BBPlG Project No. 30 | Oberzier – German-Belgian border

Inbetriebnahme von ALEGrO am 9.11.2020 in Aachen

Commissioning of ALEGrO on 9.11.2020 in Aachen

Amprion and the Belgian transmission system operator Elia commissioned the first direct electricity connection between Germany and Belgium in November 2020. The interconnector is around 90 kilometres long and is called the Aachen Liege Electricity Grid Overlay (ALEGrO). The transport capacity of ALEGrO is around 1,000 megawatts (MW). The line uses extra-high voltage direct current (HVDC) transmission technology and was built as an underground cable.

Since 18 November 2020, the connection is available for the European electricity market (day-ahead). Intraday capacities went to the market 8 December 2020. The allocation of long-term capacities started at the beginning of 2021.

A unique and ambitious project like ALEGrO, the first direct electricity link between Germany and Belgium, can only be managed as a team. Four employees from Elia and Amprion talk about their close cooperation.


For European electricity trading to grow, the grid must grow with it. With ALEGrO, the first direct electricity connection between Germany and Belgium was created, providing urgently needed grid capacities for cross-border electricity flows. At the same time, ALEGrO strengthens the security of supply in the Aachen-Cologne region.

This project is part of the Trans-European Networks for Energy (TEN-E). The European Commission supported the project with funds from the TEN-E programme. The project was also included in the  European Union’s list of “PCI projects” – as a “project of common interest” urgently in need of implementation. Germany’s legislators recognised this need and added the project to the Federal Requirements Plan Act (BBPlG) as Project No. 30.

A description of the picture follows:
The information graphic in landscape format with white background shows two stylized converters in the middle of the picture. Between them, a thin dotted line represents the border between Belgium and Germany. Below the two converters runs a blue connecting line. Below it is: DC cable (DC). On both sides dotted lines lead from the converters to two stylized masts on the right and left side of the picture. Below each of the masts you will find: "AC grid (AC)". At the dotted lines is written: "Connection to the AC mains (AC)". Above the converters you will find: AC / DC conversion.
End of the picture description.

This is how ALEGrO works: the direct current (DC) underground cable is connected to the alternating current (AC) grids in Germany and Belgium via two converters.

Technology and route

The HVDC link requires a converter station at each end of the line to convert the alternating current to direct current and vice versa. The link has been build as an underground cable route between the existing 380-kilovolt stations located in Oberzier in Germany (Amprion) and Lixhe in Belgium (Elia). It has a total length of some 90 kilometres. The German section accounts for around 40 kilometres.

Route of ALEGrO, the German-Belgian power bridge between Oberzier and Lixhe.

Route of ALEGrO

Joëlle Bouillon
Joëlle Bouillon
Head of Project Communications DC