Design options for a liquid metal reactor coupled with an AMTEC unit

An analysis of design options for a liquid metal-cooled nuclear reactor (LMR) coupled with an alkali metal thermal-to-electric converter (AMTEC) is presented. In order to select the optimal design solution, the following concepts were analyzed: direct coupling with expanders, indirect coupling with expanders, and indirect coupling with boilers. The paper discusses the advantages, drawbacks and main plant characteristics of these designs. The results show that the indirect coupling with alkali metal boilers in a pool configuration is the most promising option. When sodium and potassium are employed as primary and secondary working fluids, this design could achieve a net efficiency of about 28.3% at an average core outlet temperature of 1050 K and using the near term AMTEC technology.