THE first nuclear reactor built for a British power station in more than 30 years has been completed and is ready to be sent to Hinkley Point C in Somerset.

The reactor pressure vessel is the high-strength steel cylinder that contains nuclear fuel and the chain reaction needed to make heat.

The heat is used to create high-pressure steam to power the world's largest turbines. Teams have spent 80,000 engineering hours on its construction.

There will be two reactor pressure vessels at Hinkley Point C, which will each help power around three million British homes.

Bridgwater Mercury: The reactor is 13 metres long and weighs 500 tonnes.The reactor is 13 metres long and weighs 500 tonnes. (Image: EDF)

Each reactor is 13 metres long and weigh around 500 tonnes. They have been designed to run continuously for 18 months at a time between refuelling.

The reactor has been built by Framatome in France – the same company that built Britain's last nuclear reactor at Sizewell B in 1991.

Since it went into operation in 1995, that reactor has provided 247 TWH (terawatt hours) of electricity, which is enough to power every home in Britain for two-and-a-half years.

A spokesperson for EDF, which is building Hinkley Point C, said: “The centre of the reactor will have an average temperature of around 300°C and can withstand five times more pressure than a submarine at normal operating depths.

“The building that will house the reactor is also taking shape in Somerset.

“On Monday morning, Big Carl, the world’s largest crane, lifted the final 11.6-metre prefabricated steel ring into place on Unit One, which now stands 44m tall.

“The completion of the first reactor pressure vessel marks a major milestone in the construction of Hinkley Point C.

“Together, the two nuclear reactors will offset 600 million tonnes of carbon dioxide emissions over its 60-year lifetime, driving Britain towards net zero and stronger energy security.”

Hinkley Point C will be the UK's first new nuclear power station in more than 20 years. Unit One is due to start generating electricity in June 2027.