Conceptual Design of an Htgr System for a Total Energy Application

A conceptual design for a small HTGR in the 100 MWe size range is described. The reactor drives indirect closed-cycle gas turbine power conversion units using helium as the working fluid and provides both electricity and thermal energy (via a 3800 F hot-water utility system) to serve the projected needs of large U.S. Army installations and industrial facilities in the continental U.S. in the post 1985 time frame. The overall system design combines many of the proven features of the Peachbottom I reactor, the Fort St. Vrain HTGR core, and Oberhausen II turbomachinery. The major unique feature is the use of an indirect power cycle, with heliumto-helium intermediate heat exchangers. Cost estimates are summarized which indicate that the ability of the gas turbine cycle to discharge waste heat at a useful temperature gives the HTGR/GT system a significant advantage over nuclear and fossil-fired Rankine systems even though it is inferior to LWR systems on an electric-only basis. The fossil-fired gas-turbine total-energy concept is identified as its major competitor for the present application. Thesis Supervisor: Michael J. Driscoll Associate Professor of Nuclear Engineering Title: