It’s good to take a mindful approach to your energy use. The good news for smart home fans is this area of tech is made with low energy consumption in mind.
One of the hidden innovations of smart security cameras and smart speakers is in making always-active devices that barely use any power much of the time.
For example, the power a 1000W microwave can use in ten minutes would keep an Apple HomePod Mini going for up to two weeks.
We’re going to go a little deeper in this look at smart home energy consumption. We will show you how much smart speakers, cameras and lights really use, with the help of a power meter.
Plug a device’s power adapter into one of these and it tells you how much energy it draws from your supply.
A quick note on jargon
First, let’s deal with a few terms.
We’re going to give you the wattage of each product. However, to square this with the bill you get from your energy supplier we also need to deal with the “kilowatt hour”.
This is what you get when you divide the wattage figure by 1000. It’s a measure of energy use over time.
Check your most recent energy bill or sign into your supplier online to find out how much you pay per kWh. To calculate our cost sums, we’ve used a figure of 14 cents per kWh for figures.
Calculating the cost of a smart home
No lone smart home product uses much energy, as you'll see when you dig into the calculations below. But what if we put together a little simulated smart home? Let’s say one with an Amazon Echo, two Echo Dots and a Sonos One.
Plus four Philips Hue smart bulbs that’ll be used four hours a day at maximum brightness.
Throw in a Logitech Circle 2 smart security camera for good measure. How much would that cost in a year?
A rough calculation says the Echo uses around 26kWh, the Dots about 21.9kWh a piece. The Sonos? 33kWh based on 10 hours of listeninga month. The Hue bulbs will use around 9kWh each. And the Logi Circle 13kWh.
Add that all up and you get 151.8kWh. And on the average US power deal, that equates to around $21 worth of power.
That’s not too much for a year’s worth of music, lighting, security and, if you really get into Alexa, conversation, right?
Smart speakers energy use and cost
How much power do always-on, always-listening smart speakers like the Echo use? We tested out a bunch of them, while in standby and playing music at various volumes to find out.
Apple HomePod Mini
Year of standby cost: $0.6
The HomePod Mini is an extremely efficient little speaker that uses little power whether it’s in standby or playing music near its maximum volume. When not playing it uses 0.8-1W of power, and after a while it enters an ultra-low power sleep mode that consumes around 0.5W.
We’ve read this should happen after eight minutes, but it took significantly longer in our testing. No biggie, considering we’re talking about low power use in both states.
Its power consumption only raises a little when you play music at a low volume, to a rough average of 2W. We used the sort of level we might choose to listen while working.
At high volumes the HomePod Mini draws around 8W, but the speaker sounds at its best at slightly lower levels. Maxed-out you can hear the compromise of the small drivers a little.
Google Nest Audio
Year of standby cost: $1.71
Google’s Nest Audio uses passive radiators to provide its low-end power, removing the need for a more powerful bass amplifier. It leads to fairly low power use regardless of the volume of your tunes, although consumption is higher than the HomePod Mini’s in all situations.
The Nest Audio draws 1.4W when sitting around waiting for a voice command, lower than the Amazon Echo devices tested.
Power consumption is around 3.5W at moderate volumes, the kind you might use when just putting on some background music.
This raises to 13W at high volumes, similar to the Sonos One. Which gets you better quality per watt? The Sonos.
Amazon Echo Studio
Year of standby cost: Up to $7.48
The Echo Studio is Amazon’s most powerful smart speaker, and its energy use is pretty much in-line with that status. A
ccording to Amazon’s own documentation it should use 3-3.6W depending on if the microphones are switched on or not. However, even after leaving it sat doing nothing for a couple of hours our power meter still registered 5.6-6.1W power draw.
This suggests the amplifier circuitry is still active in standby, at least with the software version available during testing. Predictably, then, power consumption does not actually rise that much when playing music at low level volumes, to around 6-7W.
Power use varies a lot more than in most rivals at high volumes because the Echo Studio has an active subwoofer driver, rather than passive bass radiators. Big bass booms mean more power is needed, and we recorded peaks of 45W at high volumes.
However, do remember this is a very loud speaker, with peak volumes greater than most. It’ll make your neighbours angry within minutes. That draw is not consistent either. It’s significantly lower most of the time.
Amazon Echo
Year of standby cost: $3.67
Amazon’s own estimates of 3W for the Echo’s power consumption are pretty much perfect. It uses 3W when just hanging around listening out for the Alexa wake word.
Use a Skill like the Golden Ticket movie trivia game and that only bumps up consumption to 4W. Play Spotify at max volume and the average power use is around 6.6W.
The Google Home claims to use just 2W in standby, although this will only save you about $1 over a year. However, if your house is full of Echos, bear in mind they are constantly sipping juice at about the rate of a lower-power LED lightbulb.
Amazon Echo Dot
1.7-3W standby
3W Spotify at max volume
Year of standby cost: $3.67
You might expect the Echo Dot, as a smaller unit, to use a lot less power than the full-size Echo.
In standby we found it seems to meander between about 1.7W and 3W power drain. Given at this point it’s doing exactly what the larger Echo does, we’re actually surprised to see those consumption dips.
Play music through the Echo Dot using Spotify and it stays around the 3W mark. This is because the puck has a pretty weak amplifier and speaker. However, it’s a little strange to think it’s using a similar amount of power whether it’s actively doing something or not.
Sonos One
3.5-4W standby
5.6W 25% volume
11.2W at 80% volume
Year of use on standby: $4.94100 hours at 80% volume: 15c
The Sonos One uses 3.5-4W in standby, which is relatively high if you only use your Sonos every now and then.
Use it every day? No problem, as it shouldn’t cost you more than $4.94 a year.
We’d argue the Sonos One can be used as a main music source if you’re not a sound obsessive.
