Forget hybrids, electric vehicles or hydrogen cars. Scientists at the University of California, Los Angeles, want your poo to fuel the cars of the future. The United States produces a mountain of manure (human and otherwise) every year: more than 1 billion tonnes. All that waste matter is being wasted in turn, according to UCLA graduate student David Wernick, pumping greenhouse gases into the atmosphere to boot. That's why he and his colleagues are trying to use it to produce new kinds of biofuels. "We're working with anything, such as agricultural waste like manure, municipal waste like sewage, plant matter, cellulosic matter, and even carbon dioxide out of the atmosphere," Wernick said in a new video about his research.
When it comes to liquid fuels, the market is dominated by petrol, diesel and jet fuel — all hydrocarbon compounds derived from crude oil. There's very good reason for that. Such fuels are cheap, abundant (for now), and highly energy-dense. In general, the greater the energy density of your fuel, the better, since it means you can store or transport a lot more energy in the same volume. They also have a comparatively high energy conversion efficiency rate.
To date, biofuels like the corn-derived ethanol just haven't been able to compete with liquid fossil fuels. Ethanol also corrodes metal pipes, and isn't compatible with the existing infrastructure. You need special modifications to run your car on ethanol or similar biofuels.
Wernick and his UCLA cohorts think they can take biofuels to the next level by engineering bacteria (Bacillus subtilis) to be more efficient at breaking down the proteins in human excrement, as well as other protein-rich waste such as wastewater algae and all the byproducts from fermenting wine, ethanol and beer.
"The vast majority of organisms out there don't consume protein to convert it into a product," Wernick explained. "They find protein in the environment and then use that to grow." His re-engineered bacteria will use some of the protein to produce poo-based biofuels instead — with no need for rejiggering automotive technology: "You can drop it right into your car."
All hail the power of poo.
University of California, Los Angeles