A New Way To Heat People

[Leigh Christie] is a researcher at MIT, and he’s developed an interesting solution to heating people, not buildings.

His TEDx talk, “Heating Buildings is Stupid,” demonstrates the MIT SENSEable City Laboratory’s efforts to tackle energy issues. Their research focuses on finding an alternative to the staggering waste of energy used to heat large spaces. Although TED talk articles are a rarity at Hackaday, we think this idea is both simple and useful. Also, [Leigh] is the same guy who brought us the Mondo Spider a few years ago for the Burning Man exhibition. He’s a hacker.

Anyway, what is it? The system he’s devised is so simple that it’s brilliant: a person-tracking infrared heat spotlight. Using a Microsoft Kinect, the lamp follows you around and keeps the individual warm rather than the entire space. [Leigh] has grand plans for implementing what he calls “Local Heating” in large buildings to save on energy consumption, but smaller-scale implementations could prove equally beneficial for a big garage or a workshop. How much does your workspace cost to heat during the winter? Hackerspaces seem like the perfect test environment for a cobbled-together “Local Heating” system. If anyone builds one, we want to hear about it.

Check out the full TEDx talk after the break.

146 thoughts on “A New Way To Heat People

    1. It’s just an infra-red lamp. It only has so much heating capacity. And if it gets too hot, move out of the way of the beam. If it starts chasing you, Bugs Bunny style, then just walk further away and bask in your knowledge of the inverse-square law.

      I think you’re thinking of microwave heating, which was, crazily, suggested for heating people, at several times in history including quite recently, I recall. The problem with that, is you don’t feel your insides cooking until it’s too late.

      There’s also the continued, multi-billion $ development of “active area denial systems”, which is replacing pepper gas and water cannons with giant microwaves. Apparently creates an “unpleasant itching” sensation. Which is possibly the best use of euphemism the US military / police have ever had! And that’s REALLY saying something!

      1. Does not running away from it kinda defeat the purpose, especially when we are talking about heating a person at work place or home, good luck getting any work done. Also, as you can see, the projected system has multiple IR lamp nodes, I am already using a 55cm high “tower” IR heater at work, having 2 or 3 of them glaring at me, would be uncomfortable to say the least, and relaxing at home, or doing work would be the last things in my mind, if that was the case, Also i did not litelarry mean cooking people, only in the sence of making them feel like being in sauna, and tearing their clothes off “cooking”.

    2. It’s not hard to avoid the problem of potentially harming people with the heat, you simply have a in-line breaker which prevents the infrared light from drawing above a certain level of heat, I say breaker because it’s re-useable so you only need to replace the faulty part and not a fuse too

      1. How about not using it all, There is a plethora of problems involved if you do not heat the building, we do so for a couple of good reasons. Mold, Moisture damage from condensation, and structural integrity giving away due to the two things i mentioned previously ring any bell? As a concept it sounds nice to just heat a person, but in most cases where a person needs to be heated indoors, it is ill advised to heat only the person, and leave the room/house cold. Why cant people think before they jump to conclusions about something being awesome, Meh, I ques the American mentality of “everything has to be green RIGHT NOW” is infections and as harmful as ever.

          1. Dehumidification is a very energy-intensive process, especially in a building that will have a steady infiltration of outside air (every time someone opens the door to enter it). It would probably end up using as much power as a conventional HVAC system (which dehumidifies via the air conditioning evaporator coils) and that would be in addition to the cost of running the IR heaters.

            In Winter, outside of tropical and subtropical climates the air is generally dry enough to require humidification to optimize indoor comfort, but that also assumes the building’s interior is being heated. A conventional HVAC system or a wood stove will heat the air in the building (wood stoves will also heat walls and objects via radiation) and that heat will conduct into the walls and objects in the room thereby keeping them above the condensation temperature (the dew point) so the added humidity isn’t a problem.

            Even relatively dry Winter air will form condensation on any surface with a temperature below the dew point (though sometimes the dew point can be well below freezing, and if the temp reaches that level the condensation will form as frost). And since this proposed IR heater won’t heat the room air or the objects in it then the walls/objects will have a much higher chance of dropping to the condensation temperature.

            Also, the condensation problem will be directly proportional to how many people occupy a given space since some amount of water vapor constantly evaporates from our skin, adding humidity to the air. It will also be a problem near kitchens, bathrooms, and spaces that contain a lot of indoor plants or a decorative fountain/waterfall, etc.

