Systems in depth
One section per system: its state at evidence close, its exposures and what the operational series will watch.
Contents
- ·Edition home
- ·Executive summary
- 1Advanced nuclear is firm infrastructure and a delivery test
- 2Key findings
- 3Systems and sectors at baseline
- 4Risks and capability
- 5Fuel supply gap while first-of-a-kind units are delayed
- 6Readings from the other desks
- 7The 2027 agenda
- 8Systems in depth
- AMethodology
- BData appendix
- CReferences and record
- ·Complete edition, for print
8.1Reactor designs and deployment
The fleet is large and mature. New designs are at the demonstration stage, with test reactors, one construction permit for a sodium-cooled power reactor and first small units in construction or contract.
| Component | State | Evidence | Status |
|---|---|---|---|
| World fleet | 443 operable and 80 under construction in 2025 | 1 | Reported |
| Test reactors | four DOE-authorized reactors reached zero-power criticality in June and July 2026 | 67 | Reported |
| Small and advanced units | BWRX-300 in construction at Darlington; Rolls-Royce SMR contract for Wylfa; i-SMR design in review; Linglong One in commissioning | 14171819 | Reported |
| Fast and floating reactors | BREST-OD-300 under construction in Russia; two KLT-40S units supplying power since 2019 | 1623 | Reported |
Couplings
- ENE ↔ INF capacity and delivery
- MIN → INF fuel
- FIN → INF construction
Evidence to bind in 2027
- operating record of advanced units
- delivered cost against plan
Related editions
- GLB Global Systems
- GS-02 Energy
- XT-14 Fusion and Frontier Energy
- XT-16 Advanced Energy Storage
- SR-04 Critical Minerals and Strategic Materials
- SR-03 Global Supply Chains, Trade and Chokepoints
8.2Siting, cooling, heat and waste
Reactors need sites, cooling and a route for used fuel. Waste volume of new designs is contested, and the first operating licence for used-fuel disposal was granted in Finland in October 2026.
| Component | State | Evidence | Status |
|---|---|---|---|
| Waste volume | water-, molten-salt- and sodium-cooled small reactors raise waste volume by factors of 2 to 30 in one study | 27 | Reported |
| Repositories | Finland licensed in October 2026; Sweden building on site; France plans commissioning in 2050; the US Yucca Mountain project is suspended | 2122 | Reported |
| Cooling water | not published for new sites in the sources opened | 1 | Expert input |
| Siting | one new unit sited near an existing coal-fired plant | 8 | Reported |
Couplings
- ENE → WAT cooling water
- WAS → GOV repository licensing
- INF → ENE site delivery
Evidence to bind in 2027
- cooling-water and land use of new sites
- waste on a common basis
Related editions
- GLB Global Systems
- GS-02 Energy
- XT-14 Fusion and Frontier Energy
- XT-16 Advanced Energy Storage
- SR-04 Critical Minerals and Strategic Materials
- SR-03 Global Supply Chains, Trade and Chokepoints
8.3Fuel, enrichment and materials
Many new designs need HALEU. Enrichment capacity is concentrated, and the United States restricts imports of Russian low-enriched uranium.
| Component | State | Evidence | Status |
|---|---|---|---|
| HALEU | DOE estimates demand up to 50 tonnes a year by 2035; Piketon had enriched more than 100 kg | 11 | Reported |
| Enrichment capacity | four operators hold nearly all capacity; China values are estimates | 12 | Reported |
| Import limits | US ban on Russian low-enriched uranium from August 2024, with waivers | 12 | Reported |
| Fabrication and materials | capacity by country not bound | 11 | Expert input |
Couplings
- MIN → ENE fuel supply
- TRD → MIN import limits
- FIN → MIN enrichment investment
Evidence to bind in 2027
- HALEU output by year
- fabrication capacity by country
Related editions
- GLB Global Systems
- GS-02 Energy
- XT-14 Fusion and Frontier Energy
- XT-16 Advanced Energy Storage
- SR-04 Critical Minerals and Strategic Materials
- SR-03 Global Supply Chains, Trade and Chokepoints
8.4Economy, cost and workforce
Recent large reactors ran far over first estimates. Small-reactor costs are modelled, contested and not yet delivered.
| Component | State | Evidence | Status |
|---|---|---|---|
| Large units | Vogtle 3 and 4 at USD 30.34 billion against an initial USD 14 billion; Hinkley Point C at GBP 35 billion in 2015 prices | 1517 | Reported |
| Small reactors | none of 15 modelled concepts competed with existing renewables in one study; results depend on assumptions | 2526 | Reported |
| Programme estimates | EPR2 at EUR 72.8 billion for six units; Darlington at CAD 20.9 billion for four | 1420 | Reported |
| Workforce | skills gaps likely; no figure bound | 1 | Expert input |
Couplings
- FIN → INF construction
- ENE → FIN revenue
- HLT → INF workforce
Evidence to bind in 2027
- delivered cost of advanced units
- workforce size and skills gaps
Related editions
- GLB Global Systems
- GS-02 Energy
- XT-14 Fusion and Frontier Energy
- XT-16 Advanced Energy Storage
- SR-04 Critical Minerals and Strategic Materials
- SR-03 Global Supply Chains, Trade and Chokepoints
8.5Safety, licensing and governance watch
Licensing is the main public lever. The United States has published a technology-inclusive framework and set goals, and other regulators are reviewing first designs.
