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Smart meters explained

Smart meter roll-out

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Smart meter roll-out

What will the smart meter switchover mean for you? Will it cost you anything? Is it delayed? We answer your questions about the smart meter roll-out.

The government has called on energy companies to replace all old-style gas and electricity meters with smart meters. 

Smart meters measure your exact gas and electricity use and then send all the information back to your energy supplier, without the need for someone to come and take your meter readings.

But the purpose of the smart meter roll-out is far broader. They’re part of the wider ‘smart grid’ planned by the government to be cheaper and more efficient, and to incorporate smart home products, electric cars and more.

Read on to find out why smart meters are being rolled out, progress and delays so far, or jump straight to find out about the smart future.

When are smart meters being installed?

The official national smart meter roll-out began in 2016 and will finish in 2020. The smart meter infrastructure went live across the UK, the Department for Business, Energy and Industrial Strategy (BEIS) confirmed, on 30 November 2016.

The start date was pushed back multiple times.

Completing the national roll-out will be an enormous logistical and technical challenge for the energy industry, involving visits to around 30m homes and small businesses, and installing about 53m new meters.

By September 2018, energy suppliers had installed more than 13.64m smart meters in homes in Britain.

But the large energy firms need to install more than 46m meters in people's homes in total. The government revealed that meters were installed at a slower rate in the first half of 2018, than at the end of 2017.

What happens during the smart meter roll-out?

Energy companies will contact households to install a smart meter, or you can request one from your energy company.

Once fitted, smart meters will send information about your energy use to a central data body called the Data and Communications Company (DCC). The DCC's wireless network will then link each home's smart meter with their supplier, network operators and energy-service companies. 

However, many energy companies are still installing smart meters that aren't fully compatible with the network; these are known as SMETS1 (Smart Meter Equipment Technical Specification) meters. If you have one of these meters and you switch energy supplier, it may revert back to being 'dumb', and you'll have to take meter readings again.

If you have a SMETS1 smart meter and you switch supplier, your smart meter may revert back to being 'dumb'.

Find out more about why smart meters can turn dumb, and what you can do about it – go to getting a smart meter installed.

Suppliers can continue to install these SMETS1 meters until 5 December 2018. This is the ‘end date’ for SMETS1 installations, although energy regulator Ofgem is allowing 12 suppliers to continue installing them beyond this deadline, until 15 March 2019, to help them transfer smoothly to installing SMETS2 meters. This includes British Gas, Eon, First Utility, Npower, Ovo, Scottish Power and Utility Warehouse.

The ‘end date’ was pushed back three months (originally it was 13 July 2018). The government said this was because ‘no large energy supplier will be able to complete the transition by July without significant risk’, including ‘issues remain[ing] with some meters’, and ‘insufficient time’ to find and resolve them. It said ‘consumers […] would bear the consequences’.

Firms can install SMETS1 prepayment energy meters until 15 March 2019.

SMETS2 meters are fully compatible with the network. BEIS said that, with the smart meter data and communications network live, 'energy suppliers can start rolling out the next generation of smart meters, putting households and businesses in control of their energy use'.

Some 47,000 SMETS2 meters had been installed in homes by the end of September 2018, government figures showed. Find out if your energy supplier is installing smart meters yet.

Why should I get a smart meter?

It's hoped that smart meters – when used alongside the in-home display (IHD) – will help people become more aware of how much energy they're using, so they'll take steps to reduce their energy consumption.

The organisation responsible for telling us all about smart meters, Smart Energy GB, ran a survey that found 85% of people with a smart meter said they had changed the way they do things at home to use less energy. 

But the same research found that 95% of people who don’t have a smart meter, but know what one is, had done the same in the last six months.

When we asked hundreds of Which? members* with smart meters what they think of them, nearly six in ten (59%)  said their smart meter and IHD changed their understanding of energy use and costs to some extent. But 41% said they hadn’t. 

This was mainly because they knew the information already (43%), don’t use the IHD (27%), or don’t understand the IHD (13%).

59% of you said your smart meter and IHD changed your understanding of energy use.
41% said it didn't.


Under EU legislation, 80% of consumers will need to have smart electricity meters installed by 2020 as part of a larger plan to help European nations meet energy-efficiency targets. But Britain has set itself an even more ambitious target of fitting every home with a smart meter.

The nationwide installation of smart meters is a key part of the shift from standard, passive electricity grids to 'smart grids'. Smart grids use digital technology to better manage electricity demand and production, and will be able to communicate directly with 'smart' homes or appliances, and offer more flexible tariffs.


A smart future 

So far we’ve seen just the tip of the smart iceberg. Smart meters bring huge potential for you, your energy company, and the wider energy system.

For you, a smart meter is the means to get in-depth information about your energy use – for example, how much you’re spending on running your flat-screen TV. Studies are being done into how smart meters could alert you if elderly relatives are showing signs of dementia (by revealing unusual patterns in eating and sleeping shown by electricity use), or dangerously under-heating their homes in winter.

You should be able to switch suppliers much more quickly, such as via an app. Plus you could trade energy with your neighbours or sell surplus electricity you’ve generated.

Your energy company will get automatic meter readings, up to every half hour, so it can offer you tariffs tailored to when you use energy – and save you money. Smart time-of-use tariffs are available already, and offer cheaper rates for electricity at certain (less popular) times of day.

For the wider energy system, smart meters will enable network operators to predict much more accurately how much electricity is needed by the country, and when, so they can better match supply with demand. This is expected to reduce the cost of providing energy.

Smart appliances connected to the grid in future could be used to help manage surges in demand (for example, millions boiling the kettle at half time during the FA cup final) by switching off momentarily, and electric cars used as batteries to store excess-generated electricity. Network operators will have detailed information on power cuts so they can better manage them.

The more of us who have smart meters, the greater the benefits, according to Ofgem. The government says the smart network benefits ‘depend on a critical mass of SMETS2 meters being installed’.

You can object to having a smart meter installed if you really don't want one. Read our guide on your rights to refuse a smart meter.

*(Online survey: 473 Which? members, November 2017.)