Hybrid Energy Storage Systems

Korea Electric Power Corporation's HESS (Hybrid Energy Storage System) uses advanced technologies to improve efficiencies and overcome the large amount of space and strict geological constraints required for some types of energy storage. According to Korea Electric Power Corporation, the Hybrid Energy Storage System “improves the low energy storage efficiency (Round-Trip Efficiency, RTE) of 50~70% typically associated with conventional Compressed Air Energy Storage (CAES), and overcomes the geological constraints and the drawback of large space requirements for installation of Pumped Storage Hydropower (PSH).”

This system, developed to mitigate grid instability caused by renewable energy generation and store utility-scale over-generated power, is a CES 2026 Innovation Awards Honoree in the Sustainability & Energy Transition category.