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 24,500 kilometres of high-voltage lines, we cross borders and connect countries.

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Offshore Outlook 2050

Already by 2030, the originally planned capacity of 15 gigawatts of offshore wind energy will increase to 20 GW.

To Offshore Outlook 2050
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. 

To transparency pages

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 42 million people.

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We are TenneT

Meet us


Germany's longest DC grid connection



  • 205 km long and 864 MW capacity
  • 45 km onshore cable
  • 160 km offshore cable

Grid connection point

  • converter station Büttel

Status of project

  • in operation since April 2015

About the project

In April 2015, TenneT commissioned SylWin1, currently the longest offshore grid connection in the world. SylWin1 connects the DanTysk, Butendiek and Sandbank wind farms 70 kilometres off the coast of Sylt to the mainland. With SylWin1 with an output of 864 megawatts (MW), the wind farms can feed large quantities of wind power into the German power grid via a high-voltage direct current connection (HVDC). To transport the energy generated by a total of 232 wind turbines to the onshore converter station in Büttel, a distance of 205 kilometers must be bridged: 160 kilometers of submarine cable and 45 kilometers of land cable. The submarine cable route in the coastal sea and the land cable run parallel to the route for the HelWin1 project, thus reducing the impact on nature and the environment. SylWin1 is one of the large-scale offshore grid connections and can supply more than one million households with clean wind energy.

Tim Dampmann

Spokesperson - Projekt Offshore Communication