Most power cuts last minutes. A large one, caused by a storm, a cyber-attack or a grid failure, can last days. The Iberian blackout of April 2025 took out power for tens of millions of people in Spain and Portugal within seconds. That is why the EU now asks every household to be able to cope for at least 72 hours.
What stops when the power goes
- Light and heating, including gas boilers, which need electricity to run.
- Card payments and cash machines. Shops that can open will often take cash only.
- Mobile data and internet, once the masts' backup batteries run down, usually within hours.
- Water pressure in some buildings and towns, because pumps need power. No pressure also means no flushing.
- Fridges and freezers. A closed freezer keeps food frozen for about a day.
The essentials
Light
Every guide lists a torch. A head torch leaves your hands free, and one per person avoids arguments in the dark. Candles work too, but they are a fire risk exactly when help is slowest to arrive.
A radio that needs no mains power
When mobile networks fail, broadcast radio is how the authorities reach you. All 24 guides list a battery, solar or crank radio.
Batteries and a charged power bank
Buy batteries in the sizes your torch and radio take. Lithium cells keep for years and work in the cold. A 20,000 mAh power bank charges a phone four or five times; keep it topped up with its cable next to it.
Warmth
In winter, an outage without heating is the real danger. Gather the household in one room, close the doors, and layer up with blankets, hats and sleeping bags. Only use a heater that is rated for indoor use, with a carbon monoxide alarm and some fresh air.
Cash
Keep cash in small notes. Sweden suggests about 1,000 SEK (≈ €90) per adult.
The first hour
- Check whether it's just your home (fuse box) or the whole street.
- Switch off sensitive appliances to protect them from the surge when power returns. Leave one light switched on so you know when it's back.
- Turn on the radio and listen for official information.
- Keep fridge and freezer doors shut.
- Fill containers with tap water while there is still pressure.
- Check on neighbours who are elderly or rely on medical equipment.
Never use a barbecue, camping stove or generator indoors
They produce carbon monoxide, which you can't see or smell. Germany and Poland recommend a CO alarm in every home that heats or cooks with gas.