Thanks to scientists and their ingenious ways, we’re closer to being able to generate alternative fuel using electricity and carbon dioxide. The breakthrough is the result of efforts by researchers at UCLA Engineering who have demonstrated a method whereby CO2 can be turned into liquid fuel isobutanol through electricity. A study published in the journal, Science, reported that the scientists have devised a new technique for electrical energy storage as chemical energy, which can then be used as liquid fuel.
For long, storing electrical energy has been a problem due to low density or incompatibility with transportation infrastructure. At present, energy is stored in lithium ion batteries. However, the density tends to become low. The scientists found that if energy is stored in liquid fuel, density is much higher, proving that this could be the new way to go about powering vehicles without changing existing infrastructure.
James Liao and his team genetically modified Ralstonia eutropha H16 or what’s known as a lithoautotrophic microorganism to produce 3 methyl 1 butanol (methyl isopropyl carbinol) and isobutanol in an electro bioreactor. CO2 was made the sole source of carbon while electricity was the sole energy output. The boffins used photovoltaics to convert sunlight into electrical energy and then into a chemical intermediate. The latter was further used to power CO2 fixation to produce fuel.
The process was inspired by biological photosynthesis. Instead of using hydrogen generated by solar power to drive CO2 conversion, the scientists made use of formic acid as hydrogen has stability issues and a low mass transfer rate. The acid was used to drive carbon fixation in bacteria to produce higher alcohols and isobutanol.
Liao claims that the scientists will be looking to fine tune and scale up the process, now that the principle has been demonstrated. It is hoped that besides generating alternative fuel, the process will be used in biomass refinery.