The United States holds the largest share of global nuclear generating capacity, part of a group of five countries that together account for 71 percent of the world total, according to Energy Information Administration data. That concentration highlights how a handful of national fleets, led by the US, dominate worldwide nuclear output.

Domestically, nuclear plays a central role. Nuclear generation accounted for about 19 percent of US electricity in 2024, making it one of the largest single sources on the grid and the largest source of carbon-free generation. The US fleet's steady output has held that share consistent even as wind and solar capacity expanded.

The data also frames the scale of the current buildout ambitions. Moving US capacity from roughly 100 gigawatts toward the 400 gigawatt target set for 2050 would require sustained construction, restarts, and life extensions over the coming decades. The existing fleet provides the foundation for that growth.

Rising electricity demand gives the figures added weight. As AI and data center load push national consumption to record highs, planners are looking to nuclear's reliable capacity to help meet demand that renewables alone cannot cover on a continuous basis. The EIA data positions the US as the anchor of the global nuclear sector heading through 2026.

Source: U.S. Energy Information Administration - https://www.eia.gov/todayinenergy/detail.php?id=65904