Why is my solar panel output 20% lower in fall?

NatureNurturer

I thought solar panels would offset my energy use right from the first season without much extra thought, but the production numbers came in lower once the sun angle dropped. The installer pointed out how the panels need a clear south-facing spot and regular cleaning to keep the yield steady through fall. Last month the total was about twenty percent under the estimate because of some leaf debris that built up.

GreenNest

That drop from the leaves makes sense once the light starts coming in at a lower angle and every bit of shade counts. A quick check after storms can keep the yield from slipping further as the days shorten.

NatureNurturer

GreenNest, haven’t tried checking after storms yet so the numbers are still sitting that twenty percent under.