Push for the energy revolution

Audi is engaged in the production and development of renewable fuels. The Audi e-fuels – Audi e-gas, e gasoline and e-diesel – reduce CO2 emissions by up to 80 percent. How well do the fuels truly meet the needs of the customers, and what are their prospects in the medium term? Reinhard Otten, specialist manager for climate protection and resource conservation, answers our questions.

11/13/2018 Reading Time: 5 min

Mr. Otten, what exactly is the idea behind the Audi e-fuels?
Reinhard Otten:
The Audi e-fuels are sustainable fuels during the production of which the same amount of CO₂ is bound that the car emits during operation on the road. The carbon dioxide is thus managed within a cycle; it changes from a pollutant to a valuable material. The driving force in the production of Audi e-fuels is renewable energy.

Audi e-gas, Audi e-gasoline and Audi e-diesel – what can you tell us about them?
Audi e-gas is synthetic methane. For the last five years, we have been producing a portion of the required Audi e-gas in a power-to-gas plant in Werlte (Emsland) that we built in collaboration with our project partners. The e-gas is produced in a two-step process from renewable energy, water and CO₂. The latter is provided by an adjacent waste biogas plant. Our e-gas is suitable for powering internal combustion engines designed for operation on natural gas ...

... which Audi also offers with its g-tron model.
Exactly. We currently have one g-tron model in each of the Audi A3, A4 and A5 model families. Because we use CO₂ that would have entered the atmosphere anyway and avoid the combustion of fossil fuels, operation with Audi e-gas is virtually CO₂-neutral. And renewable electricity provides 100 percent of the energy we need for production. The power-to-gas plant is started up prioritarily when the region’s wind and solar power plants produce more electricity than the local grid can absorb.

“Mathematically speaking, Audi g-tron customers, consume no fossil natural gas.”

Reinhard Otten

But customers can’t fill up with Audi e-gas directly.
No, it is distributed via the natural gas network to roughly 3,500 CNG refueling stations throughout Europe. Our g-tron customers purchase the e-gas indirectly via a certified offset process. This ensures that the amount of CNG drawn is replaced by feeding a corresponding amount of sustainable method into the network. We base this on the actual mileage driven by the g-tron vehicles, which is continuously recorded by After Sales Service. Mathematically speaking, Audi g-tron customers, therefore, consume no fossil natural gas.

What is the status of the other two alternative fuels?

Two partner companies and we will soon begin with the construction of an industrial plant for the production of Audi e-diesel in Laufenburg on the Swiss side of the Rhine. There, we are using hydro power as the energy source for a process that initiates with water and CO₂, just like in Werlte. With Audi e-gasoline, we have just completed the laboratory stage. A few months ago a plant in Leuna produced the first 60-liter (15.9 US gal) batch, which is now being tested in test engines.

“No one can now seriously assert that we can’t switch to 100-percent renewable energy.”

Reinhard Otten

How is your team at Audi structured?
Our core e-fuels team is small, but potent. The people come from a wide range of disciplines: automotive engineering, chemistry, biology, environmental engineering. We are in dialogue with every key development organization within the company, primarily with our colleagues in Drive Development.

You have some tough nuts to crack. What motivates you?
The fact that we can make a major contribution to the energy revolution with our Audi e-fuels. Our Audi e-gas plant in Werlte works according to the power-to-gas principle. It converts electricity from instable energy sources such as wind or solar into natural gas, thus enabling it to be stored. The plant was the first of its kind worldwide and ushered in a new way of thinking and many successor projects throughout the energy industry. No one can now seriously assert that we can’t switch to 100-percent renewable energy. The storability of electricity is the key to doing this.

“I love the idea that we, as an automobile manufacturer, could become the driving force behind an essential energy revolution technology.”

Reinhard Otten

How did this all get started?
Eight years ago, I was pondering the challenges of the energy revolution and sketched the principle of such a plant, which at the time only a handful of scientists had ever heard of, on a piece of paper. I said over and over again that power-to-gas technology could make our future electric, hydrogen and CNG cars sustainable. An Audi colleague and I, who today is my boss, were then able to convince more and more people at the company of our idea – up to and including the Board of Management. We are proud of that. I personally think it’s great that you can really accomplish something in a team here.

But let’s be honest now. Do the Audi e-fuels have a chance to establish themselves on the market, or is their production simply too expensive?
They will definitely establish themselves sooner or later; the question of when depends on a variety of factors. One is the price of crude oil on the global market; another is the assessment by policy makers that the new fuels are alternatives that are required today. One powerful lever could be to apply the CO₂ reduction as a result of e-fuels to the manufacturer’s fleet fuel consumption. The production of e-fuels could become economical very quickly, particularly with the combination of g-tron and e-gas. I love the idea that we, as an automobile manufacturer, could become the driving force behind an essential energy revolution technology. This idea motivates me every day.

Which energy source will win out in the long run? Green fuel or green electricity?
Both. There is a clear trend toward electric mobility in many key markets, but electric mobility alone cannot bring about the desired reduction of greenhouse gas emissions. For a variety of reasons, it simply cannot be rolled out quickly enough. Given the very diverse markets and target groups, we must complement electric mobility with renewable energy sources for the many vehicles with combustion engines that will remain on the road for many years to come.

These e-fuels don’t necessarily have to be produced in Germany, by the way. They could also come from sun drenched northern Africa, for example. And if the day comes when they are no longer required for automobiles, there are other industries that make a case for them, such as the plastics industry, road freight transportation or even aviation and marine transport. Today our new fuels are an Audi USP and a demonstration of Vorsprung durch Technik, but they are necessary if we are to achieve our climate goals in addition to being technology- and user-agnostic.

Reinhard Otten, Sustainable Product Development AUDI AG

Reinhard Otten, Sustainable Product Development AUDI AG

Reinhard Otten

Reinhard Otten was born in 1968 in Lemgo, Germany. After graduating high school in Bad Schwartau, he studied automotive engineering at the Technical University of Berlin, focusing even then on alternative drive systems. He worked as an automotive journalist in 1994 and 1995 before joining AUDI AG in early 1996. Following various assignments in Product Marketing and Sales, including in Spain, Otten transferred to Technical Development in 2002, where he specialized in environmental and energy topics.

From 2010, he supported the planning and construction of the Audi e-gas plant in Werlte as a strategist and deputy project manager. The plant built on his initiative went on stream in 2013. Since fall 2017, Reinhard Otten has served as a specialist manager responsible for the climate protection and resource conservation strategy in the area of product sustainability.


alternative drive systems


In addition to engine efficiency, we also monitor the ecology of the entire energy system in the Audi g-tron models and for Audi e-gas as a fuel.

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