Reviews and Road Tests
First Drive: BMW Hydrogen 7
By Bryan Joslin, photos by George Achorn
May 10, 2007, 12:45

I started reading car magazines in the late Seventies, in the thick of the doom-and-gloom days of the car industry. Everyone then was predicting the end of enjoyable driving and “fun” cars, as new emissions requirements were sapping the life out of everything. Back then, even a Corvette with a 5.7-liter V8 produced a mere 230 horsepower. The future, indeed, did not look promising, but technology eventually overcame those challenges. Today’s engines are capable of producing that same power with half the displacement, twice the economy, and virtually no pollution.

We find ourselves at a similar watershed today, only this time we’re not only looking to reduce pollution but also our dependence on fossil fuels. The goal is to eventually produce vehicles that generate no harmful emissions while operating on a renewable fuel source, and for that reason companies like BMW are looking to hydrogen as the solution. The reasons are simple- hydrogen is the most common element on the planet, and when it combusts, the only exhaust is water. But hydrogen represents its own challenges, not the least of which are separating it from other elements, storing it and establishing a commercial infrastructure.

Not so much a challenge as an unknown is how hydrogen will actually be utilized for personal transportation, with common wisdom leaning toward eventual electric cars powered by hydrogen fuel cells. But that technology is years, perhaps decades, off. On top of that, it doesn’t promise to be the type of driving experience today’s enthusiasts will be longing for.

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Fortunately, BMW is taking a first step into the hydrogen future with its Hydrogen 7 cars. Based on production 7 Series sedans, these prototypes employ conventional internal-combustion engines converted for operation on either liquid hydrogen or conventional gasoline. This approach not only uses available technology (speeding the advance of hydrogen generation, storage, and infrastructure), it also delivers a dynamic experience familiar to today’s drivers, especially those who already drive BMWs.

Although there is just a handful of Hydrogen 7’s in the country at the moment, they are actually considered production models. Some are in private hands, while others are being utilized institutionally. Among the lucky few who can be seen tooling around in a Hydrogen 7 is Governor Schwarzenegger of California. Despite our considerably lower profile, we were able to get some seat time in one of these Sevens recently and took it cruising through the bustling streets of Manhattan.



Aside from the reflective foil graphics on the exterior, there is almost nothing to give away the Hydrogen 7 as anything other than a your average, run-of-the-mill 760Li. Strip away the stickers and only the large hydrogen fuel filler port and modest bulge in the hood (to provide clearance for the hydrogen injection valves) distinguish it as something truly uncommon.

Even inside, there are no obtrusive screens, buttons or levers. The few unique controls are integrated into the steering wheel and dashboard as though BMW had already built 100,000 of them. The rear seating area gives up 4.5 inches of legroom compared to a conventional 760Li, making room for the 30-gallon hydrogen fuel tank between the back seats and the trunk. Otherwise, the cabin is sumptuously appointed with walnut and leather and Alcantara.

Starting this car is no different than starting any other BMW. By default, the Hydrogen 7 starts up under gasoline power. Once it reaches operating temperature, it can be switched over to hydrogen propulsion. The switchover is virtually seamless, handled at the mere pressing of the H2 button on the right side of the steering wheel. Other than a slight hiccup during the transition, which could be easily mistaken for a typical misfire, driving on hydrogen feels mostly like driving any other large BMW.



The Hydrogen 7 uses BMW’s 6.0-liter V12 engine as the basis. Pure hydrogen, however, is a different animal than gasoline, burning up to ten times faster than conventional fuels. Accordingly, the engine management system has been programmed to deal with the unique properties of liquid hydrogen, and the resulting output is lower than a normal gasoline V12. And in order to make the car’s performance more predictable, the engine delivers the same output in gasoline mode as it makes in H2 mode. The result is 260 hp at 5100 rpm and 287 lb-ft of torque at 4300 rpm.

Around town, it gets off the line like any other 7, but once under way it seems to lack the mid-range potency required to squirt safely through the last few amber rays of a rapidly-changing traffic light. Some of this is due to the weight- pulling over 5000 pounds of technology is a lot for just 260 horses these days. Nevertheless, BMW claims the Hydrogen 7 will get to 62 mph in nine and a half seconds and will pull to an electronically limited top speed of 143 mph.

Ride and handling are like pretty much any other full-tilt Seven. Aluminum is used extensively in the front suspension to keep weight down, but springs from BMW’s in-house Security 7 model help deal with the added mass that comes with having dual fueling systems.



Our time in BMW’s zeppelin was brief, but it made a significant impression. Suddenly the thought of dwindling fossil fuel supplies and reducing greenhouse gases isn’t sounding so bleak. Just as it did a quarter century ago, technology is overcoming the next major obstacle on the road to more responsible motoring.

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