As the government begins screening for offshore wind bids in the first half of 2026, the energy industry is voicing concern that foreign-made subsea cables that could be used for wiretapping and eavesdropping may be allowed. Because bidders can participate without designating a subsea cable supplier, they can select and install any company they want after winning, regardless of nationality. The government said it would protect Korea's offshore wind supply chain by introducing a security metric into the evaluation criteria, drawing attention to whether it will work as intended.
According to the power industry on the 12th, the Ministry of Climate, Energy and Environment started screening first-half offshore wind bids on the 11th. An official at the Ministry of Climate, Energy and Environment said, "We can't confirm the screening schedule," but added, "We will announce the selection results at the end of June."
Offshore wind competitive bidding is conducted in two rounds. According to the first-half wind fixed-price contract competitive bidding notice the Korea Energy Agency (KEA) released in March, 50 points are allocated to both round one and round two.
For offshore wind, the first-round evaluation metrics are resident acceptance (4 points), industrial and economic impact (22 points), base and maintenance (8 points), project progress (2 points), grid acceptance (8 points), and security (6 points). If a bidder passes the first round, the second round evaluates only the bid price (50 points).
The issue is that bidders do not need to decide which company will handle the offshore wind subsea cable when submitting applications. A wind industry official said, "A total of nine projects participated in the first-half offshore wind bidding, including a public-led model involving generation subsidiaries of Korea Electric Power Corporation (KEPCO)," adding, "Of these, five projects did not specify a subsea cable supplier."
Of course, if a bidder does not present a subsea cable supplier, it is likely to receive low scores in the industrial and economic impact, base and maintenance, project progress, and security categories of the first-round metrics. However, if it passes the first round, it could still be finally selected by offering a low price in the second round, which looks only at price. In that case, the offshore wind developer can select a subsea cable supplier at its discretion.
An official at the Korea Energy Agency (KEA) said, "If you bid without selecting a subsea cable supplier, you will receive the lowest score in that area," but added, "Even so, if selected, the company can set the supply chain as it wishes, sign contracts, and proceed with construction. Once selected, it is not a problem to use Chinese-made subsea cables."
◇ "Beyond the power grid to the information network"… offshore wind subsea cables could become tools for underwater wiretapping
Foreign-made subsea cables have emerged as a concern because the issue is directly tied to national security. The offshore wind grid consists of an internal network and an external network. The internal network connects offshore wind generators (turbines) to each other and to the offshore substation. The external network is the subsea cable that carries the electricity gathered at the offshore substation to the onshore substation where power is consumed.
The key among these is the external network. Offshore wind external networks include fiber-optic cables. They are needed to communicate with offshore substations and to detect problems in the cable in advance to prevent major accidents.
The problem is that fiber-optic cables can be used for wiretapping and eavesdropping. Fiber-optic cables transmit information as light, and when the cable is minutely bent, light leaks out. If a device that can secretly capture the light is installed during manufacturing or after installation of the subsea cable, military secrets and national data passing through territorial waters can be leaked.
This is because the light in fiber-optic cables is highly sensitive even to tiny vibrations, allowing detection of vibrations generated when submarines or warships pass near subsea cables. Analysts say that by analyzing such vibration data, it is possible to monitor in real time the movement routes of Republic of Korea Navy submarines.
A power industry official said, "Subsea cables do more than simply move electricity; they also transmit various data," adding, "Using foreign-made subsea cables is like spending our money to install foreign-made CCTV cameras and bugs, handing over the movements of our military and our energy control in one fell swoop."
The official added, "The scariest aspect of subsea cable wiretapping and eavesdropping is that, unlike computer hacking, it leaves no trace at all, so you may never know that you are being hacked."
◇ First test of the security metric after the "no selections" in 2025: will it block Chinese-made subsea cables?
Even though subsea cables are directly tied to the domestic supply chain and national security, the industry is watching the results of this bidding because, once selected as an offshore wind project, a pathway opens to use foreign-made subsea cables, including those from China. Moreover, this offshore wind bid could serve as a gauge of whether the government's newly introduced security metric works properly.
The government added a security metric to offshore wind bid evaluations starting in 2025. This followed growing supply chain concerns in the wind industry after a project that said it would use Chinese-made turbines was selected in the 2023 offshore wind bidding.
The government then institutionalized the security metric in 2024 and applied it starting in 2025. However, in the offshore wind bidding conducted in the first half of 2025, not a single project was selected, leaving no way to verify whether the security metric functioned.
An official at the Ministry of Climate, Energy and Environment said, "Because Chinese-related issues arose in some past projects, we strengthened the security score," adding, "The industrial and economic impact is also related to revitalizing the domestic supply chain. Please watch for the bidding results."