Production in complete shadow...

[sorka]

Yesterday, during my "system test", about 10 minutes before sunset I was still showing 200 watts of production. The panels had long been in complete shadow from the trees. There was no reflected sunlight either. This was entirely ambient light from the sky. No clouds either to reflect sunlight.

This is with a 24 panel G6+ system.

 

[BrettS]

That sounds about right. The panels can pick up a small amount of ambient light like that, but it really doesn’t produce a lot of power. If they sustained that 200 watts for an entire hour that would only amount to .2kWh. It’s just a drop in the bucket of your entire daily production.

 

[sorka]

I was still surprised to see anything. That's only 8 something watts per panel (more if you count before conversion and the power to run the optimizers).

 

[zƬesla]

I've been amazed that my panels (without optimizers or micro-inverters) have produced on full cloudy/rainy days; granted not much

 

[jboy210]

I've been amazed that my panels (without optimizers or micro-inverters) have produced on full cloudy/rainy days; granted not much

Because of the cloud edge effect, the highest reading I have seen occurred on a day with off and on rain clouds.

 

[zƬesla]

Because of the cloud edge effect, the highest reading I have seen occurred on a day with off and on rain clouds.

Likewise, although I was referring to days with no sun whatsoever, full clouds/rain, which unfortunately have been far too many for us this month.

 

[jboy210]

Likewise, although I was referring to days with no sun whatsoever, full clouds/rain, which unfortunately have been far too many for us this month.

Got it. But, unless is really dark you still get some power even when it is cloudy. This article points out that 10-25% of sunny day output is the range for cloudy days. Not great, but better than nothing.

My experience has been that shading is much worse than most cloudy days.

 

[zƬesla]

My experience has been that shading is much worse than most cloudy days.

Yes! We have morning tree shade probably October-March which kills our production much more than a cloudy or partly-sunny day.

 

[jboy210]

Yes! We have morning tree shade probably October-March which kills our production much more than a cloudy or partly-sunny day.

Shading sucks. We are down to 7 kWh/day because of it. Can't wait until the leaves on the big oak causing the shading drops.

 

[zƬesla]

Shading sucks. We are down to 7 kWh/day because of it. Can't wait until the leaves on the big oak causing the shading drops.

We are mostly white pines, so not much needle shedding. Just have to wait until spring. We've gone from peaks of >100/day down to 60, and have averaged < 30 over the past week which has been mostly rainy/cloudy.