BMW's Gas/H2 "hybrid" Car

Unlike GM's hydrogen (H2) fuel cell technology, as discussed at http://priuschat.com/index.php?showtopic=24842, BMW's initiative uses liquid H2 powering a dual fuel internal combustion engine, reducing the size of the storage tanks and allowing the driver to use either gasoline or H2 to power the car.

BMW is testing two of the cars near California's Port Hueneme, the deep water port where about a third of their cars entering the US arrive, at their Oxnard Test Center. The full story on the car is found at http://www.venturacountystar.com/vcs/busin...5017478,00.html

California has the "Hydrogen Highway" initiative, with a planned 300 H2 powered cars on the highway by the end of 2007. So far, 137 H2 fuel cell cars are driving here, and the two BMW hybrid Gas/H2 add to that number. The plan in California is to provide a series of hydrogen filling stations along the major freeways, although the BMW initiative appears to require a different type of H2 than the fuel cell cars. For BMW's liquid H2, only two filling stations exist, one in Port Hueneme and one in Washington, DC.

The advantages of liquid H2 in a hybrid Gas/H2 design are cited as a higher energy density than H2 gas, the relatively easy conversion of existing ICE to hybrid Gas/H2 use, and anticipated consumer acceptance since either readily available gasoline or the new fangled H2 can be used. However, combustion of liquid H2 is still a "dirty" process because the hydrogen is burned, and some attention has to be paid to emissions. The article did not mention if the hybrid Gas/H2 engine is a zero emission vehicle.

 

<div class='quotetop'>QUOTE(LaughingMan @ Sep 24 2006, 10:49 AM) [snapback]324323[/snapback]</div>

Not sure on that one ... the article is more of a "puff" piece, and there's no real analysis in it. They do have a picture of a rather unwieldy nozzle with a locking mechanism on it that looks like its 2 1/2" in diameter on the H2 fuel pump.

The tanks are said to be smaller, and located behind the rear seats making a slightly smaller trunk. Smaller tank size for the same energy content was one of the advantages cited by BMW over H2 gas.

 

<div class='quotetop'>QUOTE(clett @ Sep 25 2006, 01:46 AM) [snapback]324566[/snapback]</div>

That link also has some good info on NOx emissions ... which you get any time you heat metal up. So even though burning the hydrogen doesn't have CO2 emissions directly (although making the hydrogen does, as you point out), the car is not "clean" in terms of NOx, which is another greenhouse gas.