Fuel Cells for Electric Utility Power Generation

Abstract

Publisher Summary A fuel cell is an electrochemical device that continuously converts the chemical energy of a fuel to electrical energy. The essential difference between a fuel cell and a storage battery is the continuous nature of the fuel and oxidant supply. A fuel cell consists of two catalyzed carbon rods, immersed in an electrolyte and separated by a gas barrier. The fuel is bubbled across the surface of one electrode while the oxidant is bubbled across the other electrode. When the rods are electrically connected through an external load, the hydrogen dissociates on the catalytic surface of the fuel electrode, forming hydrogen ions and electrons. The hydrogen ions migrate through the electrolyte and separator to the catalytic surface of the oxygen electrode. Simultaneously, the electrons move through the external circuit to the oxygen electrode. The oxygen, hydrogen ions, and electrons combine at the oxygen electrode to form water. A fuel cell power, depending on its size, type, and sophistication, may require controls of varying complexity, an oxidant subsystem, and thermal and fluid management subsystems. This chapter focuses on fuel cells for electric utility power generation, which represents the most likely large-scale use of fuel cells.