Panel output as temperatures increase (texas)

[CrazyRabbit]

i'm seeing about 10% lower production then i did a few months ago! today 98.4 kwh; april 18, 109.5 kwh. inverter temps on south panels over deck are hitting 150 degrees, while west panels inverters are about 130 degrees
also i'm see better production on east panels to what i think is due to lower temperature earlier in the day. also interesting that east west are doing better then south. south over deck is 34 degrees and south over garage is 40 degrees (all other 34 degrees).

 

[MCNE]

I’m in Texas as well seeing about a 9kw drop off of the peek but I’ve only had the system 3 months. 64kw today and 73kw on April 24th. Noting that other things can cause this but read heat plays a huge role.

 

[CrazyRabbit]

i started operating march 28, so about same time as you. 56 q-cell 320 watt panels on iq7+ inverters.. i use to see 295 watt peak per panel, now about 250 watt peak output..
heat is a killer...

 

[wwhitney]

Typical PV panel temperature coefficient of power looks to be approximately -0.5% / degree C, so 10% drop correlates to ~20 degree C temperature delta, or 40F.

Cheers, Wayne

 

[SolarGardener]

i started operating march 28, so about same time as you. 56 q-cell 320 watt panels on iq7+ inverters.. i use to see 295 watt peak per panel, now about 250 watt peak output..
heat is a killer...

I have an almost identical setup in Collin County, but with 365W panels. My peak daily production this week was about 11% lower than my peak production in May.