Structures such as wind farms at open sea, situated beyond coastal waters (nearshore), are referred to as offshore.

Offshore grid connection system

Offshore grid connection systems encompass all capital goods from the interface between the offshore wind farm operators up to the onshore grid connection points, including the secondary technical and structural facilities required for the construction and operation of the connection lines. This includes the associated capital goods at the respective onshore grid connection point, such as converters, compensation coils, transformers, substations, connecting lines, operating equipment for voltage stability and operating equipment for compensation of harmonic distortion as well as other capital goods, in so far as they are required for the construction or operation of the offshore connection line.

Offshore Network Development Plan (O-NDP)

Up to the year 2017, the transmission system operators (TSOs) created a joint Offshore Network Development Plan for Germany´s exclusive economic zone and the coastal waters up to and including the onshore grid connection points. Since 1 January 2018, the transmission system operators no longer create an Offshore Network Development plan. This has now been replaced by the stipulations of the Site Development Plan (SDP).


Offshore wind farm

The term offshore wind farm is used to describe wind farms that have their foundations in the sea floor.


Structures such as wind turbines that are built on land are referred to as onshore.

Operating reserve

The operating reserve is the generating capacity, which should be available to compensate for deviations in the balance of activities between the expected and actual conditions or which is held available for specific, predictable situations.

Operational management

As a system service, operational management covers all tasks of the network operators in the coordinated use of power plants (e.g. for frequency stability) and network management as well as those of the national and international interconnected operation using central and independently-controlled centres. Additionally, this also includes all measures regarding establishment and maintenance of the necessary requirements for the calculation and billing of all services performed.