Solar in the Fall

Now that cooler weather has officially set in here in Massachusetts, you may be wondering – what happens to my solar panels in the fall? Do they produce solar energy? Or maybe you are looking to install a solar panel system, but you are not sure if it worth it to install at this point in the year. Well, don’t worry, because solar panels produce energy as long as the sun is out, no matter the season!


Many people believe hot and sunny summer days are prime solar energy producing conditions. However, cool weather can actually be better for solar panels, as most electronics do not fare very well in the heat. Heat actually reduces solar panel output, because of thermodynamics laws. Essentially, solar panels produce energy by absorbing photons of light to excite the electrons in a solar cell. This is how voltage is created. But, when it is hot out, solar panels are hotter, so more electrons are already excited. This means that photons can’t excite as many electrons, so less voltage is produced. So, the efficiency of the panels is reduced in the heat.

In general, solar panels are most efficient between 59 degrees and 95 degrees Fahrenheit. Keep in mind that this is the temperature of the physical panel, not the air temperature. Since panels are dark in color, they often heat up and are a few degrees hotter than the air temperature on a given day. So, the cooler fall temperatures can actually be great for solar panel efficiency!


Although days are getting shorter, September and October receive a respective of 237 and 207 hours of sunlight per month! As mentioned above, solar panels produce energy from the sunlight, not from the heat. And it is certainly still sunny out in the fall!

Should I wait to install solar panels?

If you are unsure whether to install solar this fall or wait until next summer, just think of all those hours of sunlight that you would be missing out on. And that is just for two months! Additionally, keep in mind that the federal solar tax credit is reducing again in 2023 from 26% to 22%, so don’t wait too long! If you are considering going solar, contact us today.