The present invention relates to an offshore wind turbine comprising a tower, where said wind turbine at a level above sea level comprises at least one structure for storing at least one container, said container having the size and measures of a standard container, where said structure is arranged on the side of the tower. The invention further comprises a method of manufacturing such a concrete structure for an offshore wind turbine. The structure for storing one or more containers according to the invention comprises a deck, and at least one bed for supporting at least one container along said containers lower surface and/or edges, where said structure is a concrete structure. By manufacturing said structure from concrete a very robust and strong structure is achieved.