            It might be better to make the walls themselves into unfocused, low-intensity IR emitters.

  1. I see only one problem with this. Your nice and toasty, while the rest of the building is freezing. You’d need winter gloves to touch everything else in the room. I hope they plan on heating the building at least a little bit. LOL

    1. my workspace is my garage. Yeah, touching a frozen rim to remove the lug nuts with a heat lamp shining on my back won’t help my fingers out much. The problem with this system is directionality. You end up with hot and cold spots on the object being heated, It would take multiple beams to begin to tackle the problem and more lights means less efficiency. it also means more tracking systems, more complexity, more cost and more breakdowns of said system.

      1. You wouldn’t end up with hot and cold spots on a person if the beam is wide enough to cover the whole person. It would even begin to heat up stuff around the person as well, I would assume, which means that if you worked in the same spot for a while, things around you wouldn’t be so cold to touch.

        Also, as far as heating the room at least a little bit: a lot of the heat from the beam would land on non-person objects, which would then radiate their heat into the room. It wouldn’t keep the whole place toasty or anything, but would keep it from getting TOO cold, I would think.

        1. I welcome you to join me here in Finland at the heart of the winter to see how your theory crumbles. as long as said “beam” is behind you, or you block it in the slightest, your going to face the cold spot problem, also, when your out in -32 celsius, you seriously do not want to just stand around for 5 minutes, to wait for something to “maybe” heat up so you can touch it, you want to get on with what your doing, or your doing very little in a very long time.

          1. even if you needed 4 infrared lights to track and heat you in the baron cold with the distance from the light, it still couldn’t cover more than 25% of the room, that’s still 4 times as efficient, so whether you live in Finland, Canada or Iceland, it’s still going to be more efficient the world over, the point of this is to help save energy and preserve our world

      2. Adding enough lamps should give enough redundancy. The idea itself is good in principle, second only to putting another sweater on.

        Enough lamps will avoid cold spots. Perhaps they could even give them focussing capability, to size the beam to fit. Though extra lamps, pre-focussed, would be cheaper. You’d only need one central computer to control it, with possibly 2, maybe 3, camera-sensors.

        The idea of just heating people, not empty air has some merit, though it depends how much air movement there is in the room, and how cold it is. Just insulating the room would be much better, so maybe this is a solution for tents and other temporary structures, even outdoor heating.

        Overall I think, nice principle, but in practice will probably work out useless. Or very niche.

      1. IR travels in straight lines, and air is fairly transparent to it. It only becomes heat of the wasteable type, once it hits something and is absorbed. In this case, a person. The person themselves will give off heat, yes. But up until that point, there’s little wastage. Compared to typical room-heaters that heat the entire air contents of the room, not just the people.

    2. I can see it working fine — if everyone has Tony Stark’s lab. These kinds of projects just get me down, like someone is giving up. I would much rather see smart folks working on energy sources good enough that we never even think concepts like “wasting energy”. For humans to reach their potential, energy should be like water in a rain forest.

      1. Well there’s that nuclear fusion thing they’re working on…

        Apart from that, if we get usage down, the amount of energy we have will *seem* endless! Which is nearly as good, and at the moment, very possible. Much of the world, houses and vehicles, were designed with energy efficiency as the last criterion. There’s tons of potential just in insulating things. Never mind more extreme stuff, like building houses nearer to where people work, and improving transport.

        I’d bet we could at least halve the modern world’s energy usage, using existing technology, if money wasn’t an issue. At *least*.

    1. Actually I saw that proposed in a very old book, something about analog tv from 50s – 60s maybe.

      On another hand, I don’t know about how others think, but IR heating panels make me feel very uncomfortable. Ceiling placed ones seem to have a good ability to induce headaches…

      1. For pleasant warmth, they should be much, much lower power, or built into some sort of feedback loop … perhaps if the tracking lamp should use IR sensor remote temperature measuring to read your skin surface temperature and dial down the irradiation if you are already warm enough. Even better, if it could project IR image, it could warm e.g. your (cold) hands while giving your forehead a break, to avoid giving you headaches while still keeping you dexterous in chilly environment.

