Study on Thermal Efficiency of SCWRs

Abstract

The vast majority of current Nuclear Power Plants (NPPs) are equipped with light- and heavy-water-cooled reactors. Unfortunately, these NPPs have relatively low thermal efficiencies compared to those of thermal power plants. Since, many countries worldwide are developing water-cooled Small Modular Reactors (SMRs), it is a very important task to increase the thermal efficiency of water-cooled-reactors NPPs. Following the example of coal-fired power plants, SuperCritical Water-cooled Reactors (SCWRs) are one option for increasing thermal efficiency. The current paper presents a study on effects of various parameters on thermal efficiency of SCWRs. Specifically, steam inlet-turbine temperature and pressure are investigated using the IAEA DE-TOP program. It was found that the steam inlet-turbine temperature has a larger impact on thermal efficiency than does pressure. Moving from subcritical-pressure Rankine cycle to SCP Rankine can increase thermal efficiency up to ~12%. Increased efficiency can have environmental and economic benefits.