VW powertrain chief expresses electric doubts
BY JAMES STANFORD | 5th Oct 2009
While Audi’s bold e-tron supercar and Volkswagen E-Up! electric cars were presented at last month’s Frankfurt motor show with production promised from 2012 and 2013 respectively, the man in charge of Volkswagen Group engine and transmission policy is yet to be convinced that electric vehicles will be used for much more than short-range transport in mega-cities for the foreseeable future.
Wolfgang Hatz, the cigar-smoking head of Volkswagen Group powertrain management who drives a V10 Lamborghini Gallardo and twin-turbo V10 Audi RS6, told GoAuto of his doubts about electric vehicles which run from energy storage to price and range.
Mr Hatz stipulated that although great progress has been made with battery technology recently, especially the development of lithium ion, it had not advanced enough.
“If you look at the energy stored in a fuel tank compared to a battery, the relationship is very bad,” he said.
“Today you can say 1kg of fuel is equivalent to 100kg of batteries of energy and this is a problem. OK, you say that then we have the efficiency of the petrol motor and on the other hand the efficiency of an electric motor is very high, but if you look at the total chain, producing the electric power then the efficiency drops.” Energy storage continues to be a major issue, said Mr Hatz.
“The problem is that the energy we can store in the battery is too low. The volume is too big and it is too heavy,” he said.
Mr Hatz added that pricing was also a major issue for electric powertrains.
“The problem at the moment is the very high cost, especially for the battery but also for the components. I think at the moment this will be prohibitive,” he said.
Asked if a technology breakthrough would be needed for electric propulsion to take off, Mr Hatz said: “We wait for the breakthrough for long years, we will now start with the lithium ion batteries. This is a big step forward and they have moved forward a lot in the last few years.” Mr Hatz said technology advances were not as quick as car-makers had hoped.
“Now everybody is pushing, we have to develop new battery technology, but we when we talk to new research people, they talk about 2030 and (even) then the step is not as big as we expect, so we have to be realistic,” he said.
Mr Hatz is still confident there will be a role for small electric cars, such as the VW e-Up! in certain circumstances.
“This technology will come up, especially in mega-cities,” he said. “Downtown it can be a solution for people who have a relatively short driving range can be a viable solution.
“But it is not a solution for going from Brisbane to Melbourne.” Mr Hatz doubted electric vehicles would be capable of serious load carrying or long distances.
“There are some things I can’t see we will have,” he said. “An SUV, a pick-up, which has to tow three and a half tonnes for 800km – that I can’t see. For that we would need completely different battery technology.” Mr Hatz made it clear that turbo diesel and direct-injection turbo petrol engines would remain the dominant powertrain solutions within the Volkswagen Group for some time.
Hybrid cars will come, including next year’s Audi Q5 hybrid, VW Toureg hybrid and Porsche Cayenne hybrid, but Mr Hatz said hybrids would only be used on premium models.
“Looking at this as an engineer it (hybrid) is an engine that is right for city driving, if you go long distances the advantages become smaller and smaller,” he said.
“I believe that on those cars TDI technology is a very competitive solution in the relationship between what is the cost and the benefit you gain. On the other hand I believe very strongly that we have to work to reduce cost on those components.
“I’m sure that at a certain segment it may become a higher volume, in lower (cost) segments I believe it is a very expensive way to save fuel.” The head of Audi’s Aluminium and Lightweight Design Centre in Neckarsulm, Heinrich Timm, is more forthright in his personal view of hybrid technology which adds considerable weight to vehicles.
“I don’t see hybrid as the future,” he said.
Mr Timm agreed with Mr Hatz’s view that the weight of electric vehicle batteries will be a problem.
“In order for our cars to get an acceptable range, they need a lot of battery capacity and that means weight,” he said.
While Audi has already developed a range of weight saving techniques such as the use of aluminium space frames and other lightweight materials, electric vehicles will require even more weight to be shed.
“We have a strategy in Audi, especially with new and alternative engines, electric and hybrid, we have to focus on the lightweight solutions more than we did up until now,” said Mr Timm.