Solar Panel Infrared Filters

we want to do a solar panel that has a filter that blocks infrared radiation. coming that this creates heat and heat reduces the efficiency of solar panels. what material would you suggest we use as filter? and if there's any suggestion you can give I would be really grateful.
- eugenio mickael romillo (age 21)
manila philippines

This sounds like a good idea. There are all sorts of infrared-absorbing glasses and coatings. We don't have the expertise to advise you on which is best. Here's some suggestions:

1. Check the sensitivity of your panels to different wavelengths. It may be that the red end of the visible isn't particularly useful. You should match your filter to the sensitivity of the panels, so that it starts filtering well just in the wavelength range where the sensitivity becomes very small.

2. Be sure to have anti-reflective coating. Otherwise you might lose more by reflection than you gain by keeping out the heat.

3. Your filter will get hot. If it cools mainly by radiation, about half the incoming energy that it catches will still go to the solar panel. You could check whether the energy cost of running a cooling fan would exceed the energy gained by keeping the panels a little cooler.

Mike W.

(published on 08/22/2013)