The UK needs new low-carbon electricity generation to replace current ageing plant, and to meet the commitment to reduce net greenhouse gas emissions to zero by 2050.
With UK electricity demand likely to quadruple by 2050 as transport and heating are decarbonised, the UK will potentially need to quadruple its low-carbon generation.
The UK currently has 15 reactors on eight sites, with a total generating capacity of around 9 gigawatts of electricity (GWe), operated by EDF. These stations generate around a fifth of the UK’s electricity, or around 65 terawatt-hours (TWh) a year.
All but one are advanced gas-cooled reactors build over the 1960s–80s, and scheduled to be retired over 2022–30. The exception is Sizewell B, the UK’s only pressurised water reactor (PWR), which began operations in 1995 and is scheduled for decommissioning in 2035.
Four reactor designs have been or are being formally considered for UK new build: the Framatome EPR (originally the Areva European Pressurised Reactor), Westinghouse’s AP1000, Hitachi-GE’s Advanced Boiling Water Reactor (ABWR), and the Chinese Hualong HPR1000.
Both the EPR and AP1000 are generation III+ PWRs, offering a range of safety, economic and operational improvements over previous designs.
The EPR has an output of 1600MWe. Four EPRs are under construction in Finland, France and China, with the first in China entering commercial operation in late 2018.
The AP1000 has an output of 1150MWe. AP1000s are under construction or operational at two sites in China (with first generation in 2018) and two sites in the US.
Both the EPR and AP1000 have completed a generic design assessment (GDA) by the Office for Nuclear Regulation (ONR) and Environment Agency. This assessment is intended to support the construction of a number of new nuclear power stations by approving a standard reactor design which can be built in different locations by different developers. Each build will still require a site-specific licence.
The Hitachi-GE ABWR is a significantly different design to the Areva and Westinghouse PWRs, operating at lower pressures and temperatures but requiring much larger pressure vessels. The 1300MWe ABWR completed GDA in December 2017. Four ABWRs are already in operation in Japan.
The 1170MWe Hualong HPR1000 is a generation III PWR, currently being deployed at three sites in China. It completed the third phase of GDA in February 2020, with CGN aiming for approval around 2022.
The UK is also considering the development of small modular reactors based on Gen III+ technologies, with the first potentially online by 2030, as well as new designs of advanced modular reactors based on Gen IV technologies. None have yet entered GDA.
See the ONR’s GDA pages for the latest information.