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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.

Around 14.9m smart meters are installed so far, though they’re not being installed fast enough to fit them in every home by the end of 2020 as originally planned. The government has recently extended the deadline, giving suppliers an extra three years to fit at least 85% of homes with smart meters.

Read on to find out why smart meters are being rolled out, why there have been 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 and there have been delays with many parts of the roll-out since.

Completing the national roll-out is 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 2019, energy suppliers had installed more than 17m 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 the number of smart meters installed per quarter by large energy firms is slower than last year

What happens during the smart meter roll-out?

Your energy company will contact you to arrange 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. Find out more about how smart meters work.

So far, most smart meters installed are first-generation ones. Companies are now installing second-generation meters, which will form the bulk of the smart meter roll-out. So far around 2.3 million of these have been installed (correct November 2019).

First and second-generation smart meters

There are two types of smart meter: first and second-generation. You might also hear these referred to as SMETS1 and SMETS2. SMETS stands for Smart Metering Equipment Technical Specification.

Most of the 14.9m smart meters fitted so far are first-generation smart meters. This is 7.1m more than the number it was originally predicted would be installed.

First-generation meters aren’t fully compatible with the network and switching supplier can cause it to revert to being a ‘dumb’ meter and you’ll have to submit meter readings again. Find out more, and what you can do in smart meter problems and how to solve them.

Energy companies are now installing second-generation meters (which don’t have this problem).

All suppliers could install first-generation meters until 5 December 2018, while energy regulator Ofgem let 12 suppliers continue installing them until 15 March 2019. This was to help them transfer smoothly to installing second-generation meters. These are British Gas, E, Ecotricity, EDF Energy, Eon, First Utility, Npower, Ovo, Scottish Power, SSE and Utility Warehouse.

This ‘end date’ (after which smart meters installed didn’t count towards companies’ totals) 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 could install first-generation prepayment energy meters, and count them towards their total, until 15 March 2019.

Even though the ‘end date’ has long passed, there’s no guarantee that energy providers have stopped installing first-generation meters, though it’s much more likely. To be sure, check with your supplier before you agree to have a smart meter fitted.

Second-generation meters are fully compatible with the network and being installed in small but growing, numbers. Around 14.9m were installed by the end of June 2019, Smart DCC announced. Find out if your energy supplier is installing smart meters yet.

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 in future, 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.

The nationwide installation of smart meters is a key part of the shift from standard, passive electricity grids to 'smart grids'. These use digital technology so network operators can predict much more accurately how much electricity is needed by the country, and when, so they can better match supply with demand.

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. Find out more in our guide to smart meter essentials.