The Department of Energy’s Advanced Research Projects Agency-Energy (ARPA-E) has again given a grant of $1million to another project led by Derek Lovley and his team at the University of Massachusetts (Amherst). The team is working with Geobacter bacterium to produce butanol costing as little as $2 per gallon. The interesting part is that the fuel is not produced through conventional photosynthesis from sugar, but through electricity. Another team at Harvard Medical School’s Wyss Institute is working with Shewanella oneidensis to produce octanol. Because this new mechanism has no official name, they explain it as an equivalent of a reverse fuel cell.
They grow these bacteria on a surface of a graphite electrode by using solar panel energy, which is 100times more efficient at capturing sunlight. Naturally, these bacteria generate electricity through their long protein tubes. But the researchers can reverse-engineer this to make the bacteria take up electrons from the electrode. And with an addition of a photosynthetic pathway modification n these bacteria allow them to generate butanol or octanol.