| Component | State | Evidence | Status |
|---|---|---|---|
| Licensing framework | Part 53 final rule published in 2026 | 10 | Reported |
| Executive goals | 400 GW by 2050; 5 GW of uprates and 10 large reactors under construction by 2030 | 34 | Reported |
| Other regulators | Canadian construction licence in April 2025; Korean design review from February 2026 | 1419 | Reported |
| Finance and policy | tripling goal and taxonomy treatment noted; texts not opened | 3441 | Inferred |
Couplings
- GOV → INF licensing pace
- GOV → MIN fuel policy
- GOV → TRD import limits
Evidence to bind in 2027
- review times outside the United States
- text of national policies
Related editions
- GLB Global Systems
- GS-02 Energy
- XT-14 Fusion and Frontier Energy
- XT-16 Advanced Energy Storage
- SR-04 Critical Minerals and Strategic Materials
- SR-03 Global Supply Chains, Trade and Chokepoints
Notes
Numbers are the edition’s reference numbers, so a note reads the same in every chapter. The full list, with every source and its licence, is in Annex C. Annex C, references
- 1World Nuclear Association (ed.), Nuclear Power in the World Today (information library page; 443 operable reactors, 405,667 MWe net, about 9% of world electricity, 80 under construction with 87,813 MWe gross; electricity data for 2025). World Nuclear Association, London. Observation year 2025. Accessed 2026-11-03.back
- 7US Department of Energy (ed.), Department of Energy Celebrates Fourth Criticality Ahead of July 4th Goal (press release, 6 July 2026; Aalo-X, Mark-0, Ward 250 and Unity; zero-power fueled criticality; agency announcement). US Department of Energy, Washington. Observation year 2026. Accessed 2026-11-03.back
- 8US Department of Energy, Office of Nuclear Energy (ed.), NRC Issues Construction Permit for TerraPower’s Natrium Advanced Reactor (article, 9 March 2026; 345 MWe sodium-cooled fast reactor, storage lifts output to 500 MW; Kemmerer Unit 1, Wyoming; operating licence separate). US Department of Energy, Washington. Observation year 2026. Accessed 2026-11-03.back
- 6American Nuclear Society (ed.), The deadline arrives: checking in on the Reactor Pilot Program (news article, 2 July 2026; criticality by Antares 4 June, Valar 18 June, Deployable Energy 1 July; ten companies selected in August 2025; status of the remaining participants). American Nuclear Society, La Grange Park. Observation year 2026. Accessed 2026-11-03.back
- 14World Nuclear Association (ed.), Nuclear Power in Canada (country profile; Darlington BWRX-300, construction licence April 2025, first nuclear concrete 26 June 2026, operation expected 2030, CAD 20.9 billion for four units; page lists 316 MWe gross and describes 300 MWe). World Nuclear Association, London. Observation year 2026. Accessed 2026-11-03.back
- 17World Nuclear Association (ed.), Nuclear Power in the United Kingdom (country profile, first 100,000 characters read; Rolls-Royce SMR delivery contract April 2026 for three Wylfa units with up to GBP 599 million loan financing; Hinkley Point C GBP 35 billion in 2015 prices, February 2026; Sizewell C). World Nuclear Association, London. Observation year 2026. Accessed 2026-11-03.back
- 18World Nuclear Association (ed.), Nuclear Power in China (country profile, first 100,000 characters read; 65 reactors, 65,085 MWe operable; 39 under construction; HTR-PM commercial operation December 2023; Linglong One commissioning expected during 2026; 110 GWe target by 2030). World Nuclear Association, London. Observation year 2026. Accessed 2026-11-03.back
- 19World Nuclear Association (ed.), Nuclear Power in South Korea (country profile; 26 operable units, 25,609 MWe; i-SMR 170 MWe design, standard design approval application February 2026, approval targeted 2028; Barakah units in operation, last in September 2024). World Nuclear Association, London. Observation year 2026. Accessed 2026-11-03.back
- 16POST-CLOSE, context only: World Nuclear Association (ed.), Nuclear Power in Russia (country profile, first 100,000 characters read; 34 operable reactors, 27,969 MWe; BREST-OD-300 under construction since June 2021; Akademik Lomonosov 2 x 32 MWe, grid connection December 2019; Indonesia agreement October 2026). World Nuclear Association, London. Observation year 2026. Accessed 2026-11-03.back
- 23World Nuclear Association (ed.), Advanced Nuclear Power Reactors (information library page, updated November 2025; Generation IV forum set up in 2001 with six concepts; sodium-cooled and lead-cooled fast reactors; molten salt reactors not covered). World Nuclear Association, London. Observation year 2025. Accessed 2026-11-03.back
