I've been wondering if it'd be viable to seal the top, somehow, and capture the methane product.
In the Jean Pain system, he had a large tank in the center of his piles that was filled with water and a bit of the compost mix. (the water heating pipes were wrapped around the tank in his system, which had even more mass than this system in this thread that we are on. A pipe out of that tank gave off methane gas out the top, and this was stored in old inner tubes. He used some gas to fire a compressor to pressurize the gas into tanks, and from there used it to cook on, as well as to power the chipper shredder, and his trucks. I can't see a reason why you couldn't seal the top of the system, so long as you had some air intake as well, to provide oxygen to the bacteria.
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