar generation falls, according to ERCOT vice president of planning and weatherization Woody Rickerson. He made his comments during a talk by the Gulf Coast Power Association.
Dispatchable generation — electricity generation able to come with short notice from grid operators — can make up for periods when wind and solar output is not available, but that flexibility has diminished in Texas.
"We're going to have to rely more on wind and solar this year than ever before," Rickerson said, mirroring comments about grid adequacy issues made by ERCOT's chief executive earlier this year.
ERCOT expects peak demand in the 2023 summer season at 83,412MW according to its latest Seasonal Assessment of Resource Adequacy (SARA). Peak demand in the 2022 summer was 80,148MW, an all-time record for ERCOT.
"The answer to this is more batteries, [and] more thermal generation," Rickerson said, referring to power plants that use natural gas, coal or other combustion fuels. Thermal power supply growth has not kept up with demand generated by a growing Texas population.
More than 1,400 requests for new generators were made between April 2022 and April 2023, compared with 600 requests three years ago. Those 1,400 requests would create an additional 265GW of electricity generation: 130GW of solar generation, 22GW of wind, 100GW of battery storage and 13GW of gas-fired generation.
