Audi starts production of e-diesel using water and CO2

Aware of the growing use of fossil fuels, Audi has started production of e-diesel which uses only water and carbon dioxide as raw material. This breakthrough alternate fuel has been produced in Dresden, Germany using power-to-liquid(PtL) principle.

The process begins with water being broken down into hydrogen and oxygen by means of high-temperature electrolysis. The hydrogen is made to react with CO2(extracted from ambient air and a nearby biogas plant) in synthesis reactors under high pressure and temperature. The reaction product - made from long chain hydrocarbon compounds - is known as blue crude. This product is later refined to convert into what Audi terms as e-diesel.

This synthetic fuel is free from sulphur and aromatic hydrocarbons and can be used as fuel. Audi claims the efficiency of this entire process - from renewable power to liquid hydrogen carbon - is 70%.

Reiner Mangold, Head of Sustainable Product Development at Audi said: “In developing Audi e-diesel we are promoting another fuel based on CO2 that will allow long-distance mobility with virtually no impact on the climate. Using CO2 as a raw material represents an opportunity not just for the automotive industry in Germany, but also to transfer the principle to other sectors and countries.”