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Hydrogen Fuelled Cars
Q: How does
a Hydrogen engine work?
Electricity generated from solar power is used to split water into hydrogen and oxygen. Oxygen is released into the atmosphere, while hydrogen is liquefied and stored at a very low temperature (-253 °C).
During internal combustion, the hydrogen combines with oxygen. The resulting energy powers the vehicle, while the hydrogen is returned to the environment as water. Harmful emissions are virtually eliminated.
By cooling hydrogen to -253°C, hydrogen is shrunk to a thousandth of its original volume. Seventy layers of
aluminum and fiberglass sheets between the exterior and interior vehicle walls ensure that the liquid hydrogen remains at extremely low temperatures.
Q: How does a fuel cell work?
A fuel cell introduces hydrogen atoms to oxygen atoms and induces them to connect. The chemical reaction of hydrogen and oxygen is used to create electricity. The by-products of this are heat and water.
Q: Isn't hydrogen explosive?
Yes, as is gasoline. The key to safety is to store hydrogen in a hardy container that will survive collisions, and to keep sparks and static electricity away from it.
Q: Where does hydrogen come from?
It's the most common element in the universe, but big oil companies, who get it from petroleum, make most commercially available hydrogen.
Q: Is the current method for getting hydrogen good for the environment?
No. The preferred long-term solution is probably using electricity to break water down into hydrogen and oxygen. However, it is easier to control the emissions from a big industrial refinery than from millions of cars.
Q: Is gasoline less expensive than hydrogen?
Yes, at present. Automakers expect the cost of hydrogen to fall before fuel cells go into widespread use.
Q: How long does it take to refuel a hydrogen
fuelled car?
Scientists and engineers are still puzzling out the best way to store hydrogen in a car so it is too early to know how long it takes to refuel. However, the car companies say the technology won't be ready for prime time until refueling time is the same or less than with gasoline.
Q: Will we refuel the cars in a way similar to that used to refuel our cars today?
Yes, we will most likely refuel at filling stations set up to handle hydrogen.
Q: At what frequency do I have to plug
in a fuel cell car?
Never. It produces its own electricity on board.
Q: What are the technologies under consideration for where fuel cell cars will store their hydrogen?
Two main competing technologies are:
- Keep it compressed in tanks. This will require new materials that are very tough and much less expensive than anything available today.
- Keep it in solid-state storage, which could be less expensive than compressed tanks and could hold more hydrogen. The hydrogen is chemically attached to another material. DaimlerChrysler does this by combining hydrogen with Borax. Other researchers are experimenting with combining the hydrogen with metals. The big hurdle is storing enough hydrogen this way to give the car a 300-mile cruising range.
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