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Radiant windows: Hey M.E.

of these windows for a project. I was wondering if you use the same heat loss calcs as with Radiant Floors? I also am curious about controls. Each window on it's own control could be expensive. I am very excited about this product and eager to learn everything I can.

HBR

Comments

  • k
    k Member Posts: 38
    Radiant Glass: Hey Mark

    So I look into the radiant glass, biggest problem is lack of any distribution outside of, apparently, Colorado.

    Also, not that it means anything to me., but the university testing was done by a lab that seems to specialize in turbocharging and the like...wondering if anyone more errr, direct experience has tested this stuff.

    It is something that I am seriously considering, since just insulating blinds may run me in the 10k range.

    it might be a fun thing, but I kind of need to know if this is for real or not.

    K
  • Mars_3
    Mars_3 Member Posts: 65
    Radiant windows

    K, my name is Matt R and I have worked with ME at Advanced Hydronics in the past. I have been to the manufacturing plant and have seen these windows in person. they are nothing short of amazing. I will be putting one in my own home for a master bath remodel I will be doing in the next few weeks. So I guess the short answer is yes they are for real and once they hit the open market " wow" comes to mind. BTW I manage a hydronics department here in denver for one one of the largest HVAC businesses left here.
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,852
    It's for real...

    One of the obvious problems for glass is that it is heavy, and it breaks real easy. The long term plan is to have manufacturing facilities set up all over the country to ease shipping problems.

    Distribution can be an issue outside of Colorado, but we're working on it.

    The National Gas Machine Laboratory is one of the most respected thermal testing facilities in the world. Dr,Chapman is a worldly recognized expert in thermal transfer and radiant energy. In fact, he is published many times over and a respected fellow of the ASHRAE group dealing with human comfort standards.

    If you have a better organization to which you feel would be more qualified to test a device that has no known parameters, by all means please share it with me. There are no listings for testing radiant glass heaters in the yellow pages :-)

    The biggest stumbling block for retrofit is getting adequate power to make these beauties work. If all a person is looking for is thermal opacity, then the power consumption is significantly less, ad the efficiency significantly more.

    We are still trying to round up the necessary dollars (around $10 mill) to complete our R&D and get geared up for full mass production. It seems to be getting closer, but is always just out of reach.

    I have four of these beauties in my home up in the mountains, and it feels like you are standing in the sun when you are standing in front of it, except the windows face north.

    We are going to the mountains tomorrow to commission our first full scale radiant window heated home (new construction). I will take some photo's.

    It will change the way we keep people comfortable.

    Where are you located?

    Thanks for asking.

    ME

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  • mark ransley
    mark ransley Member Posts: 155


    Do you mean Loewen and Alpen R 7, Hurd lost their **** on a similar "lifetime warranty" product, is this an off shoot?

    High R is great, what is the warranty and how do you think in 10 yrs they will pay.
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,852
    No comparison to conventional windows...

    www.rgiglass.com

    And Matt R will be one of our dealers once we swing in to production.

    ME

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  • k
    k Member Posts: 38
    re

    Thanks for replying Mark

    I mean no disrespect as to the testing, it is just my personal lack of knowledge on the subject. i would , of course, have no idea about who to send windows to for testing.

    I would like to use a bunch of it for energy reasons, not for heat per se, but it would need to be cost effective, at least to a point.

    The style of my house means that i could save at least $400 per window in thermal blinds by installing such a thing.

    I am in mass.


    One wonders if licensing at least for the glass production might be the solution. I suppose Anderson ships all over so maybe it is not ridiculous to manufacture in one location





  • Mark Eatherton
    Mark Eatherton Member Posts: 5,852
    No disrespect taken...

    hence the smiley face at the end of my sentence. It's just one of those things, and KSU did the radiant floor study for the RPA, so it seemed to be a natural place to start. We may get some help from NREL soon. But am not sure they are any more capable of testing and diagnosis than is KSU.

    We are planning on building our own environmental test chamber whereby we can simulate any and all weather conditions seen on the face of the earth. This will be necessary to access the overall potential of the product. Although the information generated by KSU is wonderful, it is only applicable to that size of window under those conditions, and we can't generate the necessary performance charts engineers and architects want to see in order to be comfortable specifying the product.

