Economic Method for Energy Storage Planning of Large New Energy Bases in the Electricity Spot Market

With the continuous advancement of new energy base construction， it is crucial to consider the impact of these bases on the operation of the receiving-end electricity spot market. This paper proposes a two-layer economic analysis model for energy storage planning in new energy bases under market conditions. The lower layer of the model simulates the long-term electricity spot market at the receiving end， integrating security-constrained unit commitment and economic dispatch as core components. The upper layer focuses on the optimal scheduling model of the new energy base with the objective of maximizing its revenue. Given the complexity of the two-layer model， an alternating iteration method is employed to solve the problem. On this basis， the economic impact of different energy storage types on new energy bases is analyzed through payback period assessments， leading to optimal energy storage capacity planning. The effectiveness of the proposed model and algorithm is validated through a practical grid case study， which demonstrates that compressed air batteries have the most significant impact on enhancing the revenue of large-scale new energy bases. Meanwhile， 2-hour lithium batteries exhibit the lowest investment payback cost， and an energy storage capacity of approximately 1000 MW is found to be optimal.