Sizewell B nuclear power station is being switched off for planned refuelling and maintenance work this week – after a run of 485 days of continuous electricity production.
An extra 1,200 specialist workers will join the nuclear power station's 800 workers for the work, which will include refuelling the reactor along with 14,000 maintenance tasks.
Significant pieces of work being carried out include replacing the rotor on turbine generator 2.
The incredibly powerful turbines spin 3,000 times a minute to power each of the two generators at the station, which provides enough electricity for around 2.5m homes.
A number of Suffolk and Norfolk firms are benefitting from the maintenance with among those receiving contracts being HW Webb Engineering, of Bungay, supplying components; CLS Global Solutions, of Great Yarmouth, providing pipework fabrication; Tecflo, of Great Yarmouth, providing pipework and fittings; and SSCS, of Great Yarmouth, supplying lifting equipment.
Sizewell B is worth £40m to the local economy.
Paul Morton, Sizewell B station director, said: "The start of refuelling brings an end to 485 days of uninterrupted low carbon power supply generated by the station. That's a great achievement only made possible by teamwork at the station and investment by the company.
"With the climate change crisis at the top of the agenda, Sizewell B's workers can be proud of the contribution they are making to a future without polluting fossil fuels."
The turbines will be turned off one at a time - the first was shut down on Wednesday and the next is switched off today.
Preparation work for the outage begins at least two years ahead of refuelling the reactor as part of a 10 year strategic outage plan for the station.
The station is brought offline every 18 months for this work to take place.
A third of the fuel is replaced in the reactor and thousands of maintenance jobs are completed during the seven week period.
Alongside renewables and other nuclear stations, Sizewell B's reliable supply will play an increasingly important role in helping the UK reach net-zero emissions as unabated fossil fuels like coal and gas are retired from power production.
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