AP Photo/Lalo R. Villar
DCL
Until people stop eating meat and drinking milk, we will continue to have a lot of manure on our hands. Environmentally speaking, that's been a real problem, so it's about time that manure is turned into a resource rather than a waste we don't know what to do with. And it's starting
Basically, it goes like this: manure collected by sewage pipes that run under a barn is mixed with other food wastes and then heated in an anaerobic digester, where it is kept for five days. During that time, microbes are busy decomposing the manure, a process that produces methane gas which bubbles to the top and then runs into a diesel generator, where it is burned to produce electricity. Often, the liquids that are left over are used as fertilizer, and solids are processed to be used as bedding for the cows. (If you don't think that sounds nice, maybe think twice before ordering your next burger.)
Using manure for biogas puts a dent not only in our dependence on fossil fuels, but in our waste stream and greenhouse gas emissions as well
