50Hertz and Energinet inaugurate world-first hybrid interconnector

The combined grid solution (CGS) connects two offshore substations in the Baltic. It also connects to existing onshore connections for the windfarms. As a result, the CGS can transmit power to Denmark or Germany and can also be used for cross-border energy trading.

Speaking at the inauguration ceremony, German Federal Minister for Economic Affairs Peter Altmaier, Danish Minister for Climate, Energy and Utilities Dan Jørgensen and EU Commissioner for Energy Kadri Simson all praised the innovative project. Mr Altmaier called the CGS a “European lighthouse project” for cross-border co-operation in offshore wind.

The CGS uses the grid connections for the Baltic 1 and Baltic 2 offshore windfarms in Germany, operated by 50Hertz, and the connection for the Kriegers Flak offshore windfarm in Denmark, which is currently under construction.

Two 25-km submarine cables, each with a capacity of 200 MW, are laid between the Baltic 2 and Kriegers Flak offshore substations, bringing both grid connection systems together.

50Hertz chief executive Stefan Kapferer said, “With this project, 50Hertz and Energinet are pioneering the efficient integration of offshore windfarms into the cross-border European electricity market.

“It offers us several options to balance the frequency and voltage of our transmission grids, deal with the integration of renewable energy sources in a more flexible way and increase the stability of the system.”

Elia Group (of which 50Hertz is a part) chief executive Chris Peeters said, “Hybrid technology increases the efficiency of investment: when there is no wind, the cable can be used as an interconnector. In this way, the CGS links two energy markets and gives access to renewables at the lowest cost. This is of vital importance to energy-intensive industries."