On April 8, 2024, a total solar eclipse briefly but fully obscured sunlight to utility-scale solar electric generation facilities along the eclipse’s path, from Texas through Maine. Texas was especially affected because of how much solar capacity was in the path of totality.
- According to our Hourly Electric Grid Monitor, the Electric Reliability Council of Texas (ERCOT), which is the primary balancing authority in the state, lost approximately 8.9 gigawatts (GW) of solar capacity during the eclipse.
- The ERCOT five-minute generation data show solar generation fell starting at 12:20 p.m. central time (CT). The eclipse ended in Texas at 3:07 p.m. CT.
- Like the rest of the country, natural gas-fired generation largely offset the lost solar generation in ERCOT, replacing approximately 80% of the lost solar on April 8. According to EIA’s Hourly Electric Grid Monitor, which measures the grid response over a broader time interval than the data pulled directly from ERCOT, natural gas-fired power plants generated an additional 6.2 GW on April 8 between 1 p.m. CT and 2 p.m. CT, the hour when totality took place, to replace the lost solar generation. Coal and other sources—mostly battery storage—each produced an additional 0.8 GW to offset the loss.
- In Texas, solar generation is often the second-leading energy source in ERCOT during the time of day the eclipse crossed the state behind natural gas.
- In ERCOT, throughout the day, Texas saw less solar generation on April 8 than on April 7, with cloud cover that persisted through April 9.
Principal contributors: Lori Aniti, Glenn McGrath, Kimberly Peterson