A newly-published report from the National Grid Electricity System Operator suggests that a more integrated approach to the connection of offshore wind and interconnectors in the UK would be beneficial for consumers, coastal communities and the environment
Publication of the report forms part of review into the existing offshore transmission regime to address the barriers it presents to further significant deployment of offshore wind, with a view to achieving net zero ambitions.
In the current approach to offshore transmission, developers are responsible for transmission lines brining power ashore from offshore windfarms. This approach to designing and building offshore transmission was developed when offshore wind was a nascent sector and industry expectations were as low as 10 GW by 2030. It was designed to de-risk the delivery of offshore wind by leaving the project developers in control of building the associated transmission assets to bring the energy onshore. It has contributed to the maturing of the sector, cost reductions and has helped position the UK at the forefront of global offshore wind deployment.
However, in the context of increasingly ambitious targets for offshore wind, constructing individual point-to-point connections for each offshore windfarm may not provide the most efficient approach and could become a major barrier to delivery, given the considerable environmental and local impacts, particularly from the associated onshore infrastructure required to connect to the national transmission network.
The report, ‘Offshore Co-ordination project: scope for phase 1’, said analysis suggests an integrated approach offshore could save consumers approximately £6Bn, or 18%, in capital and operating expenditure between now and 2050.
Savings are greatest – up to 30% – where high levels of offshore wind need to be connected to parts of the onshore network already nearing operational limits, or where windfarms are located far from shore.
There are also potentially significant environmental and social benefits, as the number of onshore and offshore assets, cables and onshore landing points could potentially be reduced by around 50%, albeit that some of these assets would be somewhat larger.
Most of the technology required for the integrated design is available now, or will be by 2030. However, a key component to release the full benefits of an integrated solution are HVDC circuit breakers. A targeted innovation strategy could help progress these assets to commercial use and establish the UK as a world leader in offshore grids.
“Changes to the offshore connection regime will drive more coordination,” said the report. “These include reviewing the assessment process for the location of offshore connections, investigating the packaging of connection offers with other elements such as seabed leases, and a review of where liabilities sit for offshore connections.”
The report noted that many projects due to connect ahead of 2030 will have connection agreements already in place and it will be important to work with the relevant transmission operators and developers to continue to progress on the basis of those agreements.