Hualong-1: World’s largest nuclear reactor base nears fueling after hot test
The completion of the hot functional testing paves the way for fuel loading and eventual grid connection.
The second unit of the Zhangzhou nuclear power plant in China has hit an important milestone after completing a hot functional test, thus clearing the way for the next steps toward fuel loading and joining the state grid.
Hot functional testing is a process that involves raising the temperature of the reactor’s coolant system and conducting a series of checks to ensure all safety and cooling systems are functioning properly.
Performed before nuclear fuel is loaded, the test simulates the plant’s thermal operating conditions and confirms that both nuclear and conventional systems meet design standards.
The current test comes just months after the Fujian Province-based plant made headlines when its first unit began operation on January 1, 2025, more than five years after construction first began.
Getting ready for commercial launch
The Hualong-1 reactor represents a key breakthrough in third-generation nuclear technology and highlights China’s significant progress in developing advanced, homegrown energy solutions to meet its growing power needs.
Owned by CNNC-Guodian Zhangzhou Energy Company—a joint venture between CNNC (51 percent) and China Guodian Corporation (49 percent)—the reactor is an indigenous, three-loop pressurized water design that combines features from CNNC’’’s ACP1000 and CGN’s ACPR1000+ models.