Britain's grid operator says the lights will stay on this winter despite the Iran war but warns of 'tight days'

An independent investigation found NESO engineers had 'high levels of stress and concern' about keeping supply up given the gap between renewable and gas-fired power. The operator still forecasts a 5.9GW surplus from 31 October to 31 March. The pinch points are most likely in December or January, on cold, still days. Deborah Petterson, NESO's resilience director, insists households 'can be confident'.

Last winter's safety buffer stood at 10%, slightly above this year's margin.

National Gas expects more gas burned at peak demand because renewables are 'intermittent'.

Europe faces winter with below-normal gas storage after the Iran war squeezed supplies.