Planning and projects
Pilot projects in the AC grid
In 2016, Germany’s legislators agreed to give greater scope for testing underground cabling in pilot projects. The Energy Grid Expansion Act (EnLAG) designated six and the German Federal Requirement Plan Act (BBPlG) five projects as such pilot projects. These pilot projects allow the country’s four transmission system operators (TSOs) to bury subsections of lines underground, under quite specific conditions, and to acquire much needed knowledge regarding the construction and operation of this technology. Basically speaking, we plan our AC projects with a partial underground cabling option along precisely the same lines as we do any overhead line: as space-saving as possible, in compliance with the principles of regional planning policy, and preferably bundled with existing infrastructure such as motorways and along existing routes. For the more we are able to make use of existing routes, the less we have to interfere with natural habitats.
Prioritisation of underground cables for DC lines
In Germany, legislators have set up the necessary legal framework to enable the use of underground DC cables in the nation’s transmission grid. With this measure, brought into effect at the start of 2016, the government has prioritised the use of underground cabling for four DC connections located across the country – two of which Amprion bears responsibility for: the ALEGrO project, which will transport electricity between Germany and Belgium, and the project named A North. The purpose of this second DC link is to transmit wind power from northern Lower Saxony to the Rhineland and from there to Baden-Württemberg by means of an overhead line.
According to the Amendment to the Energy Grid Expansion Act, overhead DC lines are in future only to be used whenever
- existing or already approved transmission routes can be used without any need for additional notable impact on the environment,
- the topography or environmental protection necessitate it, or
- a responsible administrative body, such as an administrative district or a local council, expressly demands overhead lines.
Furthermore, the lawmakers have provided us with a methodology for planning underground DC cabling. The key principle of this methodology: the DC cable is to run in as straight a line as possible between the legally stipulated starting and end points. This is why we are, as far as possible, planning underground DC cable routes as direct links. We only deviate from the ideal of a straight line if we need to bypass a nature reserve or a housing settlement, for instance.
|DC project (red)||AC project (purple)|
|BBPlG Project No. 1: A-Nord||EnLAG Project No. 5: WESEL–MEPPEN|
|BBPlG Project No. 30: ALEGRO||EnLAG Project No. 16: GÜTERSLOH–LOWER SAXONY STATE BORDER|
|BBPlG Project No. 6: CLOPPENBURG–MERZEN|
Step by step in constant dialogue
Germany’s Energy Grid Expansion Act (EnLAG) and Federal Requirement Plan Act (BBPlG) have set out five projects with complete or partial underground cabling, which fall within the competence of Amprion. Like all grid expansion projects, these five projects must pass through a statutory approval process.
As part of the planning procedure for all of our projects, we deliberately inform the local population, public agencies and public interest groups of our intentions from a very early stage. This naturally applies to underground cable projects, too. By doing so, we make our planning process transparent to the public at large. It also allows us to incorporate additional information, ideas and suggestions into our deliberations. On this basis, we want to develop solutions that best meet the needs of the people and the environment, are economically viable, and at the same time ensure that the new power link operates safely and reliably for a very long time.
During the course of the planning work, we weigh up a multitude of considerations based on our experiences and the discussions held with the local stakeholders, ranging from the method of construction, through the cable route, to the location of the cable transfer stations. The final decision on the actual design and configuration of the underground cable link is made by the authority responsible for the zoning approval procedure.