Natural gas, imported coal and nuclear power plants are compared in terms of long-term (1996-2010) production economy in this study. Calculation of an accurate unit production cost of a power plant is generally a hard task. Especially in countries without any previous production experience, unit production cost calculation becomes more difficult. Therefore, it is difficult to determine the "best" plant alternatives to make a judgment. Owing to the subjective and incomplete data, preference of alternatives is modeled with fuzzy preference relation. Three preferences models are developed to evaluate the nondominance set from a set of alternatives for further development. During the applications of preference models, if alternatives are outranked by other alternatives, they are removed and are not taken into consideration. The approach developed is very much suited for applications in the fuzzy and uncertain environment. (C) 2000 Elsevier Science B.V. All rights reserved.