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Solar Yield vs Temperature.
The recent hot spell has taken its’ toll on energy production; though the spec. sheet for a solar panel may well show the percentage loss against elevated temperatures, it really comes home when the sort of temperatures we have been experiencing this last week or so occur. Our 8.1 kWp. array will often produce ~6.4 kW for the core times at this time of year (as indeed it has been doing today with external temperatures in the low 20’s C.). When the sun shines in a clear blue sky but the temperature is hovering at ~ 30 degrees or so C., then the highest output drops to ~ 5.2 kW during those same core hours. Admittedly ten of our 21 panels are ground mounted in the garden and I suspect don’t feel so much breeze as those on the various roofs and thus warm all the more. Should I send a request to the Met Office for full sun from 05:00 - 20:00 but with a cap on the temperature of perhaps 24 degrees C?😉 Regards, Toodles.
Toodles, heats his home with cold draughts and cooks food with magnets.
A sprinkler may be your best friend, assuming you are far away from the new Kent desert! 😁
8kW Solis S6-EH1P8K-L-PLUS hybrid inverter; G99: 8kW export; 16kWh Seplos Fogstar battery; Ohme Home Pro EV charger; Vaillant Arotherm Pro 7kW; 100Amp head, HA lab on mini PC
Posted by: @toodles@batpred How good are panels at withstanding thermal shock I wonder?
Thermal shock brings back memories of holding the driving wheel while driving back from the Algarvian beaches… 🔥
Nothing remotely close to that experience near that Kent desert.. 😉
8kW Solis S6-EH1P8K-L-PLUS hybrid inverter; G99: 8kW export; 16kWh Seplos Fogstar battery; Ohme Home Pro EV charger; Vaillant Arotherm Pro 7kW; 100Amp head, HA lab on mini PC
I noticed similar during the hot weather.
My south facing 7.2kWp array topped out at around 6.1kW during the very hot weather suggesting ~15% thermal degradation. My panels have a rated thermal coefficient of around 0.3-0.35% per degC above 25C surface temperature, suggesting the panel surface temp maybe as high as 70C (or maybe 60C assuming I have other losses)
Samsung 12kW gen6 ASHP with 50L volumiser and large radiators. 7.2kWp solar (south facing), Tesla PW3 (13.5kW). Net Zero
8kW Solis S6-EH1P8K-L-PLUS hybrid inverter; G99: 8kW export; 16kWh Seplos Fogstar battery; Ohme Home Pro EV charger; Vaillant Arotherm Pro 7kW; 100Amp head, HA lab on mini PC
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