China's nuclear energy program has reached a significant milestone with the achievement of first criticality at the Changjiang Unit 3 reactor. This development marks a crucial step towards the operation of the Hualong One reactor, a Chinese-designed Generation III pressurized water reactor. The Hualong One, also known as the HPR1000, is a key component of China's strategy to accelerate domestic nuclear construction and expand its exports to international markets.
First criticality is a technical achievement where a reactor can sustain a controlled nuclear fission chain reaction without an external neutron source. While it doesn't immediately generate electricity, it is a crucial milestone before the reactor can be synchronized with the power grid. Engineers will now conduct low-power physics tests, gradually increase reactor output, and verify safety systems before grid connection and commercial operation.
The Changjiang Unit 3 is the first of two Hualong One reactors being built during the second phase of the Changjiang Nuclear Power Plant. Construction began in 2021, and the reactors are expected to be fully operational in early 2027, representing a significant investment of around US$5.9 billion. The Hualong One reactor is designed to generate 1.1 gigawatts of electricity, enough to power millions of homes while significantly reducing carbon dioxide emissions compared to coal-fired generation.
The Changjiang site is becoming one of China's most diverse nuclear energy hubs. It already operates two CNP-600 pressurized water reactors, and it is also home to the Linglong One (ACP100) small modular reactor, which is designed for various applications beyond electricity generation, including district heating, industrial steam production, and seawater desalination. The combination of conventional large reactors and advanced SMRs makes Changjiang a strategically important nuclear energy hub.
The Changjiang Nuclear Power Plant plays a central role in Hainan's long-term energy strategy. The province aims to reduce its reliance on fossil fuels while supporting economic growth and rising electricity demand. The successful startup of Unit 3 reflects China's broader nuclear expansion program, with the country commissioning new reactors at a rapid pace. Standardized Hualong One units are the backbone of many new nuclear projects under construction, and as Changjiang Unit 3 progresses through commissioning, it moves closer to joining China's growing fleet of commercial nuclear reactors.
This achievement is a testament to China's commitment to nuclear energy and its potential to contribute to a low-carbon future. As China continues to expand its nuclear program, it will play a crucial role in the global transition to cleaner energy sources.
