There are also short-term practical implications. "Once you realize that there are methane producers that can directly feed on electrons, you start thinking differently about how to optimize methane production from wastes," the microbiologist notes. "Although generating methane from wastes is one of the oldest bioenergy strategies and is practiced even in small villages in developing countries, its application on a large scale has been limited because it is slow." Trying to speed methane production in large-scale operations can disrupt the microbes' highly coordinated activity and systems can fail.
These communities evolved over billions of years to slowly convert organic matter to methane, Lovley explains. "Electrical circuitry that evolved for microbes to make methane from organic matter in swamps at their own leisurely pace may not match our wish for a faster process in waste digesters. Just as you need to upgrade electrical service in your house when you add more appliances, we made need to use synthetic biology or other engineering approaches to increase the capacity to move current through methanogenic microbial communities in digesters."
With the Massachusetts Department of Environmental Protection planning to begin in January 2014 phasing in a requirement that large-scale food service operations such as grocery stores, universities and correctional facilities compost food waste to increase diversion from landfills by 350,000 tons per year by 2020, anaerobic biodigesters may soon be very important to the state's business community. The new advances from UMass Amherst research could help to significantly improve their design and efficiency, Lovley notes.
|Contact: Janet Lathrop|
University of Massachusetts at Amherst