Kriegers Flak ? the world?s first offshore electricity grid

The prefeasibility study presents and discusses four technical concepts for connecting offshore wind power plants at Kriegers Flak in the Baltic Sea. One concept is a classical solution where the offshore power plants are connected nationally. This concept is com-pared to three combined solutions where the grid connection of the offshore wind power plants would also function as an interconnector between Germany, Sweden and Denmark.

This combination is called combined solution. A combined solution at Kriegers Flak would: Bring renewable energy to the European consumers, strengthen the energy markets and increase the security of supply by providing transmission capacity.

The three combined concepts illustrate how it could be technically possible to design a combined grid solution at Kriegers Flak. It is also stated that e.g. a separate grid solution together with direct interconnectors could represent an alternative to a combined solution at Kriegers Flak.

Energinet.dk has joined forces with Vattenfall Europe Transmission and Svenska Kraftnät in investigating the feasibility of constructing an offshore electricity transmission grid simultaneously linking together the electricity grids of three countries and connecting three countries’ offshore wind turbines at Kriegers Flak with the electricity grids on land.

The Danish part of Kriegers Flak – a relatively shallow area in the Baltic – has been singled out as one of several possible sites for offshore wind farms in Danish waters (four 200 MW wind farms).

What is special about Kriegers Flak is that Sweden and Germany have also got their sights set on the area as a suitable place for building offshore wind farms, and it is estimated that up to 1800 MW of wind power can be installed at Kriegers Flak.

As such, Kriegers Flak could potentially become the world’s first international offshore electricity grid with cables for exchanging electricity between Denmark, Sweden and Germany.

The project is in line with the three countries’ ministerial declarations issued in Berlin in December 2007, and it has the potential to become a pilot project for European cooperation where the planning and introduction of wind power to the grid is concerned. Collaboration has therefore been initiated with the European Commission’s working group (‘Working group for offshore/onshore grid development’) on wind power and grid expansion with focus on the North Sea and the Baltic. The group is headed by Georg Wilhelm Adamowitsch, who is the European coordinator for the connection of offshore wind farms in Northern Europe.

In cooperation with the TSOs in Sweden and Germany (Svenska Kraftnät og Vattenfall Europe Transmission) Energinet.dk has conducted a preliminary investigation of the possibilities of Kriegers Flak. Seen from a technical, financial, market and security of supply perspective, the three enterprises have looked into the possibility of entering into a joint, international project allowing the exchange of energy (electricity trade) between the three countries and the grid connection of the Danish, Swedish and Germany offshore wind farms.

www.energinet.dk/NR/rdonlyres/648CA739-6890-4E03-B18A-F21BB6A3FC5F/0/KriegersFlakPrefeasibilityReport.pdf