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Smart meters explained

Smart meter roll-out

By Sasha Baker

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Smart meter roll-out

What's the latest on the smart meter switchover and how does it affect you? Is it delayed? When will you get a smart meter? We answer your questions about the smart meter roll-out.

Energy companies are in the process of replacing all old-style gas and electricity meters with smart meters. 

Smart meters measure your exact gas and electricity use and then send 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, intended to be cheaper to be cheaper and more efficient, and incorporate smart home products, electric cars and more.

Over 19.5m smart meters have been installed in homes 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 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 and why there have been delays so far, or jump ahead to find out about the smart future.

Smart meter roll-out: the story so far

The official national smart meter roll-out began in 2016 and was originally planned to finish in 2020. However suppliers now have an extra four years to keep installing meters.

The roll-out 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.

As of March 2020, energy suppliers had fitted more than 19.5m smart meters in homes in Britain. Installations were halted at the start of lockdown but have since started up again.

Smart meters installed by large energy companies

But the large energy firms need to install more than 46m meters in people's homes in total. Government figures reveal that the number of smart meters installed in 2019 was nearly 500,000 lower than the previous year, and the first quarter of 2020 saw just under 1 million smart meter installations for the first time since 2016.

What do smart meters do?

If you don’t already have smart meters, your energy company will contact you to arrange to install them, or you can request an appointment from your energy company.

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

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 smart meters fitted so far are first-generation smart meters. This is at least 7m more than the number it was originally predicted would be installed.

First-generation meters weren't fully compatible with the wireless network when they were installed. Switching supplier when you have one 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.

Second-generation meters are connected to the DCC’s wireless network when they’re installed and so don’t have this problem.

So far, most smart meters installed are first-generation ones. Even though the ‘end date’ has long passed, there’s no guarantee that energy providers have stopped installing first-generation meters.

All suppliers should now be installing second-generation smart meters. To be sure, check with your supplier before you agree to have a smart meter fitted.

Since 15 March 2019 any first-generation meters  installed have not counted towards targets. The second generation smart meters will form the bulk of the smart meter roll-out, and around 4.3 million of these had been installed in homes by the end of March 2020.

By the end of 2020, energy companies are meant to either enrol 'dumb' first generation smart meters onto the DCC network, or replace them with second generation smart meters. As of May 2020, 313,000 SMETS1 have been migrated onto the network, making it hard to see that the targets for the end of 2020 will be met.

A smart future 

Smart meters could 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 flatscreen 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 from solar panels.

Find out more about the Smart Export Guarantee which pays households who put renewable electricity into the grid.

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 – potentially saving you money. Smart time-of-use tariffs are available already from some companies, and offer cheaper rates for electricity at certain (less popular) times of day.

There are community energy schemes taking advantage of this, such as Energy Local which matches local renewable generation with users nearby in real-time so they only pay for electricity used on top of what their local generator produced.

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.