Electrical advice
What to do in a power cut
26 Mar 2021 • 6 minutes
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.
The very first thing you should do is check if it’s a bona fide 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:
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:
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.
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.
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.
Most power cuts don’t last very long and your electricity company will be on the case to quickly get things back on track.
Call your electricity company. If you can’t remember who supplies your electricity, check one of your bills.
There are four steps you can take to protect your electrical appliances:
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.
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.
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.
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