This past Sunday the Chicagoland Permaculture Meetup and Living Off The Grid Meetup joined forces to build a compost pile that would provide heat for the grow beds of a greenhouse.
First we cleared away the remains of last years compost pile, pulling out the hose to reuse in the new pile and spreading the compost on the garden.
Then we measured out a radius of 7′ and began depositing the wood chips and horse manure, all the while embedding nearly 300′ of pipe spiraling throughout, and a 55 gallon container in the middle to produce methane (that’s a whole other story).
We added many gallons of water with each layer to provide moisture for the bacteria that will break down the pile and generate heat.
The resulting pile was nearly 5′ in height, you can see the layers of wood chips and manure within.
Once the pile begins to heat up, a pump will move the heated water into a yet to be built hoop house, heating grow beds inside, and will keep the temperature nice and warm for starting seeds.
If you’re interested in more information, you can see the original inspiration for this project on YouTube: Jean Pain part 1 & part 2. Jean Pain extracted hot water from his 18′ diameter, 9ft high pile for 18 months. In the picture below you can see Jean, his methane storage tubes in foreground and the compost pile in the background. Peter Bane of the Permaculture Activist has also written a great article on Jean.
Another example is of Darren Doherty using a similar idea to make a compost heated shower.