BMW Hydrogen 7 - Behind the wheel

During my visit to the LA Auto Show, I was fortunate enough to drive a hydrogen-powered BMW 7 Series. Unlike hydrogen-powered fuel-cell vehicles, it uses the hydrogen to power its regular internal-combustion engine.

The hydrogen solution is still debatable, but it is considered by many to be the ultimate clean fuel since it uses a widely available resource. And despite division over the merits of hydrogen, most automobile companies are betting on it in one form or another. Even a casual stroll of shows this season it is clear that automakers are investing serious engineering resources and money into developing hydrogen-powered test vehicles.

First impressions
The Hydrogen 7 is hybrid/flex-fuel/bi-fuel car that can run on both hydrogen and gasoline. This switch can be done on the fly by simply pushing a button on the steering wheel. Otherwise, the cabin is very similar to the regular 7 Series. Trunk space is very limited (smaller even than in a 3 Series) and acceleration seems a bit lethargic. Another noticeable difference was a slight pinging at low speeds when using hydrogen. The car always starts consuming hydrogen and once the catalysts are up to working temperature, the car can then be switched over to gasoline without any noticeable hesitation. The 6.0-liter V12 engine produces only 265 hp and 287 ft-lb of torque, which is not much for a vehicle that weighs about 5,000 pounds. Those figures explain the rather slow takeoff and the effort needed to merges in to traffic. The Hydrogen 7's performance is a stark contrast to typical BMWs, which have long been known for their wonderfully smooth and powerful engines. On the plus side, the car itself is quiet and drives adequately in dense traffic.

The 8 kgs of hydrogen is kept in liquid form in a tank just behind the rear seat. That amount yields a range of around 120 miles. Unlike the current group of hydrogen-powered fuel-cell vehicles—which store their hydrogen in a compressed form at 5,000 or 10,000 psi—the Hydrogen 7 holds its hydrogen in a liquid state at -253 degrees Celsius (-423 degrees Fahrenheit). Unfortunately, even with its double-walled tanks and insulation, the hydrogen slowly evaporates. And if the car remains parked for 10 to 12 days, the hydrogen is completely depleted. When running on hydrogen, the emissions are mainly water, although there are traces of CO2 and NOX as a result of burning engine lubricants.

One unforeseen issue I had with the car during my stint with it was the inability to park it inside a garage. The BMW representative insisted that the vehicle had to be parked outdoors at all times. This became the subject of many interesting conversations with parking valets, who were intrigued by the technology but were worried about being part of another Hindenburg tragedy.

Refueling with liquid hydrogen is the biggest challenge when driving the car. After all, where does the liquid hydrogen come from and where are the filling stations? These same issues affect fuel-cell vehicles, as well. Currently, most hydrogen is obtained from natural gas but it can also be generated from splitting water using renewable electric energy. 

In sum, the Hydrogen 7 has some drawbacks, including a small trunk and not being able to park in a garage. However, it allows the flexibility of using hydrogen (when/where it's available) or gasoline. Likely, we'll have to wait decades for a hydrogen infrastructure to catch up to the petroleum-based transportation system, which also applies to a lesser extent to electric vehicles. Plus, we can add these drawbacks to the list of other negatives:

• The prohibitive cost of developing the technology and the vehicles.
• Skeptic public with potentially explosive and unfamiliar fuel.
• Lack of fueling infrastructure and production obstacles.

Still, these are similar to the hurdles early automobiles had to deal with at the dawn of the 20th century. Back then, the horse was king, roads were little more the dirt cart tracks, and there were no gas stations or oil companies. A major difference is that today's cars are really good when compared to a horse and the current alternatives are not quite there yet. BMW's approach may be an interesting interim solution between a hydrogen-powered world and the current oil-based transportation system.

Final thoughts:
I used to live in the LA area before moving to Connecticut, and I had almost forgotten the vast volume of traffic that is constantly moving around the LA freeways. At lunch time on a Saturday morning, I was struck in stop-and-go traffic, seven lanes wide (no car pool lane) for no apparent reason except for just an extreme volume of vehicles. Now, I love cars -- probably more than most people -- but it struck me that even if everyone was driving a hydrogen-powered fuel-cell vehicle, this volume of stationary cars is such a waste of time and energy, regardless of whether or not the energy is renewable. It goes against my grain to say it, but something must be done in the future to expand telecommuting, public mass transit, or other ways to reduce congestion. Simply building wider freeways is not a responsible option.

—David Champion

Also read:
Want to lease a fuel-cell car?
The Honda approach to fuel cells
How the fuel-cell cars compare

Comments

[Vic]

I think that this is the way to go for the long run, but for now auto makers should try to make gas engines more efficient.

[Andrew Lewis]

I completely disagree with David Champion on the thought or notion that building wider freeways is not a responsible action. You have to remember that this is the USA and thinking that something can be done to move USA citizens on to a mass transit system is too idealistic and hence too far fetched. You can see this for your self by observing a timeline of survey plats and maps of america's urban centers, and observe the "spreading" urban sprawl trend that was set back in the 1950's by corporations and the trend continues today. We can curb this trend but it is far to late to stop the trend. Americans want the convenience of choice, to be able to choose to stop at the grocery store (eg Walmart...which could set us on a whole new tangent...) to buy household necesities and food for the kids on the way home from work. You do not have that option on a train or bus.
We must develop a strategy to increase the capacity of the freeway system in our urban centers and at the same time increase the efficiency of petroleum powered vehicles while continuing to fund Fuel Cell research. This way we can merge these efforts to provide a large overall improvement in environment protection. I suggest to read another response i have posted at this link:

http://www.deez.info/sengelha/blog/2007/02/21/chicago-crosstown-expressway/

i am a civil engineer, i do this professionally, remember less congestion on freeways equals less gas consumption and emmissions, which means it will be necessary to widen certain freeways and improve various freeway networks.

Andrew Lewis

[J.Q. SMYTHE]

I am a great lover of vintage American cars , and the freedoms that automobiles afford us. However,I agree with the authors position on aleiviating gridlock on American highways thru incentives to tele-commute and sustained and committed devolopment of public transportation.
To the blogger who argues that the trend towards urban sprawl is inevitable seems to be , simultaneously, a defeatist and flat earth point of view.None of mankinds great achievements were realised by belief that they were impossible.Amercians have an amazing ability to embrace trends,and if you don't believe that try finding a new 3 piece double knit polyester liesure suit at your local Wal-mart.

[Pat]

Gooid to see BMW and Honda are making the move to push this technology aas fuel prices are way too high and don;t look like leveling out.

[Joe]

With the improvement in the quality of strong lightweight meterials, wouldn't it be better to put a second tier of roadway over the standing roadways rather than widen them?
Doing that would be something to think about and the engineers to ponder.

[Anthony Inbody]

They need to remove all tolls that require people, without electronic passes, to stop. It would not be to diffucult to make it an online thing kind of like in the same way they take a picture and send you the ticket for running red lights or speeding. It congests the roadways when 1/2 the people have to go from 70 to zero every ten miles, plus it would slightly reduce gasoline usage. in another 50 years we wont drive ourselves, sensors and computers will, unfortunate however more efficient. this will allow for higher speeds,reduce the distance between cars and elimnate the need for stoplights. i saw this thing on the discovery chanel about how thousands of grasshopers fly within centimeters of each other and never collide.there studying them to gain more understanding for practical use.