Our key tasks

We are primarily tasked with providing power transmission services, system services and facilitating the energy market. Our core tasks follow from our appointment as grid operator under the Dutch 'Elektriciteitswet' (E-wet) and the German 'Energiewirtschaftsgesetz' (EnWG).


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TenneT presents Hub and Spoke concept for large scale wind energy on the North Sea.

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Our grid

TenneT manages the high-voltage grid in the Netherlands and large parts of Germany. TenneT transmits electricity at 110,000 volts (110 kV) and higher. With around 23,000 kilometres of high-voltage lines, we cross borders and connect countries.

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Grid maps

Maps of our onshore and offshore high-voltage grid.

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Electricity market

The energy sector is developing rapidly. The process of European market integration began some years ago. Its purpose is to create a single European market that enables market parties to trade gas and electricity across national borders easily and efficiently.

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Transparency data

We provide transparency data on our operations on our Dutch and German transparency page and on ENTSO-E. 

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Our vision is to be one of the most transparent Transmission System Operators (TSO) in Europe and thereby creating value for society. In this Energy Insights section we present selected energy related topics and show data, information and valuable insights. 



Facts & figures related to TenneT facilitating the market can be found here.

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TenneT is a leading European electricity transmission system operator (TSO), with activities in the Netherlands and in Germany. We strive to ensure a reliable and uninterrupted supply of electricity in our high-voltage grid for some 41 million people.

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Offshore wind from "Niedersachsen"



  • 32 km long und 111 MW capacity
  • 4 km onshore cable
  • 28 km offshore cable

Grid connection point

  • substation Inhausen (220 kV)

Status of project

  • online since November 2017

About the project

Nordergründe is the third project within the twelve-mile zone of Lower Saxony for which TenneT is implementing a grid connection using three-phase current technology. This is both technically and economically the most efficient solution, as the Nordergründe wind farm is only about 30 kilometres from the coast. The 155 kilovolt connection has a total length of 32 kilometers and can transport up to 111 megawatts (MW) of clean wind power.

The four-kilometre-long land cable was laid as early as 2012. It leads to the Inhausen transformer station (north of Wilhelmshaven), which was expanded accordingly in 2013. The 28-kilometer submarine cable has also been successfully laid in the sea. Nordergründe can only go into operation, however, once the offshore transformer station of the wind farm has been built. According to current planning, this will be in autumn 2017. Until the submarine cable can be connected to the substation, the last piece of the submarine cable required for connection is stored on the seabed in the wind farm area about 15 kilometres east of the island of Wangerooge.

Cornelia Junge

Press Referent - Project Communication Offshore

0049 (0)5132 89-2357