Norddeutsche Seekabelwerke GmbH (NSW) will be laying for E.ON Hanse AG Germany's longest submarine cable, measuring almost 53 kilometres. For supplying electricity to the island of Heligoland. Up to now, the island’s power supply has come from ageing diesel generators, which can no longer be relied upon for long-term trouble-free operation. But this year a new chapter in terms of energy provision is beginning for the high-seas island: from St. Peter Ording, Heligoland will be connected to the mainland by a submarine power cable. The project's total volume comes to around 20 million euros. Besides producing and laying the cable, NWS will also be providing the requisite accessories. The 30-kV medium-voltage cable will be manufactured in one piece, so that no maintenance-intensive joints will be required under water.
The cable is scheduled to be laid early this year – using the NOSTAG 10 barge equipped by NSW. This barge, a joint venture of companies from northern Germany, is specially designed for laying submarine power cables for offshore wind farms and island links. With a length of more than 90 metres and a width of over 27 metres, plus a very substantial carrying capacity, it is ideal for the waters of the North and Baltic Seas, which will also be the principal areas of deployment.
"For us, this order is the gateway to island link business," explains Rudolf Stahl, Managing Director of NSW. "Following the order we received last summer for the infield cabling of the Rödsand 2 offshore wind farm in Denmark, this is already the second project we've been entrusted with by a company in the E.ON Group." In the offshore category, two further orders have meanwhile been won in the North Sea: NSW is equipping both the BARD Offshore 1 and the alpha ventus wind farms with submarine power cables. In the case of alpha ventus, moreover, NSW will not only be producing the cables, but also laying them at a depth of 30 metres.
The cable for Heligoland is being manufactured in the new submarine power cable production facility, which will be starting operation in mid-February. NSW has invested more than 40 million euros in building it. Measuring over 7,000 square metres, the hall accommodates lines for stranding and armouring that rank among the most sophisticated and largest of their type worldwide. On the free area, revolving cable storage devices are provided at the ends of the production lines for intermediate storage of the cables. The cables produced on the new lines will be loaded through the firm’s own pier facility, as is NSW's standard practice.