It has been some time since I added a post, and I have more news of the biodigester in the Philippines. The experimental use of other material to charge the biodigester is underway, but has not proved as successful as expected. The whole information will be added tomorrow, but he gist of the matter is that only the potatoes and yams really boosted gas production.
This is surprising, since codigestion is a recognised practice with almost all vegetable rests. Possibly the pieces were slightly large, but that should really just slow the process. It is, however, common practice to pasteurise such material before adding it to a digester, and maybe the vegetables had been treated with an antibacterial agent before being offered for sale. They were simply waste from a large market, so that is a possibility that will have to be investigated. The potatoes and yams did boost production though, but there is no information available for bagasse (the remains after sugar cane has been processed).
Being a waste product, this is a very hopeful avenue for research. Clearly, it will leave a large quantity of fibrous matter which will not be digested, but there should be a quantity of gas to be gained from the material. The fibrous matter left can either be burnt (which is the usual use for bagasse) or composted afterwards. Aerobic bacteria are quite capable of dealing with wood or fibrous matter.