The MSR is part of the Generation IV programme (The US Generation IV Implementation Strategy, 2003). In this design, the fuel is a liquid mixture of sodium, zirconium and uranium fluorides. The system is low pressure, with the coolant outlet temperature around 700°C. The power for the reference plant is 1000 MWe. It is a flexible system for actinide destruction. The economics are less favourable because of a large number of support systems for the maintenance of fuel and coolant. The system will require significant advances in chemistry plant design before it can realise a more mature design. The MS system will largely be for electricity production and plutonium and minor actinide destruction. Some example reactor types are given in Table 12.7.