- 27Krall, L.M., Macfarlane, A.M. and Ewing, R.C., Nuclear waste from small modular reactors, Proceedings of the National Academy of Sciences 119(23), e2111833119, 2022 (open-access full text, abstract and conclusions read; waste volume factors of 2 to 30; three designs). National Academy of Sciences, Washington. Observation year 2022. Accessed 2026-11-03.back
- 21POST-CLOSE, context only: World Nuclear Association (ed.), Nuclear Power in Finland (country profile; Olkiluoto 3 contract of EUR 3.2 billion for mid-2009, regular production April 2023; Onkalo operating licence granted October 2026 valid to the end of 2070, after the 30 September evidence close). World Nuclear Association, London. Observation year 2026. Accessed 2026-11-03.back
- 22World Nuclear Association (ed.), Storage and Disposal of Radioactive Wastes (information library page; Finland, Sweden, France and US repository milestones; Cigéo commissioning planned for 2050; Yucca Mountain suspended). World Nuclear Association, London. Observation year 2026. Accessed 2026-11-03.back
- 11US Department of Energy, Office of Nuclear Energy (ed.), What is high-assay low-enriched uranium (HALEU)? (article of 3 December 2024; enrichment 5% to less than 20% U-235; demand could reach 50 metric tons a year by 2035; Piketon more than 100 kg enriched). US Department of Energy, Washington. Observation year 2024. Accessed 2026-11-03.back
- 12World Nuclear Association (ed.), Uranium Enrichment (information library page; capacity table from the WNA Nuclear Fuel Report 2025: 68.076 million SWU in 2025, Rosatom 29.133, Urenco 17.300, CNNC 13.789 estimated, Orano 7.500; US ban on Russian low-enriched uranium from August 2024). World Nuclear Association, London. Observation year 2025. Accessed 2026-11-03.back
- 15World Nuclear Association (ed.), Nuclear Power in the USA (country profile; 94 operable reactors, 96,952 MWe; Vogtle 3 and 4 cost estimates; Kemmerer permit March 2026; Clinch River construction licence September 2026; Palisades and Crane restart status; page states three reactors critical by July 2026). World Nuclear Association, London. Observation year 2026. Accessed 2026-11-03.back
- 20World Nuclear Association (ed.), Nuclear Power in France (country profile, first 100,000 characters read; 57 operable reactors; EPR2 six units, EUR 72.8 billion estimate of December 2025; Flamanville 3 grid connection December 2024, EUR 13.2 billion estimate of December 2022). World Nuclear Association, London. Observation year 2025. Accessed 2026-11-03.back
- 25Steigerwald, B., Weibezahn, J., Slowik, M. and von Hirschhausen, C., Uncertainties in estimating production costs of future nuclear technologies: a model-based analysis of small modular reactors, Energy 281, 128204, 2023 (abstract page read). Elsevier, Amsterdam. Observation year 2023. Accessed 2026-11-03.back
- 26Steigerwald, B. et al., Future nuclear fission reactors: uncertainties, the effect of parameter choice and an application to small modular reactor concepts, Safety of Nuclear Waste Disposal 2, 217, 2023 (abstract page read; 15 concepts; none competes with existing renewables on its assumptions). Copernicus Publications, Gottingen. Observation year 2023. Accessed 2026-11-03.back
- 3The White House (ed.), Ordering the Reform of the Nuclear Regulatory Commission, Executive Order 14300, 23 May 2025 (goal of 400 GW by 2050 from about 100 GW in 2024; 18-month limit for new reactor decisions; 1-year limit for continued operation). The White House, Washington. Observation year 2025. Accessed 2026-11-03.back
- 10US Nuclear Regulatory Commission (ed.), 10 CFR Part 53 rulemaking page (final rule 91 FR 15696; risk-informed, performance-based, technology-inclusive framework; background in NEIMA and the ADVANCE Act). US Nuclear Regulatory Commission, Rockville. Observation year 2026. Accessed 2026-11-03.back
- 4The White House (ed.), Reinvigorating the Nuclear Industrial Base, Executive Order 14302, 23 May 2025 (5 GW of uprates; 10 new large reactors with complete designs under construction by 2030; fuel, enrichment and spent fuel directions). The White House, Washington. Observation year 2025. Accessed 2026-11-03.back
- 34UNVERIFIED, not opened: Declaration to Triple Nuclear Energy, COP28, December 2023, cited from memory without a figure. Signatory national governments. Observation year 2023. Accessed 2026-11-03.back
- 41UNVERIFIED, not opened: European Commission (ed.), Complementary Climate Delegated Act on nuclear and gas activities in the EU taxonomy, 2022, cited from memory without a figure. European Commission, Brussels. Observation year 2022. Accessed 2026-11-03.back
