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The automobile is powered up – and under pressure

From e-cars and gas drive systems to plug-in hybrids – it is easy for a layperson to lose track of it all. Prof. Michael Bargende of the University of Stuttgart and Siegfried Pint, Head of Driveline Electrification Development at Audi, discuss where developments are taking us.

Automotive mobility is facing its greatest upheaval ever. Climate change, in particular, is posing formidable challenges for the automotive industry. Politicians are setting increasingly stringent limits that automakers must comply with.

The people at Audi believe there is more than one solution. Customers are already buying the Audi A3 e-tron and the Audi Q7 e-tron quattro – high-performance plug-in hybrids that combine a combustion engine with an electric motor. The new Audi A4 g-tron, on the other hand, is powered by gas. And in 2018 the first purely electric-powered car from Audi will make its market debut. The Audi e-tron quattro concept provided a preview of the car at the IAA in 2015. In the long term, the fuel cell will also have a role to play, as the Audi h-tron quattro concept showed in January at the North American Auto Show in Detroit.


Why are we seeing such varied approaches to alternative drive systems?

Prof. Michael Bargende: In the EU an emissions limit of 70 grams of CO2 per kilometer for 2025 is under discussion, so the automakers would then have to ensure their fleets can meet that requirement. Equipped with a combustion engine alone, only cars that are very lightweight and relatively small would be capable of that. Something really needs to be done.

Siegfried Pint: It takes time for technical developments to catch on and become established. When the combustion engine first emerged, there also was a wide range of different engine and motor concepts. In terms of electrification, the industry is still in the initial phase. That’s why at Audi we are conducting research in several different directions. The Audi e-tron quattro concept shows what we feel the electric car of the future should be – sporty, efficient and suitable for everyday use. Powered by a purely electric quattro drive.


Are alternative drives sufficient for the task of getting our CO2 emissions under control?

Bargende: What we must not do is to in effect move the CO2 from automobile traffic to the power plants. There is no benefit if our cars emit zero CO2, but the carbon dioxide is then produced by our power plants. We need to make sure we aren’t looking at alternative drives in isolation from the bigger picture. No. If anything we must always take into account the entire infrastructure and energy supply structure.

Pint: Audi e-fuels are a possible solution in that regard. With an Audi g-tron, today’s customers can already enjoy climate-neutral mobility if they fill up with synthetic gas. The gas is extracted from CO2 at facilities including the Audi e-gas plant in Werlte. This results in the closed carbon cycle that Professor Bargende is alluding to. For the long term, I also see the fuel cell as an energy source for the automobile of tomorrow.


How do you assess the potential of purely electric-powered cars?

Bargende: With a battery capacity of 50 kilowatt hours, I expect to be able to drive at speeds up to 150 km/h. But if I did, I would be demanding so much from my battery that I would no longer be able to reach my total range of 380 kilometers. The range would then be only 200 kilometers. In my opinion, that is one of the main problems with e-mobility. The statements concerning range must be interpreted independently of a car’s performance.

Pint: I have fewer concerns about range. In the future it’s going to be much more important for a car to be an integral element of the customer’s world. For drivers to be able to use their smartphones to operate a car’s controls, for example. Tomorrow’s customer will get out of the car in front of his or her office and send the Audi off to park itself autonomously in the garage. This is an area where e-drives have major advantages. Piloted parking and driving works much easier with them. And that’s because, unlike with combustion engines, we aren’t dependent on mechanical operation of systems, like gear shifting. In piloted driving mode, the electric car is capable of greater precision than cars with conventional drives.


Nevertheless, insufficient range is something that just doesn’t jibe with our being so accustomed to driving long distances. And then there is the charging problem.

Bargende: Exactly, and especially when driving long distances. The automobile is so important to us because it gives us freedom. We can simply get in and drive without stopping to think much about what that requires. Because we can quickly fill our fuel tanks almost anywhere. But when that many electric cars stop to charge at an autobahn filling station, I figure roughly 90 charging stations would be needed. That’s good news for Starbucks, at least.


Mr. Pint, are you more optimistic?

Pint: I maintain that some day we will be charging at home with AC electrical current from a wall socket. Recharging during a trip will then be necessary only when we drive long distances. And most of us rarely drive more than 300 kilometers. So those would be the only situations where I would need fast charging with direct current. Considering the scale of our economy, providing this infrastructure is really something we should be able to do.


For customers, enjoying the drive is also a key factor. This is where electric cars can excel, since unlike a combustion engine that first has to be revved up to a certain engine speed, all the power of the electric motor is immediately available when accelerating.

Bargende: I basically agree. The acceleration of a Tesla Model S, for example, is very impressive, so you don’t have to sacrifice any driving pleasure. But critics have pointed out that the service life of the battery suffers in correlation to how often the driver fully accelerates.

Pint: The Audi e-tron quattro concept, which Audi will introduce as a production model in 2018, will offer more in that respect. We are combining driving pleasure with long-range capacity, and with a range of over 500 kilometers (310.7 mi), our new model will be entirely suitable for everyday use. The Audi e-tron quattro concept will be powered by three electric motors. This will enable us to boost the car’s dynamism to a new level when cornering. That’s pure driving enjoyment.


A survey of Audi employees indicates they are very confident in the chances of future success with purely electric drives and the fuel cell. So Audi employees don’t share your doubts about electric cars, Mr. Bargende.

Bargende: Just the opposite is true: Your employees couldn’t be more ambivalent about this. All you need to do is add up all of the possible survey response options regarding combustion engines, and then see how they balance out with those for battery-powered cars or the fuel cell.


So you’re saying that a complete elimination of the combustion engine is not a viable approach. Does that mean we need synthetic fuels – such as Audi e-gas, for example – if we want to reduce CO2 emissions?

Bargende: Synthetic fuels are the most honest solution, provided they are produced from renewable energy sources. But these synthetic fuels are truly CO2-neutral only if carbon is removed from the atmosphere during their production.

Pint: I believe synthetic fuels can complement our mix of drive types. If we capture CO2 from the atmosphere during fuel production, I think the combustion engine still has a future for the long term.


How is automotive mobility developing now?

Bargende: We will see a continuing modest increase in the share of diesel use. There is hardly any other way to achieve the CO2 targets. After all, the world wants more cars. And this, of course, is where the electric car is advancing most rapidly, comparatively speaking. In absolute terms, however, until 2025 it will account for a percentage share in the single-digit range.

Pint: I am sure that the time is ripe for the electric drive system. Not only because there has been such progress with the battery technology and with getting the costs under control – but also because the electric drive is ideally suited for piloted driving and digitalization.


In all honesty, now. Is the electric car the panacea for our problems?

Bargende: There are many different desires and needs in the world. An automaker has to satisfy all of them, and therefore move forward with many developments simultaneously. Maybe striving for the “golden key” that opens all doors is the wrong approach. Maybe we simply need a variety of solutions.

Pint: Digitalization, connectivity and above all piloted driving are going to radically change what people demand in terms of safety, comfort and how they use their time. And what could be better suited for that than the convenient electric drive, which is also easy to control when in piloted driving mode? I am convinced we are about to experience the greatest change since the invention of the automobile. And the electric drive is playing a leading role in this.