Flagship project has seen cost and schedule overruns, but is now close to operation.

The loading of fuel into the reactor vessel of the Flamanville-3 EPR nuclear power plant in northern France has been completed, Alain Morvan, director of the Flamanville-3 project, said in a post on LinkedIn.

Morvan said 241 fuel assemblies were loaded. Each was about five metres high and weighed nearly 800 kg.

The handling of the fuel assemblies was carried out by teams from state nuclear operator EDF. Workers from nuclear company Framatome were responsible for monitoring the reactor core and a team from France-based industrial company Reel oversaw the functioning of equipment used for these operations.

EDF announced on 8 May that it started fuel loading, a day after French nuclear regulator ASN gave permission for the fuel loading and startup procedures to begin.

The loading of the reactor concludes the first stage of startup, Morvan said.

“Flamanville-3 becomes the 57th reactor in the French nuclear fleet, Moravon said in his LinkedIn post. “This is the culmination of many years of work nourished by an ‘unusual’ collective energy, allowing us to begin startup operations.”

He said 150,000 pieces of equipment and all the EPR’s circuits have been rigorously checked and conditioned. More than 58,000 operating criteria were tested.

Further operational tests will now be carried out with the 1.630-MW plant’s power gradually increased until it is connected to the grid, scheduled for this summer, at 25% power.

Completion Initially Scheduled For 2012

The construction of Flamanville-3 started in 2007 and the reactor had been initially expected to be completed in 2012.

The unit is currently 12 years overdue and the expected final construction costs of the unit have already risen from an initial estimate of €3.3 billion ($3.56 billion) to over €13.2 billion.

Multiple factors have contributed to the delays and cost overruns at Flamanville-3, but a French report into the project in 2019 noted that several elements of the project’s construction had been launched prior to the completion of the reactor’s design, leading to certain sections of the work having to be demolished and rebuilt.

ASN said on 7 May that after fuel loading, it will continue to monitor Flamanville-3’s operations during the pre-critical phase, before a nuclear chain reaction begins in the unit’s core.

This monitoring will look primarily at whether the safety circuits are operating correctly. The regulator will subsequently have to approve the start of nuclear fission and the staged increase in operational power to 25% and then 80% of the unit’s total capacity.

There are three EPR units in commercial operation globally – two are at the Taishan nuclear station in China and one at the Olkiluoto nuclear station in Finland. Additionally, there are two units under construction at Hinkley Point C in the UK’s southwestern county of Somerset.