In one line
Solar revenue in Korea has two parts, the System Marginal Price (SMP) paid for the electricity and the Renewable Energy Certificate (REC) issued for generating it renewably; the mainland SMP averaged KRW 133.79/kWh in July 2026, and the REC spot market averaged KRW 71,313/REC on 20 August 2026.
SMP, the price of the electricity itself
The System Marginal Price (SMP) is the wholesale price of one kWh, set hour by hour on the Korea Power Exchange (KPX) wholesale market. It is the base rate a solar operator receives for the power it sells, and it moves mainly with LNG fuel costs and electricity demand. The mainland and Jeju are calculated separately.
| Period | Mainland SMP (KRW/kWh) | Note |
|---|---|---|
| December 2025 | 90.43 | Lowest of the past 12 months |
| March 2026 | 110.03 | Recovering |
| June 2026 | 114.11 | — |
| July 2026 | 133.79 | Sharp rise as heatwave demand lifted load |
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SMP swings hard with the season and with fuel prices. It rose about 48% in seven months, from around KRW 90 per kWh in December 2025 to around KRW 133 in July 2026. That volatility is why long-term projects do not rely on SMP alone, and instead lock the rate in through a long-term fixed-price contract or a PPA.
REC, the certificate that says it was renewable
A Renewable Energy Certificate (REC) is proof that electricity was generated from renewables. One REC is issued per MWh generated, multiplied by a weighting set by the type of installation. Operators sell these certificates to obligated suppliers, and that income is separate from SMP.
On the 20 August 2026 trading day, the REC spot market averaged KRW 71,313, closed at KRW 71,300, and traded 281,855 RECs. The July 2026 monthly average was around KRW 71,555 on the mainland and KRW 81,776 on Jeju.
So what does that add up to
On the spot market, total revenue is SMP × energy yield, plus REC sales. Both prices move, which makes a 20-year projection hard to stand behind. That is why many operators take a long-term fixed-price contract, which fixes the combined SMP-and-REC rate for 20 years.
In the first fixed-price auction of 2026, the ceiling was KRW 147,686/MWh on the mainland and KRW 152,092/MWh on Jeju — about KRW 147.7 and KRW 152.1 per kWh. An award fixes the rate within that range for 20 years.
From 2027 this changes
With the amendment converting the RPS into a contract market passing the National Assembly on 20 August 2026, government materials show REC issuance for new installations stopping from 2027. From then on, a new project earns its revenue by winning an award in the competitive-bid contract market or by signing a direct PPA.
A generation information certificate is being created in place of the REC. It cannot be bought or sold; it exists for policy purposes, such as evidencing RE100 compliance or filing with a local government. For new projects, in other words, the business of selling certificates for income disappears.
Sources
- · Korea Power Exchange (KPX) monthly System Marginal Price and REC spot market. Verified 2026-08-22.
- · Korea Energy Agency, 2026 first solar long-term fixed-price contract competitive auction notice no. 2026-23 (2026-07-16)
- · Reporting on the New and Renewable Energy Act amendment passing the National Assembly plenary (2026-08-20 to 21)
This article is drawn from public sources available at the time of writing and is for reference only. Rules and market prices change. It cannot be used as the basis for an investment or contract decision.