Solar energy typically works by using solar panels to convert sunlight into electricity. The next big step for solar power will be figuring out how to turn sunlight into liquid fuel.
A team of Harvard scientists set took on the task: The scientists used what's known as an "artificial leaf" to harness sunlight to separate water into hydrogen and oxygen—similar to how photosynthesis works in plants.
They then took the hydrogen and feed it to a bacterium called Ralstonia eutropha. An enzyme in the bacterium breaks the hydrogen down into its atomic parts, which are then combined with carbon dioxide.
Finally, the scientists engineered the bacterium to convert the hydrogen‑carbon dioxide mixture into isopropanol—a type of industrial alcohol currently used mainly as a cleaning agent or solvent, but that could potentially be used as motor fuel, too.
At this stage, the scientists are concentrating on tinkering with the process to make it more efficient.
The process won't replace gasoline made from oil any time soon. After all, most internal combustion engines are not designed to run on isopropanol or alcohol generally. But using bacteria to create fuel could eventually become a useful way to produce fuel, especially in developing countries where gasoline is not always available.
"Bionic Leaf: Researchers Use Bacteria to Convert Solar Energy Into Liquid Fuel" (Phys.org)