Abstract: The invention is directed to a method and apparatus for providing a single-cycle boiling moderator-coolant nuclear reactor which accommodates changes in demand with a turbine generator on direct governor control. Current single-cycle boiling moderator-coolant nuclear reactors employ turbine generators that are slaved to the reactor. This arrangement is dictated because of inherent response limitations of the single-cycle boiling moderator-coolant nuclear reactor. The system of the present invention diverts steam from steam consuming normal auxiliary plant equipment to maintain reactor pressure when a rapid increase in turbine power demand is made such as during a daily load following or a frequency regulation change in demand. This allows the turbine generator to be placed on direct governor control. Rapid positive or negative demands accepted by the turbine cause a decrease or an increase in the pressure of the reactor.