Electric grids across the U.S. are bracing for a significant decline in solar generation during Monday’s total solar eclipse, which will span multiple states. NASA estimates the path of totality, when the sun is fully blocked by the moon, to last from 1:30 pm CDT to 2:35 pm CDT in the U.S. Here’s how the eclipse is expected to affect grid operators across the country:
ERCOT in Texas forecasts a dip in solar power generation to roughly 8% of its maximum output during the eclipse, with solar generation dropping from over 10,000 MW to about 1300 MW over two hours.
MISO, covering parts of the Midwest, South, and West, anticipates a reduction of 4,000 MW of solar capacity over 90 minutes, followed by a 3,000 MW rebound, posing challenges in ramping and congestion management.
ISO New England estimates a potential 92% loss of overall solar generation, with solar power being replaced by other resources such as batteries, pumped storage, or natural gas to meet demand.
NYISO in New York expects to generate 3,500 MW of solar production at the eclipse’s start, dropping to 300 MW over an hour before rising to about 2,000 MW afterward, requiring additional resources to account for the loss.
PJM, covering parts of the Northeast, Midwest, and South, prepares for a temporary reduction of at least 85% to 100% of production from its solar fleet, with plans to defer maintenance and keep hydropower resources on standby.
CAISO in California forecasts a drop in grid-scale solar generation by 6,349 MW to 7,123 MW in nearly one and a half hours, planning to ensure sufficient natural gas and hydropower resources and potentially restricting routine maintenance.
As the eclipse sweeps across the U.S., electric grid operators are implementing strategies to manage the impact and ensure grid reliability amid the temporary decline in solar generation.
