John Pettigrew said households could have their gas switched off between 4-7pm in January and February in the “worst case scenario”.

Speaking at the Financial Times’s Energy Transition Summit, Pettigrew said rolling power cuts may need to be imposed if generators fail to secure enough gas from Europe to meet demand.

In National Grid’s “base case” scenario, there would be enough gas and power to meet demand.

But he said: “In the context of the terrible things that are going on in the Ukraine and the consequences of that [it was] right that we set out what some of the potential risks could be”.

A particularly cold snap in January and February 2023 could cause problems for Britain’s gas-fired power stations – the “backbone of the system”.

While Britain doesn’t rely on Russian exports, gas and electricity can be imported from the continent during severe weather events, such as the ‘Beast from the East’ back in 2018.

The situation “would become particularly acute” if wind speeds were too slow to power turbines and electricity from subsea cables were restricted, Pettigrew cautioned.

The comments come after National Grid announced a scheme with energy providers which will see households paid for using electrical appliances out of peak times, to reduce the risk of energy shortages if the crisis was escalated.

Meanwhile, energy regulator Ofgem has also urged households to save on energy where possible, amid fears of potential power cuts this winter.

Energy Price Guarantee cut back

The CEO Jonathan Brearley said a public information campaign will be launched to highlight ways to save energy, as well as what support is available to billpayers and what they can expect from their suppliers.

Just yesterday, the new Chancellor Jeremy Hunt confirmed the government’s landmark Energy Price Guarantee is to be reviewed after just six months rather than the original two year period – a bitter blow to millions of households whose bills were somewhat cushioned from soaring energy bills.

The scaled back and “less generous” approach from April 2023 is likely to offer more targeted help to low-income households rather than a universal support scheme.

At the time, it was announced by Prime Minister Liz Truss, the guarantee set average energy bills at £2,500, savings households £1,000 off the expected £3,549 average bill from 1 October 2022.