The last total solar eclipse to pass over parts of the US was in 1979. Businesses have become much more reliant on solar power since then and the eclipse on August 21 could affect the 45 gigawatts of solar capacity installed throughout the country.
During the eclipse, it is expected that the moon will completely cover the sun and obscure its rays in the “area of totality.” In areas outside the totality, there will be partial blockage of the sun’s rays. While utilities have had time to prepare and plan to have backups of additional types of energy, meaning that the nation’s power grid is safe, what will the eclipse mean for businesses with their own solar arrays? Businesses will see production on their solar PV systems lowered and solar thermal systems will not heat as much water, the California Independent System Operator reported. California, the state with the most solar power generation, is expected to lose 4,194 megawatts of large-scale solar electricity production.
However, the overall impact of the eclipse on onsite solar arrays will be minimal, according to Jason Slattery, director of solar for GEM Energy of the Rudolph Libbe Group. “Solar responds to different amounts of light over time, so an eclipse will have no more effect than cloud cover, night time or a brownout. The arrays will ramp down in production, but pick up again as soon as the light returns.”
Slattery reiterates that the grid, too, is safe. “There will be minimal impact, if not zero impact, on grid reliability as well. The grid is very resilient,” he says. As a spokesman for North American Electric Reliability Corporation explains, “The grid has built-in redundancies that include a variety of other fuels such as coal, hydro, natural gas, nuclear, and wind.”