Hydrogen is not an Energy Source

Many people believe that hydrogen is an alternative to fossil fuels for powering our society. They believe that because hydrogen powered engines produce little or no CO2 and are not based on fossil fuels we can solve two problems with one technology: the problem of CO2 emissions and the problem of our dependence on foreign oil.

This is not the case. It’s true that the element hydrogen, when combined with oxygen, produces a large amount of energy – it’s what puts the space shuttle into orbit. The problem is that just about all the hydrogen atoms on earth are bound up with other atoms in the form of molecules. To use hydrogen as a fuel it must first be liberated from molecules and this liberation takes energy. In fact, because of unavoidable inefficiencies, it takes more energy to produce useable free hydrogen than is recovered later when the free hydrogen is combined with oxygen.

What does this mean? It means that on earth, hydrogen is not a source of energy like fossil fuels are. Instead, hydrogen is a means of storing and transporting energy. A tank full of hydrogen used to fuel a hydrogen-powered vehicle is more akin to a battery in an electric vehicle. Instead of a power plant filling up a battery with electrical energy, the power plant is used to produce free hydrogen, which is then collected and used to fill a fuel tank. The power needed to produce free hydrogen comes from the same place the rest of our power comes from, in the U.S. (year 2000 estimates): 69% fossil fuels, 15% hydroelectric, 14% nuclear, ~1% all others (including wind and solar).

There is one caveat of course; this all pertains to obtaining energy from hydrogen when used in a chemical reaction. Hydrogen is a potential source of energy as a fuel in a nuclear fusion reactor – hydrogen fusion is what powers the sun. But, unless there is some breakthrough from out in left field, nuclear fusion reactors are still a long way off and so is hydrogen as an energy source.