System value and utilization performance analysis of grid-integrated energy storage technologies in Japan

Deploying utility-scale storage systems is expected to play a critical role in improving energy flexibility and economic performance considering rising variable renewable energy penetration. However, existing studies take the impacts of storage duration times and changes in the real-world electricity market into account less. This study develops a framework to evaluate and compare the opportunity value of different storage technologies as a price taker aiming at maximizing the arbitrage profit. Firstly, long-term operational data of real-world grids were collected, and results indicate that rising penetration of renewable energy generation increases the inter-annual volatility and decreases the average value of spot prices. Comparative results verified that the storage roundtrip efficiency, duration time and variation of spot prices impacted the storage arbitrage profits and utilization rates significantly. The rising volatility of spot prices is largely driven by the rapid expansion of renewable energy generation, adds more opportunity value to the storage system dispatch process, and amplifies the influence of storage duration. The results present the potentiality of deploying power to hydrogen as long-duration storage to deliver economic benefits by exploring the variations of the spot prices. Overall, a full understanding of how the role of storage systems changes provides insight into options for storage planning of renewable-dominated electricity systems.

Automated summary

Deploying utility-scale storage systems is crucial for improving energy flexibility and economic performance in the face of increasing renewable energy penetration. However, previous studies have not adequately considered the effects of storage duration and changes in the electricity market. This study develops a framework to evaluate and compare different storage technologies in terms of their arbitrage profit potential, taking into account factors such as roundtrip efficiency, duration time, and spot price variation.