The London Olympics now underway are a showcase for green cars.

Automotive sponsor BMW is getting massive exposure for 4,000 of its greenest vehicles, including lower-emission ActiveHybrid models, fuel-efficient diesels, and much-anticipated i3 all-electric city car and i8 plug-in hybrid sports coupe.

Londoners, Olympics visitors, and the global TV audience see glimpses of these vehicles whizzing along the special "Olympics lanes" that have been set aside on London's congested streets and highways to whisk athletes and dignitaries from place to place.

But one non-BMW initiative--a handful of London taxi cabs fueled on hydrogen--is turning out to be not quite as green as planned.

Due to the shutdown of a central hydrogen fueling station near the Olympic Arena east of central London, the hydrogen taxis have to be taken on a 130-mile round trip to a hydrogen fueling station operated by Honda in Swindon to be refueled.

And they make that trip on the back of flatbed diesel trucks.

Which likely negates any net carbon reduction benefits from their zero-emission operation.

Mazda Premacy Hydrogen RE Hybrid

Mazda Premacy Hydrogen RE Hybrid

HyTEC, which operates the five hydrogen taxis, hopes that a second, more central hydrogen fueling station will open at London's Heathrow Airport, west of central London, before the end of the Games.

Meanwhile, a fleet of buses also fueled by hydrogen has been affected by the closure as well.

To keep this all in perspective, the overall reduction in emissions from the various green Olympics vehicles is likely far less than that the reduction from Londoners simply staying out of their cars and reducing their vehicle travel in light of dire predictions of massive chaos, gridlock, traffic paralysis, and so forth.

But it does point out the importance of hydrogen fueling infrastructure, one of a number of challenges to widespread rollout of hydrogen as a vehicle fuel.


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