Smart Home Energy Saving Guide 2026: Where Automation Really Cuts Consumption

A smart home genuinely cuts energy use when it tackles heating first: a smart thermostat or room-by-room smart radiator valves such as the tado X act on the biggest item in the bill. Next comes measurement (smart plugs and energy monitors) to find waste, then a few simple automations; gadgets that control neither heating nor power-hungry appliances save almost nothing.

This guide is not based on in-house trials: it compares devices using manufacturer specifications, independent reviews and verified buyer feedback. Savings always depend on your home, its insulation, your heating system and your habits, so the figures below are orders of magnitude, never promises.

Where a home’s energy goes

According to Eurostat, space heating accounts for roughly two-thirds of the final energy used by households in the European Union. Hot water comes a long way behind, followed by lighting and appliances. That split sets the priorities: a device that controls heating better will almost always do more than a smart bulb.

The French energy agency ADEME estimates that lowering your heating setpoint by 1 °C cuts heating consumption by about 7%. That is exactly what a good smart thermostat does: it lowers the temperature when nobody is home, at night or in empty rooms, without you having to think about it. Devices on standby use little power individually but they draw it around the clock, which is why it pays to measure them before switching them off.

How to choose

Compatibility with your heating

Check this first. A wired thermostat connects to a boiler or heat pump (on/off dry contact or a modulating protocol depending on the model); smart radiator valves screw onto the valves of wet radiators; electric heaters are usually controlled by pilot wire or are smart models themselves. Use the manufacturer’s compatibility checker before you buy.

Protocol: Matter, Thread, Wi-Fi or Zigbee

Matter lets devices from different brands work together in Apple Home, Google Home, Amazon Alexa or SmartThings. Thread is a low-power mesh network suited to battery devices. Wi-Fi needs no bridge but loads your home network as devices multiply. Our Matter and Thread guide explains these choices in detail.

Energy measurement

A plug that measures instantaneous power and totals the kWh tells you what an appliance really costs to run. A monitor installed in the consumer unit gives the whole-home picture, including any solar production.

Local control and subscriptions

Check whether automations run without the manufacturer’s cloud and whether some features require a subscription. It matters for reliability as much as for long-term cost.

The devices to prioritise in 2026

tado Smart Radiator Thermostat X Starter Kit: best overall

The tado X starter kit pairs a smart radiator thermostat with the Bridge X, which acts as a Thread border router. The thermostat is Matter compatible, fits most radiator valves thanks to the supplied adapters and runs on a rechargeable battery. Everything can be controlled from the tado app or from Apple Home, Google Home and Alexa.

Strengths: room-by-room control, tool-free fitting on wet radiators, a complete ecosystem (wired thermostat, sensors, extra valves). Limits: the X range is not compatible with older tado V3+ products, and some advanced automations, such as automatic geofencing, are part of the optional Auto-Assist subscription. Who it’s for: homes with wet radiators that want to stop heating empty rooms.

Netatmo Smart Thermostat: the safe choice for a boiler

The Netatmo thermostat replaces a standard room thermostat and switches the boiler through a relay. Its Auto-Adapt feature anticipates when to start heating based on your home’s insulation and the outdoor temperature, and the app sends a monthly energy report. It works with Apple HomeKit, Alexa and Google Assistant.

Strengths: simple settings, regular reports, discreet design. Limits: a single heating zone unless you add smart valves, and on/off control that does not suit every heat pump. Who it’s for: houses and flats with an individual boiler and one central thermostat.

TP-Link Tapo P110M: the most accessible metering plug

The Tapo P110M is a Matter-certified Wi-Fi plug that measures the consumption of whatever is plugged into it. The app shows kWh history and lets you enter your electricity rate to estimate cost. It works with Apple Home, Alexa, Google Home and SmartThings, and its compact shape leaves the neighbouring socket free.

Strengths: native Matter, quick setup, ideal for auditing power-hungry appliances. Limits: 2.4 GHz Wi-Fi only, fewer advanced features than Shelly. Who it’s for: anyone who wants to measure several appliances on a modest budget.

