Wednesday, May 234 2006
Better Fuel Cells Using Bacteria
Bioengineer Tim Gardner says synthetic biology could create bacteria that produce electricity from waste more efficiently.
By Emily Singer
What if you could power your house with sewage? Or run your pacemaker with blood sugar rather than a traditional battery? Scientists hope that microbial fuel cells -- devices that use bacteria to generate electricity -- could one day make this vision a reality.
While typical fuel cells use hydrogen as fuel, separating out electrons to create electricity, bacteria can use a wide variety of nutrients as fuel. Some species, such as Shewanella oneidensis and Rhodoferax ferrireducens, turn these nutrients directly into electrons. Indeed, scientists have already created experimental microbial fuel cells that can run off glucose and sewage. Although these microscopic organisms are remarkably efficient at producing energy, they don't make enough of it for practical applications.