Wedoany.com Report-Dec.17, Xudabao Nuclear Power Plant's unit 3 has successfully completed cold functional testing, allowing transition from installation to the commissioning stage.

China National Nuclear Corporation (CNNC) announced the achievement on December 12, 2025, for the collaborative project involving Chinese and Russian expertise.

It said: "The cold functional test is a significant milestone in the construction of a nuclear power unit, representing the first comprehensive 'check-up' of the reactor and primary loop equipment. It aims to verify the overall performance of related systems and equipment under cold, high-pressure conditions. The successful completion of this test fully demonstrates that the primary loop pressure boundary of unit 3 at the Xudabao Nuclear Power Plant is intact and the equipment performance is reliable, effectively ensuring the safe and stable operation of the unit in the future."

Agreements signed in June 2018 between Russia and China covered the construction of two VVER-1200 reactors at the Xudabao site. Further contracts in June 2019 included the general construction terms for units 3 and 4, along with nuclear fuel supply arrangements.

Work on unit 3 commenced in July 2021, followed by unit 4 in May 2022. The reactor building dome for unit 3 was positioned in July 2023. The units are planned to begin operations in 2027 and 2028, respectively.

The Xudabao facility is owned by Liaoning Nuclear Power Company Limited, a partnership comprising CNNC with 70 percent interest, Datang International Power Generation Company with 20 percent, and State Development and Investment Corporation with 10 percent.

Cold functional testing involves pressurizing systems without nuclear fuel to confirm integrity of the primary circuit and associated components under operational-like conditions.

This verification step ensures equipment reliability before hot testing and fuel loading phases.

Successful outcomes provide assurance for subsequent commissioning activities, including system alignments and performance validations.

The VVER-1200 design incorporates advanced safety features and efficient generation capabilities suitable for large-scale electricity production.

Joint international cooperation facilitates technology transfer and project execution, drawing on established expertise in reactor construction.

Site progress reflects coordinated efforts across engineering, procurement, and installation disciplines.

Ownership structure combines state-affiliated entities with specialized roles in energy development.

The plant contributes to expanding nuclear capacity, supporting stable baseload power supply in the region.

Commissioning timelines align with phased preparations, allowing thorough testing at each stage.

Unit 3's milestone advances the overall schedule, paving the way for unit 4's parallel activities.

Ongoing construction maintains focus on quality and safety standards throughout implementation.

The project's advancement underscores commitment to reliable energy infrastructure development.

By meeting key technical checkpoints, Xudabao unit 3 positions itself for timely integration into the grid upon final approvals.

These developments enhance contributions from nuclear sources to national electricity needs.