To support the safe and efficient operation, flexible and adaptive regulation capabilities of a high proportion of new energy power systems, it is necessary to simultaneously develop large-scale pumped storage energy. To scientifically and accurately quantify the benefits of pumped storage capacity with and without the influence of new energy, a concept of pumped storage capacity benefits is proposed；Secondly, a comprehensive analysis is conducted on the impact of the proportion of new energy in-stalled capacity and output characteristics on the efficiency of pumped storage capacity in different scenarios. In order to consider the impact of uncertainty in new energy on capacity efficiency. Further determine the thermal power start-up demand and pumped storage capacity benefits considering the new energy power support capacity based on meeting the power supply demand at 95% of the time；Finally, based on the planning situation of a certain region, compare and analyze the pumped storage capacity benefits corresponding different energy storage time. The research results indicate that this method can scientifically guide the construction and opti-mization of operation strategies for the scale of future pumped storage demand in the medium to long term.