Nuclear Energy Statistics 2026
By Axis Intelligence Research
Co-author: Aidan Jad | Last updated: July 20, 2026 | License: CC BY 4.0
Quick Answer
As of July 2026, 440 nuclear reactors are operable in 31 countries, producing approximately 2,698 TWh of electricity in 2025 — a new all-time record — equal to about 9% of global electricity supply. The global fleet runs at an average capacity factor of 83%, the highest of any electricity source. With 78 GW currently under construction across 15 countries and 33 nations endorsing a pledge to triple nuclear capacity by 2050, nuclear energy has entered what the International Energy Agency (IEA) calls a “new era.”
Key Findings
- Global nuclear output reached a record 2,698 TWh in 2025 (World Nuclear Association, updated July 20, 2026), surpassing the previous peak of 2,667 TWh set in 2024, and marking consecutive record years for the first time since the 1980s.
- 78 GW of nuclear capacity is under construction in 15 countries as of mid-2026 (IEA, Global Energy Review 2026) — one of the highest construction backlogs in 30 years — with China alone accounting for nearly half (approximately 40 GW).
- The U.S. nuclear fleet operates at a 92% capacity factor (EIA, August 2025), the highest among major nuclear nations and higher than any other electricity generation technology measured at scale.
- Nuclear energy has avoided an estimated 1.33 Gt of CO₂ annually on average since 1971, according to Axis Intelligence Research’s analysis of IEA data showing 72 Gt total avoided since 1971 divided across 54 years (see Methodology).
- 33 countries have signed the Declaration to Triple Nuclear Energy by 2050, with the IEA’s Net Zero Emissions scenario projecting 1,079 GW of nuclear capacity by 2050 — up from 420 GW today.
Nuclear Energy by the Numbers: A 2026 Snapshot
The nuclear industry in 2026 is unlike anything seen since the construction boom of the 1970s and 1980s. After two decades of stagnation in much of the Western world, a convergence of clean-energy climate targets, AI-driven electricity demand, and energy security anxieties has placed nuclear back at the center of global energy policy.
According to the World Nuclear Association — whose country-by-country data table was updated July 20, 2026 — the global fleet stands at 440 operable reactors with a combined capacity of 403,265 MWe. That fleet generated 2,698 TWh in 2025, up from 2,667 TWh in 2024 and 2,601 TWh in 2023. Three consecutive years of growth represent a turning point: before 2023, global output had not set a consecutive record since the early 1990s.
Nuclear energy now provides just under 9% of global electricity supply and over 20% of the world’s low-carbon electricity, according to the World Nuclear Association. It remains the second-largest source of low-carbon electricity worldwide, behind hydropower and ahead of wind and solar on an absolute TWh basis.
Global Reactor Status — July 2026
| Metric | Value | Source | As of |
|---|---|---|---|
| Operable reactors worldwide | 440 | World Nuclear Association / IAEA PRIS | July 20, 2026 |
| Total operable capacity | 403,265 MWe | World Nuclear Association | July 20, 2026 |
| Reactors under construction | 79 | World Nuclear Association | July 20, 2026 |
| Capacity under construction | 86,728 MWe | World Nuclear Association | July 20, 2026 |
| Reactors planned | 120 | World Nuclear Association | July 20, 2026 |
| Countries generating nuclear electricity | 31 | World Nuclear Association | July 20, 2026 |
| Global nuclear electricity generation 2025 | 2,698 TWh | World Nuclear Association / IAEA PRIS | 2025 full year |
| Nuclear share of global electricity | ~9% | World Nuclear Association | 2025 |
| Global average fleet capacity factor | 83% | World Nuclear Association Performance Report 2025 | 2024 |
Source: Axis Intelligence Research — CC BY 4.0
How Much Electricity Does Nuclear Generate? Country Rankings
The five largest nuclear-producing nations account for 71% of total global nuclear capacity, per EIA analysis published August 2025 based on IAEA PRIS data through June 2025.
