Recently while browsing a BMW i3 forum, I spotted the image you see above taken with an infrared thermal-imaging camera. It shows the pattern of the heating elements within a heated seat, so I figured I’d show you all what these things look like inside, and how it all works.
The photographer, Kurt Edelbach, shot these pictures of his BMW i3’s driver’s seat and posted them to a BMW i3 page on Facebook.
“Seat heating pattern, taken ~20 seconds after turning on Lev 3. Lev 1 is hot enough for me,” he wrote. “Top looks like moose antlers – Designed by a Swedish engineer with a sense of humor?” Huh; I guess those do look like antlers:
Image: Kurt Edelbach
So, what exactly are we looking at, here? Well, a heated seat works in a fairly simple fashion. Anytime you send a current through a material, you get what are called “I^2R” losses. Basically, this is the internal resistance of the material (a wire or “cable” in this case) turning power into heat. If you’ve used an electric stove or a space heater or really anything else that uses a “heating element,” then you probably get the idea.
A heated seat pad is basically just some wires, carefully spaced in a felt pad that taped atop the seat cushion (just like you see above), that turn current — which you control with a switch on your HVAC panel — into warmth for your butt and back to enjoy.
The cables are made of all sorts of materials. Seat supplier Bekaert offers three different cables:
Bekinox® VN: Made from ultra-fine stainless steel microfilaments, these are the most durable on the market
Bekiflex®: Steel core with an outer layer of nickel, zinc or copper
Bekiflex® Hx: Helix cables with a hybrid structure combining a textile core and conductive wires – new –
So basically you’ve got stainless steel; steel with nickel, zinc, or copper; or a blend of a fabric and some kind of conductor.
Image: eBay (WPD)Image: Three thermisters. (Image from Digikey)
Of course, there’s more to a heated seat than just some wires embedded in a felt pad. There’s also a controller and a Negative Temperature Coefficient (NTC) thermistor (a thermistor is a device whose resistance changes as a function of temperature; the controller can detect this change in resistance to determine the seat’s temperature). The sensor company “Amphenol” has a nice PDF that describes how it all works; you can check it out here. Here’s a quote from Amphenol:
The temperature of a heated seat is measured by a NTC thermistor that is embedded between the foam pads of the seat. The thermistor monitors the seat’s temperature and feeds this information back to the controller that regulates the seat’s temperature.
The video below gives a very general ideal of the feedback loop:
So actually, what Hyundai is asking for is carbon credits for a more complex seat heating/cooling system that utilizes airflow and a Thermoelectric Device, or TED, to more efficiently heat/cool the passenger. A thermoelectric device is something I used when I helped develop the hybrid battery pack on the Jeep Wrangler JL mild hybrid; it basically uses a current to create a temperature difference between two sides of a cooling plate:
Solid state heating and cooling company Promethient explains it on the web page of its brand “Thermavelence“:
Thermoelectric Devices and the Peltier Effect
Solid state heat pumping is accomplished with a specialized semiconductor called a thermoelectric device, or “TED.” TED’s use the flow of electrons to create the Peltier Effect within the semiconductor. The Peltier Effect is created at the junction of P and N type semiconductor elements that are laminated between two ceramic plates. With the application of a voltage and the flow of current, one plate will heat and the opposing plate will cool. When the polarity of the applied voltage is reversed, the heat flow will reverse.
Here’s a YouTube video describing this type of seat heating/cooling, if you’re curious:
I found a lot more while researching for this article. For example, here’s a whole document about seat heater injuries:
Seat Heater Injuries: An Overview Seat heaters have been installed in automobiles since the 1970s. Today they are commonplace – in about 30 percent of all vehicles in the 2010 U.S. fleet. Despite their increasing ubiquity, seat heaters are not designed to any voluntary or mandatory industry standards, leading some manufacturers to set the maximum temperatures of their seat heaters in excess of human heat tolerances. Others fail to include automatic timed shutoff switches. While most occupants are able to discern when the seat heater has exceeded human limits, occupants who suffer lower body sensory deficits caused by paralysis, diabetes and neuropathy are at risk. These design flaws have resulted in severe burns to disabled vehicle occupants—a problem that has been validated by consumer complaints, the medical literature and demonstrated in testing.
