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About hydrogen
Fuel cells run on hydrogen, the simplest element and most plentiful gas in the universe. Each hydrogen molecule has two atoms of hydrogen, which explains the "H2" symbol we often see. Hydrogen is the lightest element, with a density of 0.08988 grams per liter at standard pressure, yet it has the highest energy content per unit weight of all fuels: 52,000 Btu/lb, or 3 times the energy of 1pound of gasoline.
Hydrogen is never found as its own element on earth - it is always combined with other elements such as oxygen and carbon. Hydrogen can be extracted from virtually any hydrogen-containing molecule and is the ultimate clean energy carrier. It is safe to manufacture. And hydrogen's chemical energy can be harnessed pollution-free.
Fuel flexibility means Energy Security: Hydrogen can be produced from a variety of sources:
Traditional: natural gas, gasoline, diesel, propane
Renewable/alternative fuels: methanol, ethanol, landfill gas, bio-gas, methane
Water: using electrolysis, solar or wind power
Innovative: sodium borohydride, algae, magnesium, aluminium and more
Hydrogen supply
Since fuel cells convert hydrogen into electricity, the main question on everybody's mind is "Where and how am I going to get the hydrogen to fuel up my fuel cell product of vehicle?" Many options are being explored to deliver hydrogen to end-users:
Centralized production and delivery. Hydrogen production and delivery services - including a limited pipeline system - already serve the needs of today's industrial demand.
On-Site Production. The energy station of the future might produce hydrogen on demand from natural gas, other compounds or even water.
Innovative Approaches. Fuel cell products that generate electrical power sometimes come with hydrogen generators called reformers. An energy station might purchase one of these units, use the electricity for operations and tap into the reformer to produce hydrogen for vehicles.
Power from the sun. The ultimate solution might be solar powered hydrogen filling stations, where electricity generated by the sun (or by a windmill) is used to extract hydrogen from water. This is not as far out as it sounds. Two such stations already are operating in Southern California.
Hydrogen storage
Because hydrogen is such a light gas, it is difficult to store a large amount in a small space. Researchers are examining an impressive array of storage options, including compressed hydrogen tanks, liquid hydrogen tanks, metal hydride solid state hydrogen storge, and chemical hydrides as dry fuel cartridges. Another option would be to store hydrogen compounds as – methanol, gasoline, or other compounds and extract the hydrogen using reformer technologies.
Safety
Because of its high energy content, hydrogen must be handled properly, just as gasoline and natural gas today require careful handling. Hydrogen is no more dangerous than other fuels, just different.
Hydrogen-based fuels like “town gas” were used in many communities in the U.S. and are still used around the world.
Hydrogen is made, shipped and used safely today in many industries worldwide. Hydrogen producers and users have generated an impeccable safety record over the last half-century.
Liquid hydrogen trucks have carried on the nation's roadways an average 70 million gallons of liquid hydrogen per year without major incident.
Hydrogen has been handled and sent through hundreds of miles of pipelines with relative safety for the oil, chemical, and iron industries.
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