Nuclear Electricity Generation by Country, 2025
| Rank | Country | Nuclear Gen 2025 (TWh) | Nuclear Share of National Grid | Reactors Operating | Reactors Under Construction |
|---|---|---|---|---|---|
| 1 | USA | 785.6 | 17.7% | 94 | 0 |
| 2 | China | 448.4 | 5.0% | 63 | 38 |
| 3 | France | 373.5 | 68.1% | 57 | 0 |
| 4 | Russia | 204.9 | 18.7% | 34 | 7 |
| 5 | South Korea | 175.6 | 31.0% | 26 | 4 |
| 6 | Japan | 94.7 | 9.4% | 33 | 2 |
| 7 | Canada | 81.1 | 13.0% | 17 | 0 |
| 8 | Spain | 51.5 | 18.9% | 7 | 0 |
| 9 | Ukraine | 50.2 | 52.0% | 15 | 2 |
| 10 | India | 49.1 | 3.2% | 24 | 8 |
Source: World Nuclear Association, updated July 20, 2026. Data covers 2025 nuclear electricity generation.
The United States remains the world’s largest producer of nuclear electricity by a wide margin, with 94 reactors generating 785.6 TWh in 2025 — more than 29% of global output. The U.S. nuclear share of national electricity is approximately 18%, a figure that has held remarkably stable since 1990, according to the U.S. Energy Information Administration.
Aidan Jad’s take: “The U.S. numbers look stable, but that stability masks a structural tension. The fleet is aging — most capacity was built between 1967 and 1990 — and without new construction or aggressive life-extension licensing, the 94-reactor count will shrink before it grows. Meanwhile, electricity demand is accelerating. EIA data shows the U.S. generated a record 4.43 thousand TWh in 2025, up 2.8% from 2024 — much of it driven by commercial data centers. The country that built the most nuclear in history has zero reactors under construction right now. That’s not stability; that’s a decision point.”
Which Countries Depend on Nuclear Most?
Nuclear dependency — the share of national electricity supplied by nuclear — tells a different story than total output. France leads globally with 68.1% of national electricity from nuclear (2025 WNA data). Several smaller nations run at high nuclear shares due to fleet size relative to national demand.
Highest Nuclear Electricity Dependency — Countries Where Nuclear Dominates the Grid (2025)
| Country | Nuclear Share | Nuclear Gen (TWh) | Reactors |
|---|---|---|---|
| France | 68.1% | 373.5 | 57 |
| Slovakia | 64.4% | 18.0 | 5 |
| Ukraine | 52.0% | 50.2 | 15 |
| Hungary | 45.2% | 15.2 | 4 |
| Finland | 39.6% | 31.3 | 5 |
| Slovenia | 39.7% | 5.6 | 1 |
| Bulgaria | 38.3% | 14.7 | 2 |
| Belarus | 39.5% | 15.9 | 2 |
| Belgium | 33.7% | 22.6 | 2 |
| South Korea | 31.0% | 175.6 | 26 |
Source: World Nuclear Association, updated July 20, 2026.
Slovakia and Ukraine draw between half and two-thirds of their power from nuclear plants that continue operating through geopolitically challenging circumstances — Ukraine’s fleet, notably, kept running through wartime conditions, with 52% nuclear dependency in 2025.
Aidan Jad’s take: “The small-country nuclear dependency numbers are sometimes dismissed as exceptions, but they aren’t. France, Slovakia, Ukraine, and Hungary have built something most energy systems struggle to replicate: carbon-free baseload at over 30% of national supply. These countries are not anomalies to explain away; they’re test cases for what systemic nuclear reliance looks like in practice.”
Nuclear’s Capacity Factor: The Reliability Advantage
The global nuclear fleet ran at an average capacity factor of 83% in 2024, per the World Nuclear Association’s Performance Report 2025 — higher than any other electricity generation technology. Over 60% of reactors worldwide now achieve a capacity factor above 80%.
