Regional boundaries offshore have never been closely scrutinised before. The report -- on its way to the Lower Saxony government for approval -- says the relevant planning authority for a site depends on a wind plant's distance from the shore. Less than 12 sea miles (22 kilometres) from the coast, then the regional governments of Weser-Ems and Lüneburg are theoretically responsible for planning and licensing. This has never been put to practise however. Lower Saxony officials are waiting for an agreement on the issue between neighbouring Schleswig-Holstein and the city state of Hamburg before making a decision.
Meanwhile, sites between 12 and 200 miles offshore, where international waters begin, must be authorised by the office for shipping under the federal ministry for transport, construction and housing (BVBW).
The report includes ten provisional guidelines from BVBW to help co-ordination and ensure that shipping traffic is not disturbed. A safety zone of one sea mile (1.83 kilometres) between the turbines and marked shipping routes is called for as well as rules on visibility and radar surveillance, signage and cabling.
Aside from the shipping question, offshore wind planners have met resistance from residents of Germany's North Sea islands, a popular tourist area. "Obviously you can see the turbines from the islands, so it is important to make it clear to the islanders where the benefits lie," says Horst Schörshusen of the Lower Saxony government, one of the report's authors. Another challenge is posed by the offshore nature reserve, an area of mud flats forming a long stretch of the coastline. Because the area is protected, cabling issues are particularly difficult. A steering group hopes to reduce friction encountered with both tourism and the national park with a nine kilometre buffer zone between turbines, the national park boundaries and the island shores.