National Grid ESO has issued the Phase 1 Final Report of its offshore co-ordination project, assessing the most beneficial approaches to offshore networks to deliver better outcomes for consumers and coastal communities
One of the challenges to delivering the UK’s ambition of 40 GW of offshore wind by 2030 is ensuring the offshore and onshore transmission network enables this growth in a way that is efficient for consumers and takes account of the impacts on coastal communities and the environment.
The ESO Offshore Coordination project forms part of the Department of Business, Energy and Industrial Strategy Offshore Transmission Network Review (OTNR). The ESO project examined a more co-ordinated approach to offshore network development, including the connections required and technology availability, and assessed the costs and benefits of such an approach to inform the OTNR. It launched a consultation on 30 September 2020 to seek stakeholders’ feedback on its approach.
In response to feedback, National Grid ESO conducted a sensitivity analysis on the impact of commencing integration in 2030, compared to integration commencing in 2025, as in its original analysis. This confirms there is significant benefit in moving quickly to an integrated network and the importance of considering what flexibility there is for co-ordination between 2025 and 2030.
National Grid ESO said the key messages in its Final Phase 1 report, published on 16 December 2020, are that adopting an integrated approach for all offshore projects to be delivered from 2025 has the potential to save consumers approximately £6Bn (US$8Bn), or 18%, in capital and operating expenditure between now and 2050.
It also found there are significant environmental and social benefits with an integrated approach, as the number of new electricity infrastructure assets, including cables and onshore landing points, could be reduced by around 50%.
The report noted that delivering the integration required in this timescale would be “extremely challenging” and “potentially risky” to meeting the target of 40 GW of wind by 2030. However, the benefits reduce the later integration begins.
The report states that an integrated approach for projects to be delivered from 2030, compared to the status quo, would deliver savings to consumers of around £3Bn (or 8%) and could facilitate a 30% reduction in the new electricity assets associated with these offshore connections.
It also states there is a need to deploy innovative and flexible approaches to the connection of offshore wind in the intervening period until a new enduring, integrated, approach is in place such that, as much as possible, the benefits of an integrated approach can be captured without placing delivery of projects underway and the offshore wind target at undue risk.
The increased levels of offshore wind mean there will be an increase in onshore infrastructure in all options, including, and potentially beyond, that set out in the Network Options Assessment. However, adopting an integrated approach across onshore and offshore can minimise the overall increase.
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 high voltage direct current (HVDC) circuit breakers. A targeted innovation strategy in the UK, along with support for early commercial use, could help progress HVDC circuit breakers to commercial use and establish the UK as a world leader in offshore grids.
“There is also a need for all parties to work collaboratively and at pace to enable Great Britain to achieve its offshore wind targets and net zero ambition at least cost to consumers and with least impact on communities and the environment,” the report concludes.