updated 2026-10-22
SMP (System Marginal Price)
System Marginal Price · wholesale power price · marginal price
SMP is the energy price set for each trading hour in the power market. It is the highest generation price among the generators eligible to set the price in that hour.
SMP (System Marginal Price) is the hourly energy price defined in the Electricity Market Operation Rules. It is quoted in KRW/kWh and calculated separately for the mainland and Jeju.
Using the day-ahead generation schedule, KPX computes a generation price for each generator and takes the highest one among price-setting-eligible generators as that hour's SMP. Generators in Korea do not bid prices. It is a cost-based pool: prices come from variable costs pre-assessed by the Cost Evaluation Committee. The 2025 annual average of the integrated SMP was 112.72 KRW/kWh.
News-reading tip: read a rise or fall in SMP mainly as a change in the fuel cost of the price-setting generators. SMP is the wholesale price paid to generators, so it does not move one-for-one with household electricity bills.
This describes the mainland market. Jeju has run a pilot real-time market and renewable bidding since June 2024.
Sources
- 전력시장운영규칙(2026-07-25 시행) 제1.1.2조 제3호(계통한계가격 정의)
- 전력시장운영규칙(2026-07-25 시행) 제2.4.2조(계통한계가격의 결정)
- KPX 2026 전력거래사 학습가이드 §2.1.1 전력거래시장 p.50–52, p.72
- 전력거래소, 「2025 전력시장통계」 표 1-5 계통한계가격(통합 SMP 연평균)
- 전력시장운영규칙(2026-07-25 시행) 제16.1.2조·제16.1.4조(제주 실시간시장·재생에너지 입찰제도)