Globe and Mail: Versatile Hydrogen 7 blends two systems

MUNICH

BMW officials say the 260-horsepower Hydrogen 7 is “autobahn fast” and it certainly seems so from behind the wheel. But this is what you would expect from a luxury sedan powered by a 6.0-litre V-12 engine.

The surprise is what comes out of the tailpipe: essentially nothing. Hydrogen 7 emissions are cleaner than the air you breathe.

A hydrogen car? It’s real and it’s here. BMW won’t discuss the cost of the 50 Hydrogen 7 cars it is now putting on the road, or how much it spent to develop them. But it is safe to say the one I am now driving is valued at hundreds of thousands of dollars.

The technology in the Hydrogen 7 and the very philosophy behind it – what BMW calls “Efficient Dynamics” – is very real, though, despite the price. So real, in fact, that BMW plans to put a small fleet of these hydrogen-powered 760Li cars on North American roads this year.
The idea is to gather real-world feedback about the Hydrogen 7 from selected consumers, opinion leaders, politicians and the like. They will drive the car for free starting this year. Each will take a Hydrogen 7 for periods ranging from four weeks to four months.

In markets where a liquid hydrogen fuelling station is not available – and there are only two such filling stations in North America, one in Washington, D.C., the other in Los Angeles, and perhaps a few dozen in the rest of the world – the cars will be fuelled at BMW’s mobile hydrogen fuelling stations.

BMW officials insist that their Hydrogen 7 is nothing less than an environmental-friendly luxury sedan that also is a joy to drive.

The bi-fuel Hydrogen 7 is in essence a BMW 760i that, at the push of a button mounted on the steering wheel, is capable of alternating between gasoline and liquid hydrogen. The heart of it all is an internal-combustion engine that runs on liquid hydrogen or gasoline.

The car itself? The Hydrogen 7 looks exactly like a standard 7-Series, aside from three small “Hydrogen” nameplates. Also, a small opening on the hood allows hydrogen vapours to escape.

In hydrogen mode, the 260-hp engine runs a bit louder, but even this is barely noticeable. What matters is that, from a driving dynamics point of view, there is no perceptible lag when the engine switches from gasoline to hydrogen.

Unfortunately, during our test drive the dual-fuel system temporarily fails, leaving us planted at the side of the road for a few brief moments. Eventually, the 7 starts up but from then on will run only in gasoline mode.

Still, there is smart engineering at work here. Unlike some auto makers, who are promising futuristic fuel cell systems, BMW has chosen to focus on using hydrogen to power a relatively conventional internal combustion engine.

By going bi-fuel with the Hydrogen 7, a buyer would be able to run on conventional gasoline when unable to find a hydrogen pump. A car capable of running on both gasoline and hydrogen is a more practical solution in a world where the development of a hydrogen-refuelling infrastructure is not yet even in its infancy.

The Hydrogen 7 is the latest and purest expression of what the BMW Group’s drivetrain development division calls “Efficient Dynamics.”

Professor Burkhard Goschel, head of development at BMW, says Efficient Dynamics is a philosophical approach that “resolves the apparent conflict between reducing consumption and emissions on the one hand and enhancing performance and agility on the other.”

In truth, Efficient Dynamics is what might be called a “big picture” approach to powering vehicles.

It means that the seemingly incompatible issues of environmental compatibility and consumption are resolved not in isolation from each other, but together and in the larger context of legal and statutory requirements, social acceptance and customer demands.

“Not everything that is technically feasible is also economical and ecological,” Prof. Goschel says. “And, most importantly, it doesn’t necessarily convince the customer. An intelligent drive where power can be called up at any time and which provides more spontaneity for less consumption is a realistic development proposition.”

The Hydrogen 7 has a range of about 200 kilometres on hydrogen and an additional 500 km on gasoline. A 30-millimetre-thick, 200-kilogram cryogenic fuel tank holds 170 litres of liquid hydrogen at minus 254 degrees Celsius. BMW says the insulation is equivalent to the thickness of 17 metres of Styrofoam.

One compromise here is the large tank. It uses half of the trunk space. Rear seats are moved up 114 mm to accommodate the tank. Expected advances in tank technology will resolve these issues over time.

Another ingenious development is the BMW-developed coupling system that allows the car to be filled with liquid hydrogen at a conventional filling station with fuel stored in above-ground tanks. The on-board tank can be filled in eight minutes and is designed to keep hydrogen cold for up to 17 hours. After that, it safely vents away as water vapour

JEREMY CATO
Globe and Mail Update