GITNUXREPORT 2026

Nuclear Energy Statistics

Nuclear energy reliably provides ten percent of the world's electricity with minimal emissions.

Rajesh Patel

Rajesh Patel

Team Lead & Senior Researcher with over 15 years of experience in market research and data analytics.

First published: Feb 13, 2026

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Key Statistics

Statistic 1

In 2023, the global installed nuclear power capacity stood at 392.5 gigawatts electric (GW(e)), providing about 10% of the world's electricity.

Statistic 2

The United States had 94 operating nuclear reactors with a total net capacity of 96.2 GW(e) as of 2023.

Statistic 3

France generated 379.5 TWh from nuclear power in 2022, representing 69.7% of its total electricity production.

Statistic 4

China commissioned 5.6 GW of new nuclear capacity in 2023, bringing its total to 57.1 GW(e).

Statistic 5

Nuclear power plants operated at an average capacity factor of 92.7% in the US in 2022, the highest among energy sources.

Statistic 6

Globally, 413 nuclear reactors were operable in 31 countries as of mid-2024.

Statistic 7

South Korea's nuclear plants generated 162.5 TWh in 2022, accounting for 32.5% of its electricity.

Statistic 8

The UAE's Barakah plant reached full operation with 5.6 GW capacity by 2024.

Statistic 9

Russia's nuclear fleet produced 215.9 TWh in 2022, 20.1% of its electricity.

Statistic 10

India had 23 operating reactors with 7.48 GW capacity at end-2023.

Statistic 11

Ukraine's nuclear plants generated 127.5 TWh in 2022 despite conflict, 55% of electricity.

Statistic 12

Canada's CANDU reactors had 13.5 GW capacity, generating 92.8 TWh in 2022.

Statistic 13

Global nuclear generation avoided 2.5 billion tonnes of CO2 emissions in 2023.

Statistic 14

Japan's restarted reactors generated 69 TWh in 2023, up from 2022.

Statistic 15

Sweden's nuclear output was 69.8 TWh in 2022, 40% of electricity.

Statistic 16

Belgium's seven reactors produced 43.6 TWh in 2022, 40.7% of power.

Statistic 17

Switzerland generated 28.2 TWh nuclear in 2022, 38.5% of total.

Statistic 18

Slovakia's four reactors generated 29.3 TWh in 2022, 53.5% share.

Statistic 19

Hungary's Paks plant produced 15.1 TWh in 2022, 48.7% of electricity.

Statistic 20

Bulgaria's Kozloduy reactors generated 15.3 TWh in 2022, 36.4%.

Statistic 21

Armenia's Metsamor reactor produced 2.4 TWh in 2022, 25.3% share.

Statistic 22

Global nuclear capacity under construction was 61.4 GW(e) in 2024.

Statistic 23

54 reactors were under construction worldwide as of 2024.

Statistic 24

Pakistan's nuclear plants generated 17.3 TWh in 2022, 9.6% of electricity.

Statistic 25

Czech Republic's Dukovany and Temelin produced 27.9 TWh in 2022, 35.3%.

Statistic 26

Finland's Olkiluoto 3 (1.6 GW) started commercial operation in 2023.

Statistic 27

US nuclear generation was 775 TWh in 2023, 18.6% of electricity.

Statistic 28

UK's nuclear output fell to 58.2 TWh in 2022 due to plant closures.

Statistic 29

Iran's Bushehr plant generated 8.1 TWh in 2022, 2.2% share.

Statistic 30

Global lifetime capacity factor for nuclear is over 80% historically.

Statistic 31

Overnight capital cost for nuclear is $6,445-$12,392 per kW.

Statistic 32

Levelized cost of nuclear electricity (LCOE) is $141-221/MWh in 2023.

Statistic 33

Vogtle Units 3&4 cost $34.1 billion total for 2.2 GW.

Statistic 34

French EPR Flamanville 3 cost €19.7 billion overrun to €12.7 billion.

Statistic 35

Operating cost for US nuclear is $33.2/MWh, lowest among baseload.

