Nuclear power delivered roughly 10% of the world’s electricity in 2023 from 392.5 GW(e) of installed capacity. That output comes from grids running at unusually high reliability, with US reactors averaging a 92.7% capacity factor in 2022. The rest of the story depends on what changed next, from new capacity additions to reactor retirements.
Key Takeaways
- In 2023, the global installed nuclear power capacity stood at 392.5 gigawatts electric (GW(e)), providing about 10% of the world's electricity.
- Overnight capital cost for nuclear is $6,445-$12,392 per kW.
- Nuclear fuel cycle emits 12 gCO2/kWh lifecycle.
- Chernobyl accident released 5.2 EBq of radioactivity in 1986.
- World plans 62 GW new nuclear by 2030.
Nuclear energy supplies a large share of reliable electricity worldwide, helping keep emissions lower.
Related reading
01 · Category
Capacity and Generation30 stats
01
In 2023, the global installed nuclear power capacity stood at 392.5 gigawatts electric (GW(e)), providing about 10% of the world's electricity.
02
The United States had 94 operating nuclear reactors with a total net capacity of 96.2 GW(e) as of 2023.
03
France generated 379.5 TWh from nuclear power in 2022, representing 69.7% of its total electricity production.
04
China commissioned 5.6 GW of new nuclear capacity in 2023, bringing its total to 57.1 GW(e).
05
Nuclear power plants operated at an average capacity factor of 92.7% in the US in 2022, the highest among energy sources.
06
Globally, 413 nuclear reactors were operable in 31 countries as of mid-2024.
07
South Korea's nuclear plants generated 162.5 TWh in 2022, accounting for 32.5% of its electricity.
08
The UAE's Barakah plant reached full operation with 5.6 GW capacity by 2024.
09
Russia's nuclear fleet produced 215.9 TWh in 2022, 20.1% of its electricity.
10
India had 23 operating reactors with 7.48 GW capacity at end-2023.
11
Ukraine's nuclear plants generated 127.5 TWh in 2022 despite conflict, 55% of electricity.
12
Canada's CANDU reactors had 13.5 GW capacity, generating 92.8 TWh in 2022.
13
Global nuclear generation avoided 2.5 billion tonnes of CO2 emissions in 2023.
14
Japan's restarted reactors generated 69 TWh in 2023, up from 2022.
15
Sweden's nuclear output was 69.8 TWh in 2022, 40% of electricity.
16
Belgium's seven reactors produced 43.6 TWh in 2022, 40.7% of power.
17
Switzerland generated 28.2 TWh nuclear in 2022, 38.5% of total.
18
Slovakia's four reactors generated 29.3 TWh in 2022, 53.5% share.
19
Hungary's Paks plant produced 15.1 TWh in 2022, 48.7% of electricity.
20
Bulgaria's Kozloduy reactors generated 15.3 TWh in 2022, 36.4%.
21
Armenia's Metsamor reactor produced 2.4 TWh in 2022, 25.3% share.
22
Global nuclear capacity under construction was 61.4 GW(e) in 2024.
23
54 reactors were under construction worldwide as of 2024.
24
Pakistan's nuclear plants generated 17.3 TWh in 2022, 9.6% of electricity.
25
Czech Republic's Dukovany and Temelin produced 27.9 TWh in 2022, 35.3%.
26
Finland's Olkiluoto 3 (1.6 GW) started commercial operation in 2023.
27
US nuclear generation was 775 TWh in 2023, 18.6% of electricity.
28
UK's nuclear output fell to 58.2 TWh in 2022 due to plant closures.
29
Iran's Bushehr plant generated 8.1 TWh in 2022, 2.2% share.
30
Global lifetime capacity factor for nuclear is over 80% historically.
Interpretation
Capacity and Generation Interpretation
Despite accounting for just 10% of global electricity, the world's 413 nuclear reactors are the low-drama workhorses of the grid, powering everything from French baguettes to South Korean semiconductors while quietly dodging billions of tonnes of CO2 with near-constant reliability.
02 · Category
Costs and Economics24 stats
01
Overnight capital cost for nuclear is $6,445-$12,392 per kW.
02
Levelized cost of nuclear electricity (LCOE) is $141-221/MWh in 2023.
03
Vogtle Units 3&4 cost $34.1 billion total for 2.2 GW.
04
French EPR Flamanville 3 cost €19.7 billion overrun to €12.7 billion.
05
Operating cost for US nuclear is $33.2/MWh, lowest among baseload.