        And all of that is todays tech, except perhaps IR image projector, but it isn’t a show stop – the technology is very well understood and making one is basically an engineering problem, there’s at least three or four different solutions for that on my mind.

    2. just crank up the wifi.. You know tho, if he could have them mounted to a quad copter, solar powered (indoors), bolt on an arduino or 3, face tracking etc.etc.etc. he may have something. But then again with the big cold of space being the new frontier, maybe we should be altering the temperature humans function at instead like,say, zero kelvin.. mit, lol.

  2. …utterly stupid for many reasons. The range of heating is low so you don’t get heating on the right parts of your body. Typically you need a cool head and warm feet and hands. Warming extremities is important (not counting your head since most of your heat goes out from your noggin). Secondly it will heat one side of your body and only when in visible range – You’ll literally be freezing your ass off. Another factor is moisture evaporation or the lack of thereof. If you have pets this loses completely. I have two persian cats. They need to be cool when moving and cool when sleeping. One of the cats sleep on his back to make heat radiate away from his belly.

    1. how about multiple sources of heating including from thetop, as for most heat escapes from your gead wear a warm hat and go nude for the rest … will see where most heat escapes … and you say taht you need to wwarm up head but it needs to staj cool. as for moisture are you referring to absolute or realtive moisture?

      1. Upon closer examination it seems that you are right. However the chimney effect might still apply. Heat directed at your chest will warm up the air within the cavity between your clothes and your skin which will rise up to your face. Unless you casually wear a swimsuit inside…uh… i guess this scenario is unlikely lol.

      2. Approximately 30% of body heat is lost through the head. More importantly, in the rest of the body, the capillaries near the surface will constrict to reduce blood flow in order to retain heat, while the head does not.

        1. If you google this fact it gets debunked? Apparently the heat loss through the meat ball is about 10%. The constriction of blood vessels in extremities is correct though since the head has a vital function. Limbs do not.

    2. Agreed, this also doesn’t do anything for cooling the building in the summertime. since you need infrastructure for the cooling system, the total cost of these things in aggregate will be more than a heat package for your preexisting cooling system.

      And these things won’t keep your pipes from freezing.

  3. Unless they’ve majorly improved this tech from the live demo at MIT last winter, I’m dubious about how well these actually work. He mentions the test they did on the steps of Lobby 7: there were three which provided a faint warmth, and tracked far too slowly/unsuccessfully to warm you against the Boston air.

    It’s a cool idea, I just hope there’s been some progress, because it was more eyesore than revolutionary in the field.

  4. Sounds like a great plan, if you stand around in an empty room that is. Better not have any tables/boxes/shelves/cabinets/other people or anything silly like that to get in the way of the heat. This has to be the least practical thing I’ve seen in a long time.

    1. Yeah, you’d need a lot of lamps. Ideally all motorised. Though you could perhaps use many many fixed ones. Infra-red lamps are pretty cheap, they’re basically incandescent lamps engineered to be even less efficient in the visible spectrum.

      Heaters are the one thing you can’t really do inefficiently. Must be a really easy life, designing heaters!

  5. This is a weird issue he’s trying to tackle.

    Firstly though, I think his plan is flawed, at least in a busy environment that is more then just a wide open space.

    If you’ve ever been sun bathing and someone walks past you, you immediately feel the cool air around you wrap around your body. The same thing will happen here, except you’ll have posts, desks, doors, water coolers, printers, people, cubical partitions etc. and that’s just in a basic office.

    Also, if you’ve ever used a infa-red heater like these, you’ll notice it doesn’t provide background warmth. That’s to say, only the side that’s facing you will feel warm. So unless the system also heats you from behind too, you’re going to be feeling very cold one sided.

    Lastly, probably the worst for most people in an office is cold feet. This system isn’t going to fix that either.

    Still, after all that I do have a few stories to tell of heating systems working as an IT tech.
    From people putting their computer towers on radiators and wondering why the computers start to crash, even though it’s ‘been fine all summer!’ to people complaining that our customer front desk was closed, turns out the 3 girls would be around the side partition warming them selfs on a radiator, talking/drinking coffee when there weren’t any customers in.

        1. They have those outdoor patio heater things, which probably are a massive crime against the environment, but anyway. You get the free-standing ones, look like lamp posts, with propane-heated emitters that radiate IR. Or a pub in town has the electric ones that look like the 500W home floodlights you can get, only they emit IR. For all the poor snoutcasts, stuck outside when they smoke. These ones are on a timer, you press a touch-sensitive button for 5 or 10 minutes heat.

