Final Magnox reactor at Wylfa shuts down

WYLFA Reactor One, the last generating Magnox nuclear reactor in the world, finally closed down on 30 December 2015 after 44 years of operations.

The Wylfa power station, on Anglesey, Wales, UK, began generating electricity in 1971. At the time, its two reactors had a combined output of 1,000 MW, making it the world’s most powerful nuclear power station. Reactor Two shut down three years ago.

Production of Magnox fuel ceased in 2008 and Wylfa was originally scheduled to shut down in 2010. However, a further five years of operation became possible after regulators approved a process to transfer partly-used fuel between nuclear reactors, known as inter-reactor fuel transfer, or IRX. Over the course of its lifetime, Wylfa generated 232 TWh of electricity. Staff at the site gathered on 30 December to watch the final switch-off procedure.

“Today marks a safe and dignified end to the generation of electricity at Wylfa, and indeed for Magnox, and I am proud to say that I was a part of it,” said site director Stuart Law.

The site has now entered a defuelling phase. Fuel rods from Reactor Two are already being transferred to Sellafield for reprocessing, while the removal of fuel rods from Reactor One is expected to begin in a few months’ time. All fuel is expected to have been removed from the site by the end of 2018, before it is decommissioned.

Generation may yet begin again at Wylfa. Horizon Nuclear Power, a subsidiary of Hitachi, is planning a new 2,700 MW power station on land adjacent to the Magnox plant. Wylfa Newydd will have two advanced boiling water reactors (ABWRs) and Horizon says it is on track to begin generating electricity in the early 2020s.

The closure of Wylfa Reactor One marks the end of an era for Magnox, which began 59 years ago in 1956 when Her Majesty Queen Elizabeth II opened the first Magnox plant, Calder Hall, which had a generating capacity of 190 MW. It was the first industrial-scale power station to be connected to the grid and eventually closed in 2003.