Following the developments within the North Seas Energy Forum, TenneT, the operator of the Dutch offshore grid, and The Crown Estate, the GB real estate business and seabed manager, joined forces to explore possible opportunities for further cost reduction in offshore wind through alternative grid connection infrastructure solutions. This led to the jointly commissioned study assessing the potential benefits of combining cross-border electricity interconnection with electrical infrastructure for offshore wind farms; a so-called ‘WindConnector’.
Alongside the progression of increased offshore grid integration in individual jurisdictions, this multi-use approach could both significantly reduce the overall infrastructure required and also improve the utilisation of the assets when compared with a conventional interconnector and radially connected wind farms. The study identifies potential capital savings of up to €1.8bn and increased asset utilisation from 45-50 percent up to 80 percent. The modelling undertaken by Pöyry suggests the value of market-to-market flows enabled more than offsets the investment required to install the additional infrastructure required to link the markets.
Current regulatory frameworks however present restrictions on multi-use of offshore transmission assets. In order to realise the maximum potential benefits, amendments to the regulatory frameworks would be needed. The option of allowing offshore wind transmission assets to participate in market-to-market activity through national arrangements could provide an opportunity for incremental advancement of the WindConnector concept, without the need for pan-European reforms required for full hub concepts.
The study results suggest there is a sound basis for more detailed analysis and assessment, coupled the wider interaction that will be necessary to advance this concept including with the offshore wind sector, government departments and regulators.
In support of this study, TenneT CEO Mel Kroon said: “The study clearly shows that combining infrastructure for offshore wind energy with an interconnector greatly increases the utilization rate, and with that reduce the cost of energy for consumers. We can now also examine in concrete terms to what extent a WindConnector system could also be used for future developments of offshore wind energy between the Netherlands and Great Britain."
What is a WindConnector?
A WindConnector is a hybrid form of interconnector that, like a conventional interconnector, allows for cross-border flows of energy. However, unlike a conventional interconnector, the cross-border flow functionality is provided in combination with infrastructure that also provides for connection of offshore windfarms to onshore systems.
Base situation: an interconnection cable connecting electricity markets, offshore wind farms are connected separately to the onshore grids.
Example of a situation using a WindConnector system, including an island hub.
One example of a WindConnector system would see multiple offshore wind farms connected to a central hub, which may be situated on an (artificial) island. The island hub accommodates converters that convert the alternating current produced by wind farms into direct current. Via the WindConnector, the power is then transmitted from the hub to the Netherlands or Great Britain. There, the direct current is converted back to alternating current for transmission and use in the onshore grid.
When no transmission capacity is needed for wind power, this WindConnector system will function as a ‘normal’ interconnector for trade in electricity between the Dutch and GB markets.
