How often should I clean my solar panels?

In most places, there’s more pollution in the winter, which is why the spring is a good time to do an annual cleaning. Solar panels that are cleaned once and twice a year produce 3.5% and 5.1% more electricity respectively than those that are left uncleaned. 

While cleaning once or twice a year is usually enough, in some places panels require extra attention. A prime example of this is the southwest region of the U.S., where rainfall is limited for several months at a time. There, the accumulation of dirt is far greater. 

Another example is when solar panels are installed near sources of pollution such as freeways, factories and airports. Here, too, they’ll need to be cleaned more often. 

Other special cases to consider include autumn and winter, where the removal of leaves and snow is important for optimal performance.

Also take into account whether or not your panels are installed at an angle. Rainwater has an easier time cleaning solar panels that are tilted, so if your solar panels are mounted flat, you might need to clean them more often. 

Finally, here’s the best piece of advice when it comes to frequency: Monitor changes in the power output of your solar panels before and after cleaning. Experiment with different time intervals. Take note and evaluate what works.