Nuclear power in the United Kingdom (UK): history and prospects

The UK is one of the pioneers in the development and use of nuclear power for electricity generation. The breakdown of different sources of electricity generation in the UK in 2020 was as follows: 37% renewables (wind, solar, biomass, hydro), 41% natural gas, 16% nuclear and 6% other sources [1]. This article focuses on nuclear power generation in the UK, outlining its history, the reactor technologies used and the innovative power plant and reactor projects currently under development.

History of nuclear power generation in the UK

The history of nuclear power in the UK dates back to the 1950s, when the country began developing nuclear reactors for civil use. The first research reactor, ZEEP, was commissioned in 1947 [2]. The country’s first power reactor, Calder Hall Nuclear Power Station, was commissioned in 1956 and is considered the world’s first commercial nuclear power plant [3].

Over the years, the UK has built up a fleet of nuclear reactors, culminating in 26 reactors in 1990 [4]. Since then, several reactors have been decommissioned due to age and technical problems. By 2021, the country was operating 15 reactors across 7 sites, supplying around 16% of the country’s electricity [5].

Nuclear reactor technologies used in the UK

The UK is particularly well known for having developed and used advanced gas-cooled reactors (AGRs) and pressurized water reactors (PWRs) [6].

1. Advanced gas-cooled reactors (AGRs): AGR reactors are a specific British technology that uses graphite as a moderator and carbon dioxide as a coolant. AGRs are designed to operate at higher temperatures than first-generation gas-cooled reactors, offering greater energy efficiency. Most of the nuclear reactors in operation in the UK are AGRs [7].
2. Pressurized water reactors (PWRs): The UK also has a pressurized water reactor, Sizewell B nuclear power station, which was commissioned in 1995 [8]. Pressurized water reactors are widely used around the world, and operate using water as moderator and coolant. The water is kept under pressure to prevent boiling, and the steam produced in a secondary steam generator powers turbines to generate electricity.

Innovative power plant and reactor projects in the UK

The UK continues to develop innovative power plant and reactor projects to maintain and strengthen its nuclear fleet. These include the construction of new reactors, research into Small Modular Reactors (SMRs) and Generation IV reactors.

1. New reactor construction: The UK government has approved the construction of new nuclear reactors to replace aging facilities and meet growing demand for electricity. The Hinkley Point C project, currently under construction, is a new-generation nuclear power plant equipped with two pressurized water reactors of French origin (EPR) [9]. Scheduled for completion by 2025, it will supply around 7% of the country’s electricity.
2. Small Modular Reactors (SMR): The UK is also interested in developing small modular reactors, which are new-generation reactors that are more compact and modular, offering enhanced safety and having a low environmental impact [10]. SMRs could be a viable option for replacing aging reactors and complementing intermittent renewable energy sources, such as wind and solar. Rolls-Royce is working on the development of a UK-specific SMR, which could be deployed by the early 2030s [11].
3. Generation IV reactors: the UK is participating in international research and development initiatives on Generation IV reactors, which aim to develop safer, more efficient and more sustainable nuclear technologies [12]. Generation IV reactors offer significant improvements over current reactors in terms of safety, waste management and resource utilization.

In conclusion, the UK has a long history of nuclear power generation and continues to play an important role in the development of new nuclear technologies. Innovative power plant and reactor projects, such as Hinkley Point C, small modular reactors and Generation IV reactors, demonstrate the UK’s commitment to innovation and safety in the nuclear energy sector.

Nuclear reactors in the UK

Countries producing nuclear power

Sources :

• [1] Department for Business, Energy & Industrial Strategy (2021). Digest of United Kingdom Energy Statistics (DUKES). https://www.gov.uk/government/statistics/digest-of-uk-energy-statistics-dukes-2021
• [2] World Nuclear Association. (2021). Nuclear Power in the United Kingdom. https://www.world-nuclear.org/information-library/country-profiles/countries-t-z/united-kingdom.aspx
• [3] Ibid.
• [4] Ibid.
• [5] Ibid.
• [6] Ibid.
• [7] Ibid.
• [8] Ibid.
• [9] Hinkley Point C. (2021). Hinkley Point C Project. https://www.edfenergy.com/energy/nuclear-new-build-projects/hinkley-point-c
• [10] World Nuclear Association. (2021). Small Nuclear Power Reactors. https://www.world-nuclear.org/information-library/nuclear-fuel-cycle/nuclear-power-reactors/small-nuclear-power-reactors.aspx
• [11] Rolls-Royce (2021). UK Small Modular Reactor (SMR). https://www.rolls-royce.com/products-and-services/nuclear/uk-smr.aspx
• [12] Generation IV International Forum. (2021). United Kingdom. https://www.gen-4.org/gif/jcms/c_9362/united-kingdom