Britain’s first commercial nuclear reactors, at Calder Hall, Windscale, began operating in 1956, and over the next 15 years, a further 10 Magnox nuclear power stations were opened around the country at Berkeley, Bradwell, Chapelcross, Dungeness, Hinckley Point, Hunterston, Oldbury, Sizewell, Trawsfynydd and Wylva.
To fuel these power stations, rods of natural uranium clad in magnesium alloy were used, hence the name Magnox, but after spending several years inside a reactor core, these rods would become increasingly clogged with contaminants, reducing their heat output.
However, as the rods still contained about 96% reusable, uranium it was decided to send this ‘spent fuel’ to the United Kingdom Atomic Energy Authority’s Windscale Works at Sellafield on the Cumbrian Coast for reprocessing, and in 1963, British Rail introduced its first purpose-built nuclear flask…