What’s the only thing better than gasoline? Audi’s bio-gasoline, produced by genetically engineered bacteria

German auto company Audi has entered a partnership with Global Bioenergies to continue work on a new biofuels technology that they hope could make synthetic production of gasoline a viable alternative to extracting it from the Earth. Since the carbon used in making synthetic gasoline is drawn from existing biomass and the atmosphere, it is sometimes called “green gas,” though it’s still not entirely carbon neutral. The Global Bioenergies system can churn through everything from corn to wood chips (with varying efficiency), and can be used by any normal gas-burning vehicle. Being a “drop in” solution greatly increases the technology’s chances of being adopted.

The primary advantage of this new form of biofuel production is that it focuses on creating a molecule less toxic than ethanol. As anyone who’s ever tried making wine will know, yeast and other microorganisms that release ethanol tend to kill themselves when kept in an enclosed space; most yeast species poison themselves with their own waste product, requiring distillation to get much higher than about 20% alcohol by volume. The same principle holds for ethanol in most other contexts — but ethanol isn’t the only molecule we can make.