If you’re extremely intrigued by heated seats and want to learn about their importance in the auto industry at large, market research and management consulting firm Lucintel has quite a deep dive here. Here’s a quote:
ADVERTISEMENT
The global automotive seat heater market is expected to reach an estimated $1.7 billion by 2030 with a CAGR of 3.6% from 2024 to 2030. The major drivers for this market are increasing vehicle production and growing demand for comfort and safety features.
The automotive seat heater market primarily uses raw materials such as heating wires made from nickel-chromium alloys, silicone or polymer-based heating pads, and various types of textiles or leather for the seat covers. Pricing varies based on the complexity of the heating elements and integration with electronic controls; basic seat heaters are relatively affordable, while advanced systems with additional features like adjustable temperature settings and quicker heating times are more expensive. Overall costs are influenced by material quality, technology, and production volume.
• Lucintel forecasts that carbon fiber meshed weave heating pads will remain larger segment over the forecast period due to its excellent strength and low-voltage heat generation capability.
• Within this market, passenger car will remain the largest segment.
Hot damn! Carbon fiber mesh weave! This, Lucintel mentions, offers a potential efficiency advantage of a traditional metal cable-style heated seat setup. Here’s what carbon fiber heating elements look like:
Antlers? Maybe. But if you look at the next element down from them, that could be the comb and beak of a cock (as in the bird of course).
ClutchAbuse
7 days ago
Heated seats along with a heated steering wheel are a godsend after a day of snowboarding.
Craig
7 days ago
I work for a faction of Amphenol, and we do nothing like this in the location I work in.
While I’m sure they do this stuff, it’s not happening at my workplace.
They do lots of electronic stuff, in a wide range of disciplines, including
stuff for the PC market, and a boatload of other applications.
I build electronic assemblies which are fitted into Northrop-Grumman F-16
fighter jets for a flight-radar system, and the facility I work in does only
Level-3 electronic assembly, meaning it must be critical-level full capability
for applications such as medical reliance or military dependance.
We test and re-test, all day long.
In other terms, everything leaving our facility must be proven.
While Amphenol-Borisch Technologies is involved with developing
and producing an awful lot of connector formats and similar for a big portion
of the electronics industry, we’re also working on building assemblies
which are used in Defense contracts.
In my time at Amphenol, and my dad’s before me, it was only industrial and aerospace electrical connectors.
Myk El
7 days ago
To any young men wondering if there’s a car they can acquire that might interest a young woman. I say yes. It’s not a bitchin’ Camaro or any sort of sports car. It’s the car with the butt warmers. At least in places where it gets cold.
PlatinumZJ
7 days ago
The Peltier Effect! I became familiar with this when shopping for a compact dehumidifier for my office. It has a bank of fins attached to that TED, which is housed (along with what appears to be a large computer fan) in a pretty light-up case. I’m not sure if it’s entirely responsible for the slight drop in humidity over the course of the day, but it does pull enough water during a work week to satisfy all of my potted plants.
I used one of those little ones in an RV for a while, and measured temp and humidity. It basically made zero difference. Unless it’s a small area without active moisture sources, it’s basically always worth it to get one of the big expensive bulky compressor-based ones. 3x the size and power draw, 10x the dehumidification.
MiniDave
7 days ago
Re: heated seat injuries. The driver’s seat in my MINI would get so hot it would feel like it was burning my legs – BMW offered a resistor that would plug into the harness to drop the temps…..the dealer checked the seats and said it was within specs. The seats heaters had three settings, on low it would burn me – no idea what it would have done on high – fry eggs?
That said, I do like having them on cold winter mornings – the ones in our 2004 Audi had 6 settings, they were the most comfortable seats I’ve ever driven….on low it was a nice gentle warmth that really felt nice on my back!
Last edited 7 days ago by MiniDave
Balloondoggle
8 days ago
Given that pattern, I’d have to name my car Bullwinkle.
