Do smart thermostats really save you money?Find out if smart thermostat claims hold up

08 December 2015

Man using smart thermostat and computer

Smart thermostats probably won't save you as much as manufacturers claim

Can a smart thermostat really knock hundreds of pounds off your energy bills? We dive into the detail to find out the truth behind smart thermostats' money-saving claims.

Smart thermostats - devices which can switch your heating on or off remotely via the internet - are the latest trend in home heating. Some manufacturers say the extra control and technology provided by a smart thermostat means your heating is only used when it's actually needed, slashing your bills. 

But our research has discovered that this claim isn't strictly true. Read on to find out what we discovered when we carefully scrutinised these claims to see if there's any substance to them.

Want to know which smart thermostats are best? Check out our smart thermostat reviews.

Smart thermostat claims 

These are the claims made by the major smart thermostat manufacturers:

  • Tado says that its £239 smart thermostat ‘will pay for itself within a year’, reducing your heating bills by between 14% and 26%. 
  • Netatmo claims that its smart thermostat will reduce the energy you use by 37%. 
  • British Gas says that its Hive smart thermostat ‘could save you up to £150 a year on your energy bills’.

But all these estimates assume that, before you started using the smart thermostat, you left your heating set to maintain a constant temperature during the day. So if you already turn the heating off when you're not at home, you’re unlikely to save as much as the manufacturers claim.

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A study carried out for British Gas states that the energy savings you achieve with the Hive would be much smaller if you previously had the heating on for only part of the day. 

It also reveals that in a scenario where the heating was previously just on for a few hours a day on weekdays, switching to Hive’s default schedule would actually cause you to use more energy.

Which? advice on smart thermostats

In short, be wary of the big headline savings claims made by smart thermostat companies. 

Unless you currently have the heating on a lot while you’re out of your home, the savings you make aren’t going to be large enough to save you hundreds of pounds a year. The easiest way to cut your energy bill is to compare prices and switch supplier - click the buttons, right, and see how much you can save.

What a smart thermostat can do is give you greater control over your heating. So if you unexpectedly stay out late, you can use your smart phone to turn it off so you're not wasting energy. Coming home from holiday? Then turn your heating on so you get back to a nice cosy home.

What's key to choosing the best smart thermostat for you is making sure you buy one with the features you need. Use our expert advice to buy the best smart thermostat.

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