WASHINGTON, August 9, 2017 - On Aug. 21, a solar eclipse will obscure the sunlight needed to generate electricity at approximately 1,900 utility-scale solar photovoltaic (PV) power plants in the United States. The North American Electric Reliability Corporation (NERC) does not anticipate the eclipse will create reliability issues for the bulk power system. Solar-powered generators centered in the path of totality will be affected the most, as the moon will block all direct sunlight for up to three minutes. These generators will also be affected to a lesser extent throughout the entire eclipse event, which will last for up to three hours, measured from the onset to the ending of any blockage of direct sunlight. During the eclipse, electricity generators in the areas affected by the eclipse will have to increase output from other sources of electricity generation to supplement the decrease in solar power. NERC’s recent 2017 Summer Reliability Assessment does not anticipate any impacts on the reliability of North America’s bulk power system attributable to the eclipse, based on an analysis published in April.