I love seat heaters, and sometimes it can even replace the cabin heat which I appreciate in an EV, but you still need to be able to clear the windshield. I’ve always wondered why you can put a defroster element in a rear window, but you never see anything similar in a windshield? Once upon a time you could find the radio antenna wire in the windshield, but that’s about as far as I’ve ever seen it go. I suppose no one really wants to look through a grid while driving, but surely with materials technology there’s a way to heat a glass panel without visible means?
Ford did offer the Quick Defrost® electric defroster for the front windscreen in 1974 on selected Ford and Lincoln models. One guy in the owner’s forum had described this technology very thoroughly.
This technology hasn’t been abandoned: you can find the list of current models with electric defroster.
When I was in Scotland back in ’97, my company leased a Ford Mondeo for me. It had exactly what you describe, a very fine mesh in the windshield as part of the defroster. It wasn’t super fast at defrosting (probably to avoid cracking the glass from thermal shock), but was definitely faster than blowing warm air at the base of the windshield like US cars do. My guess is that US regulations prevent similar systems here.
Land Rover Discovery II had it as an option. The windshield had thin, wavy, vertical wires. It was really cool until you needed to replace the windshield…
My 2022 VW ID4 has a a front windshield has a defroster. Cant see the lines like you can on back windows, so not sure how exactly it works, but it has a separate button for it from the normal front defogger.
The Nissan Ariya has a heated windshield. Can’t find any detail from a quick google as to how it works.
Slow Joe Crow
8 days ago
My 74 Volvo was built with heated seats, but they stopped working around 1976 and I first drove it in 1981 so I missed out. I’ve never had another car with heated seats but I live in Oregon so I don’t get the extreme cold of the Upper Midwest or Canada. Heated motorcycle grips would be nice and some BMW motorcycles have heated seats. my BMW just has toe warmers.
Mikko Merentie
8 days ago
Finnish car magazine Tekniikan Maailma used to include thermal pictures of each cars heated seats, heated mirrors and rear defroster in their car comparison articles. Easy way to see which car has best heated seats etc.
Ah, Jack Kirby! I met him when he showed up unannounced at one of the science fiction and fantasy fairs in the 1980s. He was so incognito there, but I spotted him and asked him discreetly for the autograph. Really nice guy!
Last edited 8 days ago by EricTheViking
Cheap Bastard
8 days ago
So actually, what Hyundai is asking for is carbon credits for a more complex seat heating/cooling system that utilizes airflow and a Thermoelectric Device, or TED, to more efficiently heat/cool the passenger.
IS it more efficient though? Peltier (TED) coolers are notoriously inefficient, usually around 5%, which is far less than a decent compressor based A/C unit.
Dunno about heating but resistive heating is ~100% so it’s hard to see how the Peltier can beat that.
Peltiers have lousy efficiency for *cooling* things, but like all heat pumps are in a sense “over unity” at generating heat. You get all of the heat you’re pulling out of the cold side, *plus* all of the waste heat generated by inefficiency. So as long as the cold side has somewhere isolated to pull energy from, the hot side will be hotter than a purely resistive heater of the same wattage.
One problem: a peltier device is going to be dumping heat or cold into the rest of the car in order to cool or heat the seat, which is going to increase the load on the rest of the climate control system. If the peltier isn’t in the seat itself then it’s just a wildly inefficient air conditioner. Compressor-based heat pumps are far more efficient.
That problem alone is a deal breaker. Besides is it THAT hard to add HVAC ducts to the seats? It’s probably a lot cheaper than the peltiers, electronics and wiring too.
I used to work in a lab where we used Peltiers to precisely control the temperature of semiconductor lasers. By controlling the temperature and current of the laser one can map and control the precise frequency (color) of the emission. Sure 670.8765nm is a whole lot like 670.8796 nm by eye but we used those lasers for hyper fine atomic spectroscopy and in that application those subtle differences make ALL the difference.
The point is a Peltier was pretty much the only tool to do that kind of work. Precise, nearly instant and very controllable temperatures for very small things are what Peltiers are best at. Large scale, not very precise cooling? Not so much.
Yep, that’s kind of the thrust of the video too. In specific situations peltiers are great, but for most general purpose things they’re a bad fit.