    Contact me off line and we can continue the conversation for your project.

    ME

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  • BC_15
    BC_15 Member Posts: 2
    Mark

    As you may or may not have noticed I'm usually one of the first to call out a heating or energy related scam when they crop up on this board. I have to say the only thing keeping me back in this case is your involvement in the project. Taking all the information you've given us over the last year or so, it's obvious that it's no scam and you and others honestly believe in the product. However, I've yet to see an explanation as to why these work - information on the website is very sparse. I can't even read the numbers on the 2 graphics under the test section.

    For example, if I take an R-3 window and simply glue a heating element to one side of it and maintain the surface temperature at 100F (room temp 70F, outside temp at 0F) I should get about 60btu/hr to the room and 33btu/hr to the outdoors per sq. ft. That's roughly 35% of the heat going outside, not 15% as the website claims. Obviously something is increasing the effective r-value of the window - what is it? Obviously some of this is proprietary but I assume the key aspects are patented so I would hope to see a lot more technical information.

    I'm NOT doubting you or the researchers at Kansas state - I just want to get my mind around this so the part of my brain that is screaming about physical laws being violated will shut up. Thanks!

  • ttekushan_3
    ttekushan_3 Member Posts: 960
    Have you measured

    Visual Transmittance?

    Terry T

    steam; proportioned minitube; trapless; jet pump return; vac vent. New Yorker CGS30C

  • Gordy
    Gordy Member Posts: 9,546
    Coatings ?

    Not speaking for Mark but I don't think your example is that simple.

    I'm sure the type of glass, glass coatings, and event the actual SF of the glass can help to reflect that radiant energy where you want it to go, inside.

    I ahve no doubt this type of window can do what it claims. What concerns me is the cost of electricity to operate it at the temps needed to do something viable.

    If your utilities are cheap in your area no concern needed. But at 11 cents a kilowatt it starts to get pricey to operate a heat source like this....Unless solar PV can be integrated to suplement. Of course it also depends on the intended application. Total heating, maybe the north side of the dwelling only, or even maybe a sole room where majority of time is spent.


    I think its a great tool in the arsenal of radiant heating speacializing in low load situations, not a silver bullet.


    Gordy
  • BC_15
    BC_15 Member Posts: 2


    Yes, my example was obviously very simplified - in the real world lots of other factors come into play. However, the difference they're claiming is so huge, something must be happening. If a simple low-E coating or something was that effective, why wouldn't it apply to non-heated windows as well. I'm not doubting at this point, just looking for more info on what makes these windows perform at an apparent R-7ish.
  • Gordy
    Gordy Member Posts: 9,546
    Added benifit of the glass material component

    I'm guessing... When the research is all done that the conductive material used in the glass making process may be the actual component that is causing this r value benifit.


    It would not be the first time that a material designed for something has other unintentional benifits with in the invention, or completly outside its box.


    There is much we don't know right now to judge, with good reasoning. It just works, the mystery is why. I like mysteries.

    Gordy

    Gordy
  • Gordy
    Gordy Member Posts: 9,546
    Wow

    I have not revisited RGI website for quite some time. Things are really looking up. Distribution will be key.


    Gordy
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,852
    Well BC... To be quite honest...

    I have little to no respect for someone who intentionally hides his ID. Hence, I rarely read your posts, so am not familiar with your truth policing.

    As far as how efficient the windows was during that test, it only applies to that window under those conditions. THere are no less than a million different window sizes, and at least 70 to 100 operating conditions, hence the need for the 10 mill cool ones so we can figure it out.

    Trust me on this CB, I wouldn't be investing my time if I didn't think it warranted it, and again to be quite honest, I could care less if it doesn't save an ounce of energy, and neither would the very rich people I'd be putting it in for. When I was first introduced to this product, I saw it operating in a freezer door, and 1/2" away from a glass surface that was 115 degrees F, there was ice forming. I told the person showing it to me that that couldn't POSSIBLY be. He said it has been that way for a long time, and they couldn't explain it either.

