The writing is on the wall. Diesel powered cars are “out”. Many companies now only allow their staff to choose petrol engined cars as their company car. Indeed, leasing companies in our country now push their corporate clients to do so. Soon we will be assisting at a massive resale value loss of diesel engined cars all over Europe, with the average European car owner, the majority of which own a diesel, paying the bill. Actually, this is already happening.

This loss in resale value also threatens the quality cars made in Germany, despite their longevity and mechanical stamina. This is the last thing they want to see. On top of that comes the ban on diesel cars in cities, which is now legally possible in Germany. In the light of all these uncertainties, who wants to purchase an expensive (German made) diesel with an expected long service life?

So something has to be done, in order to save the millions of owners of (German) diesel cars of financial disaster and even the possibility that they are not able to use their car any more for worry free urban mobility.

Audi has worked on it, since 2014. They come up with “clean” e-gasoline and e-diesel fuel. After this report here was published on our site, we talked to the Audi people in Germany, and they added some further comments based on out further questions. Just read on what they have achieved so far, and find their answers at the end of our report…

Hans Knol ten Bensel

Audi e-gas is already on the market, and a new e-diesel pilot plant is being planned. 

Audi is convinced of the potential of the fuels e-gas, “e-benzin” (e-gasoline) an e-diesel and is continuing to pursue its e-fuels strategy. In the case of synthetic Audi “e-benzin” (e-gasoline), the Ingolstadt company has now achieved an important intermediate goal. Together with their development partners, they have for the first time produced a sufficient quantity of regeneratively produced fuel for initial engine tests.

Together with Global Bioenergies S.A. in Leuna (Saxony-Anhalt), the largest batch of e-gasoline ever produced – 60 liters (15.9 US gal) – has been achieved. “Like all Audi e-fuels, the new fuel has many advantages. It isn’t dependent on crude oil, it is compatible with the existing infrastructure and it offers the prospect of a closed carbon cycle,” said Reiner Mangold, Head of Sustainable Product Development at AUDI AG. Audi “e-benzin” (e-gasoline) is essentially a liquid isooctane. It is currently produced from biomass in a two-step process. In the first step, Global Bioenergies produces gaseous isobutene (C4H8) in a demonstration plant. In the second step, the Fraunhofer Center for Chemical Biotechnological Processes (CBP) in Leuna uses additional hydrogen to transform it into isooctane (C8H18). The fuel is free of sulfur and benzene and is therefore especially low in pollutants when it burns.

Testing…

Audi engineers are now examining the combustion and emission behavior of the renewable fuel in a test engine. As a high-purity synthetic fuel with very good anti-knock properties, Audi “e-benzin” (e-gasoline) offers the possibility to further increase engine compression and thus boost efficiency. Over the medium term, the project partners aim to modify the production process so that it will not require biomass – in this case, CO2 and hydrogen produced from renewable sources should be sufficient source materials.

Audi’s alternative fuels already offer great potential for sustainable mobility and are helping reduce CO2 emissions from combustion engines – by up to 80 percent  in g-tron models, for example.

For Audi, e-fuels are more than just a subject of research in laboratories. Since 2013, the brand with the four rings has been offering renewable Audi e-gas on the market. It originates in part from the company’s own power-to-gas plant in Werlte (Emsland). Customers fill up their Audi g-tron model at any CNG filling station and pay the regular price for it. By feeding the computed volume of Audi e-gas into the natural gas grid, Audi ensures the green benefits of the program, including the corresponding reduction in CO2 emissions.

Audi e-diesel is also part of the Audi e-fuels portfolio. In Dresden, Audi’s cooperation partner Sunfire operated a pilot plant for this purpose from late 2014 to October 2016. As in Werlte, green electricity supplied the energy, and water and CO2 were also used as raw materials. The end product was called Blue Crude, which was refined into Audi e‑diesel. Audi is currently planning production capacity in Laufenburg in the Swiss canton of Aargau. Together with partners Ineratec GmbH and Energiedienst Holding AG, a new pilot plant will produce around 400,000 liters of Audi e-diesel per year. For the first time ever, hydroelectric power is the sole energy supply required for this.

How much “cleaner” this e-Diesel will burn, and how much it will reduce Nox and CO2 emissions, remains now the crucial question, and we asked the Audi people in Germany about this.

They answered the following: “We are still evaluating the quality of this diesel fuel in our test benches. First tests have shown that e-diesel emits less NOx emissions than a normal diesel fuel.

“Furthermore all Audi e-fuels (e-diesel, e-gasoline and e-gas) are able to reduce the CO2 emissions by more than 70 percent”.

Quite encouraging, we will keep you posted in these columns!

Hans Knol ten Bensel