The two-storey building, which will contain a warehouse, office space and workshop, is being built in the island’s south port. It will service RWE’s 295MW offshore wind project 35km to the north-east of the island.
"Offshore wind turbines cannot be serviced at any time of day or night," said RWE Innogy project engineer Peggy Kleidon.
"We need a safe operating base that is as close to our wind farm as possible since at sea every mile costs."
The Nordsee Ost project, which will use 48 6.15MW Repower turbines on jacket foundations in water depths of up to 25m, is scheduled to start generating electricity next year.