Will Hydrogen Fuel Really Work?

Futuristic cars powered by cleaner-than-clean hydrogen fuel cells have been touted by voices as diverse as left-leaning economist Jeremy Rifkin, the founders of the Rocky Mountain Institute, leaner-than-lean Governator Arnold Schwarzenegger, and decidedly right-leaning decider President George W. Bush.

All have praised the potential of hydrogen fuel cells—which leave just a trickle of water as their only combustion byproduct—to replace today's fossil-fuel swigging, greenhouse-gas belching automobiles.

But here's the snag. Although hydrogen is indeed the most abundant element in the universe, most of it can't be used as fuel because it is locked tight to other elements as molecules. Pure hydrogen is produced by applying high-heat (which takes a lot of energy to produce) to natural gas (that's right, a fossil fuel) or, less often, to gasoline or coal (fossil fuel, fossil fuel). Worse yet, this “cracking,” or “steam reforming,” process releases carbon dioxide, a greenhouse gas.

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