Buk-Dangjin - Godeok

The Buk-Dangjin - Godeok HVDC project is a power transmission infrastructure development in South Korea, designed to enhance the country's electrical grid and meet growing energy demands. This high-voltage direct current (HVDC) transmission link connects the Dangjin power plant in the west of South Korea to Godeok, east of Seoul, spanning a distance of 33 kilometers across the Asanman Bay.

Project Overview

The project was implemented in two phases, with a total capacity of 3 GW upon completion. The first phase, commissioned in December 2020, established a 1.5 GW asymmetrical monopole HVDC link. The second phase, commissioned in 2024, added a further 1.5 GW, forming a bipole configuration with a total power capacity of 3 GW at ±500 kVDC.

Technical Specifications

The Buk-Dangjin - Godeok HVDC link operates at 500 kV and utilizes underground cables for transmission. This HVDC system employs Line Commutated Converter (LCC) technology, which offers advantages in terms of power control and fault current interruption. The project includes two converter stations, one at Bukdangjin and another at Godeok, equipped with valves, cooling systems, converter transformers, filters, switchyards, and control systems.

Strategic Importance

This HVDC link plays a crucial role in South Korea's energy infrastructure for several reasons. It enables efficient power transmission from the Dangjin power plant to the densely populated Seoul metropolitan area, which represents about 40% of South Korea's energy demand. The project bypasses a 100 km detour that an alternating current (AC) scheme would have required, avoiding the construction of new overhead lines and reducing environmental impact. It enhances grid stability and reliability by providing fast and accurate power flow control, effectively preventing the spread of blackouts. The HVDC technology reduces transmission losses by approximately 30% compared to conventional AC lines, making it more economical and environmentally friendly.

Project Development

The Buk-Dangjin - Godeok HVDC project is a collaborative effort between Korea Electric Power Corporation (KEPCO) and GE Power, through their joint venture KAPES. Construction of the first phase began in 2018 and was completed in 2020. The second phase became operational in 2024

Broader Context

This project is part of KEPCO's larger strategy to reinforce South Korea's electrical network and develop the North East Asia Supergrid. The Supergrid initiative aims to connect South Korea's power grid with neighboring countries, enabling the import of renewable energy from regions like the Gobi Desert and Western China, and facilitating power exchange among neighboring grids.

Impact and Benefits

The Buk-Dangjin - Godeok HVDC link will significantly improve power supply to the Pyeongtaek semiconductor complex and the southern Seoul metropolitan area. It will also contribute to the success of new investments in advanced industries and support balanced national development. The project demonstrates South Korea's commitment to modernizing its power infrastructure and adapting to the growing energy needs of its high-tech industries and urban centers.