I am a laid back guy, but wasting food really bothers me. There are people in the world who would kill for that half-finished burger or apple you took two bites out of. But I’m also not one of those “freegans” who rummage through peoples’ trash either. Sometimes bad food is bad food, and it is simply inedible. But what if we could harvest all of that wasted food, and turn it into fuel?

There’s an obvious Mr. Fusion reference there that I am going to resist making, but it isn’t just Hollywood movie magic It’s a real idea by the Fraunhofer Institute for Interfacial Engineering and Biotechnology. The Fraunhofer Institute has built a pilot waste-food-to-fuel plant in Stuttgart, Germany, next to a wholesale fruit market.At the end of the day, the waste and rotted vegetables are scooped up and dumped into a bioreactor, where the waste ferments into a sustainable biomethane. As ze Germans would say, Wundabar!

The plant relies on rotting fruits and veggies, where natural decay has already decomposed the tough lignin structure that makes breaking down fresh plants so tough. As a result, the fermentation process lasts just a few days, depending on the acidity of the fruits inside, resulting in a clean-burning biomethane fuel. This same idea is being applied in the developing world as well, where human waste is gathered up and fermented to make methane. Compared to human poo, rotting fruit must seem absolutely benevolent.

As an added bonus, the biofuel plant also reuses all of the runoff from biomethane production, like the liquid filtrate, which is fed to algae farms that produce a biodiesel fuel. CO2 from the fermentation process also feeds the algae farm. Though strictly a test plant, this demonstration could provide local farmers with the means to fuel up on otherwise rotten fruit. Just take the day’s leftovers to the fueling station, and trade in your rotten fruit for freshly-made fuel.

It may not save the world, but every little step forward helps.

Source: Fraunhofer