One of the best reasons to be at a big motor show on its opening day is to watch some of the car business's oldest rivalries simmer and develop – to observe as Ford and GM frantically try to outdo each other in Detroit's Cobo Arena, to follow Ferrari's top brass as they tour the Porsche and Lamborghini stands at Geneva.
The Frankfurt show is notorious for its overblown excess and one-upmanship. Keen to show a strong hand on their home turf, Germany's three premium automotive brands – BMW, Audi and Mercedes-Benz – always compete to have the biggest stand crammed with the most new cars and the most headline-making concepts. This year's Mercedes stand took four months to put together; BMW's actually has a road built into it.
And this year the battle between Germany's “premium three” took a particularly interesting turn. Each of them made a battery-powered sports car one of their main attractions. At 8:30 a.m. on the Frankfurt show's opening day, BMW unveiled the Vision Efficient Dynamics concept, an ultra-sophisticated hybrid-electric sports coupe which we previewed last month. At 10:30, Mercedes announced that it would be building an electric version of the new SLS AMG supercar. And just before noon Audi took the covers off the e-tron, ostensibly a battery-powered R8. So how do they differ, and is it purely coincidence that they all came along at once?
FIRST UP, AUDI
It's the second day at Frankfurt. We're off to the Audi stand first to see the e-tron. Some say it's a teaser for a smaller Audi sports car – an “R4” if you like – based on a new shared VW Group platform. But that's not the line we get from Thomas Krauter, Audi's head of concept and prototype development and the man who was also in charge of building the diesel-engined R8 V12 concept car.
“The V12 diesel R8 project was canceled last year and we started on the e-tron at the very beginning of 2009, always with Frankfurt in mind,” he says. “It's a shorter car than the regular R8 but looks largely the same. It's built in the same way, based on the same aluminum spaceframe structure, and it has the same track widths. The reason that it's slightly shorter is because the [smaller] electric powertrain allowed us to adapt the packaging.”
The e-tron is powered by a 53kWh lithium ion battery pack, which sends power to all four wheels via four independent electric motors that each produce 78hp and 830lb ft of torque. This gives the car 313hp and an incredible 3319lb ft. The batteries sit immediately behind the passenger compartment, where the engine would be, and the motors in pairs in line with each axle and along the car's centre line.
Each pair of motors has its own gearbox and cooling system. Audi claims the car can crack 62mph in 4.8sec and get from 37-75mph in just 4.1sec. Its top speed is limited to 124mph. “It would go on to about 160mph unlimited, but traveling at those speeds takes too much power out of the battery too quickly,” Krauter says.
It's a proper quattro, too, of course. “The independent motors mean that we can vector torque asymmetrically much more quickly and easily than we can with a conventional powertrain,” Krauter says. “So during cornering you can immediately send pulses of power to the inside or outside wheels when the ESP system detects under or oversteer. It has a really unbelievable effect on the car's cornering potential.”
So will Audi build it? “A three-year development project for this car, part-funded by the German government, has just been announced, and there will be a small production run at the end of it,” Krauter says. “I don't know how many cars we will make, or whether they will be sold or leased. But it will be exciting to find out.”
NEXT STOP, MERCEDES
From one all-electric supercar, we take the short walk to Mercedes' “Forum” to see another: the SLS EV. Merc's show stand is enormous – a whole hall full of cars – and right at the back of it is the SLS, surrounded by interested media people.
The car on show is the V8 gasoline-powered one, though. Another SLS sits on a turntable at the opposite end of the stand, but that's a gas, too. There's no sign of the battery car at all – until we turn around and take a look at a display of the SLS's gas powertrain. A video screen behind it flashes up details of the electric car: 2013 launch date, for lease only, 125-mile range and 150mph top speed. Yet still there's no car to look at. Seems odd. Smacks of a last-minute change of plan, in fact. So was Mercedes' hand forced into announcing the car early in order to compete with Audi and BMW?
We track down a Mercedes spokesman, who confirms there's no electric SLS on show. “It was never meant to be here,” he says, tacitly confirming our suspicions. “But it'll look exactly like the regular SLS. The car was designed from the outset to take both gasoline and electric drivetrains.”
Some of the components and control electronics for the SLS EV have come via Tesla, our man says, after Mercedes bought a minority stake in the firm earlier this year. The car's motors will rev to 11,000rpm and each one produces 131bhp and 162lb ft of torque. Like the Audi, there will be one for each wheel, which gives the car a theoretical 524hp maximum and potentially 648lb ft.
The motors, gearboxes and inverters weigh 151kg per axle, and the car's 48kWh lithium ion battery pack – oriented in a T shape in and around the car's transmission tunnel – weighs 705lbs. “So yes, the battery-powered SLS will be slightly heavier than the regular one,” says our guide. “The target is for 62mph in about five seconds.”
Why make it? “Because AMG, like everyone, is under pressure to bring its carbon emissions down,” he tells us. “We have a plan to make a 30 percent reduction by 2012 and further progress after that with this car, and with hybrid versions of some of our other cars.”
MEANWHILE, AT BMW
Finally, we take the long walk to BMW's hall, at the farthest end of the show. We find the Vision ED concept in one corner of it, in front of an enormous show stand amphitheater. The car is every bit as arresting to look at as it is in photos, and it's more striking than the Audi because of its imaginative design and blazing color scheme.
Beside the car, we meet BMW chief exterior designer Anders Warming, who runs through its sophisticated powertrain and active aerodynamics. So what sets it apart from the many other EVs at Frankfurt this week? “Well, it's a hybrid, not a full EV,” he says. “We're using this car to showcase our very latest Efficient Dynamics technology, so it's got a 1.5-liter, 161hp, 214lb ft turbodiesel engine in the front, driving the rear wheels. But it also has an electric motor on each axle, which together can add as much as 210hp and 376lb ft.”
Overall, the Vision ED isn't completely zero emissions; BMW quotes 99g/km for it and a typical 76mpg. But it is a plug-in hybrid and does have a 35-mile battery-only range, so you could probably do your daily commute without burning any fossil fuel (assuming the electricity that charges it comes from a suitable source). Over and above that, it'll run for 400 miles on diesel power, which makes it more suitable to current refueling networks, Warming says.
“The exhaust heat recovery generator on the car is a breakthrough for us, too,” he adds. “That can capture up to 200 watts of heat energy at a time and flow it back into the car's lithium-polymer batteries.”
Having seen the Audi e-tron and at least read about the Mercedes SLS EV, it's the BMW Vision ED that leaves the most lasting impression. Out in the real world, the BMW would be the most usable of the three sports cars and it seems to be packed with the most sophisticated technology. It's also such a striking design and seems to be more than just a zero-emissions publicity stunt. This “layered surfacing” design, says Warming, shows how the next generation of BMW cars will look.
So is it just a show pony, or will we be able to buy one? Work on BMW's low-emissions flagship supercar, the Z10 ED, is ongoing, or so the rumors suggest, and if the Vision ED does nothing else, it provides a big hint about what to expect from that car.
“This is not just a styling exercise,” says Warming. “It's a fully feasible and sustainable BMW sports car. The executive board really like it. And I, for one, think it would look even better on the road.”