5 Ways to Make Energy With Excrement
photo by Matthew Chatfield
Perhaps its because of our monkey roots—their lack of inhibition when it comes to handling their own filth must be lurking in us somewhere—that many of us find poo jokes and toilet humor so funny even as we, cough, mature. While excrement may elicit laughs, snickers and giggles from some, it really is serious business when it comes to energy.
For those that don't know, the way all of these projects work is they take the human or animal waste and convert it into biogas via anaerobic digestion. Then the gas is either fed into the exisiting natural gas distribution system, converted into electricity, or used directly as an energy source.
It seems like we’ve heard about enough new human or animal waste to energy projects or studies lately that a roundup seems in order. From the past seven months, in reverse order:
At a cost of $1.1 million the Lions Gate Wastewater Treatment Plant Biomethane Project will create biogas from human waste which will be fed into the area’s existing natural gas distribution system. Expected to be operational in July 2009, this pilot project will provide enough energy for 100 homes and will be the first human waste-to-energy project in British Columbia.
A study done at the University of Texas, Austin estimates that the livestock industry in the United States produces 1 billion tonnes of manure annually. If this were used to generate biogas and then electricity, up to 3% of total US electric demand could be met.
The Vintage Dairy Biogas Project will produce enough biogas to power 1200 homes a day in California. The biogas produced will be fed into the natural gas distribution system and used in a PG&E; power plant in Northern California.
Leading off the year’s waste-to-energy news was a piece on how Heiger International Uganda is working with several partners to build biogas plants, using human excrement and a mixture of banana peels, algae, water hyacinth and chicken manure as the feedstock. The biogas isn’t being feed into a grid like the projects in Canada and the United States, above, but is being used for cooking, lighting and in various types of engines.