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Fuel Cell that Traveled to Outer Space

What was the power source of the Apollo 11 rocket that carried the first men to the moon? What is the power source of the space shuttle? The answer is a fuel cell. But, what is a fuel cell?

Water breaks down into hydrogen and oxygen when electricity is passed through the water. In contrast, by combining hydrogen and oxygen in a chemical reaction, water is produced and electricity is generated. Fuel cells are like "electricity generators" which make electricity from hydrogen and oxygen.

Now many companies including automobile manufacturers are competing to develop fuel cells for actual use. Why are they so eager? It's because fuel cells have many advantages:

1) Generate electricity efficiently
Some energy is lost when a turbine is used to generate electricity, but a fuel cell doesn't lose any energy at all because it generates electricity directly by a chemical reaction.

2) Heat can be utilized
The heat that is produced through generating electricity can be utilized for supplying hot water and heating. More than 80% of the raw energy for fuel cells can be used as electricity or heat. Compared to the 35% efficiency for thermal power generation, there is little waste.

3) Environmentally Friendly
Water is the only waste product from power generation with fuel cells. Also, no carbon dioxide is emitted because nothing is burned.

4) Quiet
Since a fuel cell has no engine or turbine, it makes little noise and can be installed even at home to generate power.

5) Various Sizes
A fuel cell for household use generates power as efficiently as that for a large power plant. A household fuel cell generator is just about the same size as the outside part of air conditioners commonly used in Japan (about 80 x 35 x 80 centimeters). It is small, isn't it?

The raw materials for a fuel cell are hydrogen and oxygen. We have no problem with oxygen since the air has oxygen in it. Research and development for the production of hydrogen are in progress. As mentioned before, "water is the only waste product" but carbon dioxide might be emitted depending on how the hydrogen is produced.

For example, hydrogen can be produced by burning petroleum. Carbon dioxide is emitted when the hydrogen is produced by this method. So, even if we say hydrogen is the raw material to generate the electricity in fuel cells, we need to be aware of how the hydrogen is made.

Hydrogen can be produced from natural gas too. Soon we will be able to generate power at home by installing a fuel cell on the veranda or in the yard and connecting to it with a gas pipe.

If we can generate power at a low cost using solar or wind energy, we can use that electricity to make hydrogen from water inexpensively with the clean power. Like natural gas, hydrogen can be stored or supplied through a pipe. Once an unstable energy source such as solar or wind energy is turned into hydrogen, we can generate electricity anytime and anywhere with a fuel cell.

See all the vapor coming out of the fuel cell at the bottom of the
railcar?

The World's First Fuel-Cell Hybrid Railcar
(under development by the East Japan Railway Company)
Photo courtesy of the East Japan Railway Company

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