CONSTRUCTION of the Hinkley Point C nuclear power station is speeding up as lessons learned from building its first reactor are applied to the second one.

This week, the second reactor building was due to have its 245-tonne domed roof lifted in place by ‘Big Carl’, the world’s largest crane.

It will be a major construction milestone for the UK’s first new nuclear power station in 30 years, as it was for EDF-owned Hinkley C’s first reactor building in December, 2023.

The dome closes the second reactor building to allow the installation of its nuclear reactor and equipment.

Unit two is being built 20 to 30 per cent faster than the first reactor building, thanks to the experience gained so far and innovation which includes more modularisation and prefabrication.

The advantages of repeating an identical design with such innovations will also benefit Sizewell C, in Suffolk, which has recently been approved by the Government as the UK’s next nuclear build.

An EDF spokesperson said: “Experience and innovation helps us to build the second identical unit faster.

“We are transforming the way we build, with prefabrication in civil construction now approaching 60 per cent.

“More factories on and off site means ever larger pieces are being lifted into place, with big productivity gains, turning Hinkley Point C into Britain’s first large modular reactor.

“Previously, the intricate steel reinforcement used to strengthen concrete was fixed together in situ, sometimes at height, in confined spaces or exposed to the weather.

“Now, we are using ‘Big Carl’ to lift in giant prefabricated sections called ‘mega-cages’.

“They are built in prefabrication yards or at our new purpose-built factory in Bristol Port.

“The approach reduces congestion on site, improves safety, quality, and productivity.

“Sections built in Bristol arrive by sea, cutting installation time by 75 per cent and manufacturing time by 20 per cent.

“Productivity is boosted as factory workers do not spend time travelling to site or staying away from home.”

The spokesperson said a good example of modular construction was the manufacturing of steel and concrete pools which hold water for safe refuelling of the reactors.

They said EDF had been using learnings from its nuclear plant in Flamanville, France, so the pools for Hinkley C were prefabricated in weatherproof bunkers on site to improve quality and reduce schedule risk.

The largest ‘reactor cavity’ pool weighs more than 700 tonnes and sits on top of the reactor.

Hinkley C’s unit two pool was manufactured in nearly half the time of the one for the first reactor with more work carried out in the bunker before installation and a new welding technique allowing completion four times faster than on unit one.

The two identical Hinkley C nuclear reactors will provide reliable low carbon power and meet about 10 per cent of Britain’s current electricity consumption.

The station currently has 12,000 people working on site every day, which is due to reach 15,000 at peak construction, with another 26,000 right across Britain helping to build the project.