COVID-19 impacts and restrictions are expected to delay the U.K.’s $30.8 billion Hinkley Point C nuclear power plant project by six months and add another $680 million to the most recent cost estimate. Since work started on the twin-unit, 3,200-MW plant in 2016, the cost hike is now nearly 28%.

“This is the first time we have adjusted our schedule since the project commenced construction,” Stuart Crooks, managing director of project owner-developer Hinkley Point C Ltd., said in a video broadcast. The company is led by French state-controlled energy firm EdF Group.

When the pandemic reached the U.K. early last year, the company postponed some work to create safe working spaces while mobilizing extra resources to catch up lost time, said Crooks. But “10 months on and it’s clear that the pandemic is still in full force [eating] away at our opportunity to recover lost time from 2020,” he added.

The number of U.K. deaths since the pandemic started was officially reported at nearly 104,000 on Jan. 27. The UK’s per capita death rate is now the world’s worst, according to John Hopkins University statistics, and the daily toll is still high.

Having lost three months last year, Hinkley managers estimate that the project is forecast to lose another three this year, “assuming that conditions allow us to ramp back up the resources" by early April,” added Crooks.

When the project secured government approval in 2016, its cost was put at $24.6 billion. In September 2019, EdF raised that estimate to around $30 billion, at 2015 prices, lifting it now to about $30.7 billion.

Despite the pandemic, the project has met 18 of 20 milestones so far, and “the last two are not far behind,” said Crooks. The company now aims to place the first reactor dome at the end of 2022.