Which? uses cookies to improve our sites and by continuing you agree to our cookies policy.

Smart home products and systems

Smart thermostats and lighting control systems

By Liz Ransome-Croker

Article 2 of 5

We explain how you can control the lighting and temperature in your home using smart home thermostats and lighting-control systems.

Put us to the test

Our Test Labs compare features and prices on a range of products. Try Which? to unlock our reviews. You'll instantly be able to compare our test scores, so you can make sure you don't get stuck with a Don't Buy.

One of the biggest smart home innovations to have sparked people's attention is smart energy management systems, such as smart thermostats, that put you in control of your heating and electricity. 

Smart thermostats, from brands such as Nest, Honeywell and Hive, claim to help you save money on your energy bills, and the same goes for smart radiator controls. Plus, by 2020 we'll all have a smart meter in our home sending energy usage data to our energy supplier, meaning no more inaccurate estimated bills. 

And it doesn't stop at your heating  – new smart lighting systems mean you can turn your lights on and off from wherever you are, so you wont waste energy if you forgot to switch your bedside lamp off as you left the house. 

In this guide you can find out more about:

Including how much they cost upfront, whether they can make life easier and knock money off your energy bills, and the pros and cons of going smart.

Smart thermostats 

Smart thermostats allow you to control your heating by changing the temperature or by turning it on or off from your smartphone or tablet. This means that if you're away from home and realise you've forgotten to turn off your heating, you can simply do so  – even if you're on the other side of the world. 

Some also enable you to set different temperatures in different rooms, but this will cost a lot more, and others allow you to control your hot water or air conditioning as well. 

A few monitors go even further: turning off the heating when it detects that everyone is out of the house, using the weather to decide the temperature it should be set at, or using the GPS location feature on your phone to turn it on when you get close to home, so everything is toasty when you walk through the door. 

We've tested smart thermostats, including those from Hive, Nest, Tado and Netatmo. Jump straight to our smart thermostat reviews to find the best.

Will a smart thermostat save me money?

Some companies claim that this more efficient and nuanced heating control could save hundreds on your energy bills.

But we'd suggest that you take these savings with a pinch of salt, as they're often worked out based on someone who has their heating on a constant temperature all day, every day. It also depends on a lot of other factors, such as how well insulated your home is. Some smart thermostats cost up to £300 to buy, and some prices include installation while others don't, so you'll take a while to recoup costs. Some will also need replacement batteries every six months or so.

That doesn't mean you shouldn't buy a smart thermostat, though. If you like the idea of the convenience of adjusting your heating or hot water whenever and wherever you are, or if you have an unpredictable lifestyle, a smart thermostat could work for you. Find out more with our guide to who can save money with a smart thermostat.

What else can smart thermostats do? 

Some smart thermostats are truly 'smart', which by definition means the product can learn and adapt, as opposed to simply being able to connect to other devices. The Heatmiser NeoKit1, for example, is claimed to learn your habits, such as when you're in or out of the house and the temperature you like, and therefore adapts to you. 

A lot of smart thermostats also connect with other devices. Some can be bought alongside motion sensors and cameras, either to be used for security or to monitor your family, while others allow a range of compatible devices to connect with it. For example:

  • Nest Learning Thermostat connects to – the Yale Linus lock, which works with the Nest app to allow you to give visitors a temporary passcode to your home; the Lifx multicoloured LED bulbs that will automatically dim when no-one’s home; and the SkyBell video doorbell you can programme to record footage of your front door when the Nest Cam detects motion  – to name a few.
  • Netatmo smart thermostat connects to – camera with face recognition, outdoor lighting, carbon monoxide monitor and monitoring of home environment (eg. air quality).
  • Hive Active Heating connects to – smart plugs (which can be used to control some appliances) and security sensors.

For more information about security systems, visit our page on smart home security and monitoring. We've also tried out some of the popular smart systems these thermostats connect to. Find out what we thought by heading to our smart security system reviews.

Smart radiator controls

Smart radiator valves help to control your heating on a more micro level. They can be scheduled and controlled remotely using an app or, in some cases, an actual remote control. Some also claim to adjust to the weather and be able to learn from your habits, just like smart thermostats.

Should I choose a smart radiator valve or a smart thermostat?

