Heating is the single biggest energy expense in most homes during winter. And the frustrating part? A huge chunk of it is wasted — on empty rooms being heated to the same temperature as occupied ones, radiators running full blast when a window is open, electric heaters left on when nobody's home, and appliances quietly pulling power 24/7 that you never notice until the bill arrives.
The fix isn't a smaller house or a thicker sweater. It's visibility and control. These five smart devices give you both — automated, room-by-room heating control plus whole-home energy monitoring that pays for itself in a season or two.
1. SONOFF TRVZB Zigbee Thermostatic Radiator Valve — The Biggest Winter Win
If you heat with radiators, this is where you start. The TRVZB replaces the manual knob on any standard M30 x 1.5mm radiator valve and gives each radiator its own smart brain. You set the temperature per room, create schedules per room, and the valve opens and closes to match — meaning the guest bedroom nobody uses doesn't get heated to the same 22°C as the living room.
The feature that saves you the most money: automatic open window detection. The second it senses a sudden temperature drop (because someone cracked a window), the valve shuts off until the window closes. No more pouring heat straight out into the garden.
Add frost protection, child lock, voice control through Alexa and Google Home, and 6 months of heating history in the eWeLink app — you can see exactly which rooms are costing you the most.
Perfect for: apartments and houses with hot-water radiators, especially multi-room setups where you only use some rooms during the day.
2. SONOFF SNZB-02P Zigbee Temperature & Humidity Sensor — Your Room Awareness
Your radiator valve knows how warm it is at the radiator. This sensor tells you how warm it actually is where you're sitting — and that difference is often huge. A room can read 22°C at the radiator but feel 18°C by the sofa because of a drafty window or a thick curtain.
With Swiss-made sensors delivering ±0.2°C accuracy and 5-second refresh rates, the SNZB-02P catches the real picture. Place one in every room you want to heat intelligently, and your automations get smarter: "when the living room drops below 20°C, turn the radiator valve up by two degrees — but only between 6pm and 10pm."
The CR2477 battery lasts up to 4 years, and you can download 6 months of temperature history as a CSV to spot patterns (like a bedroom that's always 2°C colder than the rest — probably time to check the insulation).
Perfect for: any room with a smart radiator valve, plus hard-to-heat spots like basements, guest rooms, and nurseries.
3. SONOFF S60 EU Smart Wi-Fi Plug with Energy Monitoring — Control Plug-in Heaters
Not everything in your house runs on radiators. Space heaters, oil-filled radiators, electric blankets, towel warmers, and heated mats all plug into standard sockets — and all of them get left on far longer than they need to be.
Plug the S60 between the socket and the heater, and now that heater is smart. Schedule it to warm up the bathroom at 6:45am before you shower and shut off at 7:30am. Set it to turn on when you're 10 minutes from home. Give it a runtime limit so an electric blanket can't stay on for 10 hours by accident.
The built-in energy monitor tracks daily, monthly, and yearly consumption — so you can actually see what that space heater is costing you per hour. Rated at 16A / 4000W with overload protection, child-safety shutters, and LAN control (works even when WiFi is down).
Perfect for: space heaters, electric blankets, towel warmers, bathroom heaters, portable AC/heater combos.
4. SONOFF POW Origin 16A Smart WiFi Power Meter Switch — For Hardwired Loads
Some of your biggest winter energy drains don't plug into a socket — they're wired directly, like your boiler, water heater, underfloor heating, or wall-mounted heater. The POW Origin is designed to be wired inline on those circuits (installed by an electrician) so you can control and monitor them the same way you would a smart plug.
You get real-time tracking of power, current, and voltage, 6 months of historical data exportable to Excel, overload protection with custom thresholds, and push notifications when consumption exceeds your set goals. If your boiler is drawing 2x what it should, you'll know within hours instead of discovering it next month.
Works with Alexa Energy Dashboard, Google Home, and eWeLink scenes. The flame-retardant PC V0 enclosure and upgraded terminal wiring are built for the kind of continuous loads winter heating actually puts on a device.
Perfect for: boilers, water heaters, hardwired electric heaters, underfloor heating circuits, towel radiators.
5. SONOFF POWCT Smart Power Meter — Your Whole-Home Energy Dashboard
This is the device that answers the question "where is all my power actually going?" The POWCT uses a split CT (current transformer) sensor that clamps around your main incoming cable — no wire cutting, no breaker replacement — and gives you a live reading of your entire home's power consumption up to 100A.
You see it all in one dashboard: real-time power draw, voltage, current, and running totals. If your bill suddenly jumps 30%, you can scroll back through 6 months of exportable data and find exactly which day it happened — usually traceable to a specific heater left on, a broken thermostat cycling constantly, or an old appliance drawing way more than it should.
It also supports solar panel monitoring, so if you've got panels, you can see generation vs. consumption in the same view. The built-in 2A relay can trigger an external contactor to shut off big loads automatically when thresholds are exceeded.
Perfect for: homeowners who want visibility into total consumption, people on time-of-use electricity plans, anyone with solar.
How It All Works Together: A Sample Winter Setup
Here's how these five devices connect into one coherent heating strategy:
- The POWCT on your main cable gives you the big picture — total house consumption at a glance.
- The POW Origin on your boiler circuit tells you exactly how much the boiler itself is drawing.
- The TRVZB valves on each radiator control how that heat gets distributed room by room.
- The SNZB-02P sensors in each room feed real temperature data back into the automation.
- The S60 plug handles any supplemental electric heating — bathroom heater, electric blanket, towel warmer.
Build it in stages. Most people start with one or two TRVZB valves plus a temperature sensor in the main living space, see the savings, then expand.
Frequently Asked Questions
Do I need a hub for these devices?
The S60 plug, POW Origin, and POWCT all run on WiFi — no hub required. The TRVZB and SNZB-02P are Zigbee devices and need a Zigbee hub like the SONOFF NSPanel Pro, ZB Bridge Pro, ZBDongle-E, or any Zigbee 3.0 gateway (including the Alexa Echo with built-in Zigbee hub).
Will the TRVZB fit my radiator?
The TRVZB fits standard M30 x 1.5mm radiator valve threads, which covers most European and UK radiators. The box includes adapters for the most common brands. If you're not sure, check the thread on your current manual valve — if it's 30mm with a 1.5mm pitch, you're good.
Do I need an electrician to install the POW Origin or POWCT?
The POW Origin wires inline on an existing circuit, so yes — a qualified electrician should install it. The POWCT is a clamp-on CT sensor that goes around (not through) your main cable, which is significantly less invasive, but we still recommend professional installation for anything near your main electrical panel.
How much can I actually save?
Varies hugely by home, climate, and starting point — but zone-based heating (TRVZB on individual radiators) typically cuts heating costs by 15–25% in multi-room homes, and whole-home energy monitoring usually pays for itself the first time you catch a surprise consumption spike early.
Do these work with Home Assistant?
Yes — all five devices integrate with Home Assistant. The Zigbee ones (TRVZB, SNZB-02P) work via ZHA or Zigbee2MQTT, and the WiFi ones (S60, POW Origin, POWCT) work through the official SONOFF integration or LAN protocols.
Ready to make your home winter-ready? Browse the full smart radiator valves, temperature sensors, and power meters at RevelSmart.com — free shipping, 1-year warranty, and 30-day returns on every order.
