Thermal efficiency alone is an insufficient measure of the profitability requirement that electric power companies have on their power plants, in particular with the advent of deregulated electricity markets. In the present paper, this issue is illustrated with a study on the combined-cycle plant, where the benefit of various turbine entry temperatures and various materials for the first stage of the gas turbine is studied. The deviation in net present value is calculated, and it is shown how the possible profit to be made from more advanced materials and cooling is highly dependent upon electricity and fuel prices, whereas, the intervals for blade replacement during planned stops have a smaller impact on power plant profitability.This paper was presented at the ECOS'00 Conference in Enschede, July 5-7, 2000