Hydrogen hybrids represent a giant step beyond even the significant fuel economy advantage of fuel-electric hybrids. For one, hydrogen fuel cells hold out the promise of greatly reducing dependence on fossil fuels. Even more remarkable is the promise of slashing net emission of greenhouse gases since the “exhaust” from fuel cell cars consists chiefly of water.
Honda has already released two FCX hydrogen hybrid “stock” units on lease to individuals. Nonetheless, the company confides that it is undertaking serious efforts to bring up power, mileage and fuel efficiency. The goal for the 2008-model FCX is at least 100 MPH top speed and 68 MPG equivalent in federal city-highway combined-driving cycle for gasoline engines. This is about double the performance of the most fuel-efficient U.S. 2006 model (the Ford Escape Hybrid: 36 mpg city / 31 mpg highway) but little better than the most thrifty Japanese model (Honda’s own Insight: 60 mpg city / 66 mpg highway).
The technology continues to evolve. Affordability aside, some carmakers are hedging their bets by developing hydrogen combustion and fuel cell power trains side by side. And there are technical hurdles having to do with the low volumetric energy of hydrogen vis-à-vis gasoline, sluggish load change, high cost and emissions penalty of production, setting up a distribution infrastructure, and uncertainties about service life.
Nonetheless, Honda’s peers are just as gung ho. BMW produced no less than 100 internal combustion Hydrogen 7 units and sent them off for test drives by media, government officials and other opinion leaders in a campaign to gain support for hydrogen hybrid R & D. Mazda bet on hydrogen-burning rotary Wankels. DaimlerChrysler has the F-Cell, a fuel cell variant of the Mercedes-Benz A-Class. Ford launched the Focus FCV, a fuel cell modification of the Ford Focus, late last year.
Technological hurdles aside, Honda demonstrates its confidence in fuel cell hybrids by making the FCX available for test drives and going into production with even more fuel-efficient versions of the sedan sometime in 2008.