need feedback on a heating idea

[molly]

My sister's friend who is incarcerated (which is another story) and
needless to say has some time on his hands, came up with this idea. I
saw it in a letter so I'll describe the picture. There is a compost
pile with an upright spiral copper tube in the middle of it, the
copper tube runs out the bottom, and into (welded?) an old car
radiator. Then he had a car battery, which is charged by a small
solar panel, that runs a fan, which blows on the radiator, and out
into the hoop house. He was figuring a compost heap can get to 150
degrees in the middle. Can you picture this?

One thing that might be a problem is getting at the compost when you
need to use it, but it seems you could design something around that.

What do you think?

[Nilgün Tuna]

The compost pile will radiate the heat on its own. Since heat rises, It will
fill the hoophouse regardless. No need for high tech. There have been
several posts about how Growing Power, Will Allen's organization, usues
compost piles for heat, piling it up in corners of the hoop house or
greenhouse as well as piling it outside along the edges of the structure.
Then it is incorporated into the growing medium.

Another suggestion from and old Eliot Colemanbook was to use fres manutre as
a heat source in coldframes by burying a foot of it under the soil or simply
putting pots on top of it. A good way to use ALL your resources!