Called e-diesel, the fuel developed in collaboration with Dresden-based Sunfire, was created in a lab using a simple but innovative technique. The scientists began by boiling water to temperatures exceeding 800°C (1,472°) using a renewable source of energy like solar, wind or hydropower. The resulting steam was decomposed into its twoconstituents, hydrogen and oxygen with the help of electrolysis. The researchers then transformed the carbon dioxide to carbon monoxide. The hydrogen and carbon monoxide were piped into a reactor and subjected to extreme pressure and temperatures, to produce what scientists call long-chain hydrocarbons. This liquid that Audi refers to as "blue crude" was then refined in a similar way to standard crude oil to produce e-diesel.