The small port of Ramsgate on the Kent coast in England is already active as a service and maintenance base for Swedish utility firm Vattenfall’s offshore farms, Kentish Flats and Thanet. The berths to take vessels that will service the London Array offshore farm, a two-phase 100MW project, will also be completed at Ramsgate in 2011, under a construction, service and maintenance contract with project owners Dong Energy, E.on and Masdar. This includes a 50-year lease for 8,000 square metres of land for the new operations and maintenance (O&M) base, and overnight berthing for six O&M vessels.
In Germany, where the offshore wind business is less advanced, initiatives are now under way to establish the opportunities for the offshore servicing and maintenance business, and to coordinate development of the ports on the North Sea and Baltic Sea coasts.
Reaction and supply
Two types of service and maintenance ports are needed, according to Martin Schmidt, manager at Windcomm Schleswig-Holstein, a wind energy network agency in the windy northern German state of Schleswig-Holstein. The first type, reaction ports, are small service ports within two hours’ journey of the offshore farm. Small boats will carry crews and components daily to the offshore farm. Such ports will generally require quay space for up to four 20-metre service boats and up to 2,000 square metres of storage, Schmidt says, although in many cases much less will suffice.
Supply ports, from which trips to the offshore farm take place once or twice a week, will be larger and able to accommodate vessels carrying components of up to 20 tonnes, or parts such as a rotor blade or blade hub. Ports like Cuxhaven or Brunsbüttel could fill this role, says Schmidt, while fishing and tourist ports, like Husum and Büsum, could act as both types of port.
"Almost any port close to an offshore wind farm can provide service and maintenance facilities," says Andreas Wagner, managing director of the German offshore wind energy foundation Stiftung Offshore. The key requirements are 24-hour accessibility, the ability to accommodate small service ships, storage space for spare parts, and the availability staff and tools, he says.
"It’s important that the port has no tidal restrictions, no locks and that local authorities are in favour of the new activity," says Oliver Heinecke, managing director of All for Offshore, a German company aiming to specialise in offshore service and maintenance. "Local parishes and authorities may fear an impact on tourism."
Ramsgate is already demonstrating how a reaction port should work. Access time is only 30 minutes to the newly completed 300MW Thanet wind farm’s 100 Vestas 3MW turbines, and to the 90MW Kentish Flats project, with 30 Vestas 3MW machines. Vattenfall also uses the nearby port of Whitstable, although it does not offer 24-hour access. "At low tide, the port dries up but we work around this," says Mandy Broughton of Vattenfall Wind UK. She says that 20 technicians work out of both ports, travelling between them as required. A jack-up vessel can be ordered from Felixstowe or Dunkirk for larger components, Broughton adds.
The new service and maintenance business did not need major upfront investment but has brought many advantages, says Ramsgate’s harbour master, Robert Brown. These include rental income from offshore operators for their onshore facilities, an employment boost for local people who provide ancillary services, and stimulation of the local economy with business visitors staying at local guest houses and hotels.
Ramsgate’s success led the German federal environment ministry to launch a round-table initiative in October, the Port Infrastructure for Offshore Wind Energy Use, to debate port activities for the government’s 2030 target of 25GW of offshore capacity. In parallel, Stiftung Offshore is working to step up links between the maritime industry and offshore wind.
Companies at the ports have been swift to react and grasp the new business. Ahlmann-Zerssen, based at the ports of Rendsburg and Brunsbüttel, and Wilhelms EF Schmid of Husum, have set up a port co-operative for the German west coast to expand service infrastructure for offshore wind farms.