What is a Fuel Cell?
Fuel cells convert fuel and air directly into power and heat through a quiet, efficient, solid-state electro-chemical reaction.
Fuel cells generate power significantly more efficiently than internal combustion engines (ICEs) because they convert chemical energy directly to electrical current rather than via an efficiency sapping mechanical intermediate phase. Fuel cells operate at maximum efficiency at part load (where most ICE generators operate very inefficiently) and their efficiency is largely unaffected by size. In addition, the modular design allows the fuel cells to be stacked to match the specific output power needed.
The simple nature of their design and operation makes fuel cells highly reliable. If pure hydrogen is used as a fuel then the only outputs are electricity, heat and water vapour. The Ceres Power fuel cell can also operate on a range of hydrocarbon fuels such as natural gas and LPG as well as renewable biofuels.
How does a fuel cell work?
Fuel passes over the anode side and air passes over the cathode. Sandwiched between the anode and cathode is the very thin, gas tight, electrically insulating but ion conducting electrolyte layer. An external circuit connects the anode to the cathode and provides the mechanism to power electrical devices.
The combination of the materials used to make the fuel cell components, the type of fuel used and the operating temperature allow electricity to be generated via a chemical reaction rather than burning the fuel. Negatively charged oxygen ions flow from the cathode and across the electrolyte. At the anode the oxygen ions combine with positively charged hydrogen ions and release electrons that then flow around the external circuit to the cathode generating direct current. Current will continue to be produced as long as there is a supply of fuel and air to the fuel cell.
Heat is also liberated by fuel/air reaction and can be captured and coupled into a heat exchanger to meet local heating requirements.