Electrical current from solar cells run on an electrode in an environment of water, CO2 and Ralstonia eutropha, causing chemical reactions. In response, the bacteria of Ralstonia eutropha consuming formate (including CO2 associated with a hydrogen atom) and production of biofuel butanol.

Scientists call this fuel is electrofuel. Expert Liao said: "In principle, we can approach this way to obtain fuel or other chemicals."
The study was a U.S. Federal government funded and published in the journal Science.