Small Nuclear Reactors: Can Fission Make a Comeback?
In 2026 nuclear power is making a different kind of news. On 13 April the UK signed a contract for three Rolls-Royce small modular reactors at Wylfa, on Anglesey. Ten days later TerraPower began building its Natrium reactor at Kemmerer, Wyoming. And Three Mile Island's undamaged Unit 1 is being restarted as the Crane Clean Energy Center, with Microsoft buying its power.
This video explains how a fission reactor turns splitting atoms into electricity, and why the West almost stopped building them: the boom that began at Calder Hall in 1956, and the accidents at Three Mile Island (1979), Chernobyl (1986) and Fukushima (2011). It shows why big reactors became so expensive, with Vogtle, Flamanville and Hinkley Point C, now estimated by EDF at £35bn in 2015 prices with Unit 1 in 2030.
Small reactors could fix some of nuclear's problems, but not waste, fuel supply or the cost of the first of a kind. The video ends with the dates to watch to 2030. Photos are public domain, credited on screen.
Educational documentary. Not financial or investment advice.
In these topics
Tags
Chapters
- Why fission is back in the news
- How a reactor makes electricity
- The atomic age boom
- Three accidents
- Why big nuclear got so expensive
- Hinkley Point C
- The small modular idea
- The designs racing to be first
- The first warning: NuScale in Utah
- The builds now under way
- AI data centres as customers
- Forwards or backwards?
Sources and credits
Photo credits (Wikimedia Commons)
- Calder Hall nuclear power station, the world's first commercial-scale nuclear plant (US DOE photo, c.1973): ENERGY.GOV, Public domain - https://commons.wikimedia.org/wiki/File%3ACalder_Hall_nuclear_power_station_%2811823864155%29.jpg
- Three Mile Island nuclear generating station, 1979 (US DOE): United States Department of Energy, Public domain - https://commons.wikimedia.org/wiki/File%3AThree_Mile_Island_%28color%29.jpg
Primary sources
- gov.uk, Great British Energy - Nuclear and Rolls-Royce SMR sign contract, 13 April 2026 - at least 1.4 GWe; £2.6bn in the 2025 Spending Review. Rolls-Royce release of the same date; WNN, 13 Apr 2026 (470 MWe units, FID 2029).
- ONR, Rolls-Royce SMR GDA Step 2 summary report, 29 July 2024 - GDA expected to complete December 2026 (re-); Environment Agency GDA Step 2 report, 30 July 2024.
- WNN, UK marks 60th anniversary of Calder Hall, 18 Oct 2016; US DOE, December 23, 1957: Shippingport; IAEA, Nuclear Power Reactors in the World, RDS-2, 2025 edition, Table 7; EIA Today in Energy, 27 Apr 2017.
- US NRC, Backgrounder on the Three Mile Island Accident (quoted); IAEA, The Fukushima Daiichi Accident, Report by the Director General, 2015; BASE (Germany), nuclear phase-out.
- EIA Today in Energy, 1 May 2024 (Vogtle); Georgia Power, 29 Apr 2024; Cour des comptes, La filiere EPR, 14 Jan 2025 (via AFP / Connaissance des Energies); Nuclear Regulatory Review 2025 (Fingleton), 24 Nov 2025 (quoted); MIT, The Future of Nuclear Energy in a Carbon-Constrained World, 2018.
- National Audit Office, Hinkley Point C, 23 June 2017; EDF, Hinkley Point C update, 23 Jan 2024; EDF 2025 annual results, 20 Feb 2026.
- Rolls-Royce, Small Modular Reactors (90% factory, truck/train/barge, two football pitches); TerraPower, 4 Mar 2026 and 23 Apr 2026 (quoted); US DOE, 9 Mar 2026; NuScale SEC filing, 5 Aug 2026.
- Utility Dive, 9 Nov 2023; UAMPS/NuScale joint release, 8 Nov 2023 (quoted).
- World Nuclear News, 23 May 2025 (Darlington costs); CNSC Darlington New Nuclear Project page (25 Aug 2026); ANS Nuclear Newswire, 5 Jun 2026; GE Vernova MoU release, 22 Sep 2026.
- IEA, Energy and AI, April 2025; Constellation, 20 Sep 2024 (quoted) and 18 Nov 2025; WNN, 1 Apr 2026; Google, 14 Oct 2024; X-energy, 16 Oct 2024; Meta, 9 Jan 2026.
- WNN, HALEU fuel availability delays Natrium reactor project, 15 Dec 2022; Posiva, 4 Aug 2026; Nuclear Waste Services (Mid and South Copeland).
Not regulated financial advice.