Fuel Cell Systems The design of fuel cell systems is complex, and can vary significantly depending upon fuel cell type and application. However, several basic components are found in many fuel cell systems: Fuel cell stack Fuel processor Power conditioners Air compressors Humidifiers FUEL CELL STACK The fuel cell stack is the heart of a fuel cell power system. It generates electricity in the form of direct current (DC) from electro-chemical reactions that take place in the fuel cell. A single fuel cell produces less than 1 V, which is insufficient for most applications. Therefore, individual fuel cells are typically combined in series into a fuel cell stack. A typical fuel cell stack may consist of hundreds of fuel cells. The amount of power produced by a fuel cell depends upon several factors, such as fuel cell type, cell size, the temperature at which it operates, and the pressure of the gases supplied to the cell. Learn more about the parts of a fuel cell. FUEL PROCESSOR The fuel pr...