Hydrogen Basics

Hydrogen (H2) is a potentially emissions-free alternative fuel that can be produced from domestic resources. Although not widely used today as a transportation fuel, government and industry researchers are working toward the goal of clean, economical, and safe hydrogen production and fuel-cell electric vehicles. For more information, see fuel properties and the Hydrogen Analysis Resource Center.

Hydrogen is locked up in enormous quantities in water (H2O), hydrocarbons (such as methane, CH4), and other organic matter. Efficiently producing hydrogen from these compounds is one of the challenges of using hydrogen as a fuel.

Currently, steam reforming of methane (natural gas) accounts for the majority of the hydrogen produced in the United States. Almost all of the hydrogen produced here each year is used for refining petroleum, treating metals, producing fertilizer, and processing foods. Hydrogen has been used for space flight since the 1950s. Learn more about hydrogen and fuel cells from the National Aeronautics and Space Administration.

Hydrogen also can be used to power fuel cell electric vehicles, which are zero-emission vehicles. Major research and development efforts are aimed at making fuel cell electric vehicles practical for widespread use.

Learn more about hydrogen and fuel cells from the Fuel Cell Technologies Office.

Hydrogen as an Alternative Fuel

Hydrogen is considered an alternative fuel under the Energy Policy Act of 1992. The interest in hydrogen as an alternative transportation fuel stems from its ability to power fuel cells in zero-emission electric vehicles, its potential for domestic production, and the fuel cell vehicle's potential for high efficiency—it's two to three times more efficient than an internal combustion engine. Learn more about fuel cells.

The energy in 2.2 pounds (1 kilogram) of hydrogen gas is about the same as the energy in 1 gallon of gasoline. Because hydrogen has a low volumetric energy density, it is important for a fuel cell vehicle to store enough fuel onboard to have a driving range comparable to conventional vehicles. Some hydrogen storage technologies are available and undergoing more research and demonstration. These technologies include compressing gaseous hydrogen in high-pressure tanks at up to 10,000 pounds per square inch. Other storage technologies are under development, including bonding hydrogen chemically with a material such as metal hydride, or low temperature sorbent materials. Learn more about hydrogen storage.

Chart with different-size bars showing the relative volume needed for various hydrogen storage methods to achieve a greater than 300 mile driving range. At top is the shortest bar, representing 20 gallons of gasoline. Below this bar is a bar of equal length representing the year 2015 target for hydrogen storage. Below the 2015 target bar are five more bars, starting with a bar representing the volume of liquid hydrogen required, which is more than twice as long as the 2015 target bar. The rest of the bars increase in length--with each bar longer than the one above it--in the following order, representing the increasing volumes required to enable a 300-mile range: chemical hydrides, compressed 10,000 psi, metal hydrides, and compressed 5,000 psi.

Source: Hydrogen.energy.gov

Most of the few currently operating hydrogen fueling stations are in California. Find hydrogen fueling stations near you.