Drop in solar panel energy production

[Gina]

I noticed that my energy production mysteriously dropped by 20% last month.

Does this mean I have to replace the entire system?

[Alan]

Do you have a lot of shading or dirt covering the panels? That may be causing mismatch, bringing down your energy production, especially if you don’t have microinverters.

[Gina]

How much is “a lot? Here is a picture of what I'm dealing with:

[Alan]

Oh, that is a lot....

Easy solution: Clean off the solar panels with water. A simple spray of water from a garden hose will do.