National Grid: 'We plan for a range of scenarios'

National Grid has warned that its capacity to supply electricity this winter will be at a seven-year low due to generator closures and breakdowns.

Spare electricity capacity, which ran at about 5% over the winter months last year, would be nearer 4% this year, National Grid said.

Cordi O'Hara, Director of Market Operations at National Grid, told the BBC that contingency plans were in place but she would not speculate on a "worst case scenario".