Should you bother cleaning the snow off your solar panels? The surprising answer is… no! A 2015 study in Alberta used the following configuration to test the effects of snow on solar panel performance. There were two arrays of solar panels. One array was consistently cleared of snow while the other went untouched.
For solar panels angled at 45 degrees, the difference in energy production between panels that are cleared of snow and panels that were not was only 1.92% on an annual basis. The largest difference in energy production were panels angled at 18 degrees. In this case, the panels which had snow removed produced 5.25% more energy on an annual basis.
Why is the difference so small? There are a couple of reasons:
- The majority of energy production from solar panels occur in the summer months due to the longer days and the angle of the sun.
- Snow melts off solar panels quite easily when it’s sunny.
If we only take the winter months into account, there can be up to a 20% difference in energy production between solar panels that are cleared of snow and those that are not. Due to the small annual differences in energy production, Solar Consultant recommends that residential customers do not clean their solar panels in the winter.
In some cases, the home owner has to clear the snow off the panels because it is their only source of electricity. However, the majority of residential installations are “on-grid” systems. This means that the house can still draw electricity from the local utility grid if the solar panels are not producing enough power.
Click here to read the full report from NAIT: Go to Report