Abstract: With the high-penetration renewable energy integration and high-voltage DC feeds, the insufficient frequency response capacity leads to the increasing demands for the flexible regulation resources in the power grid. This paper analyzes the multi-dimensional operation bottlenecks of a receiving-end power grid in East China. Firstly, the operational restriction indices are introduced to obtain multi-dimensional operation bottlenecks that affect the power balance and safe operation of the system, and an operational bottleneck identification model is established with the multi-dimensional constraints such as the spinning reserve capacity and the fast frequency regulation reserve capacity. Then, the identified bottleneck scenarios are summarized according to their operational restriction indices. By considering the duration requirements of the energy storage in different bottleneck scenarios and comparing the relative economics of various solutions to eliminate the operational bottleneck scenarios with economic technical parameters, the economic application scenarios of the energy storage and the energy storage demand are obtained. Finally, an example indicates that the electrochemical energy storage is more economical than the pumped hydro storage and the conventional generation in eliminating the bottlenecks of the frequency regulation reserve capacities.