06
Lifetime LCOE for existing US nuclear fleet is $36.06/MWh.
07
Hinkley Point C UK EPRs budgeted at £31-36 billion for 3.2 GW.
08
Fuel cost is 0.5-1% of nuclear electricity price vs 70% for gas.
09
Decommissioning costs for US nuclear: $500 million-$1 billion per reactor.
10
Waste management cost included in US nuclear electricity at 0.1¢/kWh.
11
Capacity factor drives nuclear economics: 93% vs solar 24%.
12
South Korea's APR-1400 built at $2,500/kW.
13
China's Hualong One reactors cost $2,800-$3,500/kW.
14
UAE Barakah plants cost $24.4 billion for 5.6 GW, $4,357/kW.
15
Nuclear R&D investment globally $2.5 billion/year vs renewables $20B.
16
Long-term fuel contracts stabilize nuclear costs vs volatile gas.
17
Plant life extension from 40 to 60-80 years saves $billions.
18
EU nuclear LCOE €55-101/MWh vs offshore wind €100-200.
19
Finland Olkiluoto 3 cost €11.5 billion for 1.6 GW.
20
Savings from nuclear: $3.7 trillion in US since 1973.
21
Jobs: 475,000 supported by US nuclear industry.
22
Tax credits under IRA boost nuclear competitiveness.
23
SMRs projected at $3,000-$5,000/kW by 2030.
24
Nuclear provides 9% of global electricity at <5% investment share.
Interpretation
Costs and Economics Interpretation
Nuclear power's economic story is one of extreme contrasts, where staggering upfront costs and infamous overruns are offset by decades of remarkably cheap, stable, and reliable electricity once the plant is finally running.
03 · Category
Environmental Effects26 stats
01
Nuclear fuel cycle emits 12 gCO2/kWh lifecycle.
02
Nuclear avoids 64 gCO2/kWh vs gas combined cycle.
03
Land use for nuclear: 0.3 m² per MWh vs solar 5.7 m².
04
Global nuclear fleet displaces 2.5 GtCO2 annually.
05
Uranium mining impact low: 0.001-0.01 deaths/TWh.
06
Nuclear water use: 2.3 L/MWh vs coal 1,900 L/MWh.
07
No SOx/NOx/PM emissions from nuclear operations.
08
High-level waste: 2g per person/year in France.
09
Spent fuel volume: 250 tonnes/GW-year vs ash 300,000t from coal.
10
Recycling reuses 96% of spent fuel material.
11
Deep geological repositories planned for 100,000+ year isolation.
12
Nuclear mining footprint smaller than rare earths for renewables.
13
Biodiversity in nuclear exclusion zones higher than nearby.
14
Lifecycle GHG: nuclear 40 gCO2eq/kWh median IPCC.
15
Avoided air pollution deaths: 1.8 million globally 1971-2009.
16
Thermal pollution minimal: nuclear 0.5-1°C rise vs hydro 5-10°C.
17
Enriched uranium uses seawater desalination compatible.
18
Breeder reactors could extend fuel for 30,000 years.
19
Thorium cycle potential reduces long-lived waste.
20
SMRs reduce land use further to 0.1 m²/MWh.
21
Nuclear supports EV growth without grid emissions rise.
22
Finland's final repository construction started 2024.
23
US Yucca Mountain designed for 70,000 tonnes waste.
24
Global spent fuel inventory: ~400,000 tonnes as of 2023.
25
Fusion projected to have near-zero long-term waste.
26
IAEA: Nuclear life cycle impacts comparable to wind/solar.
Interpretation
Environmental Effects Interpretation
Nuclear energy, while far from perfect, presents itself as the pragmatic, high-density workhorse of the clean energy stable: it squats efficiently on a postage stamp of land, sipping water while displacing a mountain of carbon and air pollution, all while confining its stubborn but surprisingly scant waste to a long-term, geological lockbox rather than our atmosphere.
More related reading
04 · Category
Safety and Accidents26 stats
01
Chernobyl accident released 5.2 EBq of radioactivity in 1986.
02
Fukushima Daiichi released about 0.015 EBq of Cs-137 in 2011.
03
No immediate deaths from radiation at Fukushima; 2,313 from evacuation stress.
04
Chernobyl caused 31 acute radiation syndrome deaths initially.
05
Lifetime cancer deaths from Chernobyl estimated at 4,000-9,000 by UN.
06
Three Mile Island released 0.00002 EBq, no health effects detected.
