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Solar Panel Questions

This is the place to ask and answer questions about solar panels, how to install and where to find!

Permalink Reply by John MArcellus Hanson on January 8, 2010 at 1:46pm: How much does the efficiency change when a solar panel is wet?; ▶ Reply to This

Permalink Reply by Nick Yecke on January 8, 2010 at 8:18pm: John,

I haven't seen anything that suggests any significant decrease in efficiency from water droplets, since the panels are coated with glass. The light may refract when passing through the droplets, but they may also act as a lens as well. I could see a decrease in efficiency from snow though, because its high reflectivity index would cause more light to reflect back into space (as is the case at the poles) and make it more difficult
for light to penetrate into the panel.

Hope this helps.
- Nick; ▶ Reply to This

Permalink Reply by Bryan Accra on January 8, 2010 at 9:10pm: I'll also add on that solar panels are rated for maximum efficiency on a clear sunny day. If they are wet, it might mean there is cloud cover which will have an effect on the efficiency anyhow. If they're wet and it's sunny, they would probably dry up quickly enough so there would not be any significant effect.; ▶ Reply to This