The United States Has the Most Nuclear Capacity, 96.8 GW in 2024

Ember's latest complete year of installed capacity data is 2024. Among the 27 countries with at least 1.00 GW of nuclear capacity in 2024, the United States has the most, 96.8 GW, and China added the most since 2019, +12.1 GW. Romania ran its nuclear plants at the highest capacity factor, 95.5%. Worldwide, nuclear capacity was 407 GW in 2024, against 404 GW in 2019.

Key Facts

The latest complete Ember year of installed capacity data is 2024; each country is compared with its own 2019 and 2014 figures.
World nuclear capacity was 407 GW in 2024, 404 GW in 2019 and 385 GW in 2014.
World nuclear generation was 2,777 TWh in 2024, a capacity factor of 77.6% on 407 GW.
the United States has the most nuclear capacity: 96.8 GW in 2024, generating 782 TWh.
Over 2019 to 2024, China added the most nuclear capacity: +12.1 GW, to 60.8 GW.
Over 2014 to 2024, China added the most nuclear capacity: +40.8 GW, to 60.8 GW.
Pakistan grew fastest in percentage terms since 2019 among countries that already had 1.00 GW or more: +218%.
Capacity factor in 2024 ranged from 29.2% in Japan to 95.5% in Romania, across 27 countries with a usable figure.

Countries With the Most Nuclear Capacity, 2024

Ember, 2009 to 2024

Installed capacity, 2024

Installed nuclear capacity in 2024, GW
United States	96.8 GW
France	61.4 GW
China	60.8 GW
Japan	33.1 GW
Russia	28.7 GW
South Korea	26.1 GW
Canada	12.7 GW
India	8.18 GW
Spain	7.12 GW
Sweden	7.00 GW

Highest capacity factor, 2024

Highest nuclear capacity factor in 2024, percent
Romania	95.5%
Switzerland	92.1%
United States	91.9%
Belgium	90.5%
Brazil	90.3%
Hungary	89.8%
Bulgaria	89.4%
Spain	87.2%
Mexico	87.0%
Russia	85.7%

Installed nuclear capacity in GW for the five countries with the most in 2024, 2009 to 2024. United States ends at 96.8 GW; France ends at 61.4 GW; China ends at 60.8 GW; Japan ends at 33.1 GW; Russia ends at 28.7 GW.

Annual statistics, 2009 to 2024

Installed nuclear capacity, five largest countries
Year	United States	France	China	Japan	Russia
2009	101 GW	63.1 GW	9.08 GW	48.9 GW	24.3 GW
2010	101 GW	63.1 GW	10.8 GW	49.0 GW	24.3 GW
2011	101 GW	63.1 GW	12.6 GW	49.0 GW	24.3 GW
2012	102 GW	63.1 GW	12.6 GW	46.2 GW	25.3 GW
2013	99.2 GW	63.1 GW	14.7 GW	44.3 GW	25.3 GW
2014	98.6 GW	63.1 GW	20.1 GW	44.3 GW	26.4 GW
2015	98.7 GW	63.1 GW	27.2 GW	42.1 GW	27.2 GW
2016	99.6 GW	63.1 GW	33.6 GW	41.5 GW	28.0 GW
2017	99.6 GW	63.1 GW	35.8 GW	39.1 GW	28.0 GW
2018	99.4 GW	63.1 GW	44.7 GW	38.0 GW	29.2 GW
2019	98.1 GW	63.1 GW	48.7 GW	33.1 GW	30.4 GW
2020	96.5 GW	61.4 GW	49.9 GW	33.1 GW	29.5 GW
2021	95.6 GW	61.4 GW	53.3 GW	33.1 GW	29.7 GW
2022	94.7 GW	61.4 GW	55.5 GW	33.1 GW	29.7 GW
2023	95.7 GW	61.4 GW	56.9 GW	33.1 GW	29.7 GW
2024	96.8 GW	61.4 GW	60.8 GW	33.1 GW	28.7 GW

