Advancing Meshed Offshore Transmission Grids

A meshed grid offers benefits for transmission of power from offshore wind farms.
Published: Tue 29 Mar 2016

Offshore wind offers significant potential to expand renewable generation, and for example in Europe, which has led offshore developments, the technology is seen as key to meeting the regions’ long-term energy security requirements. [Engerati-Offshore Windfarms Set To Reach New Levels and Europe’s Offshore Wind Market Levels Off]

However, in order to unlock the full potential of these offshore resources, particularly in the North Sea, network infrastructure is urgently required linking the offshore windfarms with onshore grids.

The first commercial HVDC projects have implemented point-to-point connections, point-to-point and multi-terminal deep offshore grids. In order to provide additional flexibility, efficiency, security and market access to offshore wind resources, meshed offshore grids are required. However, their deployment is currently hindered by a number of barriers. These include the high cost of converter technology, lack of experience with protection systems and fault clearance components and absence of interoperability and multi-vendor compatibility of equipment. In addition, there are limitations to regulations for cross border offshore infrastructures and financing issues.

PROMOTioN to boost HVDC offshore grids

In order to address these barriers, the ‘PROgress on Meshed HVDC Offshore Transmission Networks’ (PROMOTioN) project has been initiated, with support from the EU Horizon 2020 research programme.

With a total cost of €51.7 million, of which the EU contribution is €39.3 million, the project is currently the biggest energy project in the programme.

The goal of the project is to develop and demonstrate three key technologies: diode rectifier offshore converters, multi-vendor HVDC grid protection systems, and the full power testing of HVDC circuit breakers. Further, a regulatory and financial framework will be developed for the coordinated planning, construction and operation of integrated offshore infrastructures, including an offshore grid deployment plan (roadmap) for the future offshore grid system in Europe.  

“There is great potential in the Northern Seas to deliver significant quantities of clean energy, helping us both to decarbonise our economy and to increase the security of our energy supply,” commented Marie Donelly, Director Renewables, Research and Innovation, Energy Efficiency – DG ENER. “We think that an offshore grid in the North Sea could become a flagship project for regional cooperation as foreseen by the Energy Union.”

The Northern Seas Offshore Grid was named as one of the Projects of Common Interest in the second list which was released late last year. [Engerati-Energy Projects of Common Interest]

PROMOTioN project consortium

The project is being undertaken by a consortium of 34 TSOs, offshore wind developers and suppliers, academic institutions and other organizations under the coordination of DNV GL.

“Combining new HVDC technologies within present systems is instrumental in bringing large scale renewables into the grid and to ensure a future-proof grid which is affordable, reliable and sustainable,” commented Elisabeth Harstad, CEO DNV GL – Energy. “I am confident DNV GL can guide the consortium in realizing this important project.”

The project was formally launched in January and runs through December 2019.