IanGTCS
8 days ago
I love heated seats. Once it gets below about 10 I turn them on when I get into the car. Maybe just for a few minutes but it’s nice. Once winter really hits they get a lot of use on low. Also great if I’ve been standing for a long time and my back is getting achy.
Wife’s new car that we are picking up this Saturday has a heated steering wheel too. Love it on the trucks at work, I’m sure she will enjoy it.
I love the therapeutic value of the seat heater on my back when it gets stiff. I’ve been known to seek out traffic jams or take the scenic route just to spend a little more time with it.
It’s definately great for a sore back or hips. If it’s not too hot out, I’ll sometimes run them with the AC going so I can crank them up to level 3 and really work out the tightness.
Totally not a robot
8 days ago
I was always careful about overusing the seat heaters during long road trips in my old car. The heaters were mighty comfortable, but I also found that they activated certain muscles that had me frantically searching for an exit with a nearby restroom.
Goblin
8 days ago
Cooled seats are probably the best car invention this side of car AC, and anyone who perfects the technology deserves all the credits they can get. Heated seats are also a great thing, but cooled ones are a game changer. Despite sounding like the gimmickiest of gimmicks.
Heated seats are nice, but I can take or leave them, because I wear pants. But a heated steering wheel? That’s the game changer. I’d rather not wear hand pants (or “gloves” if you prefer) if I dont have to.
My ex’s 2016 Kia Soul had a heated steering wheel and I liked I very occasionally drove it in the cold.
The seats had a cooling function that blew ambient air up through many holes in the leather. I LOVED the seats and referred to it as “ass-blow” technology.
I’m surprised ass-blow attachments never became an aftermarket thing for Aeron chairs, since part of their sales pitch is the air-permeable mesh seat fabric.
Another reason why touchscreens suck. And yes, highest trim level is typical, unfortunately. But if I’m headed that direction anyway and its optional, I’ll take that option every time.
Amen to this. I live in new england, and even I could take or leave heated seats, but man, cooled seats are niiiiiiice. I do not have a vehicle with them, unfortunately, but I really enjoy them when I borrow or rent. I get that the heater is easier/cheaper to implement, but jeez, all I want is the ventilation. Especially on long drives.
My truck has cooled seats, but my wife’s car doesn’t. She couldn’t remember what the setting was called to turn them off, so she asked me how to turn off the “butt air.”
Chris B
8 days ago
Great article. This is sorta the start of semiconductor cooling for dummies.
Jatkat
8 days ago
The energy savings from heated seats even with a conventional system can be immense in an EV. If I “tough” it out on my morning commute with my heated seats and steering wheel rather than running the resistive coolant heater in my Volt I can save quite a few miles of range, and that’s just one way!
Agree, but I still end up needing the defroster so it’s kind of a wash. If the weather is such that I can get away with just the seat heater, then it’s guaranteed that the window will fog/frost and I’ll need to fire that thing up anyway.
Highland Green Miata
8 days ago
Heated seats are basically low heat toaster wires inside your seat. Great for keeping a pizza warm!
JunkerDave
8 days ago
Heated seats baffle me. I can see the attraction for people who wear short skirts and apply thin underwear directly to seat, but I look terrible in a short skirt. Maybe I’ve just got enough lard in my butt so that cold seats are not an issue when wearing trousers. (If it’s cold enough to need a heated seat, why aren’t you wearing trousers?) True, I live in the northern US, and not northern Canada (where even the polar bears wear down parkas).
I’ll tell you there’s nothing quite like the warm embrace of a good heated seat when the rest of the cabin hasn’t warmed up and its -30C. Like being tucked under the covers on a cold night.
I’ve had many cars without heated seats and while it’s manageable, life is much more comfortable with them here near the arctic circle, especially when I’m mostly driving wearing light clothing. My current car also has heated steering wheel, another great option I didn’t know I needed.
Last edited 7 days ago by Mikko Merentie
V10omous
8 days ago
leading some manufacturers to set the maximum temperatures of their seat heaters in excess of human heat tolerances
I wish I had a car like this instead of ones that barely manage to warm you on a 0 degree day. The pendulum has swung too far the other way.
