Onshore cables

The onshore connection infrastructure corridor, with a total length of about 14 km, will run through the municipalities of Ustka and Slupsk in the Slupsk district of the Pomeranian Voivodeship. The section between the landfall and the onshore substation is planned to use two 220-245 kV cable lines, and the section between the onshore substation and the point of connection with the National Power System is planned to use one 400 kV cable line. Prior to construction, site surveys and environmental work are carried out to plan the installation and minimize the impact on the surrounding area.

During installation, a cable corridor is used, which includes a cable trench, spool storage and an access road. There are a number of local services used before and during cable installation. These include tire cleaning of trucks leaving the construction site, road cleaning, traffic management, signage and temporary bridges over rivers and ditches. At least one construction site will be established along the cable route. The site will provide equipment storage, vehicle parking and welfare facilities for workers. Typically, it is 100 meters by 100 meters in size.

HV and EHV Land Export Cables

Tele-Fonika Kable S.A. (TFKable) is supplying high-voltage (220 kV HV) and extra-high-voltage (400 kV EHV) onshore export cables for the transmission of energy from Bałtyk 2 and Bałtyk 3 offshore wind farms. Engineered to meet the rigorous demands of offshore environments, these cables play a critical role in ensuring a secure and long-lasting connection between offshore infrastructure and the onshore grid. Onshore export cables are a key element of the wind farm’s transmission architecture. Their robust construction, environmental ageing resistance, and consistent electrical performance mitigate the risk of failure and downtime, ensuring the dependable delivery of renewable energy to the national transmission system.

Manufacturing Process and Technical Oversight

TFKable’s production facility in Bydgoszcz, located approximately 250 km from the project site, is responsible for the end-to-end manufacturing and testing of the onshore export cables. The factory operates in full alignment with offshore wind sector standards. Its proximity to the installation site and established local technical base ensure timely service support, streamlining the entire logistics and installation process. Manufacturing involves advanced production technologies, automation of critical process stages, and a comprehensive multi-tier quality control system. Each production batch is tested in-house at TFKable’s R&D laboratories, with final verification carried out at a PCA-accredited high-voltage testing laboratory. Continuous monitoring of technical and mechanical parameters ensures full compliance with the demanding standards of the renewable energy industry.

Standards Compliance and Product Assurance

HV and EHV cables supplied for Bałtyk 2 and Bałtyk 3 offshore wind projects fully comply with international standards, including IEC and CIGRE specifications, alongside the bespoke requirements of the offshore sector. Testing includes assessments of environmental durability, mechanical resilience, and long-term electrical stability. As the only manufacturer in Poland producing both HV and subsea cable solutions, TFKable guarantees full compliance with the stringent performance and reliability standards required for large-scale offshore wind developments.

Onshore export cables are an essential part of the transmission system of offshore wind farms, enabling the transportation of generated energy from the "landfall" point to major distribution points in the national power grid. Installation of these cables requires careful planning and coordination to ensure their efficiency and safety. Before installation begins, field surveys are conducted to determine the most optimal route for the cables. This is followed by field works, during which the cables are laid and buried at the appropriate depth, protecting them from mechanical damage and weathering. Specialized equipment and technology are used to lay the cables, ensuring precise laying and minimizing disruption to the local community and environment. During installation, technical parameters of the cables, such as resistance or capacitance, are also monitored to ensure proper operation. Once the installation is complete, functional tests are conducted to confirm that the connections are correct and the system is ready to transmit energy. The entire process of installing export cables onshore is crucial to ensuring the reliability and performance of offshore wind farms, representing an important step in their supply chain.