[audio:http://wamcradio.org/EarthWise/wp-content/uploads/2014/04/EW-05-05-14-Biomass-Fuel-Cell-.mp3|titles=EW 05-05-14 Biomass Fuel Cell]
Fuel cells convert chemical energy from fuel into electricity using a chemical reaction with an oxidizing agent. The most common fuel cells run on hydrogen, but hydrocarbons like methanol are also used. Biomass has not been used in fuel cells because, until now, there has been no effective catalyst to break down complex organic materials.
Recently, researchers at the Georgia Institute of Technology have developed a new kind of fuel cell that can produce electricity directly from biomass using a catalyst activated by solar or thermal energy. The fuel can be almost any kind of biomass including starch, cellulose, switchgrass, powdered wood, algae or even waste from poultry processing.
In order to make a fuel cell from biomass, the polymer bonds of the material must be broken down, which is not easy to do. The Georgia Tech researchers have come up with a polyoxometalate catalyst that is activated by light from the sun or by heat. The catalyst acts both as an oxidation agent and a charge carrier. The energy output has the potential to match that of methanol fuel cells.
There is much work to be done before such a device can become practical, but it could represent a low-cost electrical energy source that is completely sustainable, being powered by the sun and by biomass. It isn’t exactly the “Mr. Fusion” device that powered the DeLorean car in the Back-to-the-Future movies, but it is one step closer to a power supply that runs on organic waste.
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Solar-Induced Hybrid Fuel Cell Produces Electricity Directly from Biomass
Photo, taken September 17, 2008, courtesy of the Idaho National Laboratory via Flickr.
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Earth Wise is a production of WAMC Northeast Public Radio. Support for Earth Wise comes from the Cary Institute of Ecosystem Studies in Millbrook, NY.