I do, but that one doesn’t come out on days where heated seats are necessary.
Sklooner
8 days ago
Living in northern Alberta these things are great- when they work, my V70 had a short and ended up burning a hole in my pants once, I was able to just solder a wire to bypass the area until I got a new seat base. My Saab 900 though the seat heaters decided to work all the time driving it in summer I pulled a fuse only to discover it shared a circuit with some vital part of the engine, 40c and the black leather seats are roasting me from underneath too
Cars? I've owned a few
8 days ago
Fascinating photos and discussion, David.
I always thought it would look more like the back window defroster wires.
I have had a couple of cars with the heated seats, and they are nice.
A heated steering wheel is the chef’s kiss. My ex-wife’s BMW X5 had that when we married. And when we replaced it with an Acura MDX during the summer, she later mentioned on the first cool day of fall that she missed that feature. I went into the manual and found that it also had that feature. She was surprisingly thankful. In her defense, the switch for it was kind of hidden behind the steering wheel itself.
I spent a little time pondering how they pass enough current to heat the rim through a constantly rotating mechanism for the life of a car, but I didn’t lose sleep over it.
The MDX also had “cooling” seats, but they were just fans moving air through the perforated upholstery and were audible when working hard. It’s like one of those “what’s that new noise” moments when I got in the car after she had been driving it.
The device is the clock spring, allows the cables for horn, airbag buttons, heat etc.. to rotate back and forth. Google it, they’re a neat thing. Can be a real ass pain to replace though
Michael Beranek
8 days ago
I’ve only had one car with heated seats, my current one. I only use it on the coldest mornings, and then only for a few minutes. I’m not really into butt-crack prickly heats.
My current car has the seat and seat back on separate circuits. So I can get a nice warm back without issues down below. Great when the back muscles are a little cranky.
Fuzzyweis
8 days ago
This is one of the best things added to cars, having just basic front heaters in my Bolt has made me a believer, and heated steering wheel, even in our mild winters here in NC they are so cozy. Could just be my old bones appreciate them more now. Next car we’re thinking may get the full massaging deal.
I’ve never had massaging seats, but I appreciate my heated/ventilated seats. I’m a bigger fan of the ventilation than the heating, but I find I get use out of both. I also suspect the heating may be something I appreciate more now than when I was younger.
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Antlers? Maybe. But if you look at the next element down from them, that could be the comb and beak of a cock (as in the bird of course).
Heated seats along with a heated steering wheel are a godsend after a day of snowboarding.
I work for a faction of Amphenol, and we do nothing like this in the location I work in.
While I’m sure they do this stuff, it’s not happening at my workplace.
They do lots of electronic stuff, in a wide range of disciplines, including
stuff for the PC market, and a boatload of other applications.
I build electronic assemblies which are fitted into Northrop-Grumman F-16
fighter jets for a flight-radar system, and the facility I work in does only
Level-3 electronic assembly, meaning it must be critical-level full capability
for applications such as medical reliance or military dependance.
We test and re-test, all day long.
In other terms, everything leaving our facility must be proven.
While Amphenol-Borisch Technologies is involved with developing
and producing an awful lot of connector formats and similar for a big portion
of the electronics industry, we’re also working on building assemblies
which are used in Defense contracts.
In my time at Amphenol, and my dad’s before me, it was only industrial and aerospace electrical connectors.
To any young men wondering if there’s a car they can acquire that might interest a young woman. I say yes. It’s not a bitchin’ Camaro or any sort of sports car. It’s the car with the butt warmers. At least in places where it gets cold.
The Peltier Effect! I became familiar with this when shopping for a compact dehumidifier for my office. It has a bank of fins attached to that TED, which is housed (along with what appears to be a large computer fan) in a pretty light-up case. I’m not sure if it’s entirely responsible for the slight drop in humidity over the course of the day, but it does pull enough water during a work week to satisfy all of my potted plants.
