The following is a summary of the main findings of this study:

• There is a plethora of data, empirical correlations and simple models for heat transfer and pressure drop published in the literature on the use of many supercritical fluids, mainly for simplified test sections. We have compiled and reviewed as much of the information as possible (in general, about 650 literature sources), and have provided all the key references and inter-compared the experimental and theoretical approaches. The data largely cover all the ranges of interest, but of course for mainly commercial reasons some design specific information is missing from the open papers and reports.

• There are hundreds of fossil power plants in the world using supercritical conditions (thermal parameters: water pressure of up to 25 – 30 MPa, turbine inlet temperatures of up to 625°C (but mainly lower than 600°C) and power output of up to 1400 MW_e), which have been successfully operated for many years. Their main advantage is high thermal efficiency of up to 45% – 53%. The demonstrated experience in their design and operation is very helpful for current developments in fossil-fired units and in nuclear-powered reactors cooled with supercritical water and provides useful benchmark data.

• After a 30-year hiatus, because of the fossil experience and the need to improve the overall cycle thermal efficiency, the idea of developing nuclear reactors cooled with supercritical water became attractive again, and several countries (Canada, Germany, Japan, Russia, and the USA) have started to work in that direction. However, none of these concepts is expected to be implemented in practice before 2015 – 2020.