This paper considers the probabilistic analysis of lifetime discounted costs of electrical energy if produced in coal-fired, gas-fired and nuclear plants entering in operation in Croatia (similar as is in neighboring European countries) versus the end of this decade. The calculation considers all relevant costs in the period of loan repayment and after this period to the assumed end of plant life. The cost data are defined by best-estimated lower and upper cost limits with a probability distribution within these limits. An important factor for comparison of costs is related to assumed limits of rates of fuel cost changes for considered power technologies during plant operation time (during a period approximately from 20 10 to 2040). These changes depend upon potential frictions in the fuel market in the considered period. The calculation is performed by using the Monte Carlo method (2000 calculations per technology) and STATS computer code. From the results of the simulations it can be concluded that the distribution of levelized bus bar costs for the combined cycle gas plant is in the range 4.5-8 US cents/kWh, with a most probable value of about 5.8 US cents/kWh; for coal-fired plants the corresponding values are 4.5-6.3 US cents/kWh and 5.2 US cents/kWh and for the nuclear power plant the corresponding values are in the range 4.2-5.8 US cents/kWh and a most probable value of about 4.8 US cents/kWh. In addition, the importance of considering the environmental impact of power plants and the application of corresponding external costs in the analyses of relative competitivity of power technologies is discussed. (C) 2003 Elsevier Ltd. All rights reserved.