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- Jan 22, 2004
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I know some people have done/tried similar. I haven't been able to dig up a link though. Sorry!
I found a table that shows the thermal conductivity of various materials. Concrete actually conducts heat a little bit better than "earth, dry", but it's hard to say whether either one is a really bad conductor of heat, or a really bad insulator. The truth is, without knowing the equations and running the numbers (like a real engineer could) I can't say how well such a system would work (despite the fact that I already said "it won't work"). Heat will leak through the PVC, and into the earth at some rate, call it RL (loss). Your tank will produce heat at another rate, call it RG (gain). After the dirt warms up to a stable temperature, if RL is > RG, then it will work great. RL increases as the length of the buried pipe increases, so if you buried enough pipe, it certainly would work (assuming the sun doesn't keep the dirt warmer than your tank water). I'm guessing that you would need to bury so much pipe that it wouldn't be practical, but again, I'm guessing. Maybe I'll look up the equations and do this right some time, just to make sure I'm not giving bad advice.snowmaker;160708 said:My guess - but the concrete (thermal mass) may not dissipate heat as well as plain old earth. I thing it will hold heat - like when you heat a concrete slab or 2nd story floor.
CaptFish;160717 said:I don't think you want the hard board insulation, it may hold the heat in. I would cover it with good old grass.
Gross 21434.00
Net with all credits Fed State etc 8852.00
Annual Income from system, Minimum 1200.00 Maximum 2400.00 a year they auction your generated power to Utilities this is for 10 years so 12k to 24k back in our pockets over that time frame.
Electricity produced 4100kwh a year at .18 cents is 738.00 a year.