Skip to main content

What to do in a power cut

woman sitting in the dark on her mobile phone - What to do in a power cut

We’re not really used to power cuts here in the UK. Compared to places like Pakistan and South Africa, we hardly ever get them. However, we’re not Singapore or Iceland – two of the countries rated with the highest quality electricity supply in the world.

And with the biggest UK power outage in a decade happening in August 2019, causing chaos across the country, it’s wise for homeowners to be prepared in the event of one happening again. So this is your friendly guide to what causes power cuts and what to do if you find yourself in one.

Table of contents

  1. Wait! Is it really a power cut?
  2. What to do in a power cut
  3. What causes power cuts?
  4. How long do power cuts last?
  5. Who to call in a power cut
  6. How to protect your equipment in case of a power cut
  7. Will my gas boiler work in a power cut?
  8. Can a power cut affect central heating?
  9. So now you know what to do if there’s a power cut

Wait! Is it really a power cut?

The very first thing you should do is check if it’s a bona fide power cut.

  1. Look outside and check if the street lights are on
  2. Check if your neighbour’s lights are on. If your neighbours’ houses are lit up like Christmas trees and the street lights are shining bright, your problem is closer to home – in fact, it’s inside your home. Your next stop is your fuse box
  3. Grab your smartphone and switch on the torch function; we’re going to find your fuse box (it’s usually under the stairs or up high near the front door)
  4. Open up your fuse box panel. You’re checking to see if one or all of the switches have ‘tripped’, aka switched themselves off as an emergency precaution because of a surge or fault in the circuit
  5. If all the switches are on and you’re on a prepayment meter, make sure you have enough credit
  6. If you’ve got plenty of credit, there are no tripped switches and it seems like a total mystery, it’s time to call a qualified electrician. Don’t attempt to fix anything yourself.

What to do in a power cut

If you checked outside and the street lights are off, and your neighbours are also in the dark, it’s a power cut. Here’s what to do:

  1. Don’t assume your power company knows about it. Give them a ring or check online
  2. Stay calm
  3. If you have children who are awake, make sure you reassure them that it’s not dangerous, soothe them and explain what’s happening (with a bit of luck it’s the middle of the night and they will just stay asleep through it)
  4. Unplug sensitive appliances such as TVs, satellite equipment and computers
  5. Switch off and unplug heated appliances like fires, ovens, grills, hobs, the clothes iron or any heated hair straighteners or curlers, in case you forget they were on when the power comes back on
  6. Leave a light switched on so you know straight away when the power returns
  7. If you have elderly or vulnerable neighbours, pop round and check on them to make sure they are safe and comfortable
  8. Livestock, fish and pets may be vulnerable during a power cut. Make sure they’re all ok
  9. Don’t open your fridge or freezer if you can help it – you need to keep your food as cold as possible. The power cut shouldn’t last very long, but if your frozen food defrosts you’ll have to eat it that day or chuck it away
  10. Many central heating systems and water heaters won’t work because they rely on electricity to switch on
  11. Conserve your laptop and smartphone battery life by using them sparingly
  12. When the power comes back on, turn your appliances back on slowly, one at a time.

What causes power cuts?

Our power lines are the most vulnerable point in the UK’s National Grid system. Any number of things can interfere with power lines and energy generation:

The weather

We get our fair share of rain, wind, snow, floods and storms in the UK, don’t we? In fact, weather and natural disasters are the primary cause of electrical failures across the globe. However, here in the UK, we’re lucky to have relatively mild weather, with very few earthquakes and hurricanes. Flooding is the UK’s biggest natural threat to a consistent power supply.

Intermittent power sources like Wind Energy

After the August 2019 blackout, there was much discussion about whether our country’s increasing use of wind power was to blame. It wasn’t, but here’s why people questioned it:

While wind power is infinite energy and fossil fuels definitely aren’t, wind power is an inconsistent, intermittent and unreliable source of energy, which means we could never have wind as our sole source of energy.

We need a number of different energy sources to power our National Grid for the times when winds are low. In these instances, our more reliable coal and gas power stations have to increase their energy generation to make up for it. Unusually high winds could also cause surges that need expensive equipment to guard against and prevent outages from happening that way.

So it follows that the more of the grid the UK dedicates to wind, the fewer flexible power stations it’s maintaining when the wind is too unreliable.

Maintaining 50Hz

To maintain power throughout the country, our National Grid has to maintain a 50Hz frequency. To use a crude analogy, it’s like Sandra Bullock in Speed, having to drive her bus at a steady 50mph to stop the bomb going off – only in this instance it’s not a bomb going off, just our landing lights.

If the National Grid’s overall frequency goes too much over or under 50Hz, there are big problems. If our demand drops, but the supply remains high, the frequency rises too high over 50Hz. If our demand is high but the supply drops (as happened in the 2019 blackout when two power stations disconnected at the same time), the frequency drops too low below 50Hz. This can badly damage the National Grid infrastructure and cost millions to repair, so there’s an automated fail-safe system that kicks in to protect the grid by cutting off parts of it to reduce demand and get the frequency back to 50Hz. Thanks, Keanu.

How long do power cuts last?

Most power cuts don’t last very long and your electricity company will be on the case to quickly get things back on track.

Who to call in a power cut

Call your electricity company. If you can’t remember who supplies your electricity, check one of your bills.

How to protect your equipment in case of a power cut

There are four steps you can take to protect your electrical appliances:

  1. Buy appliances with the BSI Kitemark
  2. Make sure you don’t store items in damp places with no ventilation
  3. Fit surge protection devices to sensitive appliances such as computers and televisions. These can be purchased from your local DIY shop or electrical retailer
  4. Get electrical cover for peace of mind during a power outage.

Will my gas boiler work in a power cut?

In most cases, your boiler won’t work in a power cut. Even though it’s a gas boiler, you switch it on using electricity.

Can a power cut affect central heating?

Yes. Most central heating systems are powered by electricity, so in the event of a power cut, wrap up warm and make sure babies, young children, elderly and vulnerable people are also snug.

So now you know what to do if there’s a power cut

If you want peace of mind over the smooth-running of your electrical appliances – big and small – HomeServe’s electrical insurance is on hand for those unexpected breakdowns and unfortunate damages.

Share this post

Share this post

Still looking for more help & advice?

Our help & advice articles cover Plumbing, Home heating, Electrical, Energy-saving and Home maintenance.

View all articles