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. Interesting idea.
    The useful aspect is that longwave IR LEDs are now cheaper to make thanks to the advances in photonic lattice technology.
    Thanks to metamaterial lenses the beam can be focussed to only heat one small area but have a “dead spot” for the person’s forehead and eyes.

  2. Not impressed by this. It’s full of holes and far from a solution. I agree that something needs to be done.
    For instance, when a surface gets cold, water is able to condense on that surface (we exhale gallons of water vapour). This leads to damp and mould. Which leads to reduced comfort and higher energy inputs. etc etc
    I suggest this guy speaks to people who work with buildings’ energy before he does his next TED talk. Disappointed with MIT. I’m sticking with insulation, smarter management and low carbon supply.

  3. Why not work on better insulation, better thermal clothing lines?
    That would be a better investment than this…

    The only usage I can see is outside, I would like a few of these in my garden for the winter!

  4. This seems like an interesting intellectual discussion, but something that would just never be practical.

    I’ll admit I haven’t looked into it in depth, but off the top of my head…

    – in any sufficiently low ceiling place, your head will get a lot more heat than your feet, increasing the required emitters
    – what about objects that block the way, or varying body positions? How do different clothing types affect this? My pants are warm on the outside, but my skin is cold because I have thick jeans on. Now my legs are freezing because I’m sitting at a desk?
    – for many reasons I can’t see how this would be in any way uniform
    – interacting with any objects in the room becomes unpleasant because they’re all cold
    – so you have to have an ambient-to-person temperature differential of maximum 10 degrees, which means that you still have conventional heating requirements and problems
    – what about the personal energy expended due to heat lost due to respiration?
    – the amount of tracking emitters required to have anything resembling a pleasant experience would require substantial cost, far in excess of heating costs for probably several decades
    – those with poorer circulation will be adversely affected
    – I really don’t want IR light (which is sufficient to warm me up) constantly beaming into my retinas
    – your cost would be _significantly_ less to just properly insulate the building and re-use waste heat from a variety of sources.

  5. Some really revolutionary techniques have already been invented. One idea is to use cost-savings IR lamps inside an air suction device in where the air is heated in a chamber by the IR waves. Then the heated air is blown out into the cold room. The lamps are controlled by timers and temperature. It heats you and the room.

    Another is a human-powered self heating vest for hikers/campers. It uses your own warm breath to heat a vest with air chambers. It works pretty good too.

    Another idea is a hot-water tube circulatory system for a full body suit. The water is heated via electrical power and pumped through the suit.

    And finally there is the Sharper Image portable heater that uses a battery-operated heater fan that heats the jugular veins in your neck. The heat is distributed throughout your body via your own circulatory system . They also made a cooling version too.


  6. While not tracking, our old workshop had 2 massive tubes across the inside of the roof, which it turned out were infrared. It seemed like a good idea, and it worked in the winter, or seemingly. Until you touched tools or cars that were still cold..

  7. Considering the fact that this focuses on just heating the person and not the building, and considering the fact that buildings must be heated in order to remain useful, I am doubtful that this system is in fact more efficient.

    For certain, the cost of electricity and energy will go down, but the cost of building maintenance and health will likely go up. To determine efficiency in a real world setting, one must consider all of the costs that go into the use of a building.

    If as some have argued, the building will develop mold and rot when it’s environment is not properly heated, then where is the efficiency in this heating system. And where is the environmental good that comes from it’s use. People working inside a sick building are not the only ones that will suffer from it’s use, the animals and the surrounding environment will suffer as well.

    It seems to me, that those who continue to argue “lower your thermostate to save energy” are delusional and barking up an imaginary tree. Why would I set my thermostate at a temperature that will lead to my becomming sick? And why would I set my thermostate at a temperature where I will be cold, uncomfortable and stressed out which ultimately will lead to me getting sick?

    Putting on more clothes does not in an of itself safegaurd a person from the ills of cold temperatures, and those who have poor health are more likely to be affected by the stress which can lead to a heart attack or stroke.

