Wando-Dongjeju 3

In 2016, as part of its Paris Agreement commitment to reduce carbon dioxide emissions by 37 percent, the Korean government announced that Jeju Province would become carbon-free and powered entirely by renewable energy by 2030.

Jeju is one of the country’s nine provinces and its largest island. Renowned for its beauty and volcanic sand beaches, this subtropical paradise is home to 620,000 people and one of East Asia’s most popular holiday destinations, hosting around 15 million tourists each year. 

Like many islands, Jeju receives much of its power from the mainland. Two high voltage direct current (HVDC) links already transport 700 megawatts of electricity from the peninsula 100 kilometers away, but more is needed.

Korea Electric Power Corporation (KEPCO), the country’s largest electric utility, is therefore building a third HVDC interconnection to provide an additional 200 MW of power to boost supply and stabilize the island’s power grid.

After considering various solution proposals, KEPCO chose Hitachi Energy to provide the new link’s most important components – the two converter stations – which convert the power from AC to DC on the mainland for transfer by subsea DC cable, then back to AC on JeJu for distribution.

Crucially, the Hitachi Energy HVDC solution based on voltage source conversion (VSC) will also enable KEPCO to operate the island’s other interconnections more efficiently, a key feature of the VSC technology. This will stabilize the grid and minimize the risk of outages.

The Jeju 3 link is the first HVDC interconnection in the Republic of Korea using the VSC technology.