[seafarer]

One summer during college, I worked in the lab of our local sewage treatment plant. They use anaerobic digestion for tertiary treatment of the sludge - and they use the methane produced to heat the whole plant, and keep the digesters at optimal temperature in the winter (this was southeastern Ontario).

There was a news story a few weeks back about Pacific Gas & Electric and BioEnergy Solutions working with California dairy farmers to use methane from their herds' manure to feed into the natural gas pipeline distribution system. They are using controlled bacterial digestion of the manure on the farm to produce the gas and render the sludge for agricultural disposal (technically does not rate as a fertilizer, but as a soil conditioner). This process also avoids groundwater contamination from manure pile runoff. BioEnergy Solutions plans to provide 3 billion cubic feet of gas a year to PG&E (supposedly enough to meet the needs of 50,000 homes).

Some people are thinking truly creatively about energy.