There is no denying that Audi is a really innovative car brand. It is evident even in the selection of different fuels that their cars are using: petrol, diesel, electric, hybrid and natural gas powertrains are mounted in a huge variety of models. Now Audi is presenting a method for producing the synthetic fuel, called Audi e-gas, which is used to power g-tron cars.
Audi is partnering with the Viessmann Group and opening a new factory which will produce the synthetic fuel in a new way. Usually, Audi e gas is made in a two steps process. Firstly, water is split into hydrogen and oxygen in an electrolysis reaction, using renewably generated electricity. Then hydrogen is reacted with carbon dioxide to produce synthetic methane. This process requires high pressure and high temperature. In the new factory, which has just been opened in Allendorf in the German state of Hesse, methanation is now purely biological, which means that specialized microorganisms are used.
These highly specialized organisms are able to absorb the hydrogen form a liquid through their cell walls. Connecting hydrogen and carbon dioxide they create methane – neither high pressure of extremely hight temperature is needed for the process. This plant is the first of its kind using biological methanation in Germany.
In its opening ceremony Reiner Mangold, Head of Sustainable Product Development at AUDI AG, said: “We are writing the next chapter of the Audi e gas story here. Audi began to produce the sustainable fuel in Werlte around two years ago. Now we are also working with a partner who immediately contributed this new process.”
Biological methanation has many advantages over the chemical one. Probably the biggest one is that the carbon dioxide does not need to be present in high concentration or purified form. This means that CO2 can be taken from smaller plants that do not perform biogas purification (such as sewage treatment plants).
Production of e-gas is extremely important for Audi and company is likely to keep working with this technology. It already has g-tron cars in its range – Audi A3 Sportback g-tron has been on the market since the beginning of 2014 and a new Audi A4 Avant g-tron should enter the market at the end of 2016. Natural gas powered cars are extremely environmentally and user friendly. Same car can be run on petrol, conventional natural gas, biomethane or the sustainably produced Audi e gas. Audi A3 Sportback g-tron emits less than 100 grams of CO2 per kilometre and should be very cheap to run.
Audi e gas is one possible answer to strict environmental regulations. G-tron cars maintain most of characteristics of conventional petrol cars, yet are much cleaner and cheaper to run. New ways to produce this synthetic gas and the new factory just shows how keen Audi is on this technology and we can expect g-tron range to expand in the near future.