Last month, GM announced plans to distribute 100 fuel-cell-powered vehicles to customers next fall, along with plans to develop home-based hydrogen refueling stations. It’s the automaker’s latest move in its stated goal to build the world’s largest fuel-cell vehicle fleet. The first 100 vehicles will be available for evaluation in California, New York, and Washington, DC.
But, from an environmental and technical standpoint, does it make sense?
Fuel-cell vehicles, which are being developed by other automakers as well, are powered by electricity generated from hydrogen. They emit only water vapor from their tailpipes, and the fuel cells are significantly more efficient than an internal-combustion engine in extracting energy from the fuel.
But GM’s focus on creating a fleet of hydrogen fuel-cell vehicles could be a costly mistake as a strategy for combating global climate change and for decreasing U.S. dependence on oil, many energy experts say. The problem, these critics argue, is that powering electric vehicles with hydrogen fuel cells is both inefficient and expensive.
Hydrogen fuel must be extracted from fossil fuels or water–both energy-consuming processes. Once produced, the gas must be compressed or liquefied for distribution, and this process and the distribution itself take yet more energy. By the time the hydrogen has been delivered to the fuel cell for conversion to electricity, then, a significant amount of energy has been lost to these processes.
“Along the way, you’ve thrown away nearly three-quarters of the electricity. No one in their right mind would do that–if your alternative is to just string a power line from zero-carbon electricity and charge a battery onboard a car,” says Joseph Romm, executive director of the Center for Energy and Climate Solutions, and formerly in charge of energy efficiency and renewable energy at the U.S. Department of Energy.
Romm says a more promising alternative to internal-combustion engines are plug-in hybrids, which combine an electric motor powered by batteries with a conventional gasoline- or diesel-powered engine, but rely on the electric motor far more than today’s hybrids. Plug-in hybrids, which are being developed by Toyota, with conversion kits for ordinary hybrids already available through several companies, would not eliminate the use of gas, but they would cut down on it significantly. In one type of plug-in hybrid, electricity from the grid can provide enough power for an average commute, at a fraction of the cost of gasoline.