Overpaneling generic questions


Solar Addict
Apr 28, 2021
Ok, on a more serious note. Over-paneling or exceeding the specifications of your system to try and offset weak production during cloudy days is a bad thing unless your SCC can handle the normal power input when things DO clear up.

It has to do with edge-of-cloud effects. When the sun refracts off the edge of clouds, your panels can actually put out more than their rated output due to lensing. That's why most SCC's have an overload spec, so you don't want to cut it too close when you choose a controller. Nor constantly run your system based on an SCC temporary overload spec as part of your calculations in normal conditions. You need some headroom to account for edge-of-cloud.

Over-paneling is just as bad as over-battery'ing. :) That was 1970's thought. If you can't properly size your batteries according to your load and ability to recharge, just buy over-capacity, and let them get abused. The degradation will seem slower when over-capacity - but we're talking lead acid and sulfation.

I'm just saying - if we dig too far into the mainstream boutique all-in-ones, it is much like a more expensive way of fretting over what jump-starter is properly engineered when you pick one at the auto-parts store.


Solar Enthusiast
Nov 4, 2019
Well I'm very happy have too many panels. Although I probably won't be running AC in Cabo San Lucas from November to March...I'll still be running pool pumps, etc. No way I'll be maxing my inverter or charge controllers out during winter solstice.