Renewable Energy - Hydrogen: A Fuel Of The Future?

Hydrogen, the lightest and most abundant chemical element, is the ideal fuel from the environmental point of view. Its combustion produces only water vapor, and it is entirely carbon-free. Three-quarters of the mass of the universe is hydrogen, so in theory the supply is ample. However, the combustible form of hydrogen is a gas and is not found in nature. The many compounds containing hydrogen—water, for example—cannot be converted into pure hydrogen without the expenditure of energy. The amount of energy that would be required to make gas is about the same as the amount of energy that would be obtained by the combustion of the hydrogen. Therefore, with today's technology, little or nothing could be gained from an energy point of view.

Scientists, however, are researching ways to produce hydrogen gas economically. Whether this will come from fusion, solar energy, or elsewhere is not possible to predict now. Scientists have considered the possibility of a transition to hydrogen for more than a century, and today many see hydrogen as the logical "third-wave" fuel, with hydrogen gas following oil, just as oil replaced coal decades earlier. For now, however, widespread use of hydrogen as fuel is purely theoretical.

Research into the use of hydrogen as a fuel got a boost when President George W. Bush announced a hydrogen fuel initiative in his 2003 State of the Union address. By the end of 2004, the Department of Energy had awarded $75 million in research grants in support of this initiative.