BMW Hydrogen 7: Up a creek without the pump

BMW think that hydrogen is the fuel of the future. But is it all just gas, asks Sean O'Grady

Some cars are so exclusive that you have to be invited to purchase one. And rather like an invitation to receive a knighthood, the answer you will give is usually known in advance. The last car to enjoy such status was the Ferrari Enzo, arguably the most remarkable and profligate supercar ever created. Now comes an even more exclusive vehicle that could equally be regarded as a green supercar; the BMW Hydrogen 7.

In fact, BMW won't let anyone buy this car. Should you fit into their criteria as an ambassador for greener motoring then you will be allowed to trial one for a time, but it will remain the property of BMW. Ferrari let you keep your Enzo.

So what is it that makes this car so special? Well, it's the future. Or at least it's BMW's version of the future, and a very peculiar one, too. Most of the world's car companies are betting the ranch on petrol/electric hybrids or the hydrogen fuel cell. This BMW runs on hydrogen too, of course, but it simply uses it as a substitute for petrol. The hydrogen fuel cell, as it is being developed by the likes of Honda and Mercedes-Benz, effectively replaces the internal combustion engine, with the motive power being generated via electric motors. As it happens, the Hydrogen 7 will still run on petrol, too. Which is just as well, for running the car purely on hydrogen would be a bit of a headache.

Through no fault of BMW, it has to be said, the world is not quite ready for their latest product, thoroughly engineered though it is. First, there are only about six hydrogen fuel stations in the world, so you might easily find yourself out of juice , especially when you discover the Hydrogen 7 only has a range of about 125 miles. (You can go a further 310 miles in conventional petrol mode.) There's one in Hornchurch, Essex apparently, which may close, but one way or another there should be one somewhere in the UK, probably London, next year.

BMW tell you not to park your Hydrogen 7 in an enclosed car park. Here's the official reason: "Since adequate statistically reliable data obtained under regular operating conditions is not yet available to confirm the safety of the hydrogen tank as such, parking in closed-in spaces is currently not allowed." Presumably it might be tricky to get it on a ferry, then. You might not be able to take it on the Channel tunnel either, but, then again, it's illegal to use the Hydrogen 7 in France.

What else? Well, the hydrogen fuel will evaporate if the car is left standing for long, with half of your precious hydrogen gone in nine days. Precious it is too, at something like the equivalent of £7.50 a gallon or 150p a litre. You see, the fuel tank isn't pressurised but merely insulated. Like a vacuum flask, it will keep it warm but not forever, at minus 253C with not too much evaporation, but it will certainly "boil off" if it isn't burned in the engine. Be prepared for a wait at the pump; it takes eight minutes to fill up with hydrogen.

The real problem with the tank is the space it takes up; it reduces legroom back to that of the normal wheel base model. You also lose half the boot, though BMW say you can still get two golf bags in the back, so that should placate their target market at least.

How green is it? Well, that's tricky. Running on hydrogen, it produces no emissions from the tail-pipe, so local pollution is eradicated. The real problem is the energy used to make the hydrogen: if it has come from natural gas, then the green benefits are greatly diminished; if it is via electrolysing of water powered by renewables such as solar power, things are transformed (but such energy is expensive).

Yet all those objections aside, it is a technical tour de force. Driving the car you'll feel little practical difference. You can notice the extra weight and the engine is definitely noisier when burning hydrogen. (All the Hydrogen 7's will be left- hand drive, by the way.) Apart from that it's very much like any 6-litre V12 BMW 7-series: lagging behind the new Mercedes-Benz S-Class in safety features and refinement, less meticulously finished than an Audi A8 and less warm and welcoming than a Jaguar XJ, but a perfectly acceptable set of wheels for the rich and famous.