The United States did not bring its first commercial nuclear reactor of the twenty-first century online until 2016, according to reporting published by Nature. That installation was Unit 2 of the Watts Bar Nuclear Plant in Tennessee, which began commercial operation two decades after Unit 1 entered service at the same site.
Nature published the assessment on August 26, 2026, as part of a peer-reviewed supplement titled Nature Outlook: Nuclear power. Reactor company Oklo Inc. provided financial support for the supplement, though Nature stated that the publication maintained full independence in all editorial decisions related to the content.
Private companies and research institutions are focusing on new reactor designs and alternative energy systems. In the fusion sector, 46 companies are competing to commercialize fusion systems for power generation, with a growing cohort of startup firms betting on the technology. Engineers are also examining whether compact nuclear reactors can operate on the road as mobile power units.
Scientists are also addressing fuel disposal hurdles and public safety debates surrounding nuclear policy. The publication describes nuclear byproducts as historically among the best-managed industrial waste. Beyond terrestrial storage, researchers are developing techniques to use nuclear waste to power space missions as developers pitch advanced nuclear solutions for clean-energy demands.