It sounds great to us. Even at 80%, it only uses 11.2W. That at a volume that’ll make your neighbors dislike you.
Smart lights cost to use
With smart lights, standby seems to be negligible so we decided to test out Hue bulbs with varying brightnesses and colours to see the difference in power and energy costs.
Philip Hue smart light bulb (Zigbee)
Year of 24/7 use at max brightness: $7.47Two hours a day for a year: 61c
Philips Hue made smart lights mainstream. Its bulbs are also one of the very best bits of home tech to show off – “Look at my pink-lit living room” and so on.
We tried one of its color bulbs plugged into a short plug-mounted fixture, so we could use our electricity meter. While it registers zero power when simply plugged in (Philips says standby is 0.2W max), the power consumption in use varies quite a bit depending on the colour.
Cool blueish-white uses the most, at 6.1W with the brightness maxed. Standard warm white uses just 1.7W at 50 per cent brightness. You could leave that on all year and it’d barely add to your electricity bill.
Philips Hue Bridge
Year of standby: $1.86
The Philips Hue Bridge is what communicates between your phone and your Hue lightbulbs. The Bridge uses very little power, with a consistent draw of 1.5W. Even when it’s left on all day and night for a year, it’ll only cost around $1.60 to power.
This is one of the lower-cost smart devices to keep operational, although of course the real power draw comes from the bulbs themselves.
LIFX+ 1100 Lumen smart light bulb (Wi-Fi)
Year of use at max brightness: $14.33Two hours a day for a year cost: $1.34
LIFX bulbs are a little different to Philips Hue ones as Wi-Fi is built into the bulb; there's no need for a hub. Our initial worry was that they would suck up a small amount of juice 24/7, which would add up over a year if you have a bunch of LIFX bulbs.
However, on standby each only uses around 0.3W, often as little as 0.2W: just a third to a fifth the consumption of a Hue Bridge.
The big LIFX+ bulb appears to use significantly more power than a Hue bulb when lit. But that’s because it’s brighter too. It’s rated at 1100 lumen, and is better at lighting larger rooms than a Hue bulb.
There is a real power difference within the range because even the smaller LIFX Mini (800 Lumen) uses a little more power than a Hue bulb. However, unless the lights are going to be on all day long, the cost difference over a year is fairly small.
LIFX Mini 800 Lumen
Year of use at max brightness: $10.54Two hours a day for a year cost: $1.24
Smart security cameras electricity use cost
Security camera power usage will vary depending on whether or not they're actually recording and if they include features like motion sensing and two way talk.
Logitech Circle 2
Year of 24/7 use: $1.96
The Logi Circle 2 is the least power-hungry security camera we’ve tested for power consumption. It uses just 1.6W when monitoring your house for movement, which creeps up to a max of about 1.9W when you use the Live View feature and start messing around, talking through the camera.
This will cost you around$1.68 to run for a year. Not much.
Hive Camera
2.2W standby motion sensing2.5W Live view
Year of use: $2.69
The Hive Camera doesn’t use cloud storage, so if someone breaks in and nabs the microSD card, you’re stuffed.
However, it does have essentials like live streaming to your phone. When simply monitoring it uses 2.2W of power, putting it higher than the Logi option in terms of energy use.
This maxes out at around 2.5W during moments when you use the live view.
Wi-Fi Mesh Systems energy consumption
If you're moving into intermediate smart home owner territory with lots of devices in different rooms, you might want to invest in a Wi-Fi mesh system.
The Netgear that we tested, though, actually had the highest power consumption of all the products we tested with the power meter.
Netgear Orbi
Year of use: $8.08
Wi-Fi issues in homes can be a real headache. The Netgear Orbi is one system that can fix all that, acting as a router and a mesh network to flood your home with signal.
It uses a fair bit more power than some smart devices when doing so, though, using around 6.6W of power in general use, per unit.
Use an Orbi and two satellites and you’re looking at power consumption of up to $21 a year, although we’ve had times where we’d pay that several times over just to get good Wi-Fi signal.
Streaming sticks and boxes cost
You might be aware of how much power your TV guzzles up, but what about the extra boxes and streaming sticks that get you smart TV apps and games?
Again, these tend to be low power but if you've got more than one add-on, it could start to add up.
Apple TV 4K
Year of standby cost: $1.70
The power use of an Apple TV 4K box is largely trivial compared to the energy used by your TV. Our power meter says it draws between 1.2W and 1.5W when in standby, similar to other low-power smart gadgets.
Apple’s highly efficient processors also keep energy use down while you do other things. Maximumpower draw happens at predictable times, such as when you play demanding games through Apple Arcade, or stream high-quality 4K HDR video.
At these points you’re looking at around 6W of power use. An Apple TV is a far more power-efficient way to stream media than a PS5 or Xbox Series console.
Roku Streaming Stick
Year of use cost: $2.38
A basic streaming stick like those from Roku and Amazon are so low power that they can run off of the USB port on the back of your TV.
We barely noticed any difference whether the Stick was sitting there idling or streaming video from iPlayer. Sat on the interface it uses 2.1W. Streaming a show it uses 2.2W.
However, don’t forget your TV will use loads more power to light up its screen. Our 55-inch Panasonic plasma TV uses 160W-300W, for example.
Nvidia Shield TV
Year of standby: $1.86100 hours of Real Racing: 10.5c
The Nvidia Shield TV is one of the most powerful smart TV boxes and it runs Android TV, giving you access to the Google Assistant AI
Play a game like Real Racing and you’ll see the power use reach highs of around 7.6W. Just browsing around the interface just uses 3W, though.
And, perhaps because this is designed as a TV set top box from the ground up, the standby mode is particularly power-frugal. A standby that consumes just 1.5W of power beats just about all rivals.
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