Recently I’ve come across a series of articles all sharing the common theme of energy generation using micro-organisms. First up, we have a report from Stanford University of researchers who have successfully short circuited photosynthesis in plant cells to generate electricity. By inserting an ultra-sharp nanoelectrode made of gold into the chloroplast of algal cells they were able to collect electrons which had been excited by absorbed light. The total current: one picoampere. Also the cells die after about an hour. However, the researchers do note that the process could theoretically generate carbon free electricity, provided it could scale up to useful levels. Next, the Office of Naval Research will be unveiling their new microbial fuel cell tomorrow. “These cells convert marine oxidants and fuels into electrical energy, thereby providing an efficient, reliable and clean alternative to batteries. These cells can be used to power in-water sensors and underwater unmanned vehicles among others.” In particular, the microbe Geobacter, which can generate electricity from wastewater and mud. A very handy trick! Finally, a team of Penn State engineers have discovered a microbe that can use electricity to convert carbon dioxide and water to methane. Boasting 80% efficiency, these microbes are being suggested as a possible means of storing off-peak electricity from wind or solar sources by converting electricity to a burnable fuel.
All of these potential microbial energy sources remain experimental or small scale, however, it was pretty cool to see the possibilities for clean energy production they suggest.