    When I first saw the product, I knew I'd found the answer to all of my problems with high glazed areas, and had NO freaking idea that it had the potential of reducing energy consumption by 42%. That's just frosting on the cake, and to be brutally (wore quite out) honest with you, my gut feeling is that in the real world practice, the window may reduce the energy consumption of the building to which it is applied, by 80%.

    But again, we need that spare 10 mill large ones to prove it out.

    So, in short, there are a LOT of things that are extremely bizarre with this product, and I have my theories on it, but would rather not share them at this point until I have more solid data.

    Stay tuned, and start using your real name, will ya? :-)

    ME

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  • Mark Eatherton
    Mark Eatherton Member Posts: 5,852
    If you mean Infrared, yes, we have studied it in that spectrum..

    Inside and out.

    It shows an extremely even temperature rise across the glass even when accelrating from 70 to 115. No hot or cold spots. It is so uniform that you really don't see any color fluctuation. It just changes.

    If you don't mean infrared, what do you mean?

    Thanks Terry.

    ME

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  • ttekushan_3
    ttekushan_3 Member Posts: 960
    visual transmittance

    as distinct from emissivity and solar heat gain ratings. As culled from somewhere in my window file: "Visible transmittance (VT): The percentage or fraction of the visible spectrum (380 to 720 nm) weighted by the sensitivity of the eye, that is transmitted through the glazing."

    A clear single pane of glass is about .89, architectural quality acrylic .92, clear double glaze .81, double glaze low e .77. Adding low solar heat gain films and a third glazing, the VT quickly drops into the .3 to .4 region.

    -Terry

    Interesting research article on the subject vis a vis modern window construction:

    University of Ulster research

    Terry T

    steam; proportioned minitube; trapless; jet pump return; vac vent. New Yorker CGS30C

  • BC_16
    BC_16 Member Posts: 1


    I didn't realize my lack of a last name made my posts so sinister... Seriously, I'm not trying to hide anything - when it comes to message boards in general (and this one in particular because of its popularity and open nature) I tend to keep personal info to a minimum due to all the spammers and various nutjobs out there. BC is my real name (or at least a nickname), and my email is valid so if anyone's really interested, drop me a line and I'll be happy to introduce myself!

    Back to the topic at hand... the glass does sound promising even if the only benefit is comfort as you say. I'll look forward to seeing more when you get results from your test houses.
  • Mars_3
    Mars_3 Member Posts: 65
    Thanks Mark

    I would be proud to offer this product and have proposed this to some of my contractors all ready. The feed back that I get is very favorable and when the stagnation in the lending markets lessens I feel that the potential for this product to escalate will be limitless. the thing about these windows that make them so atractive is that you can marry them up to a pv solar system and BANG how are you going wrong there in this enviroment.
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,852
    Gordy,

    Your guess is correct. There are special metal coatings on surfaces 2 and 3. Window manufacturers count surfaces from the outside going towards the inside. The electricity is being induced in to the glass at surface number 3.

    The metal coating is actually IN the surface of the glass, not ON the surface of the glass. The glass has an inherent resistance value of 14 ohms per square. Not per square foot, although one square foot would have a resistance of 14 ohms, but per square. So if the glass is 10 foot by 10 foot, then the resistance would be 14 ohms. The only thing that changes the resistance is the aspect ratio of length to width. So, if the glass is 3' X 4', then 3 divided by 4 = .75, so the new resistance of THAT glass would be 14 X .75, for a new value of 10.5 ohms. THis assumes the glass is bussed along the longest length. If not, and it is bussed on the shortest length, then 4 divided by 3 = 1.33, hence the resistance of that circuit would be 14 times 1.33 for a new resistance of 18.66 ohms.

    The glass has numerous modes of operation,including thermal opacity (74 degree F surface temperature). anti condensing mode (dictated by RH) and thermal production mode (surface temperature up to 144 degrees F) with an outdoor reset. the surface can be anywhere from 74 to 144 depending upon outside and inside temperatures. (indoor and outdoor reset). Electric consumption obviously depends upon a lot of variables, and yes, you are correct, this is not a silver bullet. Conventional conservation is a MUST, as it is with ANY heat source.