          I’ve used them, they’re actually pretty warm to stand a few feet in front of. As is the point here, they don’t heat the air (which would be a losing battle outdoors), just the solid objects that they shine on. Which is pretty clever, really. Good old IR!

  6. For warehouses and other places where radiant heat is already used sure, but you typically only have radiant heating in spots where you stand for longer times. In my mind this is a solution based on limited understanding of a system and needs. For example this really makes it impossible to use organic materials indoors in colder climate due to moisture, and as anyone by a fireplace outside on a cold day knows, a good average requires searing hot on one side while you’re freezing on the other.

    Well insulated buildings with high thermal mass is so low-tech and booooring – let’s use a kinect instead. ;)

  7. Agreeing with the above comments. Nowadays houses are getting isolated better. Besides, electric heating via IR is generally uncomfortable and expensive, thats why here in Germany we generally dont use that kind of heating. Except for orphaned ducklings.
    Also, all this tracking stuff for a simple task like this is against my beliefs of the KISS-principle.
    BUT there may be other better suited applications for this. Automatic spotlight or something.

    I also don’t like the style of his talk, talking about lightbulb equivalents and all these overgeneralisations. He should stop watching bad TV shows and think more scientific. I think this is the first bad talk i saw at TEDx…

  8. In anything but the most tropical of climates, the temperature differences generated will cause the building around you to gather moisture and rot. In fact, letting a modern building drop below 15degC indoors at any time (22degC being the normal t-shirt room temperature) is a sure way to make it grow mold. Then you suddenly get problems breathing amidst all the fungi-dust.
    A word of warning to all who would try this. You can not see the particles and with some mold-species you can not even smell it. But this does not stop it from giving you an asthma.

    1. Perhaps pipes should be designed with a return-circuit, so that the hot pipe, which nearly always runs parallel to the cold, can donate some heat to the cold one to keep it from freezing. Monitor the returning water temperature, to keep it at 4 or 5 degrees.

      Perhaps with a few remote-controlled valves and some good planning, the cold pipe itself could be the return pipe. Run hot all along the hot pipe, to a point just by the sink / toilet / etc. Now and then a valve opens, here, and by the central tank, that lets it pump hot water back through the cold pipes.

      I know there’s standards on potable water having to be direct from the mains and stuff, but sure it could be managed. Many bathrooms just put a “not drinking water” sign up. A couple of UV filters could keep it sterile. It will use energy, but ultimately if it saves flood damage it might be worth it, depending on what’s likely to get damaged in a flood.

      Failing that you could run a bit of resistance wire. Which already exists, come to think of it.

      Anyway, if you’re plumbing in the Arctic, feel free to bung me a fiver. Another million-dollar idea that I can’t be bothered patenting!

      1. Actually, hot water freezes more easily supposedly (I don’t understand the science, but it has something to do with energy transitions or something?) – and besides, if you’re going to dump your hot water heat into your cold water, you’re just going to have warm water and above ambient water.

        Some people like having recirculated hot water which means the water in the lines is always hot but that gets potentially expensive not just from running a pump all the time (which isn’t so bad) but of course the obvious loss of heat throughout the system (after all, if it wasn’t losing heat in the line sitting there, you wouldn’t want to recirculate it through the hot water tank to keep it hot!).

        1. Is that true about hot water freezing quicker? Cos unless it’s something to do with dissolved gas bubbles or something, on simple principle it doesn’t make sense.

          On it’s way to freezing, hot water becomes cold water. So how can it be faster? Hotter things give off heat quicker, but once it’s as cold as “cold” water, where’s the difference?

          This is a commonly heard thing, I’d love to hear a definitive explanation.

          1. yeah, and while we are on the subject, i heard a similar thing about cold water boiling faster than hot water. i checked it out one day, it isn’t true. hot water boils sooner.

          2. >>>
            After the lecture, Erasto Mpemba asked him the question “If you take two similar containers with equal volumes of water, one at 35 °C (95 °F) and the other at 100 °C (212 °F), and put them into a freezer, the one that started at 100 °C (212 °F) freezes first. Why?”
            >>>

            So the phenomena is not talking about the difference between hot water and cold water. 95 °F is not cold. 55 °F and lower would be considered cold, and it is unlikely that 95 °F or 212 °F will freeze before 55 °F. Additionally, the article states that the phenomena is difficult to replicate due to the lack of information.