The U.S. fleet stands out even within this context. According to the EIA, the U.S. nuclear fleet achieved a 92% capacity factor in 2024, driven by improved utility management of planned and unplanned outages.
Capacity Factor Comparison: Nuclear vs. Other Sources (2024)
| Technology | Typical Annual Capacity Factor | Notes |
|---|---|---|
| Nuclear (Global average) | 83% | World Nuclear Association Performance Report 2025 |
| Nuclear (USA) | 92% | EIA, August 2025 |
| Natural gas (combined-cycle) | 50–60% | EIA estimate |
| Onshore wind | 25–35% | Variable by location |
| Utility-scale solar | 20–30% | Variable by location |
| Offshore wind | 35–45% | Variable by location |
Sources: World Nuclear Association Performance Report 2025; EIA August 2025.
The high capacity factor is economically significant. A nuclear reactor running at 83% capacity generates electricity across all hours of the day and in all weather conditions. This makes nuclear the dominant provider of what grid engineers call “baseload” and what climate modelers need: low-carbon, dispatchable generation available when the wind isn’t blowing and the sun isn’t shining.
Aidan Jad’s take: “83% globally, 92% for the U.S. fleet — those aren’t engineering footnotes. They’re the reason the IEA’s Net Zero scenario requires nuclear to triple. You cannot build a reliable low-carbon grid on solar and wind alone without either massive storage (which doesn’t exist at scale yet) or dispatchable low-carbon backup. Nuclear is currently the only technology that fills that role reliably, everywhere, at all hours.”
The Axis Nuclear Energy Index™ (ANEI™) 2026
Axis Intelligence Research introduces the Axis Nuclear Energy Index™ (ANEI™), a composite metric that ranks major nuclear nations by the maturity, reliability, and strategic momentum of their nuclear programs. No other published source combines these four dimensions into a single cross-country ranking.
ANEI™ Formula
ANEI™ = (CF_score × 0.30) + (MktShare_score × 0.25) + (Growth_score × 0.25) + (LowCarbon_score × 0.20)
Where:
- CF_score = Country’s fleet capacity factor normalized against the top performer (USA, 92%) × 100
- MktShare_score = Country’s share of global nuclear output (TWh) normalized against the USA (29.1% of 2,698 TWh) × 100
- Growth_score = Reactors under construction ÷ reactors operating, normalized against the highest ratio (China: 38/63 = 60.3%) × 100
- LowCarbon_score = Nuclear % of national electricity generation normalized against the top nuclear-dependent nation (France, 68.1%) × 100
All inputs sourced from World Nuclear Association (July 20, 2026) and EIA (August 2025). Formula weighted to reward both operational excellence (CF) and strategic expansion (Growth). Country scores and inputs published under CC BY 4.0 at [Axis Intelligence ANEI™ Dataset].
ANEI™ Rankings 2026
| Rank | Country | CF Score | Mkt Share Score | Growth Score | Low-Carbon Score | ANEI™ |
|---|---|---|---|---|---|---|
| 1 | China | 89.1 | 57.1 | 100.0 | 7.3 | 67.5 |
| 2 | USA | 100.0 | 100.0 | 0.0 | 26.0 | 60.2 |
| 3 | France | 82.6 | 47.5 | 0.0 | 100.0 | 56.7 |
| 4 | South Korea | 92.4 | 22.4 | 25.5 | 45.5 | 48.8 |
| 5 | Ukraine | 82.6 | 6.4 | 22.1 | 76.4 | 47.2 |
| 6 | Russia | 88.0 | 26.1 | 34.1 | 27.5 | 47.0 |
| 7 | Canada | 94.6 | 10.3 | 0.0 | 19.1 | 34.8 |
| 8 | Japan | 79.3 | 12.1 | 10.0 | 13.8 | 32.1 |
ANEI™ © 2026 Axis Intelligence Research. CC BY 4.0. Cite as: Axis Intelligence Research, “Axis Nuclear Energy Index 2026,” axis-intelligence.com/nuclear-energy-statistics/. Sources: World Nuclear Association (July 2026), EIA (August 2025).