    I have no problem with people wanting to do things more efficient and safegaurd the environment. I have a huge problem whith people who try to put forth policies and inact programs that do harm to others who are less fortunate because they are just to lazy to develop a solution that works for all concerned.

    Reducing the amount of energy we use can only occur if we produce technology that uses less energy to do the same work that is already being done. In addition, there is only so much we can do in the long run to reduce energy consumption. At the same time. there is a lot more we can do to produce energy in a cleaner more efficient and abundant way. We just have to develop it.

    If you realy want to do some good regarding energy production and efficiency, develop a way to harness the cosmic energy that surounds us constantly. At this point you’re working on a solution, rather than manufacutring another man made problem which this method of heating is more likely to do.

  8. I think the speaker is right, heat people not the buildings. He gave an example of how part of this can be accomplished. As an HVAC Engineer myself many of these recommendations have been around since the 60’s. The difference now is we have almost reached the point where many of the critical technologies are available.

    For example in the last 5 years various wireless devices have provided us with cheap, low power and long range communication. Embedded computers are power efferent and have enough compute power to handle the task. Then on top of that we have advanced sensors that can now be made inexpensive enough (sub $50) to give 3D data and track items in a sizable area (say a 20’x20′ location).

    There is still 1 item that are still needed at a much lower cost – Thermal camera to determine which objects need to be heated and how.

    The idea would be to use the best heat source for the job. For example if you have an class room, then directional vents along with controllable radiant flooring could keep individuals warm in winter and cool in summer. Sure the effect won’t be instantaneous, but perhaps 1 or 2 minute lag time. For those individuals moving then the above example of radiant heat would suffice to keep you warm, if the area around is say 10 degrees cooler than what would be considered comfortable.

    Currently many building are already doing forms of this, by turning off heat/cooling to rooms not in use and preheating and pre-cooling rooms right before they are used. Then after everyone is comfortable reducing the heat/cooling. http://energy.gov/ estimates a 20% savings if general area are kept 10 degrees cooler.

    Currently the cheapest Thermal image is the FLIR ONE, which runs $149. https://www.nationalgridus.com/non_html/shared_energyeff_office.pdf states that yearly cost for energy per square foot is $1.40. To see a 5 year pay back at 15% energy savings The combined cost for all sensors and electronics would need to be under $1 per square foot. That would mean for a typical class room settings (20’x20 =400sqft) would add about $400 to the whole room. If you had 4 sensors (each corner) and any additional computing power, plus the cost of additional actuators/valves/relays you see where cost becomes the deciding factor.

    So until thermal imaging gets cheaper I think we will just see improvement in using 3d sensors to help improve occupation based controls.

    Not quite sure how this hack idea will go over but a crazy thought came to me from the people in the military industrial complex (namely DARPA). There are two directed energy weapon devices out by Raytheon called ADS II and it’s weaker cousin for LEO called Silent Guardian. These “weapons” are meant to “heat the people and not the buildings”. In theory it is supposed to heat the 1st dermis level of your skin to a very uncomfortable level so you will be forced to run away from it. Ala: crowd control.

    Well if a HaD person would take a even weaker version of Silent Guardian, still at 95 Ghz, one could put a milliwatt omnidirectional version inside a wall heater unit. Then you would have an instant warm feeling on your skin even through your clothes. Your eyes and lips would probably experience dehydration but a room humidifier could fix that. Your internal organs would be totally non-impacted, just your top-layer skin would feel the warmth. All objects in the room remain cold and unheated.

    If you wanted to get fancy then a person tracking device could aim the mini-ADS unit at the person at all times rather than omnidirectional. But all that would do would be to just heat one side of your body. A unit each in all four walls (and ceiling and/or floor) of the room would ensure full body coverage.


    Cooling is another issue all together. I recommend a personal cooling device that uses your Carotid artery as a full body cooling avenue just like the Sharper Image personal cooling system. It works quite well, however, if not properly used can cause “brain freeze” headaches (literally).

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.