On a Few Things Sewage

The city of Oslo plans to run 200 of its buses on biomethane created from sewage. If this sounds interesting to you, I suggest you check out Rose George's book, The Big Necessity. In one of its chapters, the book goes over a similar use of sewage in China. The Chinese use "digesters" to create biomethane from pig and human excrement. Farmers use the biomethane for cooking and heating, and use the processed manure as fertilizer. Previously the farmers had spread the manure directly onto their crops, spreading disease. During the processing stage, the pathogens are partially broken down and the disease risk is mitigated. Not only does the digester create methane to heat homes, it also creates safer fertilizer for crops. The costs are the one-time construction time and materials of the digester, along with the recurring human cost of running the digester.

Footnote: The biogas link is via /. via EarthFirst via WorldChanging via IWA. Perhaps the blogosphere needs to come up with better linking customs.