Snow on Solar Panels

Qyburn

Earlier this morning I noticed our panels were still covered in snow, after it had melted off the surrounding roof. I don't know why that would be. But the surprise was seeing that even in that state they were still whacking out 2kW when the sun was out.

QrizB

I usually get the opposite; the snow melts from my solar panels (& slides off) before it melts on the rest of the roof.

What's the nominal output of your array? 2kW is what fraction of that?

Qyburn

QrizB said:

What's the nominal output of your array? 2kW is what fraction of that?

Twenty panels, something over 8kWp

QrizB

Qyburn said:

QrizB said:

What's the nominal output of your array? 2kW is what fraction of that?

Twenty panels, something over 8kWp

So ~25% of nominal? That's still a good figure, given the coverage.

Qyburn

QrizB said:

Twenty panels, something over 8kWp

So ~25% of nominal? That's still a good figure, given the coverage.

Looking back a couple of days, full sun at 10:00 would be round about 4kW.

Martyn1981

QrizB said:

Qyburn said:

QrizB said:

What's the nominal output of your array? 2kW is what fraction of that?

Twenty panels, something over 8kWp

So ~25% of nominal? That's still a good figure, given the coverage.

Especially given what looks like a very shallow pitch (20d ?), which is more a summer specialist. Looks like the sun was hitting the top row, and starting to melt it.

I've has pretty good generation (years ago) through about 100mm of snow. But it was fresh and fluffy, so quite transparent.

Qyburn

Martyn1981 said:

Especially given what looks like a very shallow pitch (20d ?), which is more a summer specialist. Looks like the sun was hitting the top row, and starting to melt it.

Correct, 18° pitch, facing 191°. So quite an oblique angle compared to the sun at 25° and 144°.