Substation: the heart of the wind farm

DanTysk Offshore Substation (Source: Strukton)

A central element of the DanTysk wind farm is the 155/33-kilovolt offshore substation. It forms the gateway for the onward transport of energy to the mainland via submarine cables. This is where the electricity generated by the whole wind farm is converted from 33 kilovolts into 155 kilovolts before it is transferred to a converter station. Here the energy is converted from AC to DC voltage to ensure the electricity is transferred with as little loss as possible.

The latest technology in German high seas

The joint venture Strukton/Hollandia began construction work on the wind farm's substation in the Netherlands in spring 2012. In summer 2013 the unit will be transported by ship to its permanent site, 70 kilometres off the island of Sylt, where it will be anchored to the sea floor. The water at this site reaches a depth of 26 metres.

Sturdy construction to protect against the elements

The substation will be built based on the so-called jacket/topside design. The jacket is the foundation and forms a steel construction which stands roughly 45 metres tall. This structure will be installed on the bed of the North Sea, its foundation pile supporting the topside where all the technological equipment is housed. This closed design means that the substation, which reaches an overall height of 75 metres, is well protected against the adverse weather conditions on the North Sea. The structure will contain a total of three decks and, due to its isolated location, a helicopter landing pad and a petrol refill station.

Dual assurance

The offshore substation is characterised by its dual set of transformers. Both of the main transformers are so large in size that one unit alone could transfer the entire energy generated by the wind farm should the other fail. This means that even if one component is faulty, the substation will still ensure that the energy generated by the farm can be transferred onto shore. The substation's topside contains control rooms and emergency generators, as well as a crane and a helicopter landing pad on the deck.