Storm Arwen, five years on: four lessons for a winter power cut

Storm Arwen arrived at the end of November 2021, and nearly a million homes in Britain lost power. Most were back within a day: Ofgem found that 82% of customers had their power restored within 24 hours. But nearly 4,000 homes in parts of England and Scotland were off for more than a week, at the time of year when it's dark by four. A small number lost their phone signal as well, so they couldn't report the fault or make calls, according to the review the government commissioned from the industry's Energy Emergencies Executive Committee. Ofgem concluded that thousands of customers had an unacceptable service, and the network companies paid out £44 million.

Reading both reviews five years on, I'd pull four lessons out of them for a family at home in winter.

1. Ring 105

If your power goes off, call 105. It's free across England, Scotland and Wales, and it puts you through to the company that runs the electricity network in your area. That's the company that can fix a fault on the network; the supplier who sends your bill can't. Write 105 on the sheet by the door, because the website you'd normally check may not load.

2. Keep one room warm, safely

The UK's Chief Medical Officers published advice in December 2025 on keeping warm in a power cut. Wear several thin layers. Gather everyone in one room to share the warmth, close the curtains when it gets dark, and put a towel or sheet along the bottom of the doors. Shut the windows and doors of rooms you're not using, and look out for neighbours, friends and family who may be struggling.

The same advice carries a warning I'd underline. Don't use camping stoves or barbecues indoors, because of the risk of carbon monoxide poisoning, which can kill. A generator belongs outdoors, at least 6 metres from the building with the exhaust facing away from windows and doors, which in most flats means not having one at all. The NHS recommends a carbon monoxide alarm that makes a loud sound, one for each room with an appliance that burns gas, oil, coal or wood. If you haven't got one, I'd buy it before anything else on this page.

3. Torches, not candles

Many people reach for a candle first. A torch or a head torch gives better light, and it can't set the curtains alight when a tired adult nods off on the sofa. The Prophet ﷺ told us not to leave a fire burning in our houses when we go to sleep (Sahih al-Bukhari 6293). It's still the best fire-safety advice I know, and it applies to heaters as well.

4. Practise once

Pick an evening this winter, switch the main lights off at Maghrib and spend two hours as if the power had gone, then pray Isha by head torch. You'll soon find out whether there's a torch for everyone, and whether anyone knows where the spare batteries are kept.

The part with no easy answer

Layers and one warm room will get most families through a night or two. I don't think they get a frail grandparent through a week in a cold flat, and I haven't seen official advice that claims they do. If someone at home would struggle, sign them up for the Priority Services Register now. Ofgem says that in an emergency, network operators can offer people on the register priority support, which can include alternative heating and cooking. I've written more about the register in Your neighbour is part of your plan. Then agree in advance where they would go to stay warm if a cut ran past a couple of days.

Storm Arwen was five years ago this month.