Skagerrak 4

Overview

Skagerrak 4 is a submarine cable system connecting Denmark and Norway across the Skagerrak strait. With a length of 137 kilometers, it provides a vital link between these two Scandinavian neighbors. The cable is owned and operated by Statnett, the Norwegian state-owned enterprise responsible for managing the country's high-voltage electricity transmission system. Skagerrak 4 plays a key role in facilitating cross-border energy exchange between Norway and Denmark, leveraging the geographical proximity of the two nations.

Commissioned in 2014, Skagerrak 4 has been operational for nearly a decade. Its relatively short span compared to other submarine cables in the region underscores its focused purpose: to provide a direct and efficient connection between the two landing points, Tjele in Denmark and Kristiansand in Norway. The cable is an integral part of the broader regional infrastructure that supports energy transmission and connectivity in northern Europe.

Route and Landings

The Skagerrak 4 submarine cable crosses the Skagerrak strait, a body of water that separates the Jutland Peninsula in Denmark from the southern coastline of Norway. It connects Tjele, located in central Denmark, to Kristiansand, a key port city in southern Norway. The route spans 137 kilometers, making it a relatively short but strategically significant connection in the region.

Tjele, the Danish landing point, is situated in a region known for its agricultural and industrial activities. It serves as a hub for energy infrastructure in Denmark. On the Norwegian side, Kristiansand is a major urban center and a gateway to the North Sea, with a strong maritime heritage and a growing role in renewable energy initiatives. The choice of these two landing points reflects their importance in the energy networks of their respective countries, as well as their proximity across the Skagerrak strait, which minimizes the cable's length and enhances its efficiency.

Ownership and History

Skagerrak 4 is wholly owned and operated by Statnett, the Norwegian transmission system operator. Statnett is responsible for the development and maintenance of Norway's high-voltage electricity grid, including its international interconnectors. The cable was built to strengthen the energy exchange between Norway and Denmark, leveraging Norway's hydroelectric power resources and Denmark's wind energy capacity to create a more balanced and resilient energy system for both countries.

The cable became operational in 2014, marking an important milestone in the region's energy infrastructure development. It is part of a series of interconnectors in the Skagerrak corridor, which has been a focal point for energy cooperation between Denmark and Norway. Skagerrak 4 complements earlier cables in the corridor, enhancing capacity and reliability while supporting the integration of renewable energy sources into the regional grid.

What Our Measurements Show

Our live monitoring of Skagerrak 4 has provided detailed insights into its performance. We have measured 147 distinct data corridors along the cable's length. The best round-trip time (RTT) recorded is 13 milliseconds, while the average RTT is 17 milliseconds. These figures are consistent with the cable's relatively short length and its efficient design, which minimizes latency between the two landing points.

The low latency and reliable performance of Skagerrak 4 are critical for the real-time management of electricity flows between Denmark and Norway. This capability supports the integration of renewable energy sources, such as wind and hydroelectric power, into the regional grid. The cable's performance also highlights the strategic importance of its location, as it enables fast and efficient energy exchange across the Skagerrak strait, contributing to the stability and sustainability of the northern European energy network.