China Rapidly Expands Large Nuclear Reactor Fleet

China is rapidly expanding its nuclear power infrastructure, focusing on large-scale reactors to meet growing electricity demand. The country has nearly doubled its nuclear fleet since 2016, achieving a total power capacity of almost 60 gigawatts. The majority of these new facilities are gigawatt-scale pressurized-water reactors.

Construction activity in China highlights this rapid pace. Six new reactors began construction in 2025, followed by two more in the first five months of 2026. This expansion puts China on track to exceed the installed nuclear capacity of both the United States and the European Union by 2030. The average construction time for a new reactor in China was between five and seven years as of 2024, significantly shorter than the global average of approximately nine years and the 15 years taken for the two most recent US reactors. China attributes this speed in part to a standardized project management system for design and construction.

In contrast, nuclear development in the United States has been slower, with only two reactors (Unit 3 and Unit 4 at Plant Vogtle in Georgia) built since 2016. The US currently holds the world's largest nuclear fleet, with France ranking second, relying on nuclear power for about two-thirds of its electricity. However, France connected its latest reactor to the grid in December 2024, its first in over two decades.

The construction of large nuclear projects presents substantial challenges, including multi-billion dollar upfront investments and decades-long payback periods. Complex designs and regulatory changes can also lead to increased costs and extended timelines.

In response, there is considerable interest and investment in smaller reactors, particularly in the United States. The concept behind smaller reactors is to reduce initial investment and potentially allow for factory-based construction, which could lower overall costs. The US Department of Energy (DOE) launched a pilot program with a goal for three test reactors to reach criticality by July 4, 2026. California-based Antares recently achieved this milestone with its Mark-0 reactor. Antares plans to develop microreactors capable of producing between 100 kilowatts and 1 megawatt of electricity, significantly smaller than current grid-scale reactors. While the Mark-0 currently lacks power conversion and heat removal systems, the company aims to produce electricity by late 2027 and deploy reactors in the field by 2028. Private sector investment, including from major technology companies, is also directed towards new reactor designs to power data centers.

(Source: MIT Technology Review)