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Many large systems accidents resulting in forced shutdown of generating sources and loss of power to them occur in world practice. This is an urgent question for nuclear power plants because the reactor core must be cooled down. Using data obtained by Atomenergoproekt for the No. 4 unit of the Balakovo NPP, it has been shown that blackout events make the greatest contribution to the likely core damage rate (51.4%).Currently, in the event of a blackout diesel generators are used to supply power for cooling reactors in an emergency [1]. Power for the main circulation pumps and process water pumps is lost, which results in higher pressure in the second loop, actuation of BRU-A and safety valves of steam generators and, correspondingly, steam dumping into the atmosphere. Steaming dumping through BRU-A can cause coolant losses and auxiliary failures resulting accidents. In the event of a blackout, the reliability of the diesel generations during startup and operation is important. A reactor cools down during an accident, which requires auxiliary inputs to restore its serviceability. The residual heat released in the reactor core is not used during cool-down, while an appropriate design modification of the power-generating unit would make it possible to use this heat to generate electricity for the internal needs of the power plant.To prevent losses of the working body through the second-loop safety valves and to avoid the associated negative consequences, it is best to cool the reactor in a regular regime without actuating the fast reduction setup with steam dumped into the atmosphere (BRU-A), i.e., keep the main circulation pump, electric water pump, process-water circulation pump and condensate pumps in operation. Then, all the main circulation loops will be operating on a minimal load. On this basis, the power required for internal needs of this regime for VVER-1000 is 11 MW [2].One method in the regular operating regime is to cool the reactor by means of an auxiliary turbo setup supplying power for internal needs. This setup operates on the steam generated by energy from the residual heat release and burning hydrogen in oxygen. The auxiliary turbo setup is a relatively low capacity steam turbine (satellite or autonomous with respect to the main turbo setup), which is synchronized with the generator of the main turbo setup for distributing power from the auxiliary capacity into the grid.In the present communication, to increase the efficiency of the continually operating auxiliary turbine, we consider a scheme in which the unused electric energy is accumulated in the form of hydrogen and oxygen during the nighttime offpeak hours and used to generate and superheat steam flowing to the auxiliary turbine during the peak hours [3]. The auxiliary turbine and hydrogen system can be placed outside the NPP compound.During the day, the auxiliary steam turbine setup is used to generate the peak load electricity, and its nighttime load is reduced to a minimum. In the event of an emergency shutdown of the reactor and blackout ...