New research suggests that ethanol like that created during the brewing process could be used to create the more practical gas alternative known as butanol.
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Setting aside all the other issues surrounding traditional gasoline, the crude oil used to make it is a finite resource, so at some point in a future, a renewable option will become a must. But while many big names are turning towards the idea of electric vehicles, scientists at the University of Bristol have been looking into a different and unlikely source: beer.

According to the college, a team of chemists have figured out a way to turn the ethanol in beer – which can be used for biofuels, but only in a limited capacity – into the more practical butanol, which could serve as a sustainable alternative to gasoline. Researchers have been able to turn “pure, dry” ethanol into butanol in the laboratory in the past, but to truly make this method feasible for large scale use, scientists needed to prove they could convert industrially-fermented ethanol – like the kind found in beer – into butanol. “Alcoholic drinks are an ideal model for industrial ethanol fermentation broths – ethanol for fuel is essentially made using a brewing process,” explained Professor Duncan Wass, whose team led the project. “If our technology works with alcoholic drinks (especially beer which is the best model) then it shows it has the potential to be scaled up to make butanol as a petrol replacement on an industrial scale.”

Importantly, using literally beer on an industrial scale is impractical if for no other reason than it’s a waste of beer. But the process for brewing beer is similar to the initial steps for making butanol from ethanol, so these researchers see their recent success as a big first step. “Turning beer into petrol was a bit of fun, and something to do with the leftovers of the lab Christmas party, but it has a serious point,” said Wass. “We wouldn’t actually want to use beer on an industrial scale and compete with potential food crops. But there are ways to obtain ethanol for fuel from fermentation that produce something that chemically is very much like beer - so beer is an excellent readily available model to test our technology.”

The University of Bristol team says that building this type of conversion out to a larger scale process is still probably five years or more away. Still, in brewing, you probably shouldn’t open a brewery if you haven’t learned how to homebrew. Consider this study a similar initial learning process.