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. 

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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 42 million people.

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We are TenneT

Meet us


Grid connection for 128 offshore wind turbines off the coast of Helgoland



  • 130 km long and 575 MW capacity
  • 45 km onshore cable
  • 85 km offshore cable

Grid connection point

  • converter station Büttel

Status of project

  • in operation since February 2015

About the project

With HelWin1, TenneT has completed a 130 km long and 576 megawatt (MW) direct current grid connection near the North Sea island of Helgoland. It has been in operation since February 2015 and runs 85 kilometres from the Helwin alpha converter platform on the lake side to the landing point near Büsum. From there it runs over 45 kilometres of land cable to the converter station and the transformer station in Büttel. Along with BorWin2, HelWin1 is the first major project to be implemented by TenneT, which enabled more than one offshore wind farm to be connected to the power grid.

The heart of this network connection, the offshore converter platform HelWin alpha, plays a special role: It acts as the parent platform for HelWin beta, the sea-side platform for the HelWin2 network connection, which is directly adjacent and connected by a bridge so that HelWin alpha's crew quarters and helicopter deck can be shared.

Tim Dampmann

Spokesperson - Projekt Offshore Communication