NEW YORK -- Hybrid cars, which combine electric motors with small petroleum engines, will outpace the environmental benefits of hydrogen fuel cell cars until at least 2020, according to a university study.
Hydrogen fuel-cell vehicles have low emissions and energy use on the road, but converting a hydrocarbon fuel such as natural gas or gasoline into hydrogen to fuel such vehicles uses substantial energy and emits greenhouse gases, the study said.
The Massachusetts Institute of Technology study was published after the Bush administration announced in January an initiative to develop hydrogen fuel cells. Combined with last year's government-industry "Freedom Car" program to build vehicles fueled by hydrogen, the initiative will be powered by $1.2 billion in government funds.
Energy Secretary Spencer Abraham said in January it should be cost-effective to produce hydrogen-fuel cars in large numbers and have them in showrooms by 2020.
The cars could reduce U.S. demand for foreign oil by 11 million barrels per day by 2040, according to the Energy Department.
But even with aggressive research, a hydrogen fuel-cell vehicle would not be better than a diesel hybrid in terms of total energy use and greenhouse gas emissions by 2020, the study said.
That's because virtually all industrial hydrogen supply at the moment comes from natural gas. In the future, analysts say, large amounts of hydrogen will be separated from water, where it bonds with oxygen, through the use of alternative energies like wind and solar power.
But for now, the green method of making hydrogen is too expensive, according to the study. "If we learn how to do it, I think that's absolutely wonderful, but I wouldn't hold my breath," said Malcolm Weiss, a researcher with MIT's Laboratory for Energy and Environment.
"Ignoring the emissions and energy use involved in making and delivering the fuel and manufacturing the vehicle gives a misleading impression," he said.
Beyond 2020, hydrogen cars will win out, predicted the researchers, who do not recommend stopping work on the hydrogen fuel cell. "If auto systems with significantly lower greenhouse gas emissions are required in, say, 30 to 50 years, hydrogen is the only major fuel option identified to date," said John Heywood, an MIT researcher.
That hydrogen would have to be produced without making greenhouse gas emissions, through a non-carbon source such as solar energy, or from conventional fuels while sequestering the carbon emissions underground.
So far, Japan's Honda Motor Co. Ltd. and Toyota Motor Corp. are the leading makers of hybrid automobiles. Hybrids have fossil fuel engines that work alternatively or in concert with electric motors to reduce smog emissions and increase fuel economy, without ever having to be plugged in.