A fuel cell is an electrochemical device that converts chemical energy from a fuel into electric energy using an electrochemical rather than a combustion process. Electric power is generated from the reaction between a fuel supply (natural gas or another source) and an oxidizing agent (typically air).
Fuel cells require hydrogen as the fuel source. However, due to the absence of a well-established hydrogen infrastructure, most fuel cells are designed to produce hydrogen internally from a readily available fuel source such as natural gas or a renewable biogas. Similarly, fuel cells are designed to produce oxygen internally by extracting it from air. Both the hydrogen and oxygen are used in the electrochemical reaction to produce electricity, with heat and water as byproducts.
A fuel cell is similar to a battery in some respects in that electrical energy is created by an electrochemical process. However, unlike a battery, which only has a discrete quantity of chemical reactants stored inside the device to create electrical energy, a fuel cell operates via a continuous feed of inputs (the hydrogen and oxygen). As long as there are inputs, the fuel cell will continue to convert the energy in the fuel to electricity. Thus the benefit of a fuel cell is that is does not requiring recharging like a battery.
Fuel cells produce direct current (DC) electricity and since the conversion of the fuel to energy takes place via an electrochemical process, not combustion, the process is highly efficient, clean, and reduces pollutants (such as NOx, SOx, and PM10) to a negligible amount.
Fuel Cell Fun Facts
1. Sir William Grove constructed the first fuel cell in 1839.
2. In the early 1960’s, NASA began incorporating fuel cells into manned space vehicles.
3. There is no combustion in fuel cells, only electrochemical reactions.
4. Some fuel cells produce heat that can be recovered and used for a variety of applications (e.g., like heating water or swimming pools).