Defence Secretary Philip Hammond

The UK Royal Navy will refuel the nuclear reactor of the first Vanguard-class nuclear-powered submarine, HMS Vanguard, the UK defence secretary Philip Hammond has announced.

Philip Hammond said that the HMS Vanguard nuclear reactor will be refuelled during its planned deep maintenance period, which begins in late 2015 and will last for around three-and-a-half years; therefore it is expected that there will be no impact on deterrent operations.

The decision follows the detection of low levels of radioactivity in a prototype core that has been running since 2002 at the Naval Reactor Test Establishment at Dounreay in Scotland.

"The safety of the UK’s naval nuclear reactor at the test establishment at Dounreay and on our submarines is of critical importance to us, as is the maintenance of continuous at-sea deterrence," said Hammond.

"That is why I have taken the decision to apply the precautionary principle, even though there is no evidence at this stage that the problem detected with the test reactor is likely to present in the operational reactors."

Designed to help assess how the reactor cores within submarines will perform over time, the prototype has been run for significantly longer periods and at higher intensity to enable the UK Ministry of Defence (MoD) to detect potential age- or use-related issues that may arise later among the operational reactor cores.

"The additional cost of refuelling Vanguard is estimated to be around £120m over the next six years," added Hammond.

Nuclear reactor refuelling will allow the submarine to operate effectively and safely until the planned fleet of Successor submarines enter service from 2028.

Image: UK defence secretary Philip Hammond. Photo: © Crown copyright.

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