Korea Power Exchange Opens 3rd ESS Central Contract Market
The Korea Power Exchange (KPX) opened its 3rd ESS Central Contract Market on September 30, 2026, offering 1180 MW (7080 MWh) of capacity. This round introduces new non-price evaluation criteria for land-based projects and a 25-year contract option for Jeju, signaling a shift in market priorities.
Our take
Who is best placed in Korea's third battery storage central contract market, on the mainland and Jeju?
In Korea's third storage central contract market, mainland bidders with sites near substations rated as relieving overload gain most, while Jeju bidders choose between a fully contracted 25-year route and a partly merchant 15-year route.
Price and non-price scores still weigh equally, so a favoured substation helps only bids already competitive on price, and KPX will assess substations qualitatively. On Jeju, whether a technology can sustain 730 cycles a year for 25 years decides which route a bidder can take.
What the source says
- The deadline for proposal submission is November 4, 2026.
- Supporting documents must be submitted by 3 PM on November 11, 2026.
- KPX plans to evaluate proposals and announce preferred bidders in mid-November 2026.
- The land market's non-price evaluation now includes a criterion for 'substations with significant grid overload mitigation effects'.
- Korea Power Exchange KPX will qualitatively assess substation-specific grid operation status and KEPCO's grid reinforcement plans and their effects for land-based projects.
- Industry official An industry official stated that quickly re-securing land near favorable substations and revising business plans is critical for the land market's success.
- Lee Ja-gyeom KPX Lead Market Team Manager Lee Ja-gyeom explained that Jeju's 25-year contract requires multi-charge, long-life facilities capable of 2 cycles per day (730 cycles annually) to address high wind power curtailment.
- Businesses that secured land based on previous 2nd market criteria may find their chosen substations no longer receive favorable evaluations in the 3rd market.
- Industry The industry interprets the 25-year, 2-cycle daily contract for Jeju as a move to favor non-lithium ESS due to limitations of existing lithium-ion batteries.
- Korea Power Exchange KPX stated that the increase in ESS volume is a proactive measure to prepare for the expansion of renewable energy outlined in the 12th Basic Plan for Long-term Electricity Supply and Demand.
- Korea Power Exchange KPX denied that the new Jeju contract was designed to favor specific battery types.
- The 3rd market capacity includes 6600 MWh for land and 480 MWh for Jeju.
- The price and non-price evaluation ratio remains 50:50, unchanged from the 2nd market.
For investors — Contracted storage investors should check how a held mainland site's substation ranks under the new overload-relief criterion before bidding, and on Jeju should bid the 25-year option only with evidence the technology sustains twice-daily cycling for the full term.
Merchant storage investors and optimisers should value Jeju's 15-year option on Jeju price spreads and the optimiser's own charge and discharge bids, since it is the only part of this round with market exposure.
Watch: KPX's announcement of preferred bidders for the 3rd ESS Central Contract Market in mid-November 2026.
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