Energy monitors: Smart meters and energy monitors explained What is a smart meter?

A First Utility smart meter Smart meters - like this one from First Utility - will replace your existing gas and electricity meters.

Confusion over smart meters is rife. We’ve found that many people don’t know the difference between a smart meter and an energy monitor, and several people who think they have a smart meter actually have an energy monitor. 

Here we explain exactly what smart meters are and how they differ from energy monitors, plus you can take a look at our video guide to smart meters.

Smart meters – what can they do?

Smart meters are high-tech electricity and gas meters that will replace your existing meter. They will measure your exact gas and electricity use and, most importantly, send all the information back to your energy supplier – meaning no more estimated bills.

The government plans to roll out smart meters to homes across the country at a cost of at least £11 billion, starting in autumn 2015 and finishing in 2020.

How are smart meters different from energy monitors?

Smart meters are much more sophisticated than energy monitors, which simply give you a good estimate of the amount of electricity you are currently using. See What is an energy monitor? to find out more about what energy monitors can and can’t do.

As smart meters transmit regular meter readings to your supplier automatically, they will remove the need for your meter to be read and you should get accurate bills based on your actual usage.

Smart meters also offer additional possibilities for the future – such as improved ‘time-of-day tariffs’ offering cheaper rates at off-peak times to smooth out national energy usage through the day. Plus, they will make it easier to sell your own micro-generated electricity (such as from a solar panel or home wind turbine) to the National Grid.

Importantly, smart meters will actually replace your current meter, whereas energy monitors simply clip on to your power cable.

Will a smart meter show me how much energy I'm using?

A smart meter itself doesn't tell you much about your energy usage. But when you're upgraded to a smart meter you'll also receive a handheld in-home display unit, which will let you see how much gas and electricity you're using in real time, as well as how much it costs.

For now, you can buy separate energy monitors that monitor your electricity use (most can't measure your gas use). Best Buy energy monitors start from around £35. Our video explains the differences between a smart meter and an energy monitor.

Smart meter

Smart meters record and send information about energy usage to your energy company 

Will smart meters save me money?

While smart meters will mean more accurate bills - and remove the costs of meter readings which are currently added to your bills - they themselves will not save you money. 

You’ll only save money on your energy bills if you actively use the information provided to see where you could reduce your energy consumption, and then make an effort to do so.

According to government estimations, the average customer will save £23 a year on their energy bills by 2020 as a result of the roll-out, dependent on households actively changing their energy-usage habits. 

Take a look at our guides to cutting your energy bills and using less electricity to help you make a change to your energy bills. 

Will a smart meter cost me money?

While having a smart meter installed is free, you may incur the cost indirectly through your bills. 

At the moment, the roll-out, at an estimated cost of at least £11 billion, is being led by the energy companies with no checks in place to make sure that costs don't spiral.

This cost will be paid by consumers through their energy bills, so we want to make sure it is as low as possible, which is why we are campaigning to ensure the government reviews the smart meter roll-out. Find our more about the smart-meter roll-out and our . 

How can I get a smart meter?

Unlike energy monitors, which you can buy in the shops and set up yourself, smart meters need to be installed by your energy company. The government hopes to have smart meters in 80% of homes by 2020, and is currently putting forward plans for the roll-out. 

Some energy companies, such as British Gas and First Utility, have already started rolling out their own smart meters to customers. Other suppliers will soon be obliged to begin their roll-outs too, once the government has finalised its plans. Find out more about the smart meter roll-out.

smart meter installation

Smart meters need to be installed by a professional

How will my smart meter be installed?

Once the smart meter roll-out begins, your energy company will get in touch to arrange a suitable time and date for your smart meter to be installed. The installation itself will be carried out by a trained installer from the energy company. British Gas estimates that a typical smart meter installation takes 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, your energy company may offer to carry out an energy-efficiency inspection of your home, but you're not obliged to take up any of its recommendations, or buy any additional products.

Take a look at our video of a smart meter being installed to see what is involved.

How big is a smart meter?

You'll get two smart meters – one for gas and one for electricity. The smart gas meters are about the same size as current gas meters, while you may find that your electricity smart meter is slightly bigger than the old-style meter you have now. 

Your gas smart meter will be battery-powered and the electricity smart meter will be plugged into the mains.

Are smart meters safe?

So far, there has been no medical evidence to suggest that smart meters are unsafe for people.

How often will my smart meter need to be replaced?

Smart meters will need to be replaced around every 10 years – which is more often than current gas and electricity meters. Again, 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.

Will having a smart meter affect me switching energy suppliers in future?

Long term, it's hoped that smart meters will make it quicker to switch energy suppliers – in theory, a smart meter can be instructed to send information about your energy usage to a new energy company instantaneously.

Up until now, those getting a smart meter installed ahead of the national roll-out in 2015 who later wanted to switch gas and electricity providers, may have had to have their meter switched to 'dumb' mode, in effect reversing their move to smart metering, or have their smart meter replaced with a traditional-style meter altogether.

The government is now taking steps to make sure that once you move to a smart meter, you will continue to be able to use the smart functionality, even if you decide to switch suppliers. From the end of 2013, if you switch to a supplier who has provided you with a smart meter, your new supplier will not be able to replace that smart meter with a dumb meter and must either rent your previous supplier’s meter or install its own new smart meter. 

As of May 2013, the government says it is also considering forcing energy companies who take on smart meter customers from another supplier to continue providing remote meter readings.

It's hoped that these measures will give early adopters of smart meters greater confidence in the technology.

If you are thinking of switching energy supplier, you can compare gas and electricity suppliers using Which?'s independent online switching service. 

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