[en] A number of different Power system architecture options that include all nuclear, all non-nuclear, and a combination of the two, were defined to satisfy power requirements for the first lunar outpost (FLO). The Life Cycle Costs (LCCs), including development, production, and transportation costs, of these architectures were determined and the sensitivity of the LCC to parameters such as transportation cost and the radioisotope fuel costs was evaluated. The results indicate that the LCC can be very sensitive to the variation in transportation cost and radioiosotope fuel cost. The relative attractiveness of different candidate power system architectures should also be based on several other evaluation criteria such as safety, performance, risk, commonality, and growth potential. A simple methodology to determine relative ranking of the candidate power system architectures based on these evaluation criteria is suggested