South Korea is set to open a large-scale market for energy storage systems (ESS), with total investment expected to reach approximately $724 million. The move comes as part of efforts to stabilize the national grid and accommodate growing volumes of renewable energy.
On May 22, South Korea’s Ministry of Trade, Industry and Energy (MOTIE) announced plans to introduce 540 megawatts (MW) of ESS capacity to alleviate grid congestion and reduce power curtailment in both inland and Jeju Island regions.
ESS functions as an “electric reservoir,” storing excess electricity generated during low-demand periods and discharging it when demand rises-enhancing overall grid flexibility and reliability.
According to MOTIE, the government will procure 500 MW of ESS capacity for inland areas and 40 MW for Jeju Island through a central market bidding process. This plan aligns with the targets outlined in the 11th Basic Plan for Long-Term Electricity Supply and Demand finalized earlier this year.
Given that each ESS system is designed to store energy for six hours a day, the actual installed storage capacity is expected to reach 3,000 megawatt-hours (MWh) inland and 240 MWh in Jeju-enough to power approximately 8,600 households for a full month.
This marks the first time ESS installations of this scale will be deployed nationwide under the operational direction of the Korea Power Exchange. A smaller-scale pilot project involving 65 MW of ESS was previously initiated in Jeju in August 2023.
A MOTIE official explained that seasonal drops in electricity demand during spring and autumn have led to grid saturation and forced power generation curtailments-especially for coal and thermal power plants. The introduction of ESS is expected to mitigate these issues and reduce social conflicts over compensation for halted operations.
Government sources estimate the total construction cost for the ESS systems to be around $724 million. The final selection of bidders is scheduled for July and will be based on a comprehensive evaluation that includes not only price but also grid contribution, safety, and technological value.
Industry insiders expect domestic battery giants such as LG Energy Solution, SK On, and Samsung SDI to be among the top contenders, particularly given the evaluation criteria include domestic industry involvement and recyclability of used batteries.
“ESS installations will enhance power grid stability despite the intermittency of renewables,” a MOTIE spokesperson said. “We also expect a noticeable reduction in renewable energy curtailment frequency.”
