Audi has announced plans to pursue their objective of developing synthetic fuels and now they have started making e-diesel by using air, water and green electricity. Their newly established Sunfire plant is capable of producing e-diesel thanks to the “power-to-liquid principle” and it only needs raw materials like water, electricity and carbon dioxide.
As you would expect, the process is far from being simple and the company says they are able to extract carbon dioxide from air by using a direct air capture technique invented by Climeworks. There’s also an electrolysis unit in another section of the plant which splits the water into hydrogen and oxygen and runs on green electricity.
After that, the hydrogen reacts with the carbon dioxide through two chemical processes which take place at 428 degrees Fahrenheit (220 degrees Celsius) and a 25-bar pressure in order to generate an energetic liquid called “Blue Crude” and made from hydrocarbon compounds.
According to Audi, the Sunfire plant can produce around 160 liters of Blue Crude each day and almost 80 percent of it can be transformed into e-diesel which doesn’t have any sulfur and ignites right away since it has a high cetane number. The company also mentions it’s compatible with cars as thanks to its chemical properties it can be blended with fossil diesel in any ratio.