Korea Electric Power Corporation (KEPCO), led by President& CEO Kim Dong-cheol, announced that it held a completion ceremony for theWando–East Jeju HVDC construction project on 6 March at the East Jeju ConverterStation.

This event was held to celebrate the successful completionof South Korea’s first voltage-source HVDC (High-Voltage Direct Current)project connecting the mainland and Jeju Island, marking a significantmilestone in stabilising Jeju’s power grid.

Due to its geographical characteristics, Jeju operates as asmall-scale, isolated power system, separate from the mainland grid. However,rapid growth in tourism and regional development has led to a surge inelectricity demand, making it increasingly difficult to maintain a stable powersupply with local generation facilities alone.

In response, the South Korean government included theWando–East Jeju HVDC project in its 5th Basic Plan for Electricity Supply andDemand in 2010. This marked the third HVDC connection between the mainland andJeju, following the Haenam–Jeju HVDC in 1998 and the Jindo–West Jeju HVDC in2014.

KEPCO commenced the project in December 2016 andsuccessfully installed the submarine power cable in December 2023. Aftercompleting the installation and testing of conversion equipment in September2024, the system underwent two months of trial operations to verify stability,leading to its official completion on 29 November.

With the completion of the Wando–East Jeju HVDC project,KEPCO has established a more stable power supply between the mainland and Jeju. 

This project connects Wando and Jeju via a 98km submarinepower cable, increasing Jeju’s power import capacity from 360MW to 600MW. As aresult, Jeju’s power reserve margin has significantly increased from 14.3% to30.8%.

President Kim Dong-cheol stated:

"Building on the experience gained from this project,we will accelerate the localisation of large-scale HVDC technology and continueto strengthen our track record in energy innovation. I am confident that theWando–East Jeju HVDC will not only enhance Jeju’s power grid stability but alsocontribute significantly to the government’s carbon-free energytransition."

Furthermore, with the increased HVDC power supply capacity,KEPCO expects to reduce its reliance on expensive locally generatedelectricity, leading to annual savings of approximately KRW 20 billion in powerpurchase costs. Additionally, the project has reinforced Wando’s power supplyinfrastructure by establishing a ring network, thereby enhancing reliability inone of South Korea’s most power-vulnerable regions.