Winter has arrived, and by now most households should have moved on from incandescent bulbs, so we can’t heat ourselves that way. Avoiding the chill led [edent] to invest in an electric blanket. This isn’t any ordinary electric blanket — no, this is one connected to the Internet, powered by Alexa.
This is a project for [edent] and his wife, which complicates matters slightly due to the need for dual heating zones. Yes, dual-zone electric heating blankets exist (as do two electric blankets and sewing machines), but the real problem was finding a blanket that turned on when it was plugged in. Who would have thought a simple resistive heating element could be so complicated?
For the Internet-facing side of this project, [edent] is using a Meross smart plug and a Sonoff S20 smart plug. These are set up through to work with Alexa and configured as an ‘electric blanket’ group. Simply saying, “Alexa, switch on the electric blanket” turns on the bed.
There are a few problems in need of future improvement. Alexa doesn’t recognize voices, so saying ‘Turn on my side of the bed’ doesn’t work. The blanket also shuts off after an hour, but the plug sockets stay live. There’s also the possibility that hackers could break into this Alexa and burn down the house, but this is a device on the Internet; that sort of stuff virtually never happens.
You can check out the demo of the electric bed below.
Alexa, is my house on fire yet?
Literally the first thought upon reading the title. I can’t really think of a way to bring this within the bounds what I’d call “safe” in any meaningful sense. So many ways this could go wrong, from plain electrical to remote exploit issues.
Those Sonoff things are cheap and poorly made, the real fire risk is there I think. The blanket has an automatic shutoff (bimetalic strip maybe?) after an hour, an attacker couldn’t just make it overheat by leaving the plug on. Kind of like hacking a toaster oven into a reflow oven but leaving the bimetallic in – even if you do the control really badly the device can never get hotter than its designed to operate at normally.
Electric blankets should not be much of an issue with a Sonoff device, they are only a couple hundred watts. Really not much more than a few incandescent bulbs. It is space heaters 1kw and over that I would be concerned about running though such a device.
An internet connected electric blanket is a nice idea. You typically need to turn these things on a half hour to an hour before going to bed if you want a toasty warm bed. With it internet connected you can turn it on from another part of the house without making the trip to the bedroom, or even just schedule alexa to turn it on an hour before you typically goto sleep.
You’re trying to get me killed haha
Someone asked if you could start a fire over the internet. Dan Tentler says “challenge accepted”.
Sorry I forgot where in this talk that came up but…it’s somewhat entertaining anyway.
https://www.youtube.com/watch?v=5xJXJ9pTihM&t=1s
7:00 (not entirely suitable for work)
Here in Bush country (that’s when it happened) we have our blankies shut off after 10 hours, 2hr for heating pads. Since simple mechanical power switches have been eschewed for touch buttons, MCU’s, and LED displays, they tacked on additional timers. Of course they don’t come on again when they are disconnected by a IoT device. The old blankets worked without the control just on high. Thermostats are series connected throughout the blanket to prevent bunched up areas from overheating. Now these have been replaced with thermal fuses and the blanket just goes into the trash or to charity. Don’t get your electric blanket in a twist.
I have a 3 speed air filter that moves air out of the bathroom which has no heat so heat comes in. I would like to put it on a timer for when I am home or not, but I can’t because of the pushbutton thingie with LED display to show 1-2-3 even that runs warm when off but won’t resume operation when powered.
Internet of Idiots making laws. The obvious way to run the blanket is with a bed occupancy monitor. You want the WWW to know when and with who, no way.
Sonoff + heating element + 24/7 = big nope from me
Hmmm,
Doesn’t sound the safest thing to do. However for now this works for [edent].
Makes me wonder though when gas (methane) powered boilers go IOT?
Worst still is if the firmware parts* were in one controller controlling motors, valves, ignition, etc… that’d be like putting a literal bomb online for anyone to set off.
To be safe though the controller and IOT should stay separate so a guaranteed activate deactivate signal can only be sent to start the central heating. Same with a lot of things that could go horribly wrong if malicious people were to try targeting IOT for property damage, attempted murder of their target or public endangerment via misuse of Internet Of Cars.
Why have an electrically heated blanket?
Sounds like the house needs better insulation, and a more energy efficient heating solution instead.
Like Fiberglas/or-similar insulated walls, three glass windows, and a simple heat pump. (If the heat pump source for “warmth” is air, or geothermal, or just a coil of hose dugg into the front lawn is though a better question, but the last one gives better snow retention if one wants to be the first and last on the street to have a snow covered front lawn, then this is an option.)
Though, that is a bit of an investment….
you cant beat the energy effeciency of an electical blanket.
sure resistive heating by electricity is a factor 4 worse then gas/other modern options, but heating your hole house when you want a warn bed is more like a factor 100, so the blanket clearly wins
The blanket wins until you have to get up and take a shower in the morning.
Figuring a machine’s efficiency is a bit different when waste heat is actually the goal instead of a by-product. If heat is being lost, you could always put more blankets on top of the electric one. Pretty easy to boost that efficiency.
If you don’t need or want to heat the rest of your house, an electric blanket is a huge money saver. They only consume a couple hundred watts and will keep you toasty warm, until you need to get out of the bed. If you live in a region that gets cold, but does not get to freezing where you have to worry about pipes freezing then you can save tons of money by not running your central hear to heat parts of the house that are unused. When you wake up, turn on the central heat to heat up the house. If you have a forced air system the house will probably be at a reasonable temp in 15min or so.
I find this aricle very confusing :-)
– Summer has just arrived, so why would anyone need an electric blanket
– what is an electric blanket? In winter you just shut the windows. Sometimes.
– Ahh, that is what an electric blanket is, one of the most dangerous things you can have in a house.
– lets connect that to the well know, highly reliable, sonoff
Every time I read some article about some network connected thing, I wondering on that ultimate forcing of different absolutely useless cloud services from Big Brother. Is that some kind of joke? Or just a way to fund HaD? I have nothing against connecting devices to the network, this is fun and gives endless features. I have a lot of network connected devices at home, from BME280 sensor in Stevenson screen on the roof to washing machine and pump station. But I can’t find any reason that will lead me to let them leave local network and connect to some cloud service in the internet. What is the point with that cloud madness?
How are people not scared of putting a mains voltage device on their beds? It freaks me out enough that I’d rather just be cold.