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At last, window resolution... (ME)

jp_2 Member Posts: 1,935

I'm not really seeing the benefit of running windows with DC?

i understand you want the ability to use solar panels but thats a very costly solution that will only work part time.

I think DC power supplies are going to be less efficient than using AC? maybe an autotransformer is a better solution?

you can also use an isolating transformer and float the ground, this will give you about 50vac to ground both sides of transformer.


  • Mark Eatherton
    Mark Eatherton Member Posts: 5,837
    It's not 265% efficient...

    Wallies, some of you and I had conversations in the past with me explaining the dilemma that I was having with the NGML's testing of the window.

    In a nutshell for those who I didn't have the conversation with, in the course of having the window tested, KSU said they were seeing 160 btu's per square foot per hour coming out of the glass. The only problem was, we thought we were only pouring 60 btu's per square foot per hour IN to the glass. That's a 265% deviation. We asked them to review their data, to which they replied that they had reviewed the data, and were comfortable with the information delivered. That was before we explained to them that we had set up the DC drives to deliver around 60 btu/sq.ft./hour, or so we thought.

    We had their students verify DC voltage being fed into the glass, along with amperage, and subsequent wattage/btu. They verified what we already knew, or thought we knew. The interesting thing about this glass is that it continues to baffle us, even when we think we have a decent handle on its behavior.

    Again last Friday before Wetstock, KSU came back and said they had re-analyzed the data on the output and were comfortable with their findings. I again pointed out to them that they were stating that the window was putting out 2.65 (265% efficient) times the amount of energy we were putting in to the window on the DC side of the equation... They asked me to not publish that data (which had already been published for 6 months) and said they would get back to me in the near future with an explanation.

    Fast forward a week. Tony, one of the sparky inventors, gave me a solar cell to test on the glass. I hooked it up and it powered up to 17.12 volts, at 1.82 amps. Ohms law worked perfectly in this scenario. The window has a resistnce of 9 ohms.

    Solar DC power is about a clean a DC signal as you can get. Although the window did warm up to around 115 to 120 degrees F, it just didn't seem to have the acceleration that we see out of the DC motor drives we've been using. So, I decided to data log the window under full sun to see what affect 17 volts of pure DC power had on the window, then I hooked the window back up to the DC drive and set it for the same power setting of 17.12 volts and fired it up. The window SHOT up to 250 degrees F in a very short period of time. HMMMmmmm. Ain't no way that the DC power from the DC drive is any different than the DC power obtained from the solar panel. Amperage matched the amps seen during the PV test.

    So I decided to test the window on 17.12 volts AC power, and it mimicked what I had seen from the solar cell. Slow acceleration and a max temp around 120 degrees F. And the amperage matched that of the DC drive as well as the DC solar cell. But something was definitely not right. In an effort to figure it out, I set my DMM to AC power and checked across the leads going to the window, and guess what I found...50 volts of AC power that typically slips through the DC motor drive. The window sees the 50 volts, and converts it to watts the same way if does DC power. The only problem was, we were looking at the DC output and never even expected to see ANY AC power on the DC outlet.

    Fiddle faddled by the fickle finger of fate, and a frickin KB DC motor drive.

    I guess that when you are dealing with motors, especially those designed for DC operation, letting the AC bleed though the control has no effect on the DC motor, so the drive manufacturer doesn't bother to filter it out. But the window SEE's the AC voltage and converts it to heat. This explains the poor efficiency of the drives we were using. After re-evaluation, the DC drives are actually about 95% efficient when taking into consideration net delivered power (AC and DC) to the window. This is what happens when you are trying to lower the cost of the equipment, and still deliver the goods. Such is the nature of research and development. The DC motor drive was not intended to be use as a heat source, only a variable speed motor controller.

    Just as a means of verifying it, the guys gave me a PULS brand of DC inverter, typically used to power computerized equipment that has no detectable AC on the DC output. I hooked it up to the same subject window, and the window has stabilized at around 204 degrees F at 44 volts DC.

    Mystery solved. I can sleep at night now knowing for certain that we have not discovered a new source of energy :-) All of the guys I work with are practical people, and other than the lawyer who represents the group, no one really wanted to believe that the windows were capable of producing more energy than they consumed, but it sure looked that way initially.

