Signal East coast transmission lines due at end-2027 would briefly lift Korean coal power in 2028 before a renewed decline

Summary

Under current government and KEPCO plans, the two east coast transmission lines to the capital region are expected to be completed at the end of 2027. Until then, expanding nuclear and renewable output and persistent transmission limits tighten restrictions on coal plants, cutting coal for power from 66.6 million tonnes in 2025 to about 51 million tonnes in 2027. When the 8 GW lines start operating in 2028, curtailment eases sharply, coal generation and coal for power rise by about 28 and 26 percent, and utilisation recovers from 40 to about 53 percent. After 2028 more solar and new nuclear units tighten restrictions again, with coal generation falling by around 11 percent a year and coal demand for power declining at double-digit rates. Retiring about 9.0 GW of coal capacity under the fuel-switching plan, from 40 GW to 31.1 GW, is not expected to be the main cause of lower coal demand because utilisation stays low.