The especially hot Texas weather has consistently stressed the power grid this summer.
The Electricity Reliability Council of Texas (ERCOT) has set 10 new all-time peak demand records this summer. ERCOT set an all-time peak demand record of 85,464 MW Aug. 10.
The organization has relied more on renewable energy this summer than it has ever had to, specifically solar and wind energy. While solar energy is helpful because it is the most effective when the sun is the hottest, it can be unpredictable.
When the sun lowers, solar energy’s contribution to the generating capacity dips, which explains why the grid has been the tightest during the evenings. The majority of ERCOT’s conservation appeals so far this summer circle the hours of 3 to 9 p.m.
That’s why next month’s solar eclipse presents a unique problem for the Texas grid.
An annular solar eclipse will pass through the state Oct. 13. While the eclipse should be partially visible throughout the entire country, it will directly go above Odessa, then San Antonio and Corpus Christi.
The eclipse will impact photovoltaic generation resources (PVGR) in ERCOT, which essentially refers to the conversion of light into electricity.
PVGRs will experience a maximum coverage of sun ranging from 76% to 90% between 10:15 a.m. and 1:40 p.m., ERCOT officials said.
Solar energy intake will be hit the hardest at 11:50 a.m. that day, where the system’s “clear sky capacity” will be reduced to a minimum of 13%.
Although weather conditions expect to be noticeably cooler next month when the eclipse hits than compared to the summer, the sudden loss of solar energy production resembles the evening conditions that have forced ERCOT to call for power conservation multiple times this summer.
Nevertheless, ERCOT officials say the energy organization is preparing for the eclipse and will use available tools to balance the system.
ERCOT said it is working with solar forecast vendors to ensure the forecasting models account for the impact of the eclipse.
Additionally, it will prepare the system as necessary to meet both the down and up solar ramps the day will bring.
The organization will also use ancillary services, which are additional tools ERCOT uses to manage uncertainty and variability on the grid. They are purchased by ERCOT in the day-ahead market to balance the next day’s supply and demand of electricity.
ERCOT is responsible for 90% of the state’s electricity service.