I used one of those little ones in an RV for a while, and measured temp and humidity. It basically made zero difference. Unless it’s a small area without active moisture sources, it’s basically always worth it to get one of the big expensive bulky compressor-based ones. 3x the size and power draw, 10x the dehumidification.
Re: heated seat injuries. The driver’s seat in my MINI would get so hot it would feel like it was burning my legs – BMW offered a resistor that would plug into the harness to drop the temps…..the dealer checked the seats and said it was within specs. The seats heaters had three settings, on low it would burn me – no idea what it would have done on high – fry eggs?
That said, I do like having them on cold winter mornings – the ones in our 2004 Audi had 6 settings, they were the most comfortable seats I’ve ever driven….on low it was a nice gentle warmth that really felt nice on my back!
Given that pattern, I’d have to name my car Bullwinkle.
I love seat heaters, and sometimes it can even replace the cabin heat which I appreciate in an EV, but you still need to be able to clear the windshield. I’ve always wondered why you can put a defroster element in a rear window, but you never see anything similar in a windshield? Once upon a time you could find the radio antenna wire in the windshield, but that’s about as far as I’ve ever seen it go. I suppose no one really wants to look through a grid while driving, but surely with materials technology there’s a way to heat a glass panel without visible means?
Ford did offer the Quick Defrost® electric defroster for the front windscreen in 1974 on selected Ford and Lincoln models. One guy in the owner’s forum had described this technology very thoroughly.
This technology hasn’t been abandoned: you can find the list of current models with electric defroster.
Very cool, thanks for the links. I suppose I’ll need to start buying lottery tickets in order to get one of those.
When I was in Scotland back in ’97, my company leased a Ford Mondeo for me. It had exactly what you describe, a very fine mesh in the windshield as part of the defroster. It wasn’t super fast at defrosting (probably to avoid cracking the glass from thermal shock), but was definitely faster than blowing warm air at the base of the windshield like US cars do. My guess is that US regulations prevent similar systems here.
Land Rover Discovery II had it as an option. The windshield had thin, wavy, vertical wires. It was really cool until you needed to replace the windshield…
My 2022 VW ID4 has a a front windshield has a defroster. Cant see the lines like you can on back windows, so not sure how exactly it works, but it has a separate button for it from the normal front defogger.
Rented a ’24 Ford Puma in England recently. It has the fine mesh defroster in the ‘windscreen’. Has a separate button to turn it on. Worked well.
The Nissan Ariya has a heated windshield. Can’t find any detail from a quick google as to how it works.
My 74 Volvo was built with heated seats, but they stopped working around 1976 and I first drove it in 1981 so I missed out. I’ve never had another car with heated seats but I live in Oregon so I don’t get the extreme cold of the Upper Midwest or Canada. Heated motorcycle grips would be nice and some BMW motorcycles have heated seats. my BMW just has toe warmers.
Finnish car magazine Tekniikan Maailma used to include thermal pictures of each cars heated seats, heated mirrors and rear defroster in their car comparison articles. Easy way to see which car has best heated seats etc.
Designed by Jack Kirby. By the looks of it.
(Ask Jason, DT)
Ah, Jack Kirby! I met him when he showed up unannounced at one of the science fiction and fantasy fairs in the 1980s. He was so incognito there, but I spotted him and asked him discreetly for the autograph. Really nice guy!
So actually, what Hyundai is asking for is carbon credits for a more complex seat heating/cooling system that utilizes airflow and a Thermoelectric Device, or TED, to more efficiently heat/cool the passenger.
IS it more efficient though? Peltier (TED) coolers are notoriously inefficient, usually around 5%, which is far less than a decent compressor based A/C unit.
Dunno about heating but resistive heating is ~100% so it’s hard to see how the Peltier can beat that.
Peltiers have lousy efficiency for *cooling* things, but like all heat pumps are in a sense “over unity” at generating heat. You get all of the heat you’re pulling out of the cold side, *plus* all of the waste heat generated by inefficiency. So as long as the cold side has somewhere isolated to pull energy from, the hot side will be hotter than a purely resistive heater of the same wattage.
I suppose. I imagine such heating gains will not outweigh the cooling losses compared to a compressor based heat pump though.
