Nuclear steam power plants (NPP) are characterized by low efficiency, compared to steam power plants using fossil fuels. This is due to the relatively low temperature and pressure-throttling conditions of the NPP compared to those using fossil fuel. The light water pressurized water reactor (LW PWR) commercially known as AP600 was suggested for Kuwait cogeneration power desalting plant (CPDP). It has 600 MW nominal power capacity and 33% overall efficiency. Meanwhile, the Kuwaiti Ministry of Electricity and Water (MEW) installed plenty of gas turbines (GTs) to cover the drastic increase in the peak electrical load during the summer season. Combining some of these GTs with the AP600 can increase the capacity and efficiency of the combined plant, compared to either the CT open cycle or the NPP separate plants. This paper investigates the feasibility of utilizing the hot gases leaving the CT to superheat the steam leaving the steam generator of the AP600 NPP, as well as heating the feed water returning to the steam generator of the NPP condenser. This drastically increases the power output and the efficiency of the NPR Detailed modifications to the NPP power cycle and the resulting enhancement of its performance are presented. (C) 2010 Elsevier Ltd. All rights reserved.