Comparing Cycling and Opportunity Values of Long-Duration Energy Storage in United States

The intermittency and seasonal pattern of renewable energy resources requires the ability to economically store the bulk of energy over long timescales. Long-duration energy storage is a promising solution to enable high renewable penetration in a low-emission electricity system, which can alleviate the longterm temporal mismatch of electricity demand and renewable resources abundant period. This paper analyzes how energy storage duration and location affect the cycling pattern and opportunity value of long-duration storage as a price taker in real-time market arbitrage. We use a dynamic programming approach to optimize the storage operation on an annual basis, and obtain the opportunity value of the energy stored. We perform the analysis over storage duration from one day to one month using historical data from California, New York, and Texas. Our results show significant locational differences among storage utilization that are jointly contributed by different resource mixes and congestion in the considered price zones. Long-duration energy storage is likely to be under-utilized in existing power systems, and deployment of long-duration energy storage must be carefully coordinated with renewable deployments.