Nexans has successfully completed a new 75 km subsea power link between Pemba Island, the second largest island in the Zanzibar archipelago, and the National Grid on mainland Tanzania.
The 25 MVA link, opened officially on 3 June by President Amani Abeid Karume of Tanzania, has enabled Pemba's population of 300,000 people to end years of dependence on unreliable, erratic diesel generation subject to frequent power cuts. The availability of dependable electrical power is expected to assist the economic and social development of Pemba Island by opening up new economic opportunities and encouraging tourism.
The Pemba cable project has been financed through a grant of €45m from the Norwegian state, while the Zanzibar government has contributed €8m and the Union government €4m. Norplan has managed the project on behalf of the Norwegian Ministry of Foreign Affairs and ZECO, the Zanzibar Electricity Corporation.
The 36 kV PEX (XLPE) insulated cable was designed and manufactured at Nexans' specialized subsea cable factory in Halden, Norway and incorporates optical fibre elements supplied by the Rognan factory, also in Norway. The cable, weighing over 4,300 tonnes, was loaded onto Nexans' own installation vessel, the C/S Nexans Skagerrak, and shipped to the Pemba Channel.
The cable route runs from Tanga on the Tanzanian side to Pemba Island and required installation under challenging conditions. There are shallows on each side, and the cable needed to be floated out for more than four kilometres before the sea bottom falls away steeply, after which the cable was guided down to a depth of 850 metres.
The fast-track project made rapid progress from the initial signing of the contract in 2008 and the new cable started supplying electricity to Pemba from the mainland in early 2010.
"The Pemba Island project is a great example of our proven capability to implement subsea cable links in even the most demanding and difficult condition and within short timescales", says Krister Granlie, managing director of Nexans' Umbilicals & Submarine High Voltage Business Group. "It is also especially pleasing to see the successful conclusion of a project that will make a real difference to the daily lives of the local population."
