Electric power supply of the isles - A new underwater cable connects Holland and Langenes
A new power cable has been laid between the Hallig islands of Langeneß and Oland. The previous cable from the 1950s had to be replaced due to aging, as SH Netz announced. "Laying a power cable is rare and a very complex undertaking," said Project Leader Marius Bruhn. "All work depends on the weather and tides."
The new 20,000-Volt power cable is approximately 4.5 kilometers long and connects the Hallig islands of Oland and Langeneß. It will be connected to a local network station on both islands, which transforms the voltage to 400 volts low tension, with which the two island grids are operated. Via another power cable between Langeneß and Dagebüll, the two islands are thus connected to the mainland power grid.
Lower ground load than for Watt walkers
The power cable was transported from the factory in England to Dagebüll by sea. There, it was loaded onto the special ship "Catjan," which then let itself down in the Watt next to the amphibious vehicle "Nessie."
The 18-meter-long and 91-tonne device is equipped with a vibration plow blade. With this, the new power cable was dug into the Watt of Langeneß about 1.5 meters deep. "The ground load per square centimeter from Nessie is lower than that of a person walking through the Watt," Bruhn said. With this cable-laying method, the environmental impact in the UNESCO World Natural Heritage National Park Wadden Sea will be kept as small as possible.
Another power cable to Föhr will still be laid
Strict environmental and nature conservation regulations apply. Work can only be done from mid-April to the end of September due to breeding seasons. "Two boreholes for protective pipes from the Wadden Sea onto the islands were already drilled last summer," Bruhn said. The power cables are now being inserted into these.
In the coming weeks, Schleswig-Holstein Netz will still lay two new power cables between the mainland and the island of Föhr. A total of 23 million Euros will be invested in the laying of the three new power cables.
- The decision to replace the old power cable from the 1950s in Schleswig-Holstein was made due to its aging condition, as announced by SH Netz.
- The construction of the new power supply for the Hallig islands of Langeneß and Oland will not only improve their power supply but will also contribute to reducing the environmental impact in the Wadden Sea, as explained by Marius Bruhn.
- The new power cable laid between Langeneß and Oland is a significant project, not only for the Hallig islands but also for the mainland, as SH Netz will invest a total of 23 million Euros in laying three new power cables, including one to the island of Föhr.
- The process of laying the new power cable in Schleswig-Holstein involves complex activities, such as transporting the cable from England, lowering it into the Watt via the special ship "Catjan" and "Nessie", and digging it into the ground using a vibration plow blade, ensuring minimal impact on the UNESCO World Natural Heritage National Park Wadden Sea.
