China's Taipingling unit 2 achieves first nuclear chain reaction milestone

Taipingling unit 2 has achieved its first sustained nuclear chain reaction. The milestone marks a key step for the reactor before it connects to the power grid. China General Nuclear (CGN) confirmed the event as a foundation for future operations. The 1,116 MWe pressurised water reactor reached first criticality at 00:22 on 25 June. A day earlier, at 09:45 local time, the first criticality control point was officially signed and released. This followed the completion of the first nuclear fuel loading on 3 May, which involved 177 fuel assemblies.

On 30 April, China’s National Nuclear Safety Administration (NNSA) had issued a 40-year operating licence for the unit. Taipingling 2 is the second of six planned Hualong One (HPR1000) reactors at the Guangdong site. The entire plant, with a total investment of over CNY120 billion (USD17 billion), will eventually generate more than 55 billion kilowatt-hours annually.

CGN stated that first criticality supports the next stages of grid connection and commissioning. Once fully operational, the six reactors will cut standard coal use by about 16.65 million tonnes yearly. They will also reduce carbon dioxide emissions by around 50.82 million tonnes annually. Taipingling 2 now moves closer to full operation after achieving criticality. The reactor’s progress aligns with China’s expansion of its Hualong One fleet. The plant’s future output will significantly boost power generation while lowering emissions.