NASA uses hydrogen to launch the space shuttle. Image Courtesy of: NASA

Hydrogen is the choice of fuel for launching rockets into space because it’s low weight and high energy content. Spacecraft have the luxury of dropping fuel canisters as they go, which allows them to carry enough fuel to escape Earth’s gravity and then drop the extra weight when the fuel is used.

So how can we use hydrogen to power vehicles; can you imagine what would happen if car’s lost their fuel tanks once they were empty? Fortunately that does not need to happen. Hydrogen storage is technical challenge that needs a better solution. Current technology allows most fuel cell vehicles to travel about 180 miles.

Because hydrogen is has three times the energy content of the equivalent volume of gasoline, a hydrogen powered vehicle gets better gas mileage. The simplicity of hydrogen (two hydrogen atoms held together in a single H-H bond) makes for very fast rates of energy release, or rapid kinetics. Compare this to octane, a primary constituent of gasoline, which has 25 chemical bonds per molecule (7 carbon-carbon and 18 carbon-hydrogen bonds). This not only bodes well for hydrogen's use in conventional combustion, but it also opens the possibility of high-efficiency electrochemical energy transducers, such as fuel cells. The electrochemical option is estimated to offer more than twice the fuel economy of an internal combustion engine-based power train, while producing no polluting emissions.⁽¹⁾