Audi is out with its latest batch of synthetic fuel. It’s called “e-benzin” and as the word synthetic implies, there’s not a drop of petroleum in it.
Audi’s “e-benzin” is developed in partnership with Global Bioenergies and it’s made using biomass, instead of fossil fuels. Although researchers hope to even eliminate even the need for biomass in the future. The result is a 100-percent iso-octane fuel that burns cleanly since it doesn’t contain sulfur or benzine.
Audi says all of this results in a high-grade fuel that enables engines to use high compression ratios for enhanced efficiency. It plans to test the new fuel in the lab and in test engines. It hopes to also modify the process so that it requires no biomass to produce, instead requiring just water, hydrogen, CO2 and sunlight.
“Global Bioenergies has demonstrated the viability of the Audi “e-benzin” production process. That is a big step in our Audi e-fuels strategy,” said Reiner Mangold, Head of Sustainable Product Development at AUDI AG.
Audi is already producing larger quantities of “e-gas” (synthetic methane) on an industrial scale for its customers. Other research projects with various partners are dedicated to Audi “e-ethanol” and Audi “e-diesel”.
In April, Audi started producing its first batches of synthetic e-diesel. The first five liters fueled up an Audi A8 3.0 TDI clean diesel quattro. Audi says no mineral oil is needed to make it. It’s produced using water and C02 at a pilot plant in Germany.
If you’re interested in learning more about how e-diesel is made, here is an excerpt from Audi’s press release.
Production of Audi e-diesel involves various steps: First, water heated up to form steam is broken down into hydrogen and oxygen by means of high-temperature electrolysis. This process, involving a temperature in excess of 800 degrees Celsius, is more efficient than conventional techniques because of heat recovery, for example. Another special feature of high-temperature electrolysis is that it can be used dynamically, to stabilize the grid when production of green power peaks.
In two further steps, the hydrogen reacts with the CO2 in synthesis reactors, again under pressure and at high temperature. The reaction product is a liquid made from long-chain hydrocarbon compounds, known as blue crude. The efficiency of the overall process – from renewable power to liquid hydrocarbon – is very high at around 70 percent. Similarly to a fossil crude oil, blue crude can be refined to yield the end product Audi e-diesel. This synthetic fuel is free from sulfur and aromatic hydrocarbons, and its high cetane number means it is readily ignitable. As lab tests conducted at Audi have shown, it is suitable for mixing with fossil diesel or, prospectively, for use as a fuel in its own right.
Stay tuned for what’s next in Audi’s growing synthetic fuel lineup.
Photo Credit: Audi