1. Current Status and Issues of Korea’s Submarine Cables
The enactment of the Special Act on the Promotion of Offshore Wind Power and Fostering the Industry and the Special Act on the Expansion of the National Power Grid in 2025 has heightened the n...
1. Current Status and Issues of Korea’s Submarine Cables
The enactment of the Special Act on the Promotion of Offshore Wind Power and Fostering the Industry and the Special Act on the Expansion of the National Power Grid in 2025 has heightened the need for offshore wind power and submarine cables in Korea. However, due to environmental concerns and conflicts among stakeholders, submarine cables (including joint access facilities and landing points) have not yet fully constructed in line with the offshore wind power development schedule. This has increased the possibility that offshore wind power operators may face operational constraints in power generation. Therefore, this study investigates domestic issues and the current management system related to submarine cables. It also conducts a comparative analysis of submarine cable management systems in major overseas countries. The goal is to propose management strategies for various problems arising among stakeholders during the planning, installation, and operation of submarine cables for offshore wind power.
2. Comparison of Domestic and International Submarine Cable Systems
A comparative analysis of domestic and international submarine cable systems revealed that the involvement of relevant power grid agencies at each stage differs, based on Korea’s Special Act on Offshore Wind Power and Fostering the Industry:
The table shows that in Korea, transmission network operators do not participate directly from the initial planning stages of the subsea grid. In Germany, site development plans are linked with grid development plans, with deep involvement beginning at the preliminary zone selection stage. In the UK, the government transmission system operator (ESO) and transmission operators (TO) participate throughout the entire High-Level Network Design (HND) phase. Japan has also recently restructured its system toward a centralized offshore wind development framework, requiring grid operators to conduct preliminary reviews from the outset. However, under Korea’s Special Act on Offshore Wind Power, transmission grid operators are absent during both the preliminary zone and implementation plan stages. While the Ministry of Trade, Industry and Energy participates in the site information network phase, it lacks access to the more substantive information possessed by transmission system operators. Furthermore, the basic design phase does not incorporate the power system interconnection plan proposed by transmission system companies. This confirms that minimizing generation and transmission constraints can be only achieved when the offshore wind subsea grid plan is meticulously developed in close collaboration with transmission system operators. Notably, Germany provides standard technologies to facilitate cooperation between offshore wind developers and transmission system operators. It also establishes commissioning schedules through time-based planning, implements periodic communication systems, and enforces penalty clauses for developers who delay projects. Similarly, Korea needs to enhance the spatial and temporal alignment of offshore wind and subsea grid development.
Regarding environmental impact assessments, Germany’s Federal Maritime and Hydrographic Agency (BMVBA) drafted site development plans and actively incorporated the Strategic Environmental Impact Assessment (SEIA) report. It also showed a tendency to streamline environmental impact assessments for accelerated and infrastructure zones. The UK also prioritized sharing overall environmental assessment results through the High-Level Network Design (HND) while allowing autonomy in planning the Detailed Network Design (DND). Japan also had the government directly conduct initial environmental reviews and publicly release the results. After site selection, the government and companies collaborated on monitoring. In contrast, while Korea requires environmental reviews at each stage, the only concrete evaluation reports produced were those submitted by the companies themselves. Furthermore, it is evident that details regarding which aspects are strengthened and which are streamlined are relatively insufficient. Specifically, it is crucial to strengthen government-led environmental assessments during the stage prior to preliminary site selection, when determining the locations for offshore wind turbines and submarine cables. Additionally, monitoring should not be entrusted solely to companies; systems must also be established to support or collaborate with companies to ensure effective implementation.
