The Chooz B nuclear power plant located in Chooz, France, has two pressurised water reactors (PWR) with a combined net capacity of 3GW.

Owned and operated by EDF, the Chooz nuclear energy generating site earlier housed the 305MW Chooz A reactor unit which ceased operation in 1991 and is currently being decommissioned.

The Chooz B1 and Chooz B2 reactor units of 1.5MW capacity each were first grid-connected in August 1996 and April 1997 respectively, while both the units commenced commercial operations in 2000.

The Chooz B nuclear power plant produced 17.9 billion kilowatt-hours of electricity in 2019 accounting for approximately 4.7% of the total nuclear power produced in France and approximately 42% of the total power consumption in the Grand-Est region of France.

However, both of the Chooz B reactor units were shut down in the second half of August 2020 due to the drop in the water flow rate of the Meuse River which serves as the source of water for the plant operation.

Location and site details

The Chooz nuclear power station is located on a 200ha-site on the banks of the Meuse River in Chooz, in the Ardennes department in northern France, near the France-Belgium border.

Chooz B nuclear power plant make-up

The Chooz B nuclear power plant comprises two generating units with each unit comprising a 1,500MW pressurised water reactor along with steam generators and Arabelle steam turbines. The construction of the two units was started in 1985 and 1986, respectively.

The Chooz B2 NPP had undergone a ten-year outage for 144 days in 2019. The reactor was shut down in March 2019 and was reconnected to the grid in August 2019.

Similarly, the Chooz B1 was subjected to a ten-year outage in 2020. The reactor was shut down in February 2020 and was reconnected to the grid in August 2020.

As part of the post-Fukushima measures being implemented at the Chooz NPP, two ultimate-backup diesel generators (DUS) were commissioned in 2019, while the construction of an emergency control center is scheduled for 2024.

The Chooz A reactor decommissioning

The Chooz A pressurised water reactor (PWR) started operations in April 1967 and was permanently shut down in October 1991. The capacity of the reactor was initially 242MW, which was gradually increased to 305MW.

It will be the first pressurised water reactor to be decommissioned in France. The reactor is located in a cavern and the fuel removal from the reactor was carried out in 1995.

The initial decommissioning operations following the shutdown included emptying the circuits and evacuating fuel.

The dismantling of peripheral buildings including the machine room, the pumping station was completed in 2004.

The work on dismantling the reactor vessel was started in 2016 and is expected to be completed in 2022.

Contracts awarded

Mammoet was contracted to decommission, lift, and transport of four steam generators, weighing approximately 120t each, located in the reactor building of Chooz A power plant. The contract was executed during 2011 and 2012.

A Westinghouse Electric Company-led consortium was contracted to provide reactor vessel dismantling services for the Chooz A power plant in April 2010.

The scope of the contract includes overall project management, reactor vessel internals segmentation, the reactor nozzle cutting, and the dismantling of the reactor vessel thermal insulation.