And if so, how much heat is produced? Ok, so here's the problem. We are working with a generator salesman who is trying to sell a bunch of generators to a sewage treatment plant to capture the waste methane and burn it to make electricity. Great idea. The complication is that currently *some* of the methane produced is used to fire boilers to heat the crap to its optimal temperature of 95F for digestion. And we don't know how much gas is currently used for that, so we don't know if we can completely eliminate it (we will recover some of the waste heat from the generators for that purpose, but the efficiency is low). We're also considering insulating the digester tanks (outdoor concrete tanks 175 feet in diameter) to reduce the need for heating them, but if we insulate them and they produce heat, we'll kill the bacteria. We have numbers for the methane that is currently being burned-off and for the gas being produced, but they don't match: they are often burning as waste (not in the boilers) more than they produce. This could be because the production numbers are methane only and the burning (flaring) is methane + carbon dioxide, but we don't know those proportions either. I know aerobic digestion produces heat, but I don't know about anaerobic. Anyone have any insights...?