Two multi criteria decision-making algorithms of fuzzy logic and grey incidence approach are used to choose the best prime mover for a micro-CCHP system, to be used in a residential building, in five different climates. Four criteria of technological, economical, environmental and social, and sixteen sub-criteria are used in the decision-making process. Four main options for the prime mover include the conventional separate production, internal combustion engine, micro-gas turbine and sterling engine. Other options such as the gas turbine, steam turbine and fuel cell are omitted in the pre-design steps. The decisions made by the fuzzy logic and the grey incidence approach confirm each other and they give the same results for all the climates. The two decision-making methods propose that the best to worst prime movers are the internal combustion, sterling engine, conventional separate production and micro-gas turbine. The results show that the climate difference changes the magnitude of the technological and the overall evaluation indexes but the final decision remain unchanged for all the climates. In addition, the research shows that the fuzzy logic and the grey incidence approach are easily programmable and give reasonable answers to the decision-making problems. (C) 2012 Elsevier B.V. All rights reserved.