Steady winds, shallow water depths and a geographically favorable location - the North Sea is predestined for the construction of offshore wind farms. Currently, wind farms with a total output of 30 gigawatts are installed, most of them close to the coast. However, in order to realize the expansion plans, the wind turbines will have to move further out to sea. But how will the electricity then reach people on land? Torben Glar Nielsen, former CTO of Energinet, and Wilfried Breuer, Managing Director of MR, came up with the idea of building artificial islands for distribution, and for this purpose together with other companies they launched the North-Sea Wind Power Hub program in 2017.
The North Sea as Europe's green power plant
300 gigawatts of electricity are to be produced by offshore wind turbines in the North Sea by 2050. The North Sea Wind Power Hub program has paved the way for this. And with its maritime solutions, MR offers the right technologies for reliable operation.
The North Sea as Europe's green power plant
300 gigawatts of electricity are to be produced by offshore wind turbines in the North Sea by 2050. The North Sea Wind Power Hub program has paved the way for this. And with its maritime solutions, MR offers the right technologies for reliable operation.
The vision: a network of artificial islands
The idea of artificial islands was born at a meeting between Torben Glar Nielsen, who was still CTO at Energinet at the time, and Wilfried Breuer, who was still working at TenneT at the time and is now Managing Director at MR. Their vision: a network of artificial islands that collect and distribute electricity from surrounding wind farms as part of a transnational power grid. To turn this vision into reality, they initiated the North Sea Wind Power Hub (NSWPH) consortium to conduct technical and economic feasibility studies in order to develop the North Sea into Europe's energy hub.
Electricity which could be redistributed by an energy island
Until now, offshore wind power has been collected on steel platforms, known as jackets, similar to those used by the oil and gas industry. Rectifier stations, which convert wind power into direct current for onward transmission to land, are located on these jackets. While the idea of these jackets is tried and tested, the possibilities for expansion are limited, and currently the jacket solution can only handle a maximum of two gigawatts of power. With the energy islands, around ten gigawatts would be possible in an initial expansion stage and later up to 30 gigawatts per island. "Up to an output of 2 gigawatts, conventional jackets are certainly the more cost-effective solution. However, our energy islands have an advantage when it comes to the planned increased output," says Nielsen.
„The energy islands could collect electricity from several offshore wind farms and distribute it to several neighboring countries via submarine cables.“
What happens on the artificial energy islands?
What happens on the artificial energy islands?
As the North Sea is only 13 meters deep in places, artificial islands could be created relatively easily. Depending on the concept, around eight energy islands would be required to realize the project in the North Sea. Plans are now becoming more concrete with a Belgian transmission system operator planning to start construction of Princess Elisabeth Island 45 kilometers off the coast of Belgium in 2024 which would be the first energy island in the world. Denmark also already has plans for an energy island off the North Sea coast of Thorsminde.
Converter stations which convert the alternating current into direct current for low-loss transmission via submarine cables, would be located on the islands. There would also be space for the storage of spare parts as well as accommodations for maintenance personnel. Other possible uses are also conceivable such as electrolysis plants which could convert surplus electricity into hydrogen directly on site. The operation of data centers would also be conceivable.
Read MoreInternational power grid on the North Sea
The energy islands could also become part of an international power grid at sea that connects several countries and offshore wind farms. Until now, the wind farms have been connected radially, like a one-way street, to the grid of the country in whose territorial waters they are located. The North Sea Wind Hub (NSWPH) consortium wants to change this and is therefore working on a new approach to connecting offshore wind farms, the so-called hub-and-spoke concept, in order to integrate green wind power more efficiently into the pan-European system.
People could be supplied with electricity from the North Sea by 2050
„Our new technical 2 GW standard will accelerate grid expansion in the North Sea and further drive the European energy transition.“
Tennet's plans at sea
The transmission system operator TenneT is a key driver of wind power expansion in the North Sea. The company currently operates offshore grid connection systems with a total capacity of around 11.5 gigawatts (GW), with the aim of reaching 40 GW by 2031. To achieve this goal, TenneT has launched the so-called 2 GW program which involves a standardized 2 GW high-voltage direct current (HVDC) transmission platform concept and a new 525 kV cable system. The aim is to accelerate grid expansion in the North Sea and further advance the European energy transition. TenneT plans to build at least 14 of these 2 GW offshore grid connection systems in the German-Dutch North Sea by 2031. Read more about this in the interview with Tim Meyerjürgens, Chief Operating Officer at TenneT.
Read MoreHydrogen on the high seas
The disadvantage of electricity is that it has to be completely dissipated every fraction of a second if you don't want to regulate it. On the energy islands, electrolysis plants could use the generation peaks for hydrogen production. Breuer explains: "The hydrogen could then be brought ashore via pipelines." This also has the advantage that the electricity infrastructure would not have to be designed for the peaks, but only for the continuous load and therefore around 30 percent smaller.
The North Sea Wind Power Hub program has already submitted technical and economic feasibility studies for the plans in the North Sea. Now politics and industry need to work together and turn the project into reality. If it proves to be successful, it would also be a model for other regions of the world.
„As the Reinhausen Group, we offer the technology and services to ensure that the grid works just as reliably at sea as it does on land.“
Service on the high seas
These systems play an important role in the energy transition and the expansion of renewable energies. Service and maintenance concepts for these systems are therefore crucial to ensure their reliability and longevity and to minimize operational failures. This requires the shortest possible response times (24/7) as well as maximum availability of materials and qualified service personnel for these operations. In addition, proactive monitoring and analysis (e.g. a proven TESSA® FS2D methodology) can be used to detect potential problems can be identified at an early stage before they lead to major disruptions.
For a reliable network at sea
Reinhausen already offers products, solutions and services for maritime offshore applications that are also suitable for the energy islands. These include:
The ETOS® automation solution and intelligent sensors
GRIDCON® STATCOM systems for stable voltage
Robust insulators that withstand salt and water
offshore wind: everything at a glance