HYDRODEN FUEL CELLS

Subject : Science and tech

How does hydrogen fuel cell work?

• A fuel cell is an electrochemical cell that converts the chemical energy of a fuel (often hydrogen in the case of Hydrogen Fuel Cell) and an oxidizing agent (often oxygen) into electricity through a pair of redox reactions.
• A Fuel Cell consists of an anode, a cathode, and an electrolyte that allows ions, often positively charged hydrogen ions (protons), to move between the two sides of the fuel cell.
• A fuel cell converts chemical potential energy (energy stored in molecular bonds) into electrical energy.
• A PEM (Proton Exchange Membrane) cell uses hydrogen gas (H2) and oxygen gas (O2) as fuel.
• The products of the reaction in the cell are water, electricity, and heat.
• This is a big improvement over internal combustion engines, coal burning power plants, and nuclear power plants, all of which produce harmful by-products.
• Since O2 is readily available in the atmosphere, we only need to supply the fuel cell with H2 which can come from an electrolysis process (see Alkaline electrolysis or PEM electrolysis).

Source: Wikipedia.org

Advantages of the Hydrogen Fuel Cell technology:

• By converting chemical potential energy directly into electrical energy, fuel cells avoid the “thermal bottleneck” (a consequence of the 2nd law of thermodynamics) and are thus inherently more efficient than combustion engines, which must first convert chemical potential energy into heat, and then mechanical work.
• Direct emissions from a fuel cell vehicle are just water and a little heat. This is a huge improvement over the internal combustion engine’s litany of greenhouse gases.
• Fuel cells have no moving parts. They are thus much more reliable than traditional engines.
• Hydrogen can be produced in an environmentally friendly manner, while oil extraction and refining is very damaging.