Sure they’re methane producers of the highest order, but at least some of what comes out of cows is being put to good use. Take the Greenhill Dairyfarm Biogas Plant in the United Kingdom. The combined heat and power company Alfagy says a project it worked on there is using the waste from 600 cows, along with other organic matter, to fuel a 430-kilowatt power plant.
Alfagy says this anaerobic digestion plant, outside the tiny village of Ardstraw, Northern Ireland, is unusually efficient: “Normally, central power plants pump more than 50 percent of the energy into the air while turbines waste 75 percent of the wind’s energy. Run on muck, the cow power plant has an energy efficiency of 86 percent, wasting only 14 percent, which a huge step toward a sustainable Northern Ireland.”
