Home Signal test team14 September 2026Who this is for
Every energy article says the same thing. Unplug the chargers. Turn the lights off. Wash at thirty degrees.
None of them tells you what your home is actually doing, because none of them has been inside it. So we went inside five.
Five households, a metered four-socket strip and two metered plugs in each, thirty days, and a rule: the strip moves every week and we only report what the meter said.
Here is what it said.
Every energy article says the same thing. Unplug the chargers. Turn the lights off. Wash at thirty degrees.
None of them tells you what your home is actually doing, because none of them has been inside it. So we went inside five.
Five households, a metered four-socket strip and two metered plugs in each, thirty days, and a rule: the strip moves every week and we only report what the meter said.
Here is what it said.
Every energy article says the same thing. Unplug the chargers. Turn the lights off. Wash at thirty degrees.
None of them tells you what your home is actually doing, because none of them has been inside it. So we went inside five.
Five households, a metered four-socket strip and two metered plugs in each, thirty days, and a rule: the strip moves every week and we only report what the meter said.
Here is what it said.
Shelly supplied five Power Strip 4 Gen4 units and ten Plug M Gen3 plugs. We picked five households in three countries: a family of four in a house, two flats with couples, a home office, and a retired couple with a garage. Each got one strip and two plugs.
The strip went on a different group of appliances each week. The two plugs went on the appliances that stand on their own. The app logs every outlet and every plug separately, in watts and in kilowatt-hours, so at the end of thirty days we had a per-appliance number for about twenty things per home.
We did not change any habits during the test. The point was to see, not to save. The saving is what we worked out afterwards.
An eleven-year-old chest freezer in an unheated garage that gets warm in summer. 1.9 kWh a day in the test month. That is about 148 euros a year at their tariff. They had assumed a freezer was "a few euros a month".
Fix: replaced it. Payback under two years. Found by one plug in one day.
Television, soundbar, set-top box, console. 31 watts with everything off, all night, every night. About 74 euros a year for a wall nobody was watching.
Fix: the strip switches three of the four outlets off from midnight to seven. Saving about 55 euros a year. Set once, took two minutes.
A laser printer, a monitor, a desktop and a desk lamp. The printer drew 9 watts asleep and was asleep 23 hours a day. The desktop drew 4 watts "off".
Fix: printer and desktop on a schedule, off outside working hours. About 28 euros a year. Small, but free.
Both couples suspected the fridge-freezer and both were planning to replace it. A plug went on each for the month. Both were normal for their size and age.
Fix: nothing, and that is a result too. Two fridges that were fine are still in the kitchen, and nobody spent money on a new one.
Not standby. The opposite. 2.6 kWh per load, five loads a week. Around 340 euros a year. The family knew it was "expensive". They did not know it was a third of their bill.
Fix: none from a plug, except knowing. They now dry outside when they can. The number did what no article could.
Five homes, five different answers. Not one of them was the thing the household had guessed. That is the argument for a meter over a tip.
Two of the five homes have electric water heating, and one has an electric hob. Neither the strip nor the plugs can see any of it, because none of it plugs into a socket. Shelly says this on the product page and we will say it here: this is a socket meter. If your question is about a water heater or a heat pump, you need a meter in the consumer unit, which is a different product and an electrician's job.
What the strip and the plugs do see is most of the small stuff and all of the standby, and across our five homes that was 231 euros a year of things that could be cut without anyone noticing.
Nothing in the kit is wired. The strip and the plugs go into ordinary sockets. Joining them to your Wi-Fi happens in the app, and that step is where the negative reviews on Shelly's store concentrate, so do not rush it.
Each outlet is a line. You name it, you see watts live and kilowatt-hours over the day, week and month, and you set a schedule per outlet. There is no subscription and it works on the local network, so it also plugs into Home Assistant if that is your thing. Two of our testers had it in Home Assistant inside ten minutes.
The one complaint, echoed in the reviews on Shelly's store: the strip reports a small draw on an outlet that is switched off. It is the strip's own electronics, about half a watt per outlet. Harmless, but confusing until you know.
The kit we tested, at the test price
Cheaper, and it meters one thing with no app and no switch. You read a number off a tiny screen and then you do nothing about it, because it cannot do anything. Fine for one question. Not a way to run a home.
Sees everything, and tells you nothing about which thing. One total, the same as the bill, only live. Excellent for the wired loads. Useless for finding the freezer.
Nearly the same thing as the strip and a valid choice. You lose the single housing and gain the ability to spread them around the house. That is why the kit we tested is both: the strip for the media wall and two plugs for the appliances that stand on their own.
The test, in numbers
The Power Strip 4 meters four things at once and switches each one off on its own. The two Plug M go on the two appliances you are not sure about, like the freezer in the cellar or the dehumidifier. Together 74.90 EUR against 79.80 bought separately.
Plugs meter what plugs into them; a hardwired water heater, hob or oven is not visible to them.
"Finally got full control and power monitoring for all my appliances. Seamless Home Assistant integration with local control out of the box. Great dashboards, detailed energy flow data, useful automations, and precise metrics to make informed decisions."
"Great useful product for controlling, monitoring and customizing your appliances."
"excellent to track the consumption. the app is very intuitive!"
"Delivers as advertised. Unfortunately the indication light can't be turned off without turning off the device -1 star"
"Excellent pack. I'm using one peace for scheduling the irrigation pump at our cottage house, one as switch off timer for a steam iron and one for monitoring a breadmaker."
"Nice design, good features and easy configurability. Unknown if the switch knobs are moist resistant, unknown if the relays are dual pole ..."
Four stars and below are left in. The most common small complaint about the plugs is the status light, which cannot be switched off on its own. The most common one about the strip is a small reading on an outlet that is off, which is the strip's own electronics.