    The inventors initially got their patent and ETL (Ul equal) approval on 48 volts DC power, because they understood the application to solar PV and Hydrogen fuel cells. We need to get re-certified (ETL) for use with AC power and higher voltages Imagine capturing solar energy on the south, and transferring it to the north side of the building, where sunshine never falls...

    And again, yes, this is the largest weapon we have in our war on human discomfort.. and that has been proven time and time again.

    When these guys first approached me almost 3 years ago, they had "A window, that when you plug it in, it gets hot". We now have a very intelligent piece of glass that can make and keep you comfortable. An actual system approach if you will...

    Oh, and by the way, it could reduce your energy consumption by up to 40 %!

    Stay tuned.

    PS, This is the view looking out of my cabin in the mountains. The frost on the lower glass is on surface 1, and the inside glass is running at 116 degrees F. It is -5 F outside. It's like standing in the sun....except these windows face North :-)

    ME

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  • Mark Eatherton
    Mark Eatherton Member Posts: 5,852
    I see said the blind man...

    as he groped along The Wall.

    I will check and get back to you Terry. I'm sure they know.

    ME

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  • Mark Eatherton
    Mark Eatherton Member Posts: 5,852
    Same heat loss calcs...

    you just don't have to include the heat loss of active windows. Also, if you are using the windows as a heat source, you can cut back on the required physical plant necessary to deliver heat and comfort.

    The windows can be zoned by space use. At present, the control package is pricey, but R&D should bring about a less expensive method of power and control.

    Mike is a good guy, and knows more about glass and windows than I will ever know, but he really doesn't know these electrified windows as well as he will when we get the final product down pat..


    ME

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  • Gordy
    Gordy Member Posts: 9,546
    So whats the competition

    Out there in this arena Mark? If you do a search on the web for radiant glass a few come up IQ glass being one of them.

    Are these the same caliber of windows, or is RGI on to something different besides a decent control strategy?


    I'm seeing applications for this stuff everywhere I look Now.

    Gordy
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,852
    The competition is slim...

    IQ Glass is out of Europe. Their product is a thick, cumbersome sandwiched, over priced glazing, hence their primary market is top end solariums and highly glazed swimming pool areas. They are not moving much product from what I understand.

    Thermique, a division of Engineered Glass Products, is currently focusing on unique products like see through towel warmers. From what I understand, EGP is focusing their efforts on the food service industry.THere is one other small firm in Fort Collins Colorado called Point Five Windows that has an electric window, but are not really promoting its use.

    So, at present, the competition is slim, but that could change in the blink of an eye...

    ME

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  • J_Dubya
    J_Dubya Member Posts: 3
    RGI

    I am very intrigued by these window/panels.  I am typically not an early adopter; however, while I was sitting in front of my bay window reading Siegenthaler trying to wrap my head around whether radiant floor heating would be a good fit for my old house,  it occurred to me that someone should make windows that are radiant heating panels.  This was a few years ago, and I posted a question on the Radnet forum whether anybody made such a product -- no and unknown were the responses.  Then I figured I should try to invent such a product -- which of course I quickly dismissed because this is even close to my area of expertise, and I figured many people much smarter than me surely must have had this same thought.



    I only go into all this, because, I am looking for a reality check.  Perhaps I am infatuated with an idea, because it is one that I shared (perhaps channeled) -- and it is potentially such an elegant solution!  Heck, I want to invest in this technology.  I am wondering whether I should temper my enthusiasm and do what I typically do, which is to wait for a product to mature and economies of scale to come to pass.



    I am located in the Pacific Northwest, a relatively mild climate, and the land of hydroelectric low rates ~6 -7 cents/Kwh.  My old house was built in 1899 and has two large window bays with lovely leaded drafty single pane windows  ~180 s.f. of glass.  I hear that AC will soon be available.  What are the tradeoffs between AC and DC?  How many BTU's will 180 sf of glass generate?  It seems to me that if the panes can hit 140 degrees (and I know nothing), that I could use them as a soul source of heat in for ~ 4500 s.f.  zone (living and dining room).



    Are there any data regarding performance that are available at this time?