            Could it be that the cold water unknowingly contained salt which lowers the freezing point of water? This would likely cause the hot water in most cases to freeze before the colder water.

  9. Yes heating the person is perfect when heating is needed, but if a building is designed right(PassivHaus or Earthships) then none of that even matters because those require extremely small amounts of energy to no energy to keep you cool and warm. Design the building more effectively instead of retrofitting energy saving technologies on it, it’ll work better, use less energy and save more money.

  10. What if you don’t want to be heated? Do you have to run from this thing as what looks like is depicted in the third sketch? IR heaters don’t really make me feel “warm”, they make me feel like I’m being sun burned, as the heat is only on the surface of my skin or clothes and on one side. The worst is being blasted in the face with IR heat. It’s neat idea, just not very practical. And many have stated above, what about all the other objects you may have to interact with? And since all this IR heat is going to end up dumping off of people due to convection, you are sort of heating the building anyway, so maybe it won’t matter?

  11. To me, it seems easier to heat the clothing, like the battery-powered socks you can get at Walmart. This would also provide some insulation to retain the heat against the body. Radiant heat requires wearing light clothing so that the heat can penetrate to the skin, which in turn means it can also escape. Heated clothing also allows varying the amount of heat to different areas according to need.

    The problem than becomes on of delivering power to the heating elements in the clothing.This could be some kind of wireless system, which would be simpler in that it doesn’t have to track people. Or, since office workers spend most of their time at their desk, they could plug in to recharge batteries.

    But what do I know.

    1. I think the obvious solution here is clothing that is very warm and insulating, but completely transparent. To let the IR in, but not let the longer-wave IR, and conducted / convected heat out again.

      If someone can breed sheep with transparent wool, that would be a great start, ta. Failing that perhaps Polar Bears?

  12. You will be heating the buildind also. Hot people will heat the cold air sorrounding them, losing heat and needing more IR to maintain a confortable temperature… So, given enough time/people, you end with a warm building, very ineficiently.

    It’s much more eficient to wear a litle bit more clothes, and reduce building temp a few degrees C. (17-18C instead of 21C)

  13. Has this person ever lived in a cold area during winter?
    Let’s see if I can count the ways this idea has not been thought through in:
    * One-directional heating (shadowing, hot/cold spots)
    * Condensation
    * Cold environment for anything else that needs to be touched
    and the so far unmentioned privacy issue of “if the system can track me, who else can track me with the system?”

    If a room is properly isolated, heat loss will be minimal. It’s enough to have people inside to heat it up. And everyone will be comfortable.

    ;)

  14. Heat produced by electricity is stupid by default, whatever the surface to volume ratio. This IR solution means more nuke or coal industry, and I live in a country where 75% of electricity is from nuclear plants, it’s insane!

    1. I wish I did too. Nuclear (run properly) is dramatically cleaner and safer than coal. As it is, what nuclear power my country has generates huge amounts of “waste” that is stashed away despite still containing the majority of its original fissile material. All because activists who don’t actually understand the science freak out whenever anyone uses the word “radiation,” as if coal weren’t radioactive.

      1. >>>
        Nuclear (run properly) is dramatically cleaner and safer than coal.
        >>>

        Much cleaner until something goes wrong. Then it becomes a magnitude dirtier than coal and petroleum combined.

        When something goes wrong with a coal plant, it simply stops working. Likewise with a gas power plant. When something goes wrong with a nuclear power plant, the site may become unuseable for hundreds of years.

        People are right to be concerned about nuclear power. Especially given that it’s waste continues to be radioactive for over a hundred years.

        Now, if someone would design a device that turns the radiation from waste radioactive material into electricity, the material could be used to produce electricity despite it’s toxicity.

  15. I think the comment about eyes was on the money. I don’t like the at-head-level appearance of the diagram. I’m pretty sure that infrared exposure in the eyes over time can cause cataracts. I had a friend who had to have cataract surgery at a youngish age, and apparently the cause was lots of baking. Not shielding her eyes as she opened the oven “cooked” her eyes over time, something like the way egg whites cook.