Smart radiator valves give you greater control over having different temperatures in different rooms. They are also generally easier to install, so you won't need to pay installation costs.You could only get this functionality with a smart thermostat if you bought one that has a multi-room control, and the costs of additional valves can be prohibitive. 

You can buy smart radiator valves on their own for less than £50; one example is the MiHome Heating valve from Energenie, which costs £49 for one. But you can also buy them alongside smart thermostats, such as the Salus iT500, Tado, Netatmo and Honeywell Evohome

These can cost nearer £200 for 'starter kits', which might only include a couple of valves, and you may need to fork out for the installation as well. You can sometimes get them cheaper if you're buying a collection of gadgets together, so think about what you might want, and how many radiators you'll need to control, before you start looking.

Smart boilers 

Smart boilers are still in their infancy, and there are only a few out there. The most well-known is the Worcester Bosch Wave, which isn't strictly speaking a smart boiler, but instead a smart thermostat that connects to the Wave boiler, enabling you to turn it on and off when you're away from home.

British Gas has launched ‘Boiler IQ', which was the first boiler to be able to auto-detect faults. The boiler will be constantly monitored and as soon as a fault is detected, an alert will be sent to your phone. This means you should be able to catch problems before they cause any damage. 

Flow Energy has also launched a smart boiler, the Eco RF, that can be turned on and off or adjusted via an app. It too will also send alerts to your installer if something wrong with it. If the fault warrants it, the installer can even log into the machine remotely to fix it, saving the inconvenience of a home visit. You can read our Flow Energy Eco RF boiler news story to learn more.

Just want the best boiler? Head to our boiler reviews.

Smart meters 

There isn't really a choice when it comes to getting a smart meter by 2020 the government wants all homes in the UK to have a smart meter fitted.

Smart meters automatically deliver meter readings to your energy company through mobile networks, so you don't have to send them in when requested. Most also come with an in-home display that will deliver real-time information about your energy usage. If you act on these for example turning off lights you didn't realise were on and draining electricity you could save money. 

You can find out more about smart meters, including what you need to know about the government roll-out, in our full smart meters explained guide.

Smart light bulbs and lighting systems 

Smart lighting systems allow you to control the lights in your home from your phone or tablet, turning them on and off and, in some cases, dimming them or changing the colours. 

You can either:

  • Buy a smart light bulb or kit, and make an individual fitting or several fittings smart, if you want custom lighting options in your living room, for example. Some also link up with other smart products.
  • Set up a smart lighting system, such as Lightwave RF, which incorporates smart switches and dimmers that work alongside an app on your phone for flexible control options.

Some can also be scheduled ahead of time to suit your routine or for security purposes. This element isn't totally new, though you can already buy timers that you plug the light into for less than £10. You can also buy smart plugs for around £20 to £50, which you could use in the same way.

But these only work for lights that need to be plugged in, such as lamps, whereas smart lighting systems let you control a wide range of lights around your home, depending on what type of light fitting you have.

A good example of this is the Philips Hue lighting system. It's claimed to be able to connect up to 50 Hue LED bulbs in your home, which you can change the brightness of as well as the colour. There are apparently 16m colour options, including the ability to change the colour based on a photograph. You can also sync them with films, computer games or music to reflect what's happening on screen in your living room. 

We've put smart light bulbs from leading brands, such as LIFX, Philips, Hive and Osram to the test. Browse all our smart light bulbs reviews and find out which is best.

A starter kit, which includes the main connecting hub and three E27 or GU10 light bulbs, costs £149. Considering you can get a highly energy-efficient Best Buy LED bulb for less than £5, this is a very expensive party trick.

As well as matching your lighting to music, some standalone smart LED bulbs, such as the Olixar Light Beats Bluetooth Speaker Bulb, MiPow Playbulb and Sengled Pulse, actually play music too.

Some smart lighting systems and bulbs can add an additional level of monitoring and home control by connecting to other smart systems. For example, the LIFX bulb can connect to the Nest Learning thermostat so you can adjust your heating; the Nest Protect smoke alarm, flashing red if smoke is detected; and the Samsung SmartThings motion sensors, so lights are turned on when it detects motion.

Visit our guide to smart home security and monitoring to find out more about the smart products that aim to keep you and your home safe, and how different gadgets can connect to each other. 

You can also visit our smart home security system reviews, where our experts give their verdicts on whether popular systems are worth buying.

SHARE THIS PAGE