cooling PV-panels

As you all know, the output of solar panels decreases with rising
temperature. (about 0,5% per °C)

So, it might be interesting to cool panels at high solar intensities. Maybe
just during a few hours a day in summer.

For example by trickling water over the panels.

When the water is in an open circulating system, evaporation of the water
will keep the temperature down.

Ofcourse evaporation of water will increase the percentage of salts etc., so
a small amount off the circulating water should be refreshed continuously
(by clean water ofcourse: stored rainwater?). Like in the blowdown system of
a steamgenerator.

Has anyone in this group ever experimented with this, or has knowledge about
experiments and results?

Best regards,
Jan

 

It's nice to use the heat vs merely evaporating water. When I put an inch of
water in a polyethylene bag on top of a PV panel, the output only dropped 6%.
(I didn't wait for a temperature change.) This might work well with a mirror
reflector to put 2-3 suns onto a standard horizontal PV panel.

Nick

 

Use a water filled sunlight filter and draw off the warmed water.

Graham