Linglong One completes cold functional testing ahead of hot commissioning phase

China National Nuclear Corporation/Linglong One (ACP100)

The Linglong One ACP100 small modular reactor at Changjiang in Hainan completed cold functional testing on October 16, 2025, verifying that all major plant systems can operate safely under no-load conditions. The test confirmed that instrumentation, controls and conventional island systems meet design specifications before transitioning to hot testing with the reactor operating at full thermal power.

• Cold functional tests validate systems without generating heat, reducing risk before nuclear fuel loading.
• Test verified primary circuit, secondary circuit, safety systems and auxiliary equipment operate as designed.
• Completion clears the way for hot functional testing and eventual fuel loading in 2026 or later.
• CNNC targets commercial operation in 2027 after criticality and grid-connection milestones.