    Now, I can quit looking over my should expecting to see G.E. or some other power producing firm trying to run me over to keep my secret quiet:-)

    Upward and onward. Now, you might just understand the comment that I made some time ago about looking like a lunatic :-)

    ME a.k.a. Watthead West
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • J Prisby_2
    J Prisby_2 Member Posts: 10
    It happens!


    I give you a lot of credit for sticking to what you believed in. You kept believing when others couldn't see what you were seeing. I am glad to see that there was some reason behind your original findings and to keep us all posted on what was uncovered.

    Always a pleasure seeing what you and many others have to say!

    Jim Prisby

  • Mark,

    You're an inspiration to anyone who's ever had a tough tech dilemna.

  • Derheatmeister
    Derheatmeister Member Posts: 1,140

    Is it close to 100% Efficient?

    Like with a Water heater it should transfer close to 100% of it's energy into the Glass ? besides some outwards loss and wiring loss ,Which reminds me , I do not remember if i asked you about what will happen if one decided to submerge it in water ?( well not the electric part!)will the radiant part still work? do not think so!
    give me a call when you got time.. Richard :-)
  • Actually...

    as a part of their ETL approval, they were required to fill the annulus between the panes with SALT water, and power it up. Duffy said it made all kinds of really cool looking colors, and lots of gas bubbles and kept on heating. He has that pane in his own house and uses it whenever he's cold.

    I'll be in touch.

  • A.J.
    A.J. Member Posts: 257
    Great Job

    Sleep well tonight Mark you earned it.
  • Chap
    Chap Member Posts: 42

    inspiring! Keep up the great work pal.
  • Weezbo
    Weezbo Member Posts: 6,232

    Thats the way to go..

    i still happen to like any "experimental fact finding missions" that may help people accentuate the positive development of Good ole Mr. Sun..:)

    Scientists ask the question What are we observing Here....when you Can explain it with math and our current understanding of the Laws of physics... it is satisfying even when it does not particularly meet up with ones expectations...

    Dr.'s Practice..:) that doesn't deter them from making advances:)

    sometimes one simple operation or one single application is changed and a light comes on and Bang! There it Is!
    well, i think you supplied plenty of scientific rigor to ascertaining the applicabilities *~/:)

    Way to Go...secretly i had hoped that there would be some special knowledge drawn would help reduce energy heat loss by collecting the light and controlling the surface temp of the glass..i probably wouldn't give up just yet..and look for some absorptive ceramic that could enhance only one part of the window :)

    You did right , well i'm off n running ..thanks for sharing this adventure ...

  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 15,447
    I love

    your tenacity.
    Retired and loving it.
  • jp_2
    jp_2 Member Posts: 1,935
    so then?

    where does this leave the outward heated window losses?

    sorry if i missed this point eariler.
  • Testing, testing, 1,2,3.. Can anyone hear me out there???

    jp, The window is still in testing. KSU is performing ABOVE testing on the window right now to deterrmine maximum operating efficiency and ideal operating temperatures to maintain perfect human comfort conditions. I will let everyone here know the results as soon as they become available.

    We had our weekly meeting last night, and much to my chagrin, the master electricians proved to me that there is no AC power making it to the window. Only square wave sine DC power, or what they lovingly refer to as "dirty DC" power.

    They explained it to me this way, and their explanation makes sense, kinda. They also demostrated it to me using an oscilliscope, which can not lie.

    DC power off of the solar cell is extremely pure. On an oscilliscope, it appears as a dead flat line from left to right across the screen at a fixed voltage. When we viewed the window under power through the DC motor drive power source, it was in fact a square sine wave. To prove their point, we hooked the O scope up to the 24 VAC transformer and saw the usual 60 cycle oscillation one would expect to see in an AC circuit. We then hooked it up to a Pure Sine DC inverter, and the sine wave again was flat as a board.

    We (they) have no plausible explanation as to why it was that 14.1 volts of dirty DC power caused the window to sky rocket up to 250 degrees F, other than conjecture that the dirty DC power causes more excitation of the electrons at the face of the glass, hence more vibrations, more friction and more (2.65 times more out than in) heat. Anyone got a spare electron microscope laying around that they could let us borrow for an evening?