  16. I live in Japan, and after seeing this talk, I apparently live in the future. This is surprising given that the country is practically still in a recession that has lasted for 20 years. Here they don’t have any centralized heating systems, a common complaint among expats alike. What they use instead is localized heating devices, some rather ingenious; I’ll get to the tech bit soon. Having lived my childhood up north, where the temperature goes way, way below freezing during the winter, it is difficult for the people here, where the climate is quite moderate, to understand what I mean when I say that I am not used to it being this cold, and that I am freezing all the time.

    Now, what they have in Japan is kotatsu. This is basically just a heater under a table, where the table is designed so that it can be covered by a blanket. As the tables are typically the type where you sit on the floor, the temperature below can get quite comfy indeed. I’ll still need to wear gloves or turn the air conditioning on not to feel cold in the parts that don’t make it below. With the price of electricity, them shutting down the nuclear reactors and all, this is not what people usually do. Typically one does wear a lot of clothes, and some even use a gas burner. Not the safest thing in the world to sleep next to a keg of kerosene. Oh, and if this is the method you use for heating, you’ll also have to open the windows every hour or so not to choke to death. Which kinda ruins the point of heating in the first place. But I digress.

    Why am I so against localized heating? You know those fancy high-tech toilets they have in Japan? They weren’t invented merely as technology for technology’s sake; I can tell you that unless you have one, during the winter your ass is going to freeze off or you’re just gonna try and hover over the bowl while doing the number two.

    1. i’m thinking a huge device, and i mean HUGE, that can heat most of the earth to a habitable climate. we should probably put it about 93 million miles away so it doesn’t cause any overheating issues or burn us up.

  17. “Their research focuses on finding an alternative to the staggering waste of energy used to heat large spaces”

    Scientists and their inability to see the big picture. This is great for large empty boxes. Useless for a home that also needs the water pipes heated, all liquids that can freeze heated, etc…

    What is better is improve insulation and stop heat losses. Make AeroGel a lot more affordable so I can fill the walls, ceiling and windows with it.

    1. Rockwool’s nearly as good, especially compared to nothing. Existing gas-filled double-glazing is good too. Conventional insulation does well in general, it’s just a matter of getting people to fit it.

      Perhaps some sort of government loan system, where the fuel you save goes to pay it off. There’s free / cheap insulation schemes in some countries, in an effort to get carbon emissions down.

  18. http://www.robertsgordon.com/content/images/GordonRayBH-main.jpg
    http://4.bp.blogspot.com/_PFCu0aiA-L0/TBkMsi0SR2I/AAAAAAAAAN8/ajV2oiZp4h8/s1600/Channel+9+News.jpg

    I encourage the speaker’s enthusiasm, but he really should have done a research paper search.

    IR heaters have been around long enough that he should have figured someone tried to intelligently focus them. Sure enough that research was done at OSU, MIT and Pitt. They discovered that it was only as effective as the room was warm….. So for small heat increases it was fine, but had serious issues if there was a large heat delta.

    The images above show traditional propane and electric IR heaters that are commonly found in industry. They either blanket the entire room with heat, or focus the heat to areas commonly occupied by humans. This is about the only way you can use such systems, because additional ‘improvements’ in efficiency simply result in other REAL WORLD problems like people feeling sick.

    Best wishes to the speaker.

    1. Same thing in practice is ceiling heaters. They work by having an IR reflective foil below the insulation, and heating cables between the reflector and the interior paneling. It’s like underfloor heating, but on the ceiling instead. It basically shines IR down at the floor and the furniture, which is supposed to make the occupants and the surfaces warm without heating the air.

      Now the problem is that the floor is still freezing cold because it immediately conducts the heat away, and any shadowed area quickly cools down just the same. That’s what makes a cold room feel cold – all the surfaces “suck” heat away from you by not returning as much heat radiation back. You can sit in e.g. a car with the heaters on at full blast blowing hot air all over the place, but it won’t actually feel warm until all the interior surfaces start to heat up.

      So you also need underfloor heating to go along with the system, and with that you’re heating the entire room like you used to.

  19. Panasonic has been marketing their Econavi units for several years now in Japan, and they get better and better each year. 2014 models can not only locate and direct air to the people in the room, but identify where their feet are (or coldest spots?) and direct air to those zones.

