Wednesday, 11 July 2007

hydrogen fuel cells

Because an external energy source is needed to produce it, hydrogen strictly speaking isn't a primary energy source like coal, sunlight or wind, but instead is generally referred to as being an energy carrier like electricity. Hydrogen's critics claim that since its production invariably involves natural gas, hydrogen's energy budget doesn't add up. And with CO2 being produced every step of the way, hydrogen, it's claimed, isn't very green at all.

Ulf Hafseld, HyNor's project manager, accepts that making hydrogen using fossil fuels isn't sustainable. "The answer is to produce hydrogen from water using electricity from renewable energy, which is very easy," he says. "This is already happening in Berlin, where a small electrolysing plant at a filling station is generating the gas from water, using 100 per cent renewable energy from a hydroelectric plant in the Alps. It produces no CO2 emissions at all."

Along with using renewable energy to produce "green hydrogen", Hafseld believes that the increasing use of hydrogen-powered fuel cells in cars are crucial for maximising hydrogen's potential. "Fuel cells are about twice as efficient as internal combustio
n engines so can help compensate for any energy loss in the gas's production."

* Fuel cells produce electricity from a chemical reaction involving hydrogen and oxygen. They emit no carbon, although it may be released when producing the hydrogen itself.

* Fuel cells will be at the heart of any future hydrogen economy. Their supporters claim that they potentially offer a carbon-free alternative to fossil fuels.

* While fuel-cell cars are expected to reach mass production by 2025, some believe that we will see widespread use of fuel cells in everyday applications within a few years.

* Anticipated uses of fuel cells include mobile phones, laptops, home heating and power plants.
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