Transmission Grid

The Electricity Market Operation Rules define the transmission grid as the transmission lines, transformers, reactive power compensation equipment, protective devices, energy storage and similar assets owned and managed by electricity businesses. Power from plants travels over the transmission grid to substations and then over the distribution grid to each user.

In Korea, KEPCO owns and maintains the transmission grid, while KPX runs grid operation and dispatch. Transmission and distribution operators must let other electricity businesses use their facilities without discrimination. The law calls a mismatch between generation capacity and transmission capacity a 'transmission constraint'.

News-reading tip: stories about delays in building transmission lines lead to grid constraint and curtailment issues. Also check whether a story means the high-voltage transmission grid or the distribution grid that reaches neighborhoods.