Statistic 36

Lifetime LCOE for existing US nuclear fleet is $36.06/MWh.

Statistic 37

Hinkley Point C UK EPRs budgeted at £31-36 billion for 3.2 GW.

Statistic 38

Fuel cost is 0.5-1% of nuclear electricity price vs 70% for gas.

Statistic 39

Decommissioning costs for US nuclear: $500 million-$1 billion per reactor.

Statistic 40

Waste management cost included in US nuclear electricity at 0.1¢/kWh.

Statistic 41

Capacity factor drives nuclear economics: 93% vs solar 24%.

Statistic 42

South Korea's APR-1400 built at $2,500/kW.

Statistic 43

China's Hualong One reactors cost $2,800-$3,500/kW.

Statistic 44

UAE Barakah plants cost $24.4 billion for 5.6 GW, $4,357/kW.

Statistic 45

Nuclear R&D investment globally $2.5 billion/year vs renewables $20B.

Statistic 46

Long-term fuel contracts stabilize nuclear costs vs volatile gas.

Statistic 47

Plant life extension from 40 to 60-80 years saves $billions.

Statistic 48

EU nuclear LCOE €55-101/MWh vs offshore wind €100-200.

Statistic 49

Finland Olkiluoto 3 cost €11.5 billion for 1.6 GW.

Statistic 50

Savings from nuclear: $3.7 trillion in US since 1973.

Statistic 51

Jobs: 475,000 supported by US nuclear industry.

Statistic 52

Tax credits under IRA boost nuclear competitiveness.

Statistic 53

SMRs projected at $3,000-$5,000/kW by 2030.

Statistic 54

Nuclear provides 9% of global electricity at <5% investment share.

Statistic 55

Nuclear fuel cycle emits 12 gCO2/kWh lifecycle.

Statistic 56

Nuclear avoids 64 gCO2/kWh vs gas combined cycle.

Statistic 57

Land use for nuclear: 0.3 m² per MWh vs solar 5.7 m².

Statistic 58

Global nuclear fleet displaces 2.5 GtCO2 annually.

Statistic 59

Uranium mining impact low: 0.001-0.01 deaths/TWh.

Statistic 60

Nuclear water use: 2.3 L/MWh vs coal 1,900 L/MWh.

Statistic 61

No SOx/NOx/PM emissions from nuclear operations.

Statistic 62

High-level waste: 2g per person/year in France.

Statistic 63

Spent fuel volume: 250 tonnes/GW-year vs ash 300,000t from coal.

Statistic 64

Recycling reuses 96% of spent fuel material.

Statistic 65

Deep geological repositories planned for 100,000+ year isolation.

Statistic 66

Nuclear mining footprint smaller than rare earths for renewables.

Statistic 67

Biodiversity in nuclear exclusion zones higher than nearby.

Statistic 68

Lifecycle GHG: nuclear 40 gCO2eq/kWh median IPCC.

Statistic 69

Avoided air pollution deaths: 1.8 million globally 1971-2009.

Statistic 70

Thermal pollution minimal: nuclear 0.5-1°C rise vs hydro 5-10°C.

Statistic 71

Enriched uranium uses seawater desalination compatible.

Statistic 72

Breeder reactors could extend fuel for 30,000 years.

Statistic 73

Thorium cycle potential reduces long-lived waste.

Statistic 74

SMRs reduce land use further to 0.1 m²/MWh.

Statistic 75

Nuclear supports EV growth without grid emissions rise.

Statistic 76

Finland's final repository construction started 2024.

Statistic 77

US Yucca Mountain designed for 70,000 tonnes waste.

Statistic 78

Global spent fuel inventory: ~400,000 tonnes as of 2023.

Statistic 79

Fusion projected to have near-zero long-term waste.

Statistic 80

IAEA: Nuclear life cycle impacts comparable to wind/solar.

Statistic 81

Chernobyl accident released 5.2 EBq of radioactivity in 1986.

Statistic 82

Fukushima Daiichi released about 0.015 EBq of Cs-137 in 2011.

