Running an electric car on electricity is something pretty common (and logical), but running a gasoline car on electricity is something of fantastic realm. Still, a team of UCLA scientists have succeeded doing this – they produced high-grade alcohol by using electricity and fueled an internal combustion engine with it.
“The current way to store electricity is with lithium ion batteries, in which the density is low, but when you store it in liquid fuel, the density could actually be very high. In addition, we have the potential to use electricity as transportation fuel without needing to change current infrastructure,” said James Liao, UCLA’s Ralph M. Parsons Foundation Chair in Chemical Engineering.
By genetically engineering Ralstonia eutropha H16, a lithoautotrophic microorganism, they made it produce isobutanol and 3-methul-1-butanol. They used carbon dioxide as the only source of carbon and had the process going on with the help of electricity.
Photosynthesis, as Liao explains, is a two-part process: the light reaction and the dark reaction. The first converts photons into chemical energy and the second, going on in the plant’s own guts, converts CO2 to sugar, and doesn’t need light.
“We’ve been able to separate the light reaction from the dark reaction and instead of using biological photosynthesis, we are using solar panels to convert the sunlight to electrical energy, then to a chemical intermediate, and using that to power carbon dioxide fixation to produce the fuel,” Liao said. “This method could be more efficient than the biological system.”
Liao’s team used a slightly modified approach to the photosynthesis process. They basically split up the two sub-processes so that the first (which results in the production of hydrogen) takes place by electrolysis with the energy from solar panels, for example, and the second takes place in a reactor containing the lithoautotrophic microorganisms.
However, they discovered that hydrogen was not the best energy carrier for this purpose. They instead used formic acid as the intermediary, which they generated by using electricity. Then, the formic acid was used to power the CO2 fixation in bacteria so to produce isobutanol and higher alcohols.
Liao is now thinking of scaling up the entire system – and I think he’ll succeed.
This could also be an important step in the science of giving value to the CO2 we produce, since it can thus be recycled in the most efficient way possible. Now all it matters further is how efficient the actual conversion process is – we know electrolysis can be improved and we also don’t know much about how these microorganisms convert the CO2 and formic acid into alcohols.
We can only wish the best to Liao and his team!