07
Global nuclear death rate is 0.03 per TWh, vs 24.6 for coal.
08
IAEA reports zero fatal accidents at new reactors post-1970s.
09
Over 18,500 reactor-years of operation worldwide with excellent safety record.
10
French nuclear fleet averaged 0.6 significant events per reactor-year.
11
US NRC rates all US reactors at safety level 1 (lowest risk).
12
Radiation exposure from nuclear power is 0.0002 mSv/person/year globally.
13
Coal power causes 24.6 deaths/TWh from air pollution, nuclear 0.03.
14
Wind causes 0.04 deaths/TWh, solar 0.02, nuclear safer than both.
15
Kyshtym disaster (1957) rated level 6 on INES scale.
16
SL-1 accident (1961) killed 3 workers, only US fatal reactor incident.
17
Windscale fire (1957) released 0.07 EBq iodine-131, no deaths.
18
Nuclear plants have core damage frequency <1 in 10,000 reactor-years.
19
Post-Fukushima safety upgrades cost $160 billion globally.
20
No public radiation deaths from commercial nuclear operations ever.
21
Chernobyl exclusion zone wildlife thrives, no long-term ecological damage.
22
Fukushima wastewater release monitored, tritium levels below limits.
23
Gen IV reactors designed for meltdown-proof passive safety.
24
US nuclear plants prevented 764 coal plant-equivalent deaths yearly.
25
Radiation from one chest CT scan equals lifetime nuclear plant dose.
26
INES level 7 accidents: only Chernobyl and Fukushima.
Interpretation
Safety and Accidents Interpretation
Despite the sensationalized ghost stories of nuclear accidents, the data reveals an industry that, statistically speaking, has saved hundreds of thousands of lives by quietly displacing far more lethal fossil fuels, proving that the greatest risks often lie not in the technology itself but in our disproportionate fear of it.
05 · Category
Technological Developments26 stats
01
World plans 62 GW new nuclear by 2030.
02
30 countries operating reactors, 32 with plants under construction/planned.
03
SMRs: 80+ designs, NuScale VOYGR certified by US NRC.
04
Gen IV forum: 6 reactor types, sodium-cooled fast breeders lead.
05
China's CFR-600 fast reactor (600 MW) grid-connected 2023.
06
Russia's BN-800 operational, MOX fuel breeder.
07
Accident-tolerant fuels tested in US HALDEN reactor.
08
High-assay low-enriched uranium (HALEU) for advanced reactors.
09
Molten salt reactors: Kairos Power raised $300M 2024.
10
Microreactors: Oklo Aurora 1.5 MW for remote power.
11
Floating nuclear plants: Russia's Akademik Lomonosov operational.
12
Lead-cooled fast reactors: Europe's ALFRED demo planned.
13
Gas-cooled reactors: UK's HTR-PM equivalent advances.
14
ITER fusion tokamak 500 MW thermal target 2025.
15
Private fusion: Commonwealth Fusion Systems SPARC 2025.
16
Small modular reactors construction starts: NuScale Romania 2028.
17
Thorium molten salt: China's TMSR-LF1 critical 2023.
18
Digital twins for reactor monitoring: Westinghouse AP1000.
19
Long-life cores: 20-year fuel cycle developments.
20
Pyroprocessing for fast reactor fuel recycling.
21
India's PFBR 500 MW fast breeder fuel loading 2024.
22
High-temperature gas reactors for hydrogen production.
23
Medical isotopes: 80% from research reactors.
24
Space reactors: NASA's KRUSTY tested 2018.
25
Advanced manufacturing: 3D printing reactor components.
26
IAEA PRIS: 430 reactors planned worldwide.
Interpretation
Technological Developments Interpretation
While the world is cautiously building a new generation of sophisticated, accident-resistant nuclear reactors, from miniature microreactors to colossal fusion projects, the real race is on to see whether this atomic renaissance can outpace both our climate deadlines and its own complex legacy.
Reference
Cite This Report
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APA
Megan Gallagher. (2026, February 13). Nuclear Energy Statistics. Gitnux. https://gitnux.org/nuclear-energy-statistics
MLA
Megan Gallagher. "Nuclear Energy Statistics." Gitnux, 13 Feb 2026, https://gitnux.org/nuclear-energy-statistics.
Chicago
Megan Gallagher. 2026. "Nuclear Energy Statistics." Gitnux. https://gitnux.org/nuclear-energy-statistics.
Sources & references
30 datasets cited across this report · attribution is report-level