This report responds to a request from the House Committee on Science and Technology and its Subcommittee on Energy Development and Applications to analyze a range of new electric power generating, storage, and load management technologies. The Office of Technology Assessment (OTA) examined these technologies in terms of their current and expected cost and performance, potential contribution to new generating capacity, and interconnection with the electric utility grid. The study analyzes increased use of these technologies as one of a number of strategies by electric utilities to enhance flexibility in accommodating future uncertainties. The study also addresses the circumstances under which these technologies could play a significant role in the U.S. electric power supply in the 1990s. Finally, alternative federal policy initiatives for accelerating the commercialization of these technologies are examined. The study does not address the more traditional technologies of central station coal or nuclear, nor does it analyze advanced nuclear or combined-cycle systems and enhancements to pulverized coal plants such as supercritical boilers, limestone, injection, or advanced scrubber systems. In addition, more renewable technologies such as low-head hydropower or refuse- or wood-fired steam plants are not discussed. The new technologies are discussed under two categories: (1) generating (solar technologies, wind turbines, geothermal power, fuel cells, and combustion technologies); and (2) energy storage (compressed air energy storage and advanced batteries). (JN)