Colin Miller wrote: It would appear to be an experimental setup only, although I don't have the book so don't know for sure if he ever went further with it. It's a very small shed, but getting it to 50ºC (125ºF) for 8 months isn't shabby.
I studied scientific experiments on forced aeration of manure. According to the temperature graphs, active blowing with the required amount of air allows the mass to heat up from 10ºC (50ºF) to 60ºC (140ºF) in just two hours. If air treatment continues, then in about 10 to 12 hours, humidity decreases from 75% to 58%, and biochemical reactions stop. I am confident that with additional moisture, thermophilic microbes could produce significantly more heat. Nonetheless, even with this data, calculations show that 1 cubic meter (35 cubic feet) of compost can generate approximately 20 kilowatts of heat over 10 hours. If we consider a pile with a mass of 50 tons (110,000 pounds) and spread the time over 2000 hours (three coldest months), the heat output would be around 5 kilowatts per hour. The size of the house that can be heated with this amount of heat naturally depends on the region.
