Photovoltaics on the roof as a second layer

Yes - unfortunately the cells get very warm - which reduces their efficiency (to the annoyance of every photovoltaic system owner).

That is why my highest daily production last year was also on a day in April. (At least I have no other explanation.)

That's why I had my highest daily production on an April day last year. (At least I don't have any other explanation.)

Neither do I.

Example: On the west side, I have a fixed approx. 410 V present, no load, without power. When the modules warm up in the afternoon, it drops to about 360 V.

My forecast also predicts less yield in June than in May. Probably also because the reduction in performance due to heat has the greatest impact.

Me neither.

Example: On the west side I have roughly 410 V fixed present, no load, without power. When the modules get warm in the afternoon, it drops to about 360 V.

My forecast also predicts less yield for June than for May. Probably also because the reduction in performance due to heat has the greatest effect.

Last year, the production in June was overall already higher than in May. July as well. August was, I believe, lower (but it was also crappy weather).

Last year, the June production was already higher overall than in May. July as well. August was, I think, lower (but the weather was a P... too).

I'm curious, honestly. I don't have any real data yet. Last year, the summer here with us: rain shower.

May is already over 150 kWh above the forecast – despite a weak second half.

Today, however, due to the storm, it was like the North Pole here. Yield rounds down to 0. It just started again, 20 watts from the roof, rain, darkness like at 9:15 p.m.

For us, the best photovoltaic day was last year in July with 50.15 kWh. This year it was at the beginning of May (05.05.) with 48.79. We have a pure south-facing system; on these days, the sun was shining fully, meaning it must have gotten quite warm, especially the July day was certainly very warm. However, the heat apparently did not matter much. Much more significant was that on the respective day in May we barely had any consumption around the time when there was particularly high yield. So it was curtailed; otherwise, it would certainly have been more than 48.79 kWh. You can exactly see in the picture how the consumption peaks (green) create yield peaks... with us, there is no curtailment when there is corresponding consumption; therefore, we could use not only 70% but the full 100% yield.

thanks, you have convinced me that [Aufdach] is probably really better, - better ventilation - no sealing problems - more flexibility when replacing the modules - .. regards dieter