Second hand solar, problems and success.
I finally have most of what I need to test my solar hot water system with second hand panels.
My very first problem is, 3 of the 14 panels leak. Two will need to be swapped out with two spares I didnt install for this very reason. The third is a very slow leak that I may be able to fix, but for now I will bypass it.
With 14 panels I expected around 100,000 btu if peak production. With 11 panels, two hours before solar noon, and with the sun still too high in the sky, the system appears to be producing 60,000 btu per hour.
In case anyone is interested. It takes 2:45 minutes to fill a 5 gallon bucket. The water going in is 45⁰, the water coming out is 120⁰.
That is a 75⁰ difference. Multiply that by 40(the weight, in pounds, of 5 gallons of water). That comes out to 3150 btu. It take 2.75 minutes (45 seconds is.75 minutes)
3150btu divided by 2.75 minutes and you get 1145 btu per minute. I round that down to 1000btu/minute to make the math easy, and i would prefer to error on the side of caution.
1000 btu per minute is 60,000btu per hour.
60,000 btu per hour is 17,500 watt hours.