America's Space Shuttle: Electrical Power System NASA Astronaut Training Manual (EPS 2102‪)‬

This unique and historic document provides extraordinary detail about the Space Shuttle's electrical power system. The official NASA astronaut training manuals comprised a major part of the formal flight crew training process, and were used by flight controllers as well. These internal NASA manuals were produced by the Mission Operations Directorate (Space Flight Training Division branch) at NASA's Johnson Space Center. The manuals and workbooks are extremely detailed and comprehensive, and are designed for self-study. A full listing of all acronyms and abbreviations used in the text is included. They provide a superb way to learn about Shuttle systems, hardware, and operational procedures. Special emphasis on crew interaction with the displays, controls, and hardware is included.

This manual covers the electrical power system (or EPS). The electrical power system (EPS) consists of the equipment and the reactants which produce and distribute electrical power throughout the orbiter, fulfilling all the orbiter external tank (ET), solid rocket booster (SRB), and payload power requirements when not connected to ground support equipment (GSE). The operation of the EPS can be divided into three critical functions: (1) energy storage, (2) power production, and (3) power distribution. The power reactant storage and distribution (PRSD) subsystem provides energy storage. It stores energy in chemical form as cryogenic hydrogen (H2) and oxygen (O2) and supplies these reactants for use in power production. The PRSD subsystem also supplies O2 to the environmental control and life support system (ECLSS) for crew respiration. The fuel cell (FC) subsystem provides power production. This subsystem consists of three fuel cells which consume the O2 and the H2 provided by the PRSD subsystem and, through a chemical reaction, produce direct current (dc) electricity. The FC subsystem also supplies potable water (H2O) to the ECLSS. The electrical power distribution and control (EPDC) subsystem provides power distribution. This subsystem distributes the dc power generated by the fuel cells to all the dc loads and generates and distributes alternating current (ac) power to all the ac loads.