Hydrogen Fuel Cells

Fuel cells are emerging as a viable source of heat and power. They run on pure hydrogen.

Hydrogen is the most basic element in the universe. An atom of hydrogen consists of only one proton and one electron. It's also the most abundant element in the universe. However, hydrogen doesn't occur naturally as a gas on the Earth - it's always combined with other elements. Water, for example, is a combination of hydrogen and oxygen (H2O), and hydrocarbons, such as methane (CH4) are combinations of hydrogen and carbon. Methane is of course, the natural gas that most of us have piped into our homes.

Hydrogen can be separated from hydrocarbons through the application of heat - a process known as reforming. Currently, most hydrogen is made this way from natural gas. An electrical current can also be used to separate water into its components of oxygen and hydrogen. This process is known as electrolysis. Some algae and bacteria, using sunlight as their energy source, even give off hydrogen under certain conditions.

Hydrogen is high in energy, yet an engine that burns pure hydrogen produces almost no pollution. NASA has used liquid hydrogen since the 1970s to propel the space shuttle and other rockets into orbit. Hydrogen fuel cells power the shuttle's electrical systems, producing a clean byproduct - pure water, which the crew drinks.

A fuel cell takes hydrogen and oxygen and produces electricity, heat, and water. Fuel cells are very similar to batteries. Both convert the energy produced by a chemical reaction into usable electric power. However, a fuel cell will produce electricity for as long as hydrogen is supplied, never losing its charge.

Fuel cells are a promising technology for use as a source of heat and electricity for buildings, and as an electrical power source for electric motors propelling vehicles. Fuel cells operate best on pure hydrogen. But fuels like natural gas, methanol, or even gasoline can be reformed to produce the hydrogen required for fuel them.

The other promising attribute is that Hydrogen can also be transported (like electricity) to locations where it is needed.

The image on the right is of a car powered by a fuel cell being refuelled with hydrogen

Watch this space as we keep you up to date with developments on the fuel cell front.

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