China General Nuclear (CGN) said on 30 July that unit 1 of Taishan NPP in Guangdong province - the world's first operating EPR reactor -- had been taken offline to replace damaged fuel rods. An increase in radiation levels had been detected in the primary circuit at the unit on 14 June, but was within the parameters for safe operations. The increase was caused by damage to the cladding in a small number of fuel rods, which is normal during the production, transportation and loading of fuel, China's Ministry of Ecology & Environment (MEE) noted. It estimated that around five of more than 60,000 fuel rods in the Taishan 1 reactor core had been damaged, amounting to less than 0.01% of the total, far below the maximum design level of 0.25%.
CGN said units 1 and 2 at the Taishan plant “have maintained safe and stable operation since they were put into operation. All operating indicators have met the requirements of nuclear safety regulations and power plant technical specifications, and nuclear safety and environmental safety are guaranteed”.
It added that, “at present, a small amount of fuel damage has occurred during the operation of unit 1, but it is still within the allowable range of technical specifications, and the unit can continue to operate stably”. It added: “Considering that unit 1 is the world’s first EPR reactor that has just been put into operation” it would be closed in the interests of safety “after full communication between Chinese and French technical personnel.”
Construction of Taishan 1 began in 2009, followed by unit 2 in 2010. The 1750-megawatt EPRs entered commercial operation in December 2018 and September 2019. The plant is owned by Taishan Nuclear Power Joint Venture Company Limited (TNPJVC) - a joint venture between CGN (51%), French utility EDF (30%) and the Chinese utility Guangdong Energy Group (19%).
EDF subsequently confirmed that, according to the data available, the radiochemical parameters of the primary circuit water remained below the regulatory thresholds in force at the Taishan plant, thresholds which are consistent with international practices. However, on the basis of the analyses, EDF said its operating procedures for the French nuclear fleet would have led EDF, in France, to shut down the reactor in order to accurately assess the situation in progress and stop its development. In Taishan, the corresponding decisions are the responsibility of TNPJVC.
CGN said: “Taishan Nuclear Power Plant insists on safety first and conservative decision-making in accordance with nuclear safety regulations and nuclear power plant operating procedures.” It would therefore carry out maintenance, find the cause of fuel damage, and replace the damaged fuel. “Combined with the start of construction of the power grid to avoid the demand for construction lines of the switch station in western Guangdong, we chose this time to shut down for maintenance.” The company added that, in accordance with the requirements of nuclear safety regulations, it had “always implemented the safety first policy to ensure the safety of nuclear power.”