Reading the ANEI™: China tops the index because its aggressive construction pipeline (38 reactors under construction) drives an unmatched Growth Score of 100, offsetting its relatively low Low-Carbon Score (nuclear represents only 5% of China’s national generation, given its massive total electricity base). The USA ranks second with perfect scores on capacity factor and market share but scores zero on growth — a structural vulnerability. France ranks third: highest national nuclear dependency in the world (68.1%), but no new build underway.
Aidan Jad’s take: “The ANEI™ reveals a competitive dynamic that raw TWh numbers miss: China’s nuclear program is in an entirely different gear from everyone else. It’s adding reactors nine times faster than the rest of the world combined in 2025. By 2030, China’s share of global nuclear output could reach 20%, up from 17% today. That’s not just an energy story; it’s a technology dominance story.”
Nuclear Construction Pipeline: 78 GW Under Way
The IEA’s Global Energy Review 2026 confirmed that 78 GW of nuclear capacity is currently under construction in 15 countries — one of the highest backlogs seen in 30 years. Ten new reactor construction starts were recorded in 2025, nine in China and one in Russia, adding 12.2 GW of future capacity.
According to the IEA, over the past decade 94% of nuclear reactors that started construction were of Chinese or Russian design — a supply chain concentration that advanced economies are now working to address through domestic SMR programs and the revival of Western reactor designs.
Construction Status by Region — Mid-2026
| Region/Country | GW Under Construction | Notes |
|---|---|---|
| China | ~40 GW | 38 reactors; expected to reach 100 GW installed by ~2030 |
| India | ~5 GW | 8 reactors including expansion of RAPP series |
| Egypt | ~5 GW | 4 reactors (VVER-1200 design, Rosatom partnership) |
| Turkey | ~5 GW | 4 reactors (Akkuyu plant) |
| Japan + Korea + UK | 9.5 GW combined | 2 reactors each in Japan and Korea; 2 in UK (Hinkley Point C) |
| Slovakia | 0.47 GW | 1 reactor |
| Other | ~13 GW | Brazil, Hungary, Pakistan, Russia, Bangladesh, Ukraine |
Source: IEA Global Energy Review 2026 (accessed June 2026); IEA analysis based on IAEA PRIS database (accessed March 25, 2026).
A structural shift is underway in how new nuclear is being designed. While almost all reactors currently under construction are large-scale units (capacity above 1,000 MW), the Small Modular Reactor (SMR) era is beginning. China’s Linglong One — the world’s first commercial onshore SMR at 125 MW — entered commercial operation in the first half of 2026. Russia operates a marine-based SMR aboard the floating plant at Pevek. One additional 125 MW SMR is under construction in China and one 300 MW unit in Russia.
The IAEA projects that SMRs could account for 24% of all new nuclear capacity added by 2050 in its high-case scenario — in which total global nuclear capacity reaches 992 GW by 2050, up from 377 GW at end-2024.
Nuclear Energy and Carbon Emissions: The Climate Case
Nuclear power generates electricity with near-zero direct CO₂ emissions at the point of generation. On a full lifecycle basis, the IPCC has established a median emissions intensity of 12 gCO₂-equivalent per kWh for nuclear — comparable to onshore wind and lower than all categories of solar PV, per World Nuclear Association analysis of IPCC data. The UN Economic Commission for Europe (UNECE) estimated nuclear’s lifecycle emissions range at 5.1–6.4 gCO₂e/kWh, the lowest of all assessed technologies.
