Hydrogen has the simplest structure of any element and is the most common gas in the universe. The sun uses hydrogen to power itself and heat the earth, and car manufacturers are beginning to use it as a fuel to replace gasoline. In addition to producing less pollution, hydrogen has more power than gas when measured by weight.
According to the US Energy Information Administration, hydrogen has three times the power of gasoline by weight and has the highest energy content of any known fuel.
Liquid hydrogen has an extremely low density (0.07 grams per cubic centimeter). Hydrogen needs about four times the volume of gas in order to produce the same amount of energy.
Hydrogen fuel tank designers must find a way to safely compress hydrogen in order better compete with gasoline. A regular 15 gallon gas tank holds 90 pounds of gasoline. The same size tank would only hold about eight pounds of hydrogen.
Hydrogen can be generated from renewable resources, including air and water, or it can be refined from non-renewable resources, such as fossil fuels. Should hydrogen be produced from fossil fuels, the resulting carbon emissions could offset the environment gains realized from clean-running hydrogen engines.
As of 2010, manufacturers cannot produce enough hydrogen, or hydrogen cars, to make it a more cost effective option over gasoline.
