Hot testing of second Taipingling unit completed

Friday, 1 August 2025

Tests that simulate the temperatures and pressures which the reactor systems will be subjected to during normal operation have been completed at unit 2 of the Taipingling nuclear power plant. The unit is the second of six HPR1000 (Hualong One) units planned at the site in China’s Guangdong province.

Hot testing of second Taipingling unit completed — (Image: CGN)

“On 30 July, with the drainage of the primary circuit of Unit 2 of the Taipingling nuclear power plant to the circuit water level and the successful completion of the last test of Phase II.3, it marked the successful completion of the hot performance test, and the unit took another step towards the goal of high-quality commissioning,” China General Nuclear (CGN) said.

Hot functional tests involve increasing the temperature of the reactor coolant system and carrying out comprehensive tests to ensure that coolant circuits and safety systems are operating as they should. Carried out before the loading of nuclear fuel, such testing simulates the thermal working conditions of the power plant and verifies that nuclear island and conventional equipment and systems meet design requirements.

Cold functional tests – which are conducted to confirm whether components and systems important to safety are properly installed and ready to operate in a cold condition – were completed at Taipingling 2 earlier this year. The main purpose of those tests – which marked the first time the reactor systems were operated together with the auxiliary systems – was to verify the leak-tightness of the primary circuit.

_{Taipingling units 1 and 2 (Image: CGN)}

The Taipingling plant will eventually have six Hualong One reactors. The construction of the first and second units began in 2019 and 2020, respectively. Hot testing of unit 1 was completed in September 2024. Unit 1 is scheduled to start up in 2025, with unit 2 following in 2026.

Construction of the second phase of the plant – units 3 and 4 – was approved by China’s State Council on 29 December 2023, with construction of unit 3 getting under way in June this year.