By hooking up offshore wind farms to the system, 50Hertz creates important preconditions for climate protection. The onshore and offshore extra-high voltage grid is extended wherever new capacity is needed to transport electricity generated from renewable resources. 50Hertz is highly committed to assuming this responsibility, making its technical know-how available at the service of climate protection and the future energy mix. There is also a legal obligation to develop the networks. The German transmission system operators have been obliged by law since 17 December 2006 to build grid connections of the planned German offshore wind farms by the time the latter are commissioned, and to operate them following construction. This obligation has, since 01 January 2009, been in force for offshore wind farms construction for which commences before the end of 2015.
Grid connection of wind farms in the Baltic Sea
The Energy Industry Act (EnWG) defines which transmission system operator is responsible for connecting up the offshore wind farms. For the Baltic Sea, this is 50Hertz. 50Hertz has been commissioned with this task. Connection of the offshore wind farms built in the North Sea will be the responsibility of the local transmission system operator.
Licencing wind farms
Licencing of offshore wind power generation facilities located in the Exclusive Economic Zone (EEZ) is incumbent on the Federal Maritime and Hydrographic Agency of Germany (BSH). Licences for wind generation units located within the 12-mile zone will be granted by the respective Federal states. For the Baltic Sea, these are the German states of Mecklenburg-Western Pomerania and Slesvig-Holstein.
The Exclusive Economic Zone (EEZ)
The Exclusive Economic Zone (EEZ) denotes the area stretching from the seaward edge of a state's territorial sea out to 200 nautical miles from its coast (the so-called baseline) under the international law of the sea. In the Baltic Sea, the EEZ of Germany borders on the EEZs of Denmark, Sweden and Poland. Within the scope of its jurisdiction, a coastal state may erect artificial islands, installations and structures like drilling rigs, and conduct scientific maritime research in these zones. For Germany, the provisions of the Ordinance on installations at sea (SeeAnlV) must be adhered to.
Grid operator and wind farm facilitator
50Hertz is grid operator and only responsible for connecting the wind farms in the Baltic Sea. We are no wind farm facilitator.
The outcome of the efficiency reviews we conducted with regard to the technical connection concepts is that 150 kV three-phase connections will be used in most cases.
AC or DC
Technical/commercial concepts based on three-phase electricity lend themselves especially well to connecting offshore wind farms less than 100 km away from the nearest grid connection point.
Man and nature
A licence for an offshore wind farm and its grid connection will be based on elaborate investigations into, and proof of, environmental compatibility with regard to flora and fauna and to the project’s impact on other human interests like navigation and tourism. No project will be licensed without such proof being submitted.
Grid connection onshore
On aggregate, 19 offshore wind farm operators have applied to us for a grid connection. We have classified these projects as belonging to the “Region West“ with its 380 kV connection point being in Bentwisch, and “Region East“ with Lubmin as its 380 kV connection point. Preliminary works for integration of this wind energy into the 50Hertz transmission system are ongoing at both of these connection points.