Combined with the characteristics of rapid switching between charge and discharge and convenient power generation adjustment of energy storage system (ESS), a clean energy grid-connected power system risk quantification and security benefit evaluation plan considering energy storage power stations is proposed. Firstly, combined with the charging and discharging characteristics of ESS, the necessity of maintaining the medium and long-term safe production, reliable operation of the power grid and the cooperative promotion of clean energy consumption mechanism is explained. On this basis, combined with markov chain monte carlo (MCMC), an emergency state analysis model and a risk assessment model considering the flexible charging and discharging strategy of ESS are established. Secondly, an evaluation plan for the comprehensive benefits of the energy storage power station was designed by economic comparison analysis. Finally, the revised IEEE- 6 node test system is taken as an example to demonstrate the effectiveness and advancement of the proposed model and scheme.