Researchers may have found a way to reduce the environmental impact of air travel in situations when electric aircraft and alternative fuels aren’t practical. Wired reports that Oxford University scientists have successfully turned CO2 into jet fuel, raising the possibility of conventionally-powered aircraft with net zero emissions.

The technique effectively reverses the process of burning fuel by relying on the organic combustion method. The team heated a mix of citric acid, hydrogen and an iron-manganese-potassium catalyst to turn CO2 into a liquid fuel capable of powering jet aircraft.