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EXPLORATIONS - Fuel Cell Cars

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VOICE ONE:

This is Mary Tillotson.

VOICE TWO:

And this is Steve Ember with the VOA Special English program EXPLORATIONS. Today we tell about a new American program to develop cars that do not cause pollution.

((THEME))

VOICE ONE:

American Energy Secretary Spencer Abraham recently announced a new program to develop cars that effectively use fuel and do not cause pollution. The new energy department program will support research to make a car powered by a fuel cell engine. Mister Abraham calls the proposed vehicle the "Freedom Car."

The energy secretary made his announcement at the Detroit Auto Show in early January. He said the new "Freedom Car" project is meant to bring about a change in government policy. Mister Abraham said "Freedom C-A-R" stands for "Cooperative Automotive Research."

He said using hydrogen instead of gasoline as fuel for cars represents an important step toward reducing America's use of foreign oil. Mister Abraham also said that the fuel cell project will combine government and industrial investments to develop new technologies.

VOICE TWO:

A fuel cell is not a new invention. It is a device which uses hydrogen fuel and oxygen from the air to produce electricity and water. Sir William Grove of Britain invented the first fuel cell in Eighteen-Thirty-Nine. Many different designs have been invented since then.

Graphic Image
Graphic Image

The Gemini and Apollo space ships used fuel cells to create electricity in space. Fuel cells provide all the electrical power on the American space agency's Space Shuttle. The hydrogen used by the fuel cells combines with oxygen to provide all of the drinking water for the astronauts.

This is the way a fuel cell uses hydrogen to create electricity. Hydrogen gas is passed over a metal that reacts electrically. The electrons from the hydrogen separate to form electricity. The remaining part of the hydrogen atom, the proton, combines with oxygen to form water. This process makes electricity without producing the pollution that is created when coal, oil and gasoline are burned as fuels.

VOICE ONE:

Researchers say fuel cells lose less of the energy they produce than other methods of making electricity. They also say that a large number of substances can be used to provide fuel for a fuel cell. Specially treated natural gas, oil and coal all contain the hydrogen necessary to run a fuel cell.

Several companies in the United States, Germany and Canada are developing experimental fuel cells. Yet, most of these devices are part of a large power station. In these power systems, a central fuel cell makes electricity from hydrogen gas. Other machines separate hydrogen from natural gas, oil or coal. These fuel cell systems can be very complex.

((MUSIC BRIDGE))

VOICE TWO:

Hydrogen presents several major problems for those who want to use it to make energy or to power cars. Hydrogen easily combines with other elements, or itself, to create molecules. Yet, it takes a lot of energy to release a hydrogen atom from a molecule. For example, electrolysis is the process of separating a hydrogen atom from an oxygen atom in a molecule of water. In this process, electrical current separates the two atoms, but adds greatly to the cost of making hydrogen gas.

The Department of Energy lists several ways that hydrogen can be released from some materials. However, research shows that hydrogen is difficult to separate from complex molecules. The agency estimates that producing electricity from hydrogen would be about ten times more costly than burning natural gas.

VOICE ONE:

Fuel cells also present major problems for engineers who design cars. A single fuel cell has to be large, yet can create only a small amount of electrical power. So, fuel cells need to be combined in a series to produce a strong electrical current. Researchers have been trying to reduce the size of fuel cells for many years.

Some scientists have used new materials to solve the problem. One fuel cell developed by Bell Laboratories is very small. It uses specially processed materials to make a very thin fuel cell. However, these thin fuel cells produce only a small amount of electricity. Experts believe that smaller fuel cells will some day provide power for devices like cellular telephones and computers.

VOICE TWO:

Fuel storage is another major problem in designing a car that is powered by a fuel cell. Fuel cell engines require a large amount of hydrogen to create enough electricity to much too much space. Hydrogen in liquid form can exist only at extremely low temperatures. A fuel tank in a car to hold liquid hydrogen would need to be very large to keep the temperature inside it low.

The cost of a car with a fuel cell engine could also be a major problem. Peter Hoffman is head of The Hydrogen and Fuel Cell Letter. Mister Hoffman supports developing cell energy technology. His estimates suggest that fuel cell cars would cost at least seventy-five thousand dollars.

VOICE ONE:

Experimental fuel cell cars do exist. The car manufacturer Daimler-Chrysler has developed a fuel cell engine small enough to use in a car. The experimental car is called the Chrysler Natrium. Its fuel cell engine runs on a chemical mixture called sodium borohydride. The fuel cell uses hydrogen in the fuel to make electricity.

However, a hydrogen fuel cell powered by the kind of chemical mixture presents new problems. The new fuel is not commonly used today. And, the car would produce huge amounts of borax as waste defeating the purpose of using a fuel cell engine that does not pollute.

((MUSIC BRIDGE))

VOICE TWO:

The new "Freedom Car" program is not the first time the American government has supported research to produce cars that use fuel more effectively. In Nineteen-Ninety-Three, the Clinton administration began a program to design cars that use less fuel. The goal was to develop a car that uses about three times less gasoline than current cars.

The government spent about one-thousand-five-hundred million dollars to aid the research. Much of the research money went to laboratories, universities and government agencies. The New York Times reports that the three biggest car makers -- Ford, General Motors and Chrysler -- received only a small amount of the government support.

VOICE ONE:

That program failed to produce any cars using less fuel that could be sold. It did develop several new materials that are being used in cars today. Yet, American vehicles on average do not use fuel more effectively than they did at the beginning of the program.

Energy Secretary Abraham's announcement in Detroit, Michigan, of the Freedom Car program officially ended that effort. In the proposed federal budget for Two-Thousand-Three, the Bush administration calls for spending one-hundred-fifty million dollars this year on fuel cell research.

VOICE TWO:

Two car companies have successfully developed cars that use regular gasoline far more effectively. The Japanese car company Toyota makes what is called a hybrid car. The model called the Prius uses both electricity and gas to run its engine. Toyota has sold more than twenty-thousand of these cars in the United States. In fact, every Prius ever made has been sold. There is a list of people who want to buy the popular car.

The Japanese car-maker, Honda, also makes a hybrid car that uses gasoline so effectively that it almost meets the goal set by the Clinton administration. The Honda Insight also uses a combination of a gasoline engine and electricity created from the motion of the car itself. Both the Prius and the Insight produce much less waste as well. Toyota says the Prius produces seventy-five percent less pollution than regular cars.

Cars powered by fuel cells would create less pollution than even hybrid cars like the Toyota Prius. However, fuel cell cars will not appear in the market place for many years, until researchers develop new technologies to deal with old problems.

((THEME))

VOICE ONE:

This Special English program was written by Mario Ritter. It was directed by George Grow. Our studio engineer was Wagner Roberts. This is Mary Tillotson.

VOICE TWO:

And this is Steve Ember. Join us again next week for another EXPLORATIONS program on the Voice of America.

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