The company will use Helgoland as an offshore operations base for its 80-turbine 288MW Amrumbank West offshore wind farm.
The 1,800 square metre building will provide space for offices and storage, with up to 50 staff working to support the operation of the wind farm by boat and helicopter. The inauguration of the building is scheduled for August 2014.
Dominik Schwegmann, the Amrumbank West wind farm project manager, commented: "Helgoland is very conveniently located and therefore an ideal maintenance base for our offshore wind farm – that way we don't have to have a hotel ship or a manned offshore platform next to the wind turbines.
"We are planning to be on Helgoland for the long term. The lease for the land has an initial term of 28 years. We are pleased that the island will benefit so much from this infrastructure upgrade."
The construction of Amrumbank wind farm is now underway, with completion and commissioning scheduled for spring 2015.