Relevant Technology Connections video: https://youtu.be/CnMRePtHMZY?si=IxjDluY6lgLGZTFl
One problem: a peltier device is going to be dumping heat or cold into the rest of the car in order to cool or heat the seat, which is going to increase the load on the rest of the climate control system. If the peltier isn’t in the seat itself then it’s just a wildly inefficient air conditioner. Compressor-based heat pumps are far more efficient.
That problem alone is a deal breaker. Besides is it THAT hard to add HVAC ducts to the seats? It’s probably a lot cheaper than the peltiers, electronics and wiring too.
I used to work in a lab where we used Peltiers to precisely control the temperature of semiconductor lasers. By controlling the temperature and current of the laser one can map and control the precise frequency (color) of the emission. Sure 670.8765nm is a whole lot like 670.8796 nm by eye but we used those lasers for hyper fine atomic spectroscopy and in that application those subtle differences make ALL the difference.
The point is a Peltier was pretty much the only tool to do that kind of work. Precise, nearly instant and very controllable temperatures for very small things are what Peltiers are best at. Large scale, not very precise cooling? Not so much.
Yep, that’s kind of the thrust of the video too. In specific situations peltiers are great, but for most general purpose things they’re a bad fit.
I love heated seats. Once it gets below about 10 I turn them on when I get into the car. Maybe just for a few minutes but it’s nice. Once winter really hits they get a lot of use on low. Also great if I’ve been standing for a long time and my back is getting achy.
Wife’s new car that we are picking up this Saturday has a heated steering wheel too. Love it on the trucks at work, I’m sure she will enjoy it.
I’m going to go out on a limb and guess that you mean 10*C, rather than 10*F. Otherwise, you’re far too parsimonious with luxuries that lie at hand.
Yep, Canadian. So 50 in freedom units.
*The Units Formerly Known As Freedom
I love the therapeutic value of the seat heater on my back when it gets stiff. I’ve been known to seek out traffic jams or take the scenic route just to spend a little more time with it.
It’s definately great for a sore back or hips. If it’s not too hot out, I’ll sometimes run them with the AC going so I can crank them up to level 3 and really work out the tightness.
I was always careful about overusing the seat heaters during long road trips in my old car. The heaters were mighty comfortable, but I also found that they activated certain muscles that had me frantically searching for an exit with a nearby restroom.
Cooled seats are probably the best car invention this side of car AC, and anyone who perfects the technology deserves all the credits they can get. Heated seats are also a great thing, but cooled ones are a game changer. Despite sounding like the gimmickiest of gimmicks.
Heated seats are nice, but I can take or leave them, because I wear pants. But a heated steering wheel? That’s the game changer. I’d rather not wear hand pants (or “gloves” if you prefer) if I dont have to.
Ditto.
My ex’s 2016 Kia Soul had a heated steering wheel and I liked I very occasionally drove it in the cold.
The seats had a cooling function that blew ambient air up through many holes in the leather. I LOVED the seats and referred to it as “ass-blow” technology.
I’m surprised ass-blow attachments never became an aftermarket thing for Aeron chairs, since part of their sales pitch is the air-permeable mesh seat fabric.
Mind. Blown.
Off to the lab!
When I wear gloves I always feel like Steve McQueen in the Lemans movie.
Life is strange.
Little tough to use a touch screen with gloves on. Bury the heated steering wheel in the highest trim level. Profit. 😉
Another reason why touchscreens suck. And yes, highest trim level is typical, unfortunately. But if I’m headed that direction anyway and its optional, I’ll take that option every time.
With how expensive new cars are, I won’t buy anything new without cooled seats.
Amen to this. I live in new england, and even I could take or leave heated seats, but man, cooled seats are niiiiiiice. I do not have a vehicle with them, unfortunately, but I really enjoy them when I borrow or rent. I get that the heater is easier/cheaper to implement, but jeez, all I want is the ventilation. Especially on long drives.
My truck has cooled seats, but my wife’s car doesn’t. She couldn’t remember what the setting was called to turn them off, so she asked me how to turn off the “butt air.”
Great article. This is sorta the start of semiconductor cooling for dummies.
