Offshore Wind Energy Could Fill the Gap Left in the UK's Climate Goals in the Absence of Nuclear

This blog was coauthored by Yvonne Deng and Raya Peterson.

Toshiba and Hitachi recently announced that they are suspending the development of their proposed new nuclear facilities in Cumbria and Anglesey, respectively. These announcements raise questions over the extent to which nuclear power can contribute to the UK’s energy mix over the coming decades, as well as the UK’s progress toward meeting its legally binding targets to reduce emissions. 

The UK has spearheaded emissions reductions: it was the first country in the world to implement a legally binding emissions reduction target (80% by 2050 versus 1990 levels) and has led the way in the G7, achieving 43% reduction by 2017. So far, the UK has met its first two interim targets and is on track to meet the third by 2022, with the bulk of emissions reductions coming from electricity generation (emissions from electricity generation fell by 59% between 2008 and 2017). 

However, the UK is not on course to achieve its fourth and fifth targets covering the period of 2023–2032. To do so, the Committee on Climate Change (CCC), a government advisory body, recommends that the grid average carbon content of electricity supply be less than 100 gCO2/kWh by 2030 (it is currently just below 300 gCO2/kWh). Other sectors will need to pull their weight—for example, through electrification of transport—but the power sector needs to retain momentum in its decarbonisation pathway to ensure this shift to electricity reduces emissions as fast as possible.

There are three options to rid the power sector of emissions: renewables, nuclear, and CCS. The options most likely to play in the UK power market are nuclear and renewables, given their current maturity and cost point. 

Considering the age of the existing nuclear stock and the recent shelving of projects, the contribution from nuclear power is likely to decrease in coming decades unless there is tangible government support. Given relative economics and financial risk profiles of nuclear power versus renewables it is hard to see this occurring.

Can Renewables Fill the Gap?

There is no shortage of potential. The UK has a great deal of renewable energy resources, with wind reportedly able to generate one-third of all electricity in a recent week. A comprehensive study by Guidehouse, available via Shell’s Global Energy Resources Database, estimated the total renewable electricity potential in the UK at over 1,000 TWh/year for 2030, with three-quarters of this potential located offshore. This is 3 times the current electricity demand, so would easily cover a doubling of demand often projected under high electrification decarbonisation pathways. If deep ocean offshore wind is included, this potential increases fivefold to over 5,000 TWh. 

The offshore wind sector is a UK success story: the UK today is the global leader in installed capacity and has created significant work and export opportunities for UK businesses in the process. In 2019, the Department for Business, Energy and Industrial Strategy announced a remarkable joint government-industry Offshore Wind Sector Deal to accelerate the UK’s energy transition and transform the UK into a global offshore wind leader. 

The deal foresees cumulative investments into infrastructure of over £40 billion ($52 billion) until 2030, enabled through the long-term certainty set by government strategy, including funds for projects through the Contracts for Difference scheme, with auctions being held every 2 years. 

Up to 30 GW offshore wind target by 2030 is suggested, subject to the industry continuing to reduce costs. Considering that at the end of 2018 the UK had approximately 8.2 GW installed capacity, this means approximately 22 GW needs to be added in the next 12 years. With auctions every 2 years the tender volume will need to be substantial.