In the United States, gasoline is already sold as a blend with up to 10 percent ethanol, but this hardly represents a solution to fossil fuels. Not only does ethanol have a low energy density, but it can be corrosive to engines. The search for a truly sustainable, long-term fuel replacement for use in combustion engines will likely need to come from elsewhere.

That's where beer comes in. Chemists at the University of Bristol recently created a sustainable petrol, and their magical ingredient was suds, reports Phys.org.

Using beer as a fuel might seem like a terrible waste of a good drink, but interestingly enough, the process of making ethanol for fuel is much the same as brewing beer. It's not so much that scientists are expecting you to pour your next six-pack into your car's gas tank, but rather that the process of making beer-- and the unique mixture of ingredients at play in beer-making-- might make for a good model of how we can brew a better ethanol.

And what makes for a better ethanol? Ideally, we want an ethanol that can be easily converted into butanol, a substance that makes for a far more suitable, less corrosive fuel.

"The alcohol in alcoholic drinks is actually ethanol — exactly the same molecule that we want to convert into butanol as a petrol replacement," explained Duncan Wass, a University of Bristol chemist whose team led the research. "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."

How it works

Researchers used a chemical catalyst that works particularly well when used with beer to create their butanol. Their research further demonstrates that this methodology can be scaled up for industrial application.

"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. "Beer is actually an excellent model for the mixture of chemicals we would need to use in a real industrial process, so it shows this technology is one step closer to reality."

Before the technology can be put to industrial use, however, the team needs to study what exactly it is about beer that makes their catalysts so successful when used with it. They can then mix a specialized brew specifically for the purpose of making a fuel without having to sacrifice any real ale in the process. So beer connoisseurs can relax.

"We wouldn't actually want to use beer on an industrial scale and compete with potential food crops," assured Wass.

The research was published in Catalysis Science & Technology.