We’ve all heard about the unlimited power of the sun. Engineers are getting some of it in an unusual way. Sunshine and bugs. Today, on Engineering Works!
One of the problems with using electricity from the sun, or anywhere else, to power things like cars and trucks is that electricity is not very energy dense. This means that a pound of battery won’t take you as far as a pound of gasoline. The difference gets more important the farther you want to go.
Chemical engineers are working on a way to use electricity from the sun – photovoltaics – to power a biological reaction that uses genetically modified microbes, bacteria, to produce an energy-dense liquid fuel called butanol.
The microbe the researchers are using already is used in industrial processes to produce non-fossil-fuel-based plastics. By modifying the bacterium’s genetics, they get it to turn out butanol instead. It all happens when electricity from solar-powered photovoltaic cells starts a reaction that produces a substance the bacterium eats. Out comes the butanol and carbon-dioxide. The CO2 is recycled back into the reaction. It’s pretty slick.
There are still problems with the process: It quits after about 80 hours. But the researchers are confident they can tweak it so it runs longer. And, they say, their results point the way to using the bacterium to turn out other energy-dense liquid fuels.
Our energy is getting pretty thin, and we’re done. See you next time.
Engineering Works! is made possible by Texas A&M Engineering and produced by KAMU-FM in College Station. Learn more about engineering. Visit us on the World Wide Web.
Start the discussion: This is cool stuff, so cool it seems almost too good to be true. What do you think?