The energy savings from heated seats even with a conventional system can be immense in an EV. If I “tough” it out on my morning commute with my heated seats and steering wheel rather than running the resistive coolant heater in my Volt I can save quite a few miles of range, and that’s just one way!
This! Seat heater+steering wheel heater is a few hundred watts, and keeps me nice and toasty vs the couple kW that the cabin air heater takes
Agree, but I still end up needing the defroster so it’s kind of a wash. If the weather is such that I can get away with just the seat heater, then it’s guaranteed that the window will fog/frost and I’ll need to fire that thing up anyway.
Heated seats are basically low heat toaster wires inside your seat. Great for keeping a pizza warm!
Heated seats baffle me. I can see the attraction for people who wear short skirts and apply thin underwear directly to seat, but I look terrible in a short skirt. Maybe I’ve just got enough lard in my butt so that cold seats are not an issue when wearing trousers. (If it’s cold enough to need a heated seat, why aren’t you wearing trousers?) True, I live in the northern US, and not northern Canada (where even the polar bears wear down parkas).
I’ll tell you there’s nothing quite like the warm embrace of a good heated seat when the rest of the cabin hasn’t warmed up and its -30C. Like being tucked under the covers on a cold night.
Heated seats are great in my convertible where it’s just cold enough that I need a little extra warmth so I can drop the top on a cooler day.
I live in the northern Finland and let me tell you, here the heated seats are pretty much mandatory.
I’ve had many cars without heated seats and while it’s manageable, life is much more comfortable with them here near the arctic circle, especially when I’m mostly driving wearing light clothing. My current car also has heated steering wheel, another great option I didn’t know I needed.
I wish I had a car like this instead of ones that barely manage to warm you on a 0 degree day. The pendulum has swung too far the other way.
Don’t you have 8L of pure V10 heat engine?
I do, but that one doesn’t come out on days where heated seats are necessary.
Living in northern Alberta these things are great- when they work, my V70 had a short and ended up burning a hole in my pants once, I was able to just solder a wire to bypass the area until I got a new seat base. My Saab 900 though the seat heaters decided to work all the time driving it in summer I pulled a fuse only to discover it shared a circuit with some vital part of the engine, 40c and the black leather seats are roasting me from underneath too
Fascinating photos and discussion, David.
I always thought it would look more like the back window defroster wires.
I have had a couple of cars with the heated seats, and they are nice.
A heated steering wheel is the chef’s kiss. My ex-wife’s BMW X5 had that when we married. And when we replaced it with an Acura MDX during the summer, she later mentioned on the first cool day of fall that she missed that feature. I went into the manual and found that it also had that feature. She was surprisingly thankful. In her defense, the switch for it was kind of hidden behind the steering wheel itself.
I spent a little time pondering how they pass enough current to heat the rim through a constantly rotating mechanism for the life of a car, but I didn’t lose sleep over it.
The MDX also had “cooling” seats, but they were just fans moving air through the perforated upholstery and were audible when working hard. It’s like one of those “what’s that new noise” moments when I got in the car after she had been driving it.
The device is the clock spring, allows the cables for horn, airbag buttons, heat etc.. to rotate back and forth. Google it, they’re a neat thing. Can be a real ass pain to replace though
I’ve only had one car with heated seats, my current one. I only use it on the coldest mornings, and then only for a few minutes. I’m not really into butt-crack prickly heats.
Yeah, it’s nice on a winter day when I have the car started to warm up before I get in, but I turn it off once I’m actually sitting on it.
My current car has the seat and seat back on separate circuits. So I can get a nice warm back without issues down below. Great when the back muscles are a little cranky.
This is one of the best things added to cars, having just basic front heaters in my Bolt has made me a believer, and heated steering wheel, even in our mild winters here in NC they are so cozy. Could just be my old bones appreciate them more now. Next car we’re thinking may get the full massaging deal.
I’ve never had massaging seats, but I appreciate my heated/ventilated seats. I’m a bigger fan of the ventilation than the heating, but I find I get use out of both. I also suspect the heating may be something I appreciate more now than when I was younger.