Statistic 83

No immediate deaths from radiation at Fukushima; 2,313 from evacuation stress.

Statistic 84

Chernobyl caused 31 acute radiation syndrome deaths initially.

Statistic 85

Lifetime cancer deaths from Chernobyl estimated at 4,000-9,000 by UN.

Statistic 86

Three Mile Island released 0.00002 EBq, no health effects detected.

Statistic 87

Global nuclear death rate is 0.03 per TWh, vs 24.6 for coal.

Statistic 88

IAEA reports zero fatal accidents at new reactors post-1970s.

Statistic 89

Over 18,500 reactor-years of operation worldwide with excellent safety record.

Statistic 90

French nuclear fleet averaged 0.6 significant events per reactor-year.

Statistic 91

US NRC rates all US reactors at safety level 1 (lowest risk).

Statistic 92

Radiation exposure from nuclear power is 0.0002 mSv/person/year globally.

Statistic 93

Coal power causes 24.6 deaths/TWh from air pollution, nuclear 0.03.

Statistic 94

Wind causes 0.04 deaths/TWh, solar 0.02, nuclear safer than both.

Statistic 95

Kyshtym disaster (1957) rated level 6 on INES scale.

Statistic 96

SL-1 accident (1961) killed 3 workers, only US fatal reactor incident.

Statistic 97

Windscale fire (1957) released 0.07 EBq iodine-131, no deaths.

Statistic 98

Nuclear plants have core damage frequency <1 in 10,000 reactor-years.

Statistic 99

Post-Fukushima safety upgrades cost $160 billion globally.

Statistic 100

No public radiation deaths from commercial nuclear operations ever.

Statistic 101

Chernobyl exclusion zone wildlife thrives, no long-term ecological damage.

Statistic 102

Fukushima wastewater release monitored, tritium levels below limits.

Statistic 103

Gen IV reactors designed for meltdown-proof passive safety.

Statistic 104

US nuclear plants prevented 764 coal plant-equivalent deaths yearly.

Statistic 105

Radiation from one chest CT scan equals lifetime nuclear plant dose.

Statistic 106

INES level 7 accidents: only Chernobyl and Fukushima.

Statistic 107

World plans 62 GW new nuclear by 2030.

Statistic 108

30 countries operating reactors, 32 with plants under construction/planned.

Statistic 109

SMRs: 80+ designs, NuScale VOYGR certified by US NRC.

Statistic 110

Gen IV forum: 6 reactor types, sodium-cooled fast breeders lead.

Statistic 111

China's CFR-600 fast reactor (600 MW) grid-connected 2023.

Statistic 112

Russia's BN-800 operational, MOX fuel breeder.

Statistic 113

Accident-tolerant fuels tested in US HALDEN reactor.

Statistic 114

High-assay low-enriched uranium (HALEU) for advanced reactors.

Statistic 115

Molten salt reactors: Kairos Power raised $300M 2024.

Statistic 116

Microreactors: Oklo Aurora 1.5 MW for remote power.

Statistic 117

Floating nuclear plants: Russia's Akademik Lomonosov operational.

Statistic 118

Lead-cooled fast reactors: Europe's ALFRED demo planned.

Statistic 119

Gas-cooled reactors: UK's HTR-PM equivalent advances.

Statistic 120

ITER fusion tokamak 500 MW thermal target 2025.

Statistic 121

Private fusion: Commonwealth Fusion Systems SPARC 2025.

Statistic 122

Small modular reactors construction starts: NuScale Romania 2028.

Statistic 123

Thorium molten salt: China's TMSR-LF1 critical 2023.

Statistic 124

Digital twins for reactor monitoring: Westinghouse AP1000.

Statistic 125

Long-life cores: 20-year fuel cycle developments.

Statistic 126

Pyroprocessing for fast reactor fuel recycling.

Statistic 127

India's PFBR 500 MW fast breeder fuel loading 2024.

Statistic 128

High-temperature gas reactors for hydrogen production.

Statistic 129

Medical isotopes: 80% from research reactors.