    This is a great bunch of guys that I am working with. In fact, both of the sparkies are regular instructors on the union shop level. They know their stuff. Me? I'm just a stinkin' plumber who is trying to wrap his head around this magnificent comfort tool. I keep telling myself that it is impossible that the unit is producing more power than it is consuming, but when I apply DC Ohms law to the window, using 14 V AC, 14 Volts solar (pure) DC and 14 volts DC dirty power from this variable speed motor drive, Ohms law works out perfectly, except that the reaction at the glass is significantly different, with the DC motor drive sending the glass (1.9 square feet, 4.75 lbs) to 250 degree F with a surrounding ambient of 70 degrees F., and the AC and pure DC only got it to around 120 degrees F.

    So, now that the information is "out of the closet", I will probably be viewed by some people as a kook. Some wild eyed wild haired professor in a lab with a tesla coil sizzling in the back ground :-)

    The worst part of all of this, is that I have to go back to the good folks at KSU, and tell them that I was wrong, and that it does appear that the window is producing 2.65 times as much energy as it is consuming. It's not so much th retraction that hurts, as it is drawing them back into the unknown abyss. These people aren't comfortable working outside the box, where things aren't as they appear to be.

    As Professor Chapman said, "That is why they call it research. You search, then you re-search and re-search some more..."

    Back to the sleepless nights. Any and all reasonable explanations will be accepted and passed along to the sparkies.

    Thanks for playing along Wallies.


    PS, I have NO intention of selling this device based solely on its caloric capacity, but if in fact it is 265 % efficient, I think SOMEONE should know....Don't you agree?

  • Ted Robinson
    Ted Robinson Member Posts: 126
    Some random comments on the thread

    It is easy to accept the measured results using 'pure' steady state (flat line) dc. Your voltage and current meters are calibrated to be quite accurate.

    The dirty dc from the motor drive could be a measurement problem. If the output is square wave it cannot be sinusoidal.

    Most common ac meters are calibrated to read accurately clean sinusoidal power as RMS (the usual AC measurements) even though they are 'average responding'. Fluke and others do sell true - RMS responding DMM's that will accurately measure square wave or other non-sinusoidal power.

    All bets are off on the measurement accuracy of the power from the dirty dc drive as the DMM's used are probably not calibrated to accurately read the dirty dc waveform.
  • jp_2
    jp_2 Member Posts: 1,935
    electricans and electronic technicians

    are too different animals with different background in two different fields. I'm not knocking the 'sparkies', but I don't think this is their strong area.

    you can not apply ohms law to circuits with a varying voltage waveforms. remember the reactance we spoke of on circulators months ago? square waves, though apparently low frequency have very high frequency components.

    just as your volt meter didn't read the square wave properly, your current meter is also, most likely, not reading the actual current being drawn. unless you are measuring it at the wall plug before any modification to it.

    it could be possible that the square wave is effecting the window film similarly like a microwave oven effects water molecules.

    what is the composition of the film? sure its a pure resistance?

    I would have the electronics dept set it up on a frequency generator and see if it has a resonant point, no need for electron microscope. leave this to the electronics people, not the electricians
  • We have both on our team...

    One is a NICET certified instructor on fire alarms and communications systems, and the other sparkie deals with the high voltage side of the systems. So we have both on the team, electronics master electrician and regular master electrician. And yes, they too mentioned the possibility of a frequency generator.

    The film is actually a pyrolitic process applied while the glass is still molten. It is a tin oxide.

    Any one want to watch some glass blow up?

  • Dale
    Dale Member Posts: 1,317
    good meter to use

    ME, if you can try a Fluke 123 ( or the newer version) industrial scope meter. The meter shows just what the input or output waveform looks like, or if a straight line true DC. I use it to see what really comes out of power supplies, the cheap ones just chop off the bottom of the sine wave. I use the thing to show the young guys how a 12V battery powers a gas valve just like 24V tfmr, and that while 2 12V batteries in series sounds good it isn't good for the valve coil.
  • Jim Pompetti
    Jim Pompetti Member Posts: 552

    Mark I have something that my interest you . If you send me your e-mail address ,I'll forward it to you .


    [email protected]
  • jp_2
    jp_2 Member Posts: 1,935

    mark, i only mentioned that based on what I have been reading from you, some confusions in my option, should have quickly resolved themselves. but understand, my background is in electronics, and the oscilloscope was a basic tool to use.

    not sure what NICET certified instructor means?
    does this mean he has a degree in electronics theroy?

