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National Grid highlights potential for power shortages this winter

Network brings forward scheme to cope with potential electricity supply issues at nuclear, gas, coal and oil power stations


National Grid has called on electricity suppliers to declare how much spare capacity they could muster to cover peak times either side of Christmas – highlighting the possibility of power shortages this winter.

The power network is officially bringing forward by a year a scheme to tap additional capacity to cope with closures of nuclear, gas, coal and oil power stations and unexpected plant repairs.

The prospect of power shortages is likely to alarm ministers, who are concerned that an already depleted system could be exposed by a small number of temporary shutdowns at crucial plants.

Britain is already facing a power capacity crunch as ageing and polluting stations are shutting down, while new plants are slow to start operating because of a government overhaul of energy policy.

National Grid said it was extending its search for additional sources of temporary supplies to keep the lights on and support heavy industries that use large amounts of electricity. It is looking for additional supplies for the two months before and after Christmas.

"At this stage we don't know if these reserve services will be needed, but they could provide an additional safeguard," said Cordi O'Hara, National Grid's director of UK market operations.

The grid cited emergency shutdowns at two UK nuclear power stations operated by French firm EDF and fires at a large coal-powered plant and and another fuelled by biomass.

National Grid formally launched a tender for its Supplemental Balancing Reserve on Tuesday, asking power generators how much spare capacity they could provide to fill a potential supply gap.

The fires were at E.ON's biomass-fuelled Ironbridge plant in Shropshire and SSE's Ferrybridge plant in Yorkshire, forcing them to reduce output; while a power plant in Barking, east London is to close and there have been production problems at EDF Energy's Heysham and Hartlepool nuclear power stations.

If the network operator decides SBR is necessary this winter, it will launch a competitive tender for a specific amount of spare capacity. Power generators would have to be available to provide additional electricity between 7am and 9pm from November to February.

The new back-up capacity mechanism is in parallel with a programme that allows National Grid to ask contracted users – mostly factories – to reduce electricity demand when the system is strained.

• This article was amended on 5 September 2014. An earlier version suggested that the Ironbridge power station was coal-powered.