Regarding resident participation, Germany, the UK, and Japan all implemented processes for gathering stakeholder and resident opinions that were closely linked to environmental reviews. Furthermore, in Germany and the UK, systems for gathering stakeholder and resident opinions existed separately throughout all stages. In Germany and the UK, stakeholders comprised relevant central government agencies, local governments, and experts who proposed alternatives. These proposals were evaluated through a public opinion gathering system, after which the competent ministry prepared a final (draft) proposal. This proposal was then subjected to further public consultation to refine details. In contrast, in Japan and South Korea, relevant consultative bodies were established only after preliminary zones were designated. These bodies convene meetings involving government representatives, experts, and resident representatives. In Japan, fishermen are included as local representatives alongside central and local government officials and experts. South Korea extends representation to residents living along transmission lines. In Japan, the scope of fishermen’s representation is limited to representatives of local fishermen’s associations listed in relevant documents. South Korea, however, lacks a legal basis for fishermen representatives, and the scope of residents along transmission lines is also ambiguous. In such cases, ensuring proper representation of fishermen and residents along transmission line may be difficult. Therefore, it would be desirable to form a committee led by central and local governments and experts, select alternatives proposed by this committee through a public deliberation process, refine them, and then involve more fishermen and local residents.
Comparing domestic and international submarine cable systems reveals that transmission network operators must participate in the pre-site planning stage under the Special Act on the Promotion of Offshore Wind Power and Fostering the Industry. This will enable cooperation and coordination among the government, transmission network operators, and offshore wind power operators, reducing constraints on power generation and transmission. From the initial creation of the site information network map, transmission network operators should provide detailed capacity information and potential connection points. During the preliminary zone stage, the location of the substation?the starting point for the joint connection facility?should be jointly discussed. At the basic design stage, transmission network operators should lead the development of alternative connection point plans. Following community discussions, transmission capacity and completion timelines should be clarified during the development zone stage. Finally, during the implementation planning phase, coordination between transmission network operators and offshore wind power developers should be ensured, with commissioning dates aligned through a penalty system. Mechanisms may also be needed during this process to reduce the burden on the transmission network operator. Notably, Germany requires special levies on participants in offshore wind power facility tenders to support such coordination.
Regarding governance, we could consider separating the roles of a committee that develops alternatives based on analyses by the central government, local governments, and relevant experts in the early stages, as seen in Germany and the UK, from a public deliberation function that selects and refines proposals based on those alternatives. This approach allows the committee to develop more sophisticated and timely proposals while enabling broader participation from the public and stakeholders. However, while Japan also operates public-private councils, participants are clearly defined as central government, local governments, experts, and regional representatives (fishermen’s associations listed in official documents). This clarity is lacking in Korea. In Germany, the role of local governments in transmission grid construction is defined as ensuring consistency with local urban planning. The UK is also considering a model in which local residents take the lead in establishing energy spatial plans. Therefore, the role of local governments could include reviewing consistency with urban planning and, together with the central government, facilitating public deliberation to propose the direction of subsea grids, anchor points, and onshore transmission lines through the participation of fishermen and residents (including residents near transmission lines). Furthermore, during the implementation planning stage, a system will be necessary in which, under government leadership, both project operators and residents participate together to conduct environmental monitoring and carry out locally tailored planning and management. Accordingly, we propose incorporating similar provisions into the Enforcement Decree of the Special Act on the Promotion of Offshore Wind Power and Fostering the Industry.
4. Future Research Directions
Based on the findings of this study, the most urgent future research and policy priorities are identified as follows. First, to ensure the efficient integration of offshore wind power, submarine cables, landfall points, onshore cables, and connections to end-users as proposed in this study, the establishment of an energy oversight agency is necessary. This authority should mediate conflicts among various stakeholders and enhance spatial and temporal alignment to foster synergies across energy policies. Second, since low public acceptance of offshore wind and submarine cables results from insufficient integration with local spatial plans (urban and environmental planning), strengthening regional energy spatial planning is necessary to address this deficiency. Third, subsea cable planning requires greater refinement. The EU, Germany, and the UK are deploying subsea cables in an economically and environmentally efficient manner, often implementing radial interconnection networks linking offshore wind farms to enhance grid stability. As South Korea discusses its West Coast Energy Highway, concrete planning and related research are needed to determine its design and operational framework. Fourth, while this study proposed submarine cables as the sole method for transporting offshore wind energy, the EU and Germany are already utilizing hydrogen plants near offshore wind farms as alternative energy carriers. Therefore, research is needed on plans that integrate offshore wind, submarine cables, and hydrogen plants.