Hydrogen fuel

Hydrogen fuel is a zero-emission fuel which uses electrochemical cells, or combustion in internal engines, to power vehicles and electric devices. It is also used in the propulsion of spacecraft and can potentially be mass-produced and commercialized for passenger vehicles and aircraft.

Chemistry

Hydrogen is the first element on the periodic table, making it the lightest element on earth. It is also the most abundant element on the planet. However, since hydrogen gas is so light, it rises in the atmosphere and is therefore rarely found in its pure form, H₂. In a flame of pure hydrogen gas, burning in air, the hydrogen (H₂) reacts with oxygen (O₂) to form water (H₂O) and releases heat. Other than water, hydrogen combustion may yield small amounts of nitrogen oxides.

Combustion heat enables hydrogen to act as a fuel. Nevertheless, hydrogen is an energy carrier, like electricity, not an energy resource. Energy firms must first produce the hydrogen gas, and that production induces environmental impacts. Hydrogen production always requires more energy than can be retrieved from the gas as a fuel later on. This is a limitation of the physical law of the conservation of energy.

Hydrogen lies in the first group and first period in the periodic table. Hydrogen is neither a metal nor a non metal but still is considered as non metal. It acts as a metalloid when compressed to high densities.

Manufacturing

Main article: Hydrogen production

Because pure hydrogen does not occur naturally, it takes energy to manufacture it. There are different ways to manufacture it, such as, electrolysis and steam-methane reforming process. In electrolysis, electricity is run through water to separate the hydrogen and oxygen atoms. This method can be used by using wind, solar, geothermal, hydro, fossil fuels, biomass, and many other resources. The more natural methods of making electricity (wind, solar, hydro, geothermal, biomass), rather than fossil fuels, would be better used as to continue the environment-friendly process of the fuel. Obtaining hydrogen from this process is being studied as a viable way to produce it domestically at a low cost. Steam-methane reforming process extracts the hydrogen from methane. However, this reaction causes a side production of carbon dioxide and carbon monoxide which are greenhouse gases and contribute to global warming. Even so, the current leading technology for producing hydrogen in large quantities is steam reforming of methane gas (CH₄). Other methods are discussed in the Hydrogen Production article.

Energy

Once manufactured, hydrogen is an energy carrier (i.e. a store for energy first generated by other means). The energy is eventually delivered as heat when the hydrogen is burned. The heat in a hydrogen flame is a radiant emission from the newly formed water molecules. The water molecules are in an excited state on initial formation and then transition to a ground state; the transition unleashing thermal radiation. When burning in air, the temperature is roughly 2000°C.

Uses

Main article: Hydrogen economy

Hydrogen fuel can provide motive power for cars, boats and airplanes, portable fuel cell applications or stationary fuel cell applications, which can power an electric motor.

With regard to safety from unwanted explosions, hydrogen fuel in automotive vehicles is at least as safe as gasoline.”

See also

• HCNG
• Hydrogen safety
• Hydrogen storage
• Hydrogen compressor
• Oxyhydrogen flame
• Hydrogen technologies
• Hydrogen vehicle
• Fuel cell vehicle

External links

• Hydrogen Fuel

Bibliography

• McCarthy, John. "Hydrogen". 

• Energy Information Administration. "Hydrogen explained to a juvenile audience". EIA Official Energy Statistics from the U.S. Government. 

• Milbrandt, A. [afdc.energy.gov/afdc/pdfs/41134.pdf "Hydrogen Production from Key Renewable Resources in the United States"] . U.S. Department of Energy, National Renewable Energy Laboratory. Retrieved March 24, 2011. 
• Hydrogen as the fuel of the future, report by the DLR