Supercritical-Pressure Water Nuclear Reactors

The concepts concerning a nuclear reactor cooled by water at supercritical pressure (25 MPa) are presented. The system has one loop. Superheating the coolant to 530°C makes it possible to obtain ~44% efficiency. On the basis of the neutron spectrum, the reactor is a fast resonance reactor. The tight array of fuel elements and the lower water density make it possible to obtain plutonium fuel breeding ratios ~0.94. The problems which must be solved to build such a reactor are discussed.