An efficient North Sea grid would unlock the unconstrained exchange of energy between countries and bring energy from places with higher wind resources, said WindEurope CEO Giles Dickson during a June 6 panel discussion focused on the potential benefits of meshed offshore grids in Europe.
According to Dickson, a meshed offshore grid should not be the goal itself; rather, it should be treated as a means of deploying competitive wind generation across the North Sea. The discussion took place at the mid-term project conference organized by the Horizon 2020 project PROMOTioN (PROgress on Meshed HVDC Offsfhore Transmission Networks).
Several key EU projects – including PROMOTioN and Best Paths – currently demonstrate how HDVC (high voltage, direct current) technology is rapidly evolving. Advanced wind-turbine converters, along with smarter HVDC converters, will be key to supporting system operations and maintain-system security. Already, HVDC interconnectors provide a vast amount of flexibility for transmission system operators (TSOs), Dickson said, adding that HDVC technology is now gearing up for multi-vendor, multi-connection wind farms which may be connected to two different onshore grids.
The biggest challenge, Dickson said, remains with the current regulatory framework. Today, investors are not encouraged to develop wind farms and infrastructure that are ready for future meshed grids. Instead, investors compete in auctions on the lowest price, a process that ensures there will only be a single connection point to a single onshore substation. As long as this does not change, future retrofitting will be needed for a meshed grid. But this falls outside the business plans of many investors – creating a lack of incentive for meshed grids going forward, he added.
Dickson also addressed the role that TSOs can play in addressing the obstacles to meshed grids. Today, TSOs are building point-to-point (country-to-country) interconnectors to reap the benefits of wholesale price differences between markets. This allows wind farms to plug in to their interconnector, potentially reducing the income for TSOs and thus decreasing the incentive to adapt the existing infrastructure.
However, in some countries, the TSO is in charge of deploying the grid, he explained. As the TSO is regulated in these countries, it has the potential to develop an optimal solution for both the wind promoters and grid promoters. This is because the possibility of achieving ‘hybrid projects’ is much higher. Hybrid projects are projects that feed electricity to two different markets, as exemplified in Kriegers Flag, part of a 400-MW interconnector between Denmark and Germany.
Dickson outlined a number of recommendations to unlock the potential for hybrid projects, as proposed by WindEurope’s Offshore Working Group:
- Hybrid projects comprising offshore wind energy and grid interconnectors should add volumes to the existing pipeline.
- Hybrid projects should be subject to competition, including project elements.
- Pilot hybrid projects should be carefully selected in such a way that they will not jeopardize current plans and investments and should benefit from compensation schemes.
- Hybrid projects should build on the short- to medium-term development plans from governments.
- The future framework should be clarified by designing a European Offshore Grid blueprint to 2030 and beyond.
- The most economically beneficial sites should be developed first.
A meshed European offshore transmission grid connecting offshore wind farms to shore could provide significant financial, technical, and environmental benefits to the European electricity market, Dickson said. Launched in January 2016, PROMOTioN aims to explore and identify these potential benefits.