Fuel for thought

In its constant search for new, cleaner and more efficient means of mobility, Audi is continuing its extensive work into the production of alternative fuels, with a new pilot facility for the production of e-diesel in Laufenburg, in Canton Aargau (Switzerland). For the first time, the energy needed will be supplied from the renewable source of hydropower, with the planned facility having a capacity of around 400,000 litres per year. 

The pilot facility is just the latest in ongoing research by Audi into climate-friendly, CO2-based fuels such as e-gas, e-petrol and synthetically manufactured e-diesel fuel.

“At the project in Laufenburg, thanks to a new technology we are able to handle the production of e-diesel efficiently in compact units, making it more economical. The pilot facility offers scope for sector coupling, in other words combining the energy sectors power, heat and mobility, and makes it possible to store renewable energy,” explains Reiner Mangold, Head of Sustainable Product Development at AUDI AG (pictured above). 

Audi e-diesel has the potential to make conventional combustion engines operate almost CO2- neutrally. To produce it, the power-to-liquid plant converts surplus hydropower into synthetic fuel. 

A chemical principle is applied: The green power generated on site in the hydroelectric power station produces hydrogen and oxygen from water by means of electrolysis. In the next step the hydrogen reacts with CO2, using an innovative and very compact microprocess technology. 

The CO2 can be obtained from the atmosphere or from biogenous waste gases and, as with all Audi e-fuels, is the only source of carbon. Long-chain hydrocarbon compounds are formed. In the final process step these are separated into the end products Audi e-diesel and also waxes, which are put to use in other areas of industry.

This new project in Laufenburg will see Audi work with partners Ineratec and Energiedienst AG and is Audi’s second partnership in a pilot facility that operates according to the power-to-liquid principle. Audi has already been working together with the energy technology corporation sunfire in Dresden since 2014. There, sunfire is exploring the manufacturing of e-diesel using the above principle, but involving different technologies. The other Audi e-fuels projects include its own power-to-gas facility in Werlte, north Germany, which makes Audi e-gas – in other words synthetic methane – for the g-tron models A3, A4 and A5. The Ingolstadt carmaker is also researching the manufacture of e-petrol together with specialist partners.