Cranes surround a reactor under construction at Hinkley Point C, in Bridgwater, on Sept. 27.

Electricite de France SA is holding talks with investors over funding for the Hinkley Point C nuclear power plant under construction in the UK, as the French utility grapples with the ballooning cost of the project.

EDF is seeking to raise as much as £4 billion ($5.2 billion) through a bespoke financial instrument which would give investors a stake in the Hinkley project, people familiar with the matter said asking not to be named because the discussions are private. Investors would be reimbursed if the construction isn’t completed, one of the people said.

The cost of building the two reactors Hinkley is expected to reach £47.9 billion in current terms, due in part to lingering labor shortages and supply chain issues. EDF’s bill for the project has also increased after China General Nuclear Power Corp., its partner in the Somerset project, stopped funding its minority share of project at the end of 2023, having fulfilled its contractual commitment. The costs and the long timescales for nuclear projects make it difficult to attract investors.

EDF is engaged in talks with sovereign wealth funds and large infrastructure funds, the people said, while declining to name potential investors.

Centrica Plc, is one of the companies considering investing in Hinkley, according to different people familiar with the matter who also requested not to be named. The utility is a shareholder in the UK’s existing nuclear fleet and is in talks with the UK government on financing Sizewell C, a follow on nuclear project from Hinkley.

Discussions are still at an early stage and could fall through as the completion of Hinkley Point C remains years away, one of the people said.

Representatives for EDF and Centrica declined to comment.

The first reactor at Hinkley Point C is scheduled to become operational in 2030 — five years later than initially planned — under EDF’s base-case scenario. The modeling flags that risks will probably materialize during the remaining construction years.

Funding requirements at home are also huge for EDF. The French state-owned utility is boosting spending to prolong the life of its aging atomic power stations and it faces a soaring bill to build new reactors.

The French utility has had “contact” with potential investors who might join the Hinkley project, EDF Chief Executive Officer Luc Remont said in an earnings call at the end of July.

EDF’s long-delayed Flamanville-3 in France is due to be connected to the grid by the end of the year. Potential investors in Hinkley will be watching closely for signs of further problems.

Hinkley Point C will benefit from a guaranteed power price for 35 years if the plant is completed by Nov. 1, 2036. Both the UK and EDF say the station is a key plank to Britain’s net zero ambitions.