Efficiency Of Solar Panels Vs Temperature

It may seem counter intuitive but solar panel efficiency is affected negatively by temperature increases.

Efficiency of solar panels vs temperature.

As the temperature of the solar panel increases its output current increases exponentially while the voltage output is reduced linearly. If the surface temperature of your roof increases to 30 c 86 f your solar panel s efficiency will fall to 16 7 percent. A field experiment in the united kingdom revealed a drop of 1 1 of. For silicon e g0 is 1 2 and using γ as 3 gives a reduction in the open circuit voltage of about 2 2 mv c.

If you have solar panels with an efficiency rating of 17 percent and a temperature coefficient of 0 45 they will lose 0 45 of their efficiency for every degree above 25 c. The energy production efficiency of solar panels drops when the panel reaches hot temperatures. The temperature coefficient tells us the rate of how much will solar panel efficiency drop when the temperature will rise by one degree celsius 33 8 f. For example sunpower s solar panels all have a temperature coefficient of 0 37 c.

Most solar panels have a temperature coefficient of around 0 3 c to 0 5 c. The effect of high temperatures. For example the peimar 270w panels have a pmax temperature coefficient of 0 43 c. Lost energy 20 x 0 43 8 6 100 8 6 x 270w 91 4 x 270w 246 78w.

If these solar panels heat up to 45 c 113 f that means they are 20 c above the stc temperature. Solar panels are tested for their efficiency at 25 c and that is why this is used as the reference point.