Believe it or not, the clouds don't stop the solar array from making electricity. This a common misconception that many people have about solar energy. Many detractors of solar power like to wax on about how cloudy days mean no electricity. As usual, they don't know what they are talking about.
Think about it this way: On a cloudy day, is it dark like it would be at 2am? No, it isn't. Why not? Because the Sun's rays still penetrate the clouds. Even the most menacing storm clouds don't make it so dark that you can't see. So, the fact that there is enough light to allow you to see when it's cloudy means the Sun's rays are still hitting the Earth, and any solar panels positioned to catch them. (Do I sound like a Public Service Announcement?)
It is even possible, under the right conditions, to produce more electricity on a partly cloudy day than on a hot sunny day. PV panels can get too hot from all that sunshine and sometimes part of the array will shutdown so the panels can cool down. Cloud cover keeps the temperature low, which can keep more panels cooler during the day, thus allowing them to operate longer. All that can mean more energy produced!
(The heads of anti-solar people everywhere just exploded. Because I'm sure they all read this blog, right?)
So, on cloudy days, photovoltaics keep right on converting sunlight into energy. That means when it's cloudy, you can still charge your computer, wash your kids dirty clothes in the washing machine, go for a walk without a flashlight or turn the tv on so you can watch the Stanley Cup Playoffs. You know, all the important things in life.
The more you know...