    I see this was an old post; just hoping to learn more and discover the current status quo.  I have contacted Busick and he is working up an estimate.



    Thank you,

    Jeff Spencer
  • J_Dubya
    J_Dubya Member Posts: 3
    RGI

    I am very intrigued by these window/panels.  I am typically not an early adopter; however, while I was sitting in front of my bay window reading Siegenthaler trying to wrap my head around whether radiant floor heating would be a good fit for my old house,  it occurred to me that someone should make windows that are radiant heating panels.  This was a few years ago, and I posted a question on the Radnet forum whether anybody made such a product -- no and unknown were the responses.  Then I figured I should try to invent such a product -- which of course I quickly dismissed because this is even close to my area of expertise, and I figured many people much smarter than me surely must have had this same thought.



    I only go into all this, because, I am looking for a reality check.  Perhaps I am infatuated with an idea, because it is one that I shared (perhaps channeled) -- and it is potentially such an elegant solution!  Heck, I want to invest in this technology.  I am wondering whether I should temper my enthusiasm and do what I typically do, which is to wait for a product to mature and economies of scale to come to pass.



    I am located in the Pacific Northwest, a relatively mild climate, and the land of hydroelectric low rates ~6 -7 cents/Kwh.  My old house was built in 1899 and has two large window bays with lovely leaded drafty single pane windows  ~180 s.f. of glass.  I hear that AC will soon be available.  What are the tradeoffs between AC and DC?  How many BTU's will 180 sf of glass generate?  It seems to me that if the panes can hit 140 degrees (and I know nothing), that I could use them as a soul source of heat in for ~ 4500 s.f.  zone (living and dining room).



    Are there any data regarding performance that are available at this time?



    I see this was an old post; just hoping to learn more and discover the current status quo.  I have contacted Busick and he is working up an estimate.



    Thank you,

    Jeff Spencer
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,852
    Jeff,

    We tested the windows in 3 Tuff Sheds that were 10' X 12' with identical exposure and identical glazings. I did not see a significant reduction in energy consumption, in fact when used as a sole source for heat, the radiant window shed used more energy than the forced air equal. But the human comfort factor was off the charts. This was kind of a low budget test, and we really didn't get the points of data for detailed analysis that I would like to have gotten, but it is what it is.



    What we did find was that the most efficient mode of operation was the thermally opaque mode, which I have been touting since these people introduced me to their product. The inventors wanted to move forward with this as a sole source heating system, and we have successfully deployed it in that capacity, but based on KSU's findings of 85% efficiency at 10 degrees F and te glass at 115 degrees F, it really doesn't make sense to use them as a sole heat source unless your power source is 100% free (think large solar PV array).



    As I have said all along, these windows represent the greatest advance in the 36 years I've been dealing with human comfort, in addressing human comfort in close proximity to a highly glazed area. I am finding that the optimum temperature for efficient operation and excellent human comfort is 70 to 75 degrees F. Any thing greater than that, surface temperature wise, and the occupants feel like they are being sun burned, and that violates my personal definition of human comfort.



    As I type this, I am sitting next to an array of these windows, it is -3 outside, the MRT and air temp (operative temperature) inside is around 66 degrees F, the glass is 74.8 degrees F, I am medium clothed, and it is perfectly comfortable. I am 2' away from the glass.



    Unfortunately, a deep recession is not a good time to be soliciting funds fro product development and R&D, and the RGI group has had zero luck in getting an investor to step up to the pump to give us the monetary assistance needed to fine tune our findings, so I have had to resort to other means of support. I continue to do R&D at my own facility, but am very frustrated with RGI's inability to get funding and have commitments that I have to make as well. I continue to work with the core group of inventors/technicians in helping out in any way that I can be of assistance, within my limited ability. I have invest way too much time and money to walk away from this product. Besides, it is still, the largest weapon I have in my bag of tricks in guaranteeing good human comfort.



    Just frustrated by the economy.