Nuclear Capacity, Growth and Capacity Factor by Country, 2024

27 countries

Installed nuclear capacity by country in 2024, change since 2019 and 2014, generation and capacity factor. Column headings sort the table.
Country	Capacity 2024	Change since 2019	Growth since 2019	Change since 2014	Growth since 2014	Generation 2024	Capacity factor 2024
United States	96.8 GW	-1.29 GW	-1%	-1.74 GW	-2%	782 TWh	91.9%
France	61.4 GW	-1.73 GW	-3%	-1.73 GW	-3%	380 TWh	70.5%
China	60.8 GW	+12.1 GW	+25%	+40.8 GW	+203%	451 TWh	84.4%
Japan	33.1 GW	0 GW	0%	-11.2 GW	-25%	84.9 TWh	29.2%
Russia	28.7 GW	-1.70 GW	-6%	+2.27 GW	+9%	216 TWh	85.7%
South Korea	26.1 GW	+2.80 GW	+12%	+5.33 GW	+26%	189 TWh	82.5%
Canada	12.7 GW	-670 MW	-5%	-1.36 GW	-10%	85.5 TWh	76.8%
India	8.18 GW	+1.40 GW	+21%	+2.40 GW	+42%	54.7 TWh	76.1%
Spain	7.12 GW	0 GW	0%	-280 MW	-4%	54.5 TWh	87.2%
Sweden	7.00 GW	-1.62 GW	-19%	-2.51 GW	-26%	50.7 TWh	82.4%
United Kingdom	5.88 GW	-3.38 GW	-37%	-4.06 GW	-41%	40.6 TWh	78.6%
United Arab Emirates	5.56 GW	+5.56 GW	n/a	+5.56 GW	n/a	40.6 TWh	83.2%
Finland	4.37 GW	+1.58 GW	+57%	+1.62 GW	+59%	32.6 TWh	84.9%
Czechia	4.29 GW	0 GW	0%	0 GW	0%	29.7 TWh	78.8%
Belgium	3.93 GW	-2.00 GW	-34%	-2.00 GW	-34%	31.3 TWh	90.5%
Pakistan	3.62 GW	+2.48 GW	+218%	+2.83 GW	+358%	23.2 TWh	72.9%
Switzerland	2.97 GW	-360 MW	-11%	-340 MW	-10%	24.0 TWh	92.1%
Slovakia	2.47 GW	+530 MW	+27%	+530 MW	+27%	18.2 TWh	84.0%
Belarus	2.34 GW	+2.34 GW	n/a	+2.34 GW	n/a	15.7 TWh	76.3%
Hungary	2.03 GW	+20 MW	+1%	+30 MW	+1%	16.0 TWh	89.8%
Bulgaria	2.01 GW	0 GW	0%	+30 MW	+2%	15.8 TWh	89.4%
Brazil	1.99 GW	0 GW	0%	0 GW	0%	15.8 TWh	90.3%
South Africa	1.93 GW	-10 MW	-1%	-10 MW	-1%	7.80 TWh	46.0%
Argentina	1.75 GW	0 GW	0%	+230 MW	+15%	10.5 TWh	68.0%
Mexico	1.61 GW	0 GW	0%	0 GW	0%	12.3 TWh	87.0%
Romania	1.30 GW	0 GW	0%	0 GW	0%	10.9 TWh	95.5%
Iran	1.02 GW	0 GW	0%	0 GW	0%	7.04 TWh	78.6%

Countries with at least 1.00 GW of nuclear capacity in 2024: 27 are listed, and 5 countries with less are left out. Each is compared with its own 2019 and 2014 values; a country that has not published 2024 is not listed, and a blank means Ember has no figure. Growth in percent is shown only when the earlier year had at least 100 MW; a tiny base gives meaningless percentages.

How Capacity Factor Is Calculated

2024, 8,784 hours

Capacity factor is a country's nuclear generation in 2024 divided by its installed capacity times the 8,784 hours in 2024, using the same year for both. It is the share of the year the fleet would have needed to run at full output to produce what it did. Guards: the factor is left blank where capacity is missing or under 1.00 GW, where generation is missing, and where it comes out above 100% (none here), which is treated as a data error or under reported capacity. If capacity grew during 2024, the factor is understated, because a full year of output is set against the larger figure.

Lowest capacity factor, 2024

Lowest nuclear capacity factor in 2024, percent
Japan	29.2%
South Africa	46.0%
Argentina	68.0%
France	70.5%
Pakistan	72.9%
India	76.1%
Belarus	76.3%
Canada	76.8%
Iran	78.6%
United Kingdom	78.6%

Source: Ember (ember-energy.org), licensed under CC BY 4.0. Data as of 2024. Installed capacity and generation from Ember annual statistics, complete years to 2024.