FUEL CELL? What’s that?

A fuel cell is a device that converts chemical energy from a fuel into electricity. This occurs through the chemical reaction of positively charged hydrogen ions (from the fuel) with oxygen or another oxidizing agent. In a classic battery, the chemicals required are already present in the battery in fixed and limited quantities. Fuel cells are different: given a flow of fuel and oxygen or air to sustain the chemical reaction, they have the advantage of being able to produce electricity continuously for as long as these inputs are supplied. This opens the door to many applications where classic batteries are impractical or uncompetitive. The most common fuel used in fuel cells is hydrogen, which can be generated from pure water using electricity from renewable sources. When the fuel cell is operated, the only end products are water and heat!

HYDROGEN? How can one obtain that?

On Earth, hydrogen is generally found in compounds with other elements. The most common are carbon, with which it forms methane (CH4), and oxygen, with which it forms water (H2O). To get pure hydrogen for industrial applications, it must be separated from the chemical elements to which it is bound. Today, 95% of hydrogen is extracted either from wood or from fossil fuels, such as natural gas and oil.

Hydrogen can also be produced using electricity, through electrolysis of water. An electric current is used to split water (H2O) into oxygen (O2) and hydrogen (H2). The great advantage of this method is that the energy can come from renewable sources! This is currently the most sustainable method of producing hydrogen.

In fact, hydrogen production represents an ideal way to convert electricity into a chemical fuel when production from renewable sources exceeds demand over a long period of time. For example, excess solar energy produced during summer would be fully utilised, and would be dispatchable – available whenever needed.


Hydrogen is the most appropriate technology for large-scale, long-term storage. It is highly scalable, and does not suffer from losses such as the self-discharge typical with batteries.

Hydrogen can be stored for subsequent use in many ways, including high–pressure tanks, cryogenics, and chemical compounds that reversibly release H2 upon heating.  Underground hydrogen storage is used to provide grid-scale storage of hydrogen produced from intermittent energy sources, such as wind or solar power. Underground storage is also adapted to providing fuel for transportation, particularly for hybrid-electric vehicles, ships and airplanes. Stationary fuel cells are used for commercial, industrial and residential primary and backup power generation. Fuel cells are very useful as power sources in remote/off-grid applications, such as spacecraft, remote weather stations, large parks, data centres and rural locations. A fuel cell system running on hydrogen and oxygen can be compact and lightweight, and have no major moving parts. Because hydrogen-oxygen fuel cells have no major moving parts and do not involve combustion, in ideal conditions they can achieve up to 99.9999% reliability.