GS Entec's monopile for offshore wind power projects / Courtesty of GS Entec

GS Entec announced Thursday that it produced its first monopile for a domestic offshore wind power farm, marking the first time for a Korean company to supply such a wind turbine substructure for a domestic offshore wind project surpassing 100 megawatts.

According to the company, the monopile is the first out of 64 monopiles it will supply to a 365-megawatt offshore wind project in Nakwol area in waters off Yeonggwang County, South Jeolla Province. The monopile measures 71.2 meters in length, 7.5 meters in diameter and weighs 895.6 tons, capable of supporting a 5.7-megawatt turbine.

By September next year, GS Entec will supply 64 monopiles under a 200 billion won ($144.3 million) contract signed with the project's operator last year.

A monopile is a cylindrical structure made by welding large steel plates and serves as a support for wind turbines. Compared to substructures such as tripods and jackets, monopiles excel in terms of shorter production periods and lower costs.

The rollout came after GS Entec signed an exclusive technology licensing agreement last year with Sif Netherlands BV, the world's leading company in monopile offshore wind substructures.

The agreement was in line with the company's efforts to transform its business portfolio from petrochemical equipment for oil refining and petrochemical plants to eco-friendly energy equipment.

Following the agreement, the company has been making investments totaling 300 billion won, including 214 billion won for introducing Sif's latest automated equipment at its plants.

"The monopiles supplied for the project will be a cornerstone in the company's related businesses," a GS Entec official said. "We plan to supply monopiles for ongoing offshore wind projects in South Korea and Japan."

In the global wind power market, project operators are increasingly preferring monopiles as the substructure for wind turbines, thanks to their short installation time and cost efficiency. However, unlike European nations, Korea, Japan and other Asian countries are still in the early stages of introducing monopile substructures for wind turbines.

Since monopiles are expected to maintain their integrity underwater for at least 20 years — the average lifespan of a wind turbine — and have limitations in their movement, the vicinity of the wind power supply chain is crucial for power companies, according to industry officials.