Renewables: "talking 'bout my generation"

Netexporter · 25 May at 10:15AM

https://forums.moneysavingexpert.com/discussion/comment/82010802#Comment_82010802

If it wasn't so hot I might have taken my thermal imaging camera up on the roof to have a look. 28 degrees at 10:00; what sorcery is this!

Netexporter · 25 May at 2:56PM

In the interests of science I've been up on the roof and can report that my panels are at about 48 degrees. Air temperature is about 32 degrees. The roof tiles are a lot hotter at 65 degrees.

NedS · 25 May at 3:15PM

https://forums.moneysavingexpert.com/discussion/comment/82011250#Comment_82011250

Interesting, and thank you for climbing up on the roof! That would only account for around 7% thermal degradation on newer panels and maybe 12% on older less efficient panels. I was expecting a higher panel surface temperature, closer to that of your roof tile temperature.

Could it be an inaccuracy/inconsistency of the thermal imaging camera when measuring the two different surfaces (glass vs tile)?

Less scientific, but are you able to feel a noticeable difference with your hand between the two surfaces? I have some old roof tiles to hand, but not an old solar panel that I could put out in the garden to compare.

Netexporter · 25 May at 3:59PM

Yes, I did the hand test. The tiles were considerably hotter, so I'm reasonably optimistic the camera wasn't lying in this case.

I also clamped an electronic pipe thermometer onto the edge of the panels. The aluminium was in the upper 30s. I also managed to get the sensor onto the edge of the glass, which showed a higher temperature, in the lower 40s. However, as the collector surface is concave, to make maximum contact on pipes, I wouldn't set much store on the accuracy.