The Drawbacks of Hydrogen Fuel Cell Cars
The concept of using hydrogen fuel cells to power the next generation of vehicles is often posed as the solution to the many problems created by automobile pollution and oil dependency. Don’t believe the hype.
Fuel cell cars are a long way off: Hybrid cars already exist as commercial products and are available to cut pollution now. On the other hand, fuel-cell cars are expected on the same schedule as NASA’s manned trip to Mars—and have about the same level of likelihood.
Hydrogen fuel cells cost more: Hydrogen fuel cells in vehicles are about twice as efficient as internal-combustion engines; however, hydrogen fuel cell costs are nearly 100 times as much per unit of power produced. Hydrogen is a fuel carrier, and should not be viewed as a source of energy.
Fuel-cell vehicles are dirtier: Fuel-cell cars emit only water vapor and heat, but the creation of the hydrogen fuel (via burning coal, for example) can be responsible for more overall greenhouse gas emissions than conventional internal combustion engines.
Hydrogen fuel is harder to transport: Moving large volumes of hydrogen gas requires compressing it. Hydrogen compression rates mean that 15 trucks are required to power the same number of cars that could be served by a single gasoline tanker. Liquid hydrogen would require less (about three trucks), but would require substantially more effort and energy to liquefy.
Hydrogen is much more dangerous: As dangerous as a leak of natural gas is, a hydrogen leak is worse because hydrogen ignites at a wider range of concentrations and requires less energy to ignite. And hydrogen burns invisibly. "It’s scary—you cannot see the flame, " says Michael D. Amiridis, chair of the Chemical Engineering Department at the University of South Carolina.
Cars may be the last place that fuel cells are used on a commercial scale. Chances are much better that they will start in stationary applications, or in cell phones and laptop computers. Other perhaps more promising substitutes for oil-based transportation include natural gas, bio-fuels, and electricity stored in new generation batteries in electric or hybrid cars.
Hybrids as Bridge to Fuel Cells
The many obstacles to hydrogen fuel cell vehicles will not stop the auto companies and the government from investing big money into research and development. If the researchers stand any chance of success, they will need to better understand today’s hybrid gas-electric cars. That’s why hybrids are considered a bridge technology. "An awful lot of today’s Prius is similar to the fuel cell vehicles we’re building and testing, " said Bill Bergen, Toyota’s national dealer education manager for operations and technical training.