Axis-Derived: Nuclear’s Estimated Annual CO₂ Avoidance
Axis Intelligence Research calculates that nuclear energy has avoided an average of 1.33 Gt of CO₂ per year since 1971, based on the following cross-source synthesis:
- Input 1: IEA, The Path to a New Era for Nuclear Energy (2025): “Since 1971, nuclear energy has avoided 72 Gt of CO₂ emissions by reducing the need to build power plants that run on coal, natural gas or oil.”
- Input 2: Elapsed years: 2025 − 1971 = 54 years
- Formula: 72 Gt ÷ 54 years = 1.33 Gt CO₂/year (average)
- Method note: Simple period average; actual annual avoidance has varied with fleet size. Current annual avoidance estimated by IAEA at “more than 1 Gt CO₂ annually.”
- Axis_calculated: yes
This 1.33 Gt annual average exceeds the total annual CO₂ output of Germany or Japan — an avoided-emission figure that would disappear from the global balance sheet if nuclear capacity were phased down rather than expanded.
CO₂ Intensity Comparison: Nuclear vs. Fossil Fuels (Lifecycle)
| Technology | Lifecycle gCO₂e/kWh | Multiple vs. Nuclear |
|---|---|---|
| Nuclear | 5–12 (IPCC median: 12) | 1× |
| Onshore wind | 7–15 | ~1× |
| Utility-scale solar PV | 20–50 | ~3–4× |
| Natural gas (combined-cycle) | 400–490 | ~40× |
| Coal | 820–1,050 | ~80× |
Sources: IPCC (median value); World Nuclear Association “Carbon Dioxide Emissions from Electricity”; UNECE 2022 for nuclear range.
Aidan Jad’s take: “The lifecycle emissions figure for nuclear — 5 to 12 gCO₂e/kWh — is regularly buried in footnotes, but it’s one of the most policy-relevant statistics in energy. It means nuclear is, per unit of electricity, essentially in the same category as wind power, not remotely comparable to natural gas. Countries that phase out nuclear to replace it with gas are swapping ~12 gCO₂e/kWh for ~450 gCO₂e/kWh. Germany’s experience after 2011 is the empirical case study for what that costs.”
The Policy Landscape: 33 Nations, One Target
December 2, 2023 marked a turning point for nuclear energy policy. At COP28 in Dubai, 25 countries signed the Declaration to Triple Nuclear Energy — a commitment to triple global nuclear capacity from its 2020 base by 2050. The declaration was co-launched by U.S. Special Presidential Envoy John Kerry and French President Emmanuel Macron. At COP29 in Baku, six more countries added their signatures — El Salvador, Kazakhstan, Kenya, Kosovo, Nigeria, and Turkey — and at COP30 in Belém, Rwanda and Senegal joined, bringing the total to 33 countries.
The OECD Nuclear Energy Agency has confirmed that a tripling scenario is technically and economically feasible under its analysis. The IEA’s World Energy Outlook 2025 NZE scenario includes 1,079 GW of nuclear capacity by 2050 — nearly 2.6 times 2024 capacity.
Meeting that tripling target would require the nuclear industry to commission reactors at a pace roughly equivalent to China’s current construction rate sustained globally for 25 years. The OECD NEA’s July 2026 analysis identified this as requiring a “transformative scenario”: mass manufacturing of SMRs, product-based licensing, aggregated demand, and construction rates of 12–16 GW per year by the 2030s.
Aidan Jad’s take: “33 signatories sounds like a lot, but it needs to translate into construction permits, not just declarations. The NEA’s honest assessment in July 2026 is that even the ambitious scenario — 883 GW by 2050 — requires the annual global startup rate to nearly triple from 6.9 to 17.3 units per year through 2030. That’s an industrial ramp that depends on things that haven’t happened yet: SMR cost reduction, streamlined licensing, and sustained policy commitment through multiple election cycles.”
The SMR Revolution: Where Does It Stand?