Statistic 130

Space reactors: NASA's KRUSTY tested 2018.

Statistic 131

Advanced manufacturing: 3D printing reactor components.

Statistic 132

IAEA PRIS: 430 reactors planned worldwide.

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Imagine a power source so reliable it works nearly 93% of the time, silently providing one-tenth of the world's electricity and preventing billions of tonnes of carbon emissions annually—this is the often misunderstood reality of nuclear energy today.

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.
  • The United States had 94 operating nuclear reactors with a total net capacity of 96.2 GW(e) as of 2023.
  • France generated 379.5 TWh from nuclear power in 2022, representing 69.7% of its total electricity production.
  • Chernobyl accident released 5.2 EBq of radioactivity in 1986.
  • Fukushima Daiichi released about 0.015 EBq of Cs-137 in 2011.
  • No immediate deaths from radiation at Fukushima; 2,313 from evacuation stress.
  • Overnight capital cost for nuclear is $6,445-$12,392 per kW.
  • Levelized cost of nuclear electricity (LCOE) is $141-221/MWh in 2023.
  • Vogtle Units 3&4 cost $34.1 billion total for 2.2 GW.
  • Nuclear fuel cycle emits 12 gCO2/kWh lifecycle.
  • Nuclear avoids 64 gCO2/kWh vs gas combined cycle.
  • Land use for nuclear: 0.3 m² per MWh vs solar 5.7 m².
  • World plans 62 GW new nuclear by 2030.
  • 30 countries operating reactors, 32 with plants under construction/planned.
  • SMRs: 80+ designs, NuScale VOYGR certified by US NRC.

Nuclear energy reliably provides ten percent of the world's electricity with minimal emissions.

Capacity and Generation

  • In 2023, the global installed nuclear power capacity stood at 392.5 gigawatts electric (GW(e)), providing about 10% of the world's electricity.
  • The United States had 94 operating nuclear reactors with a total net capacity of 96.2 GW(e) as of 2023.
  • France generated 379.5 TWh from nuclear power in 2022, representing 69.7% of its total electricity production.
  • China commissioned 5.6 GW of new nuclear capacity in 2023, bringing its total to 57.1 GW(e).
  • Nuclear power plants operated at an average capacity factor of 92.7% in the US in 2022, the highest among energy sources.
  • Globally, 413 nuclear reactors were operable in 31 countries as of mid-2024.
  • South Korea's nuclear plants generated 162.5 TWh in 2022, accounting for 32.5% of its electricity.
  • The UAE's Barakah plant reached full operation with 5.6 GW capacity by 2024.
  • Russia's nuclear fleet produced 215.9 TWh in 2022, 20.1% of its electricity.
  • India had 23 operating reactors with 7.48 GW capacity at end-2023.
  • Ukraine's nuclear plants generated 127.5 TWh in 2022 despite conflict, 55% of electricity.
  • Canada's CANDU reactors had 13.5 GW capacity, generating 92.8 TWh in 2022.
  • Global nuclear generation avoided 2.5 billion tonnes of CO2 emissions in 2023.
  • Japan's restarted reactors generated 69 TWh in 2023, up from 2022.
  • Sweden's nuclear output was 69.8 TWh in 2022, 40% of electricity.
  • Belgium's seven reactors produced 43.6 TWh in 2022, 40.7% of power.
  • Switzerland generated 28.2 TWh nuclear in 2022, 38.5% of total.
  • Slovakia's four reactors generated 29.3 TWh in 2022, 53.5% share.
  • Hungary's Paks plant produced 15.1 TWh in 2022, 48.7% of electricity.
  • Bulgaria's Kozloduy reactors generated 15.3 TWh in 2022, 36.4%.
  • Armenia's Metsamor reactor produced 2.4 TWh in 2022, 25.3% share.
  • Global nuclear capacity under construction was 61.4 GW(e) in 2024.
  • 54 reactors were under construction worldwide as of 2024.
  • Pakistan's nuclear plants generated 17.3 TWh in 2022, 9.6% of electricity.
  • Czech Republic's Dukovany and Temelin produced 27.9 TWh in 2022, 35.3%.
  • Finland's Olkiluoto 3 (1.6 GW) started commercial operation in 2023.
  • US nuclear generation was 775 TWh in 2023, 18.6% of electricity.
  • UK's nuclear output fell to 58.2 TWh in 2022 due to plant closures.
  • Iran's Bushehr plant generated 8.1 TWh in 2022, 2.2% share.
  • Global lifetime capacity factor for nuclear is over 80% historically.