    In your situation, even though you have a relatively cheap energy structure (hydro) it still doesn't make sense to use an 85% efficient electric heat energy source, when electric base board is 100% efficient, so it WILL generate excellent human comfort conditions in close proximity to highly glazed areas in the thermally opaque (70 to 75 degrees F) mode. As far as energy consumption, my windows draw about .6 watts per square foot per degree F difference in inside an outside temperature, and as it gets warmer inside and outside, the glass gets warmer and has to be limited in surface temperature, otherwise it gets uncomfortably warm.



    One of the early limiting factors was the core group of inventors going for a maximum of 8 volts DC power in their ETL approval. They were dealing with small pieces of glass, and it got them extremely hot. This isn't rocket science. It (the glass) is dependent upon watt density per square foot to achieve a temperature, and it is dependent upon conditions of exposure as to how hot the glass gets. As we did larger pieces of glass, it was obvious that 48 volts wasn't going to cut it on larger pieces of glass, hence the reason they (RGI) wants to get re-certified thru ETL/UL for higher voltages. It will also help in base power supply efficiency, because when going from AC to DC and vice a versa, there is an inherent reduction in conversion efficiency. I was power factors as low as 50% on some early power sources used by the group. In my own "lab" here in Heeney, I am using 120 volts, but am splitting it amongst 3 windows wired in series, so essentially I am pouring 40 volts per window. In order to do this, all windows MUST be the same size, same resistances etc.



    I am doing personal research on a controller that will have the ability to pulse power to the glass based on need and deviation between dictated set point and actual set point, and personal wishes, wants and needs as it pertain to comfort. It looks promising, but again requires a significant amount of money to run through the process of certification, and there is none to be had.



    So, R&D is an ongoing situation, but the one thing we have proven with each and every installation is that human comfort is significantly influenced whenever we use them, and for this business, it is a good thing.



    As far as how many BTU's the glass will put out, as with hydronics, the only correct answer is, It Depends. If you can give me the actual physical size of the glass, I can calculate the thermal capacity of the window based on known information.



    I too am enamored with the technology (DUHHhh) and have lost many an hour of sleep thinking about the potential applications of this product above and beyond human comfort, like fogless mirrors (ever wonder how many maid hours are spent cleaning bathroom mirrors fouled by a man wiping the condensate off the mirror in the morning so they can shave?) heated windshields for armoured vehicles (conventional window defrost systems don't work well when they are real thick) and more.



    Thanks for the inquiry.



    Frustrated in Heeny, but VERY comfortable :-)



    ME

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  • J_Dubya
    J_Dubya Member Posts: 3
    RGI in Pacific Northwest

    Mark, Thank you for your thoughtful and informative reply.  I am infatuated with the technology for sure.  In that you have a long term relationship with the technology and have endured some of the bumps, and you're still enamored, speaks volumes.  I am no HVAC guy, just a layman with an interest, so some of my questions will likely be silly.  That being said, I have a few additional questions.



    My 2 window bays consist of three DH windows each , with the top panes at about 66" high to ~ 102" (9 foot ceilings).  I was wondering whether it might be smart to run the upper panes at a lower temp (perhaps thermal opacity) and run the lower panes at a higher temp.  The idea being to provide comfort to the person sitting in the chair on the window seat, and also the occupants in the room.  In order to shave costs, an extension of this idea would be to install regular dbl pane glass in the uppers and the RGI panes at human level.  Or might this cause some unpleasant circulation?



    Would my small residential application be better served with an AC system as opposed to a DC system?



    In the Pacific Northwest with less extreme temperature variation than the Rocky mountans, would RGI provide more comfort benefit per KWh or less comfort benefit per KWh?



    On the funding topic, again just a layman, but I ride bikes with a couple of guys who have related experience.  One specializes in preparing biotech companies for IPO's, the other guy is a CFO for a local company but has done some other stuff; both have international experience.  Another of my good buddies is married to the daughter of a family who has a prominent large window manufacturing company here in Pierce County.  Just a shot in the dark, I suppose there are a couple of questions there, one, regarding acquisition of venture capital and two, penetration into the Northwest markets.  If they can't help perhaps they know someone that can. Good ideas also need good business models (and good economic environments).  What kind of funds are needed to get the validation that is necessary?



    Thank you,

    Jeff Spencer 
This discussion has been closed.