Artificial magnetic fields are unavoidable features of offshore wind farms in natural geomagnetic field environments. The movement of the wind over the blades makes them rotate and a connected shaft powers a generator to convert the energy into electricity. This electricity is transmitted by cables over long distances. Operating electric currents always produce magnetic fields, which are essentially dipolar in nature, having a north and a south magnetic pole.
The magnetic field lines of a straight current-carrying wire form concentric circles around the wire. The direction of the magnetic field is perpendicular to the wire and defined by the human right-hand rule, where the thumb of the right hand points in the direction of the conventional current and the fingers curl around the wire in the direction of the magnetic field. Direct electric currents (DC) produce static magnetic fields.