Source: National Aeronautics and Space Administration (NASA) (public domain)
Source: Adapted from the National Energy Education Project (public domain)
Source: Wikimedia Commons
Use of hydrogen
Nearly all of the hydrogen consumed in the United States is used by industry for refining petroleum, treating metals, producing fertilizer, and processing foods.
Rocket fuel is the main use of hydrogen for energy
The National Aeronautics and Space Administration (NASA) is the largest user of hydrogen as a fuel. NASA began using liquid hydrogen in the 1950s as a rocket fuel, and NASA was one of the first to use fuel cells to power the electrical systems on space craft.
Hydrogen fuel cells produce electricity
Hydrogen fuel cells produce electricity by combining hydrogen and oxygen atoms. This combination results in an electrical current. A fuel cell is two to three times more efficient than an internal combustion engine running on gasoline.
Many different types of fuel cells are available for a wide range of applications. Small fuel cells can power laptop computers, cell phones, and military applications. Large fuel cells can provide electricity for emergency power in buildings and in remote areas that do not have power lines. Hydrogen use in vehicles is a major focus of fuel cell research and development.
Hydrogen use in vehicles
The interest in hydrogen as an alternative transportation fuel is based on hydrogen's 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.
In the United States, about 500 hydrogen-fueled vehicles are in use, and about 330 of those are registered in California. Most hydrogen-fueled vehicles are automobiles and transit buses that have an electric motor powered by a fuel cell. A few of these vehicles burn hydrogen directly. The high cost of fuel cells and the limited availability of hydrogen fueling stations have limited the number of hydrogen-fueled vehicles.
The refueling challenge
Production of hydrogen cars is limited because people won't buy hydrogen cars if refueling stations are not easily accessible, and companies won't build refueling stations if they don't have customers with hydrogen-fueled vehicles. In the United States, about 55 hydrogen refueling stations for vehicles are operating. About 30 of these stations are available for public use, nearly all of which are located in California. The California Energy Commission has a program to help fund the development of publicly accessible hydrogen refueling stations throughout California to promote a consumer market for zero-emission fuel cell vehicles.