Currently, the Unified Energy System of Russia has a tendency to increase the deficit of peak and semi-peak capacities with a simultaneous increase in the number of NPP which requires the participation of NPPs in a variable part of the schedule electrical loads. In addition to the economic need to maintain the installed capacity utilization rate at a high level, there are technological limitations for maneuvering characteristics for NPPs. The authors have developed an approach to solving this problem based on combining with an environmentally friendly energy source – an autonomous hydrogen complex which includes heat accumulators and an additional multifunctional low-power steam turbine installation. The developed power complex can also provide reliable redundancy of power supply of NPP own needs in the event of a total station blackout. The paper carries out the evaluation of the technical and economic parameters of the main equipment of the autonomous hydrogen complex required for combination with a two-unit NPP with a VVER-1000. Based on the assessment of inflation indicators of the Russian economy over the past 11 years, three options have been identified for fuel cost and tariff rates for electricity (capacity), as well as the size of operating costs, including depreciation in the main equipment, taking into account current pricing principles. As a result, the values of accumulated net present value were obtained depending on the ratio of the cost of semi-peak and non-peak electricity tariffs at different inflation rates. We have taken into account the positive economic effect of reducing the risk of damage to the reactor core, replacing the construction of gas turbines as a maneuverable source of electricity in the power system, and increasing the income of the federal budget of the Russian Federation from saving natural gas. The economic conditions of competitiveness of the proposed approach to improving the maneuverability and safety of NPP are determined. The highest economic efficiency is achieved with the maximum projected inflation which is associated with the maximum discount rate and high rate of growth of electricity tariffs. Reducing the risk of damage to the core allows us to provide the competitiveness of the proposed approach in all considered variants of inflation and the ratio of electricity tariffs.