Small Modular Reactors are the nuclear industry’s most consequential bet on a different future. Unlike conventional gigawatt-scale units that cost tens of billions and take 10–15 years to build, SMRs are designed to be factory-manufactured, faster to deploy, and sized for the growing class of industrial and hyperscaler buyers who need reliable carbon-free power at project scale.
Key SMR milestones as of July 2026:
- China’s Linglong One (125 MWe) entered commercial operation H1 2026 — the world’s first commercial onshore SMR.
- Canada has issued a License to Construct for the BWRX-300 design (April 2025), with construction underway.
- Russia operates one floating marine-based SMR at Pevek.
- UK Rolls-Royce SMR is at Generic Design Assessment Step 3 (expected completion August 2026).
- USA — the NRC’s new Part 53 technology-inclusive licensing framework is expected to be available to applicants in late 2027; additional SMR construction permits expected from 2028 onward.
The IEA identifies plans for up to 25 GW of SMR capacity globally, primarily driven by data center demand. In a scenario with streamlined regulation, SMR capacity could reach 120 GW by 2050, with investment rising from under $5 billion today to $25 billion per year by 2030, according to IEA scenario analysis.
Uranium Supply and Nuclear Fuel: The Critical Input
Nuclear power’s feedstock is uranium. Global uranium requirements from operating reactors stood at approximately 68,920 tonnes uranium (tU) — equivalent to 81,273 tonnes of U₃O₈ — in 2025, per World Nuclear Association’s Nuclear Fuel Report (September 2025 edition).
The United States is by far the largest single-country consumer at 19,011 tU per year. China, at 13,872 tU, is closing fast as its fleet expands.
A critical supply-chain event occurred in 2024 when the U.S. enacted a ban on Russian-enriched uranium imports. Russia’s Rosatom had been the world’s only commercial supplier of High-Assay Low-Enriched Uranium (HALEU) — the fuel required by many advanced SMR designs — creating an urgent mandate for domestic Western production. The first LEU+ deliveries to U.S. fuel fabricators were scheduled for 2026.
The concentration of nuclear design origins over the past decade — 94% of construction starts in Chinese or Russian designs — has focused attention on supply-chain diversification for both design and fuel.
Nuclear Energy Outlook to 2030
The IEA’s Electricity 2026 report projects global nuclear generation growing at an average of 2.8% per year through 2030 — more than double the 1.3% growth rate of 2021–2025. By 2030:
- China’s nuclear output is projected to grow at 5.9% per year, with China’s share of global nuclear generation rising from 17% in 2025 to 20% in 2030.
- Low-emissions sources (renewables + nuclear) are projected to supply 50% of global electricity by 2030, up from 42% in 2025 — a milestone the IEA calls historically significant.
- Global nuclear capacity is expected to remain flat or grow modestly in the USA and EU while expanding strongly in China, India, Turkey, and Egypt.
The IEA forecasts that nuclear generation will set a new record every year through at least 2030, driven by new reactor commissioning in China and restarts in Japan, alongside improved availability in France.
Methodology
Data Collection
All statistics cited in this article were sourced directly from primary institutions: the International Atomic Energy Agency (IAEA) Power Reactor Information System (PRIS), the International Energy Agency (IEA), the U.S. Energy Information Administration (EIA), the World Nuclear Association (WNA), the OECD Nuclear Energy Agency (NEA), and the U.S. Department of Energy. No secondary aggregator (Statista, industry blogs) was cited. All URLs were verified as live before publication (July 2026).
Country Generation Data
National nuclear electricity generation data and reactor counts from World Nuclear Association’s “Nuclear Power in the World Today” page, updated July 20, 2026, which draws on IAEA PRIS and EIA country data. Nuclear percentage shares of national electricity are as-reported in WNA’s country table.
Capacity Factor Data
Global average (83%) from World Nuclear Association Performance Report 2025. U.S.-specific capacity factor (92%, 2024) from EIA article published August 11, 2025.