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.

Costs and Economics

  • Overnight capital cost for nuclear is $6,445-$12,392 per kW.
  • Levelized cost of nuclear electricity (LCOE) is $141-221/MWh in 2023.
  • Vogtle Units 3&4 cost $34.1 billion total for 2.2 GW.
  • French EPR Flamanville 3 cost €19.7 billion overrun to €12.7 billion.
  • Operating cost for US nuclear is $33.2/MWh, lowest among baseload.
  • Lifetime LCOE for existing US nuclear fleet is $36.06/MWh.
  • Hinkley Point C UK EPRs budgeted at £31-36 billion for 3.2 GW.
  • Fuel cost is 0.5-1% of nuclear electricity price vs 70% for gas.
  • Decommissioning costs for US nuclear: $500 million-$1 billion per reactor.
  • Waste management cost included in US nuclear electricity at 0.1¢/kWh.
  • Capacity factor drives nuclear economics: 93% vs solar 24%.
  • South Korea's APR-1400 built at $2,500/kW.
  • China's Hualong One reactors cost $2,800-$3,500/kW.
  • UAE Barakah plants cost $24.4 billion for 5.6 GW, $4,357/kW.
  • Nuclear R&D investment globally $2.5 billion/year vs renewables $20B.
  • Long-term fuel contracts stabilize nuclear costs vs volatile gas.
  • Plant life extension from 40 to 60-80 years saves $billions.
  • EU nuclear LCOE €55-101/MWh vs offshore wind €100-200.
  • Finland Olkiluoto 3 cost €11.5 billion for 1.6 GW.
  • Savings from nuclear: $3.7 trillion in US since 1973.
  • Jobs: 475,000 supported by US nuclear industry.
  • Tax credits under IRA boost nuclear competitiveness.
  • SMRs projected at $3,000-$5,000/kW by 2030.
  • Nuclear provides 9% of global electricity at <5% investment share.

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.

Environmental Effects

  • Nuclear fuel cycle emits 12 gCO2/kWh lifecycle.
  • Nuclear avoids 64 gCO2/kWh vs gas combined cycle.
  • Land use for nuclear: 0.3 m² per MWh vs solar 5.7 m².
  • Global nuclear fleet displaces 2.5 GtCO2 annually.
  • Uranium mining impact low: 0.001-0.01 deaths/TWh.
  • Nuclear water use: 2.3 L/MWh vs coal 1,900 L/MWh.
  • No SOx/NOx/PM emissions from nuclear operations.
  • High-level waste: 2g per person/year in France.
  • Spent fuel volume: 250 tonnes/GW-year vs ash 300,000t from coal.
  • Recycling reuses 96% of spent fuel material.
  • Deep geological repositories planned for 100,000+ year isolation.
  • Nuclear mining footprint smaller than rare earths for renewables.
  • Biodiversity in nuclear exclusion zones higher than nearby.
  • Lifecycle GHG: nuclear 40 gCO2eq/kWh median IPCC.
  • Avoided air pollution deaths: 1.8 million globally 1971-2009.
  • Thermal pollution minimal: nuclear 0.5-1°C rise vs hydro 5-10°C.
  • Enriched uranium uses seawater desalination compatible.
  • Breeder reactors could extend fuel for 30,000 years.
  • Thorium cycle potential reduces long-lived waste.
  • SMRs reduce land use further to 0.1 m²/MWh.
  • Nuclear supports EV growth without grid emissions rise.
  • Finland's final repository construction started 2024.
  • US Yucca Mountain designed for 70,000 tonnes waste.
  • Global spent fuel inventory: ~400,000 tonnes as of 2023.
  • Fusion projected to have near-zero long-term waste.
  • IAEA: Nuclear life cycle impacts comparable to wind/solar.

