ECHOcommunity Conversations

Unique inputs in a biodigester

We maintain two biodigesters here at ECHO’s Global Farm in Florida. Each system outputs biogas for cooking and a liquid digestate for fertilizer. One system is fed with cow manure. The other uses kitchen scraps. Sufficient water is also added. These feedstocks are very common and known to work well. I’m curious to know of less traditional feedstocks that have worked well. Other forms of manure? Majority vegetation? Others?

Hi Will, I worked on energy with some coffee co-ops in Honduras this spring and they reported some folks had tried to bio-digest coffee pulp and waste water from the process but the pH was evidently too low for success. At least that was the report.

Thanks for sharing, Larry. Interesting!

Does anyone have any experience using solely chicken manure? I know it has been done, but have heard special considerations need to be taken for the high ammonia levels in the waste (I wonder if this is more of a pH issue too?).

Hi folks - this is Kate in Cuba

Biogesters - mainly using pig manure - solves a huge problem of this waster (1pig = 10 people). Some of the very big farms (4000 pigs), are not only using the gas for cooking feed, but also for cooking, lighting etc in the homes, and generating electricity into the national grid.

There is heavy promotion of biogesters, and many of the large co-ops are runing several. Individuals are also participating. One I know has her biogester connected to her neighbours pig pen. The abono then is used eventually in my friends organic vegetable garden. There is a special institute which deals with promotion and adaption of technologies, principally solar but also the biogesters.