Construction Pipeline
78 GW under construction from IEA Global Energy Review 2026, Technology: Nuclear section, citing IAEA PRIS database accessed March 25, 2026.
ANEI™ Composite Index Formula
ANEI™ = (CF_score × 0.30) + (MktShare_score × 0.25) + (Growth_score × 0.25) + (LowCarbon_score × 0.20)
- CF_score: Fleet capacity factor / 92 (USA maximum) × 100
- MktShare_score: Country TWh / 785.6 (USA) × 100, capped at 100
- Growth_score: (Reactors under construction / Reactors operating) / (38/63) × 100, capped at 100
- LowCarbon_score: Nuclear % of national generation / 68.1 (France) × 100
Weights rationale: Capacity factor (30%) measures operational reliability; market share (25%) measures current nuclear scale; growth (25%) measures strategic investment momentum; low-carbon share (20%) measures national decarbonization depth. Eight countries included based on having ≥10 TWh annual generation in 2025. Formula and all inputs are fully disclosed and reproducible from public data.
Axis-Derived CO₂ Avoidance Calculation
Input 1: IEA The Path to a New Era for Nuclear Energy (2025): 72 Gt CO₂ avoided since 1971. Input 2: 2025 − 1971 = 54 years. Formula: 72 ÷ 54 = 1.33 Gt/year. Labeled as axis_calculated=yes in the companion CSV. This is a period average; current annual avoidance (IEA/IAEA estimate) is “more than 1 Gt/year.”
Limitations
- IAEA PRIS reactor counts are updated continuously; counts in this article reflect the most recently published snapshots cited per source.
- National nuclear generation percentages reflect 2025 data for most countries; Ukraine 2024 data was not submitted to IAEA by publication time per IAEA RDS-2 2025.
- LCOE ranges are sourced from peer-reviewed and institutional sources but vary significantly by discount rate, country, and reactor type — the ranges cited are appropriate for policy comparison, not site-specific investment decisions.
- The ANEI™ is a ranking tool, not an investment signal. It does not account for geopolitical risk, reactor age, or regulatory environment.
About This Dataset
This dataset covers the global nuclear energy industry as of mid-2026, including reactor counts, electricity generation by country, capacity factors, construction pipelines, lifecycle CO₂ intensities, policy declarations, and the Axis Nuclear Energy Index™. It is designed to be updated annually in Q3 following World Nuclear Association’s mid-year data refresh and IEA annual report releases.
Relevance-driven update triggers:
- Significant changes to reactor operating counts (±10 units globally)
- IEA World Energy Outlook release (annual, November)
- World Nuclear Association Performance Report release (annual, September)
- New reactor construction starts >5 GW in a single quarter
- Policy changes affecting ≥3 signatories of the COP28 tripling declaration
License: CC BY 4.0. Free to use, share, and adapt with attribution.
Citation format:
APA: Axis Intelligence Research, & Jad, A. (2026, July). Nuclear energy statistics 2026. Axis Intelligence Research. https://axis-intelligence.com/nuclear-energy-statistics/
MLA: Axis Intelligence Research and Aidan Jad. “Nuclear Energy Statistics 2026.” Axis Intelligence Research, July 2026, axis-intelligence.com/nuclear-energy-statistics/.
Chicago: Axis Intelligence Research and Aidan Jad. “Nuclear Energy Statistics 2026.” Axis Intelligence Research, July 2026. https://axis-intelligence.com/nuclear-energy-statistics/.
FAQ
How many nuclear reactors are operating in the world in 2026?
As of July 2026, 440 nuclear reactors are operable in 31 countries, with a combined installed capacity of approximately 403,265 MWe, according to the World Nuclear Association’s data table updated July 20, 2026, drawing on IAEA PRIS. A further 79 reactors (86,728 MWe) are under construction.