    1. Because a fridge will help heat the house, the compressor will generate a lot of heat. And a lot of people live in high destiny housing where they dont have a garage to keep their food.

        1. If it’s any good it doesn’t matter much if it’s outside or inside, it won’t generate a lot of heat, and on the other hand you won’t get any real benefit if you take it utside.

          1. Actually, it would benefit you a lot to put all the cold water you run from a tap into buckets, freeze the water, and then throw the iceblocks out of the door.

            Think about it. Freezing water releases 333 kJ of energy per kilogram, or 92 Watts per kilogram-hour freezing rate, and a good fridge compressor has a CoP of 5 at around the freezing point of water, which means it only uses 100 Watts for every 500 Watts of heat it pulls out while it’s freezing your water.

            Of course using a regular fridge is less optimal because it quickly collects frost and that insulates the heat exchanger and lowers the CoP, but a slight modification would allow you to extract cheap heat out of your waste water in the winter, and if you bury the ice blocks in straw – free cooling in the summer!

  20. HVAC systems aren’t just for the people. They are required to keep utilities from freezing or over heating. More importantly, buildings, such as skyscrapers, would fall apart from the expansion and contraction caused by drastically changing temperatures that normally only occur outside the structure.

  21. Heating a building is only part of the issue. You also have to maintain humidity and exchange air to maintain a comfortable environment. This means bringing in cold, dry air and exhausting existing air. As others have noted, everything else would be extremely cold. People’s skin would also be very irritated because of the dry air. That’s why there’s a humidifier on many a home furnace. On the flip side, if it’s cold and damp outside, you could end up with a humid environment inside which would mean condensation on things.

    And let’s not forget that electronics, dry goods, foods, paper products, etc., etc. are best stored under controlled environmental conditions.

    It’s a neat idea, but it neglects several factors that the HVAC industry has been dealing with for decades.

    1. Good points indeed. Have any of you ever seen what happens to a house that hasn’t been “lived in” for a while, that has had the HVAC system shut down and no climate control? They start to rot pretty damn quick depending on where you live… Heating is one thing, air exchange is quite another.

  22. We have similar “zone” heating technology already. Long John’s and our own heat. I am not quite warming up to the idea. How about freezing your other stuff in your house/workshop that shouldn’t be frozen. Nothing like sitting down in your workshop’s head and freezing your buns off while reading the shop literature. Anyways…. it will be interesting to try it in practice to see how it works out.

  23. I wonder if he has actually been in cold climate? First that sounds like a good idea, then I realized it’s not going to work, at least not in any place where it actually gets cold. You heat the building so they stay functional. IF the room is cold you can’t leave your drink, it’ll freeze. Pies have to be heated up so they dont freeze. If you breathe the moisture in your breath will build up on the icy cold walls, floor, and ceiling. You’ll end up living in a ice cave. Maybe it could work in some place whe it’s not too cold to begin with.

    1. I think it would only work as a supplemental heating system for people who want it. Run your environment on the cooler side, and anyone who is cold could use it via some tracking badge, etc.

      But really, what’s the cost savings when you run your HVAC system at, say, 63 F, and then have to install these panels everywhere for the x % of people who would feel cold?

  24. This would be awesome for pointing at my car on frosty mornings before I get into it, melting the ice off the windshield and windows and then heating the interior if it was aimed right. Saves the stinky and inefficient idling caused by starting the engine and letting it warm up which isn’t necessary for the engine unless it’s a diesel (or it’s Siberia-cold).

    And then it could be programmed to do a few sweeps of the front steps and sidewalk to melt off the ice before I step out to get in the car.

    The probable reduction in insurance costs for business owners who install one of these as a sidewalk and/or parking lot de-icer in front of their businesses would probably make it cost-effective once it’s efficacy has been proven.

    But for buildings, I’m with the better insulation/ high thermal mass/ passive solar camp. A load-bearing plastered straw bale house was by far the most comfortable place I’ve ever lived in. It was located in the southern Appalachians (still is, actually) which can get plenty hot in Summer but we never installed or needed an air conditioner. And the whole thing was heated easily by the smallest blue-flame propane heater we could find (one designed for small bathrooms).

