Yes. Solar panels keep producing electricity on cloudy days, just less of it. According to EnergySage, panels on an overcast day typically produce roughly 10 to 25 percent of their normal output, depending on how thick the cloud cover is, so thinner clouds mean a smaller drop. In some cases clouds can even reflect or concentrate sunlight and briefly raise output.
Panels produce no power at night, so homes rely on net metering or batteries after sunset. Cloudy climates can still be strong solar markets: EnergySage notes that foggy San Francisco and rainy Seattle rank among the top U.S. solar markets because high electricity rates make the savings larger.
Source: EnergySage: Do Solar Panels Work at Night or On Cloudy Days?
Image: Solar panels at Heidel Hollow Farm, Pennsylvania, U.S. Department of Agriculture, public domain, via Wikimedia Commons.
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