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Smart meters explained

What to expect from a smart meter installation

By Sarah Ingrams

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Smart meter installation

What you need to know about smart-meter installation, including which companies are fitting them and what happens during an installation visit.

More than 17m smart meters are now fitted in homes. We tell you what you need to know if you haven’t had one installed yet, and how long they’re expected to last.

You don't have to accept a smart meter if you don't want one. However second-generation meters (which companies should be installing) don’t have the problems you might have heard about with their first-generation cousins.

Keep reading to find out what happens during a smart meter installation, or find out more about smart meters first. If you have a first-generation smart meter and are concerned it may stop working, read our page on smart meter problems and how to solve them

How can I get a smart meter?

Your energy company will get in touch to arrange a suitable time and date to fit your smart meter. Or you can contact it to arrange an appointment. Most energy companies will make an appointment in advance, so in the unlikely event that someone knocks at your door to make a smart-meter appointment, ask to see official ID to ensure they’re not a rogue trader trying to scam you. 

The installation itself will be carried out by a trained installer from the energy company or a company working for it. You will need to be at home during the installation appointment.

British Gas estimates that a typical smart-meter installation will take around 1.5 hours – but it will differ from property to property, and depend on where your current meters are located.

As part of the installation, you will be given an in-home display (IHD). This is a handheld digital device which shows how much electricity and gas you’re using, in real time, and how much it’s costing. The installer should show you how to use this. You may also be able to see your energy use via your online account or app.

Your energy company should also give you advice on saving energy in your home, and how to use your smart meter to do this. There's a code of conduct that smart-meter installers are required to follow, which forbids them from tying to sell you other products while they’re installing your smart meter.

You'll get two smart meters – one for gas and one for electricity (or just an electricity one if you don't have mains gas). The smart gas meters are slightly smaller than current gas meters, but you may find that your electricity smart meter is slightly bigger than the old-style meter you have now.

If you don’t want a smart meter installed, know your rights. You're not obliged to have one, and can ask your supplier to replace your old meter with a smart meter that has its communications switched off.

Before the installation

Before your smart meter is installed, your energy firm should tell you:

  • what to expect
  • how long the installation will take
  • if there's anything you need to do before the installation can happen (eg clear out the cupboard containing your meter or get access to the main fuse switch for electricity. In flats this can sometimes be behind a locked door so you’d need to arrange access with the building manager).

If you know that there’s something unusual about your home or meters, tell your energy company when you make the appointment, or at least several days in advance of your installation appointment.

This will help reduce the likelihood that the installation cannot go ahead because of something the installer needed to know. Things it’s worth telling your energy company about include:

  • If you have solar panels or generate renewable electricity another way
  • If your gas and electricity meters are very far apart (they need to ‘talk’ to each other which might require a special communications hub if this is a long distance)
  • If your meters are inaccessible (for example high up on a wall, behind a locked door or gate, in a very small cupboard)
  • If you currently have a multi-rate meter (for example Economy 7, Economy 10, a grey or white meter, or any meter that directly controls your central heating)
  • If you know your area has poor signal. Your energy firm may be able to check in advance if smart meters will be able to connect to the smart meter wide area network.

During the installation

When the engineer arrives, they will usually do a visual inspection of your boiler and other gas appliances to check they are working properly.

They will take final meter readings from your old meters before removing them – this makes sure your account is up to date. You can note them down yourself too for extra peace of mind.

During the installation, the electricity and gas will need to be switched off for around half an hour. The engineer will let you know when they are going to do this.

After fitting your smart meters, the engineer will check your gas supply by turning your gas back on and re-lighting any pilot lights in your boiler. If you have any mains-connected alarms, check that they are working correctly.

They will also do a test with a plug socket to check that things are working the same after the smart meter installation as before.

You should also be given advice on saving energy in your home, and shown how to use your in-home display.

Safety problems found by smart meter installers

During some installations, engineers sometimes identify potential problems unrelated to your smart meter, such as defective wiring, equipment that is very old, broken fuses or faulty boilers. In 2017 and 2018, around 635,000 problems were identified by engineers fitting smart meters, according to Smart Energy GB.

If a problem is found, the installer’s priority is to make it safe. Some problems may mean it’s not appropriate to install smart meters. If so, the installer will explain why, and tell you what work needs to be done (by you, your energy company or network operator).

Which energy companies have smart meters?

Energy companies are generally installing second-generation smart meters, although it’s worth double-checking that’s what you’ll get before you agree to an installation appointment.

British Gas has installed the most smart meters of any energy company, perhaps unsurprisingly as it’s the biggest. It has fitted more than seven million smart meters in homes so far.

Utilita says it has already installed smart meters for more than 1.1 million of its customers - and more than 90% of them now have a smart meter. It says it was the first UK supplier to install a smart meter in 2008.

It has previously said that it wanted to delay installing second-generation smart meters because first-generation meters are secure, cost-effective and give prepayment customers additional functionality that isn’t support by second-generation meters.

Utilita explained that first-generation smart meters have a keypad, so you can operate it yourself if there are problems or the network is down. Second-generation meters don’t have this option.

In fact, Utilita filed for a judicial review to delay the end date for installing SMETS1 meters for pay-as-you-go customers to 2020 but it was refused.

Want to pay less for energy? Use our independent switching service, Which? Switch to find the cheapest energy deal.

How often will my smart meter need to be replaced?

Smart meters will need replacing around every 10 years – which is more often than current gas and electricity meters. Your energy company will let you know when your smart meter is due to be replaced, and arrange a time and date for this to happen.

Your gas meter is battery-powered so, like traditional prepayment meters, will need to have its battery replaced when it goes flat. It should send a notification to your supplier when it needs replacing, but if you’re concerned, contact your energy firm. Electricity smart meters are mains-powered.

In-home displays can be either mains or battery-powered. If yours stops working, it won’t affect your smart meter.