Shelly Plug S Gen3: the plug for advanced users

The Shelly Plug S Gen3 meters power, handles loads up to 2,500 W, is Matter certified and needs no hub. It stands out for its local API and its popular Home Assistant integration, which lets you trigger automations on a power threshold (for example, a notification when the washing machine has finished).

Strengths: local control, many automation options, Wi-Fi range extender function. Limits: more technical settings, and the 2,500 W limit rules out large portable heaters. Check the plug format sold for your country too. Who it’s for: Home Assistant users and anyone who wants fine-grained automations.

Shelly Pro 3EM: the whole-home view

The Shelly Pro 3EM is a DIN-rail energy meter with current clamps that works on single-phase and three-phase supplies. It measures in both directions, consumption and production, which makes it useful with solar panels. It comes in 120 A and 400 A versions, with a stated accuracy of 1%, and connects over Wi-Fi or Ethernet, locally or through the cloud.

Strengths: complete view of the home, solar self-consumption tracking, history stored on the device. Limits: installed in the consumer unit, a job for a qualified electrician. Who it’s for: homes with solar panels, a heat pump or an EV charger. Our home energy monitor comparison also covers options that need no wiring work.

Aqara Presence Sensor FP2: heat and light only occupied rooms

The FP2 uses millimetre-wave radar that detects people even when they are still, unlike classic infrared motion sensors. It covers up to 40 m², can split a room into 30 zones, tracks several people and runs on 2.4 GHz Wi-Fi without an Aqara hub, with Apple Home, Alexa, Google Home and Home Assistant.

Strengths: reliable detection of someone reading or working, customisable zones. Limits: USB cable power, zone setup takes some care. Who it’s for: anyone who wants lights and heating off in rooms that are genuinely empty.

Comparison table

See our full selection of smart thermostats and energy monitors in the catalogue.

A worked example in kWh

A device drawing 10 W around the clock, such as a set-top box or speaker left on standby, uses 10 W × 8,760 hours, or about 88 kWh a year. At an example rate of 0.25 euro per kWh (replace it with your own tariff), that is about 22 euros a year for a single device. A smart plug that cuts these devices at night and while you are out removes a good share of it.

The same logic applies to heating: if your home uses 10,000 kWh a year for heating, lowering the average temperature by 1 °C corresponds, using ADEME’s rule of thumb, to about 700 kWh less. Control that lowers the setpoint in empty rooms and at night works exactly on this lever.

Automations that really save energy

• Night and away schedule: lower the heating setpoint at night and during the day when the home is empty.
• Open-window detection: turn the radiator off while a window is open for ventilation.
• Grouped switch-off: a “Leaving home” routine that turns off lights and the plugs of standby devices.
• Room-by-room presence: switch off lights and supplementary heating when the sensor no longer detects anyone.
• Solar: start a programmable appliance when production exceeds consumption, if you have balcony solar panels or a rooftop system.

Mistakes to avoid

• Starting with lighting: LEDs already use little power; the real gains are in heating.
• Buying without checking compatibility: boiler, heat pump, radiator valves and plug format must all match.
• Plugging a portable heater into a small smart plug: respect the maximum load stated by the manufacturer.
• Collecting apps: favour Matter or a central hub to manage everything in one place.
• Trusting guaranteed savings: advertised percentages depend on the home; measure before and after.

Installation and safety

Smart plugs and radiator valves install without tools. A wired thermostat connected to the boiler or a meter fitted in the consumer unit, however, means working on an electrical installation: switch off the power and, if in any doubt, call a qualified electrician. Never plug in an appliance whose power exceeds the smart plug’s rating, and avoid daisy-chained extension leads.

Our verdict

For most homes heated by wet radiators, the tado Smart Radiator Thermostat X Starter Kit is the most effective starting point because it targets the largest consumption item. With a boiler and a single central thermostat, the Netatmo Smart Thermostat remains a simple, reliable choice. For metering on a budget, the Tapo P110M is the most accessible, the Shelly Plug S Gen3 the most flexible, and the Shelly Pro 3EM gives the complete picture, especially with solar. To go deeper on heating, read our smart thermostat and heat pump guide.