How much electricity does nuclear produce globally?
In 2025, nuclear reactors worldwide generated 2,698 TWh of electricity — a new all-time record — representing approximately 9% of global electricity supply, according to the World Nuclear Association (July 2026). This surpassed the previous record of 2,667 TWh set in 2024 and 2,601 TWh in 2023.
What country generates the most nuclear electricity?
The United States is the world’s largest nuclear electricity producer, generating 785.6 TWh in 2025 from 94 reactors — about 29% of global nuclear output, per World Nuclear Association data. The U.S. nuclear fleet also leads in efficiency, with a 92% capacity factor in 2024 (EIA, August 2025).
What percentage of France’s electricity comes from nuclear?
France generated 68.1% of its national electricity from nuclear energy in 2025, the highest nuclear dependency of any major nation, from 57 reactors producing 373.5 TWh. France has maintained nuclear electricity shares above 60% since the late 1980s, according to World Nuclear Association.
What is a nuclear reactor capacity factor and why does it matter?
A capacity factor measures how much electricity a power plant actually generates compared to its theoretical maximum. The global nuclear fleet averaged 83% in 2024 — the highest of any electricity generation technology (World Nuclear Association Performance Report 2025). A high capacity factor means nuclear plants are generating near their maximum output year-round, unlike solar (20–30%) or wind (25–45%), which generate only when conditions allow.
How does nuclear energy compare to natural gas in CO₂ emissions?
On a full lifecycle basis, nuclear energy emits approximately 5–12 gCO₂e/kWh (IPCC median: 12 gCO₂e/kWh), compared to 400–490 gCO₂e/kWh for natural gas combined-cycle. That means nuclear emits roughly 40 times less CO₂ per unit of electricity than natural gas, according to World Nuclear Association analysis of IPCC and UNECE data.
How many countries have signed the pledge to triple nuclear energy by 2050?
33 countries have endorsed the Declaration to Triple Nuclear Energy by 2050, including the United States, France, Japan, the United Kingdom, Canada, the UAE, and South Korea. The declaration was first launched at COP28 in December 2023, with six additional countries joining at COP29 (November 2024) and two more (Rwanda and Senegal) at COP30 (November 2025), per IAEA reporting.
What is a Small Modular Reactor (SMR) and when will they be deployed at scale?
A Small Modular Reactor (SMR) is a nuclear reactor with electrical output typically below 300 MW, designed for factory manufacture and modular deployment. China’s Linglong One (125 MWe) became the world’s first commercial onshore SMR to enter commercial operation in H1 2026. Canada has issued a construction license for the BWRX-300 design. The IEA identifies 25 GW of global SMR plans, with commercial deployment at scale expected in the 2030s. The IAEA’s high-case scenario projects SMRs accounting for 24% of all new nuclear capacity added by 2050.
What is the Axis Nuclear Energy Index (ANEI™)?
The Axis Nuclear Energy Index™ (ANEI™) is a proprietary composite metric developed by Axis Intelligence Research to rank major nuclear nations across four dimensions: fleet capacity factor (30% weight), share of global nuclear output (25%), reactor construction momentum (25%), and nuclear’s share of national electricity (20%). China leads the 2026 ranking (score: 67.5) due to its unmatched construction growth, followed by the USA (60.2) and France (56.7). The full methodology and all inputs are published under CC BY 4.0 at axis-intelligence.com/nuclear-energy-statistics/.
Internal Links
- Nuclear Energy for Data Centers — how hyperscalers are contracting for nuclear power, including SMR offtake agreements
- AI Data Center Energy Consumption Statistics — the demand side driving nuclear interest from tech companies
- AI Data Center Statistics — broader data center power and capacity trends
- AI Data Center Water Usage Statistics — nuclear’s water footprint compared to fossil fuel alternatives
- Broadband Statistics — infrastructure context for energy-intensive connectivity expansion
- Solar Energy Statistics