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.

Safety and Accidents

  • Chernobyl accident released 5.2 EBq of radioactivity in 1986.
  • Fukushima Daiichi released about 0.015 EBq of Cs-137 in 2011.
  • No immediate deaths from radiation at Fukushima; 2,313 from evacuation stress.
  • Chernobyl caused 31 acute radiation syndrome deaths initially.
  • Lifetime cancer deaths from Chernobyl estimated at 4,000-9,000 by UN.
  • Three Mile Island released 0.00002 EBq, no health effects detected.
  • Global nuclear death rate is 0.03 per TWh, vs 24.6 for coal.
  • IAEA reports zero fatal accidents at new reactors post-1970s.
  • Over 18,500 reactor-years of operation worldwide with excellent safety record.
  • French nuclear fleet averaged 0.6 significant events per reactor-year.
  • US NRC rates all US reactors at safety level 1 (lowest risk).
  • Radiation exposure from nuclear power is 0.0002 mSv/person/year globally.
  • Coal power causes 24.6 deaths/TWh from air pollution, nuclear 0.03.
  • Wind causes 0.04 deaths/TWh, solar 0.02, nuclear safer than both.
  • Kyshtym disaster (1957) rated level 6 on INES scale.
  • SL-1 accident (1961) killed 3 workers, only US fatal reactor incident.
  • Windscale fire (1957) released 0.07 EBq iodine-131, no deaths.
  • Nuclear plants have core damage frequency <1 in 10,000 reactor-years.
  • Post-Fukushima safety upgrades cost $160 billion globally.
  • No public radiation deaths from commercial nuclear operations ever.
  • Chernobyl exclusion zone wildlife thrives, no long-term ecological damage.
  • Fukushima wastewater release monitored, tritium levels below limits.
  • Gen IV reactors designed for meltdown-proof passive safety.
  • US nuclear plants prevented 764 coal plant-equivalent deaths yearly.
  • Radiation from one chest CT scan equals lifetime nuclear plant dose.
  • INES level 7 accidents: only Chernobyl and Fukushima.

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.

Technological Developments

  • World plans 62 GW new nuclear by 2030.
  • 30 countries operating reactors, 32 with plants under construction/planned.
  • SMRs: 80+ designs, NuScale VOYGR certified by US NRC.
  • Gen IV forum: 6 reactor types, sodium-cooled fast breeders lead.
  • China's CFR-600 fast reactor (600 MW) grid-connected 2023.
  • Russia's BN-800 operational, MOX fuel breeder.
  • Accident-tolerant fuels tested in US HALDEN reactor.
  • High-assay low-enriched uranium (HALEU) for advanced reactors.
  • Molten salt reactors: Kairos Power raised $300M 2024.
  • Microreactors: Oklo Aurora 1.5 MW for remote power.
  • Floating nuclear plants: Russia's Akademik Lomonosov operational.
  • Lead-cooled fast reactors: Europe's ALFRED demo planned.
  • Gas-cooled reactors: UK's HTR-PM equivalent advances.
  • ITER fusion tokamak 500 MW thermal target 2025.
  • Private fusion: Commonwealth Fusion Systems SPARC 2025.
  • Small modular reactors construction starts: NuScale Romania 2028.
  • Thorium molten salt: China's TMSR-LF1 critical 2023.
  • Digital twins for reactor monitoring: Westinghouse AP1000.
  • Long-life cores: 20-year fuel cycle developments.
  • Pyroprocessing for fast reactor fuel recycling.
  • India's PFBR 500 MW fast breeder fuel loading 2024.
  • High-temperature gas reactors for hydrogen production.
  • Medical isotopes: 80% from research reactors.
  • Space reactors: NASA's KRUSTY tested 2018.
  • Advanced manufacturing: 3D printing reactor components.
  • IAEA PRIS: 430 reactors planned worldwide.

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.