  25. Aside from the mentioned aspects this wont reduce the energy you need.
    To keep it practical you have to use precious electricity for heating purposes.
    To deliver 1KWh of thermal energy its estimated that you need 1.1KWh of methane or 2.6KWh (!!) of electricity (just a fast research).
    For Germany the cost of a KWh of electricity lies in the range >0.22€

        1. It includes efficiency losses in the powerplant itself, because typical transmission losses are only about 7%.

          They’re simply calculating what it takes to deliver the power when electricity is produced out of a fuel similiar to methane, vs. using the fuel directly. It’s a bit disineguous because stuff like hydropower or nuclear power has no efficiency losses that matter in the first place, and electric heating can employ heat pumps which negate the loss and in some conditions produce more heat than the fuel that was used.

  26. I find it odd how on this sight people can be so critical of this guy who is just tying to share an Idea.
    Personally I would heat the floors and let the heat radiate upward and bring down the ceilings just a bit. Also if it’s a room that has many people all the time, the heating takes care of itself. Ive been in very crowded offices where the management had to turn on fans in mid winter due to the overwhelming heat generated by the people in the room.
    Now this is just a personal observation I am NOT an engineer nor do I have ANY engineering schooling.

    1. Maintaining a comfortable environment for people is not just a matter of providing local heat (or cooling). People feel most comfortable within a certain area of the psychrometric chart (i.e., a combination of temperature and relative humidity). This localized heating idea accounts for only a fraction of the variables. As you mentioned, put a lot of people in a room, and you may actually generate more heat (and humidity from breathing/sweating) than needed. In that case, you need to cool. You also need to bring in fresh air.

      An HVAC system takes into account numerous factors: the number of people, the activity they’ll be doing (office vs. a gym), other heat/cooling loads (electronics, air from leaks or people coming in/out), air exchange, building insulation, outside environment (including how much sun the windows get throughout the year), humidity (gym showers vs. an office) etc., etc. Saying, “Let’s beam heat at a person, look at all the energy we save” is like saying, “add a spoiler, all your car’s fuel efficiency problems are solved!”

  27. Large spaces means high ceilings and cold floors. The first thing to do here is move the cold not the heat. Floor fans shooting the air straight up will make a bigger difference than ceiling fans creating a draught in the middle and still not penetrating and moving that pool of cold air chilling half of the body.
    Insulation not isolation and the more the better, then worry about air quality exchanges etc.

  28. Let’s just call it what it is, DEATHRAY. Joking aside, +1 for all the comments about air exchange, freezing utilities, etc. I see this being an option in bus stop shelters, open train platforms, and things of that nature. I’ll take the jumpsuit comment 1 step further, add heating elements to the suits, and some inductive coils to the shoes. Then embed other inductive coils in the floors, so you only heat people when they are in the building. Maybe build a supercap into the jumpsuit so that it charges and discharges while you are walking around and you can take a little of the heat with you.

  29. Gimmick, nothing else.

    1. you cannot heat a person uniformly using IR, at least the underside of arms etc. would be cold, it would feel something like standing next to a black tin building in full sunshine when the air is cold, it’s a very odd feeling but not comfortable heating.

    2. IR can damage the eyes over time, look at the eye damages caused to smiths, glass blowers and other people who work a lot with heat.

    3. while the cost of the electricity would be lower than if the whole space was heated electrically the cost of all that robotic stuff is high, and maintainance is going to cost, also electricity isn’t the cheapest to heat buildings, burning large volume renewable fuel (pellets etc) is probably the cheapest viable heat source.

    In conclusion: if your goal is to actually save energy, put a couple of fans in the ceiling to rotate the air to prevent hot air from accumulating up there, and maybe turn the heat down a couple of degrees and tell anyone complaining to wear clothes.

  30. I did a thing a few years back for a Make contest for keeping warm in the winter. My idea was a battery powered vest. I used the pockets of a hunters vest that had a heating pad sewed in. Pockets on the side had battery packs and a small inverter to heat the heating pad. Canadian studies have shown that your sense of being hot and cold and blood flow to your extremeties are influenced greatly by heat loss from you core (heart, lungs etc). Keep your heart and lungs warm and your heart will pump blood to extremeties (which will not get cold) even if the air temp is cold. So the heating pad in the vest kept my core cold, enabling me to work even in cold temp.

  31. When I was a kid I had an encyclopedia that had a drawing of a guy sitting at a desk with wavy lines coming out of baseboard radiators. The caption read, “In the future, microwave radiation will heat people and not buildings.”

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