Solar panels can still operate in the rain, but their power output depends on cloud coverage. Heavy rain clouds will most likely hinder energy production, but rainfall provides a safe and easy way to clean
solar panels.
Anything that blocks sunlight from
solar panels can reduce their
power production, including clouds,
fog and shade from trees. However,
solar panels can still receive sunlight on cloudy days. Clouds block some of the sun’s rays, but not all of them. A solar panel’s power production on cloudy days depends on the cloud coverage’s thickness.
On a typical cloudy day, a solar panel can typically produce 10 to 25% of its typical power capacity. This percentage can vary based on the solar panel’s efficiency and the cloud coverage level. Solar electricity production can also intensify for brief moments on cloudy days due to the “edge-of-cloud” effect, which occurs when cumulus clouds pass by the sun and their edges magnify sunlight, causing more powerful sunlight beams to reach solar panel surfaces.
Solar panels can produce electricity on cloudy days, but not always on overcast days. If an overcast day occurs,
you can determine whether your system is producing energy by checking for shadows outside. Your system is most likely generating power to some extent if you can see objects casting shadows. The absence of shadows indicates the cloud coverage is too thick for sunlight to reach your solar panels.
Snow can hinder solar energy production more than rain and cloud coverage because it accumulates on panel surfaces and blocks light. However, snow will eventually melt and slide off panels, depending on their tilt and the
weather conditions following a snowstorm.