    I also do not know how much electronic theory a master electrician would have, again the fields are completely different, as you wouldn't ask an electrician to fix your TV.

  • jp_2
    jp_2 Member Posts: 1,935
    keep in mind ME

    I am patiently waiting for solid data so I can decide whether or not to recommend these windows and the true cost to run these windows in my climate.

    not always comfort at any cost.
  • Work in progress...

    Unfortunately, due to techincal diffugulties, KSU is going to have to delay the release of the performance data from the ABOVE program.

    NICET = National Institute for Certification in Engineering Technologies.

    He tore his first TV apart when he was 9 years old...and fixed it and put it back together again. Pretty brilliant in my estimation.

  • Bill Clinton_5
    Bill Clinton_5 Member Posts: 38
    too much power

    Hi, Mark: I am far from an expert in this stuff, but a thought pops into my head now and then. Could it be that the DC motor drive in some way anticipates what it would experience if a motor were attachen, not a resisitive load. When a motor is starting, it draws an enormous amperage: lights dim. Once it gets going, induced magnetic fields from the moving rotor produce what is called a "back emf (electro-motive force) that works the opposite direction. The difference between the "back emf" and the initial resistive current draw equals the power draw of the motor.

    Guessing that the motor drive anticipates the "back emf" but doesn't find it and therefore sends out the kind of current required by a locked-rotor motor or any resistive load.

    Makes sense to me, but I don't know anything about dc motor drives, so it may be nonsense to someone who does.

    Bill Clinton
  • Beats me Bill...

    But I do appreciate the thoughts...

    Right at this moment, in my quest to understand this beast, I did some testing with a 1.9 square foot piece of glass using the DC motor drive at various voltages on the DC side in 1 volt increments, and checked the amperage and voltage on the AC side as well as the DC sides of the motor drive controller. Apparent efficiency of this drive when being used in a resistive load application sucks. I suspect the motor drive controller thinks it has a locked up rotor on a DC motor and is doing something strange with the power.

    I have in my possesion, a pure DC power supply, and I am going to attempt to match the AC wattage of the motor drive to a DC wattage of the power supply and see if there is any co-relation.

    I will report back later after data retreival.

    Thanks for the input.

  • Larry Weingarten
    Larry Weingarten Member Posts: 2,295
    Silly thoughts...

    ...are my forte. So, here's one. How about putting the glass in a known volume of water just to verify the heat output? Energy input has been questioned, but the output hasn't been double-checked that I see. Silly? ;~)

    Yours, Larry
  • DC vs. AC

    There are more than a few AC windows out on the open market, and they ALL have problems with arcing (not a good thing) delamination and random hot spots.

    The reason for DC is two fold. One is stability, and the other is for use with ultimately green products (PV and Hydrogen FC).

    As you can see, I have done some low voltage testing with AC, and am personally happy with the results, however, going back to ETL for reapproval using AC is an expen$ive propo$ition.

    Larry, your idea is really not all that far fetched. In fact, we have a DC thermal generator that we have developed, and will be assembling and testing as soon as I get back from my NJ journey. However, the energy that comes off the glass in this form will be strictly conductive. When it is coming off the glass into a room, it is radiant and convective.

    In any case, it will tell us whether we have stumbled across something more than just a novel idea :-)

  • Larry Weingarten
    Larry Weingarten Member Posts: 2,295

    Mark: would radiant be captured by adding some black ink to the water? Would BTUs be better collected if the container holding the water were black and well insulated? A test to capture all heat output as measured by rise in water temperature could help you to completely surround the apparent problem. "More energy output than input" or "free energy", is either misunderstood energy or energy from an unexpected source ;~)

    Yours, Larry
  • jp_2
    jp_2 Member Posts: 1,935
    bomb calorimeter

    thats what you are talking about larry. do a google and read all about it.

    ink wouldn't help cause everything is in water, you are only dealing with conduction, yes some convection too.

    i'm quite certain it will be found to be less than 100% efficient.
  • Larry Weingarten
    Larry Weingarten Member Posts: 2,295
    Wikipedia is good.

    I'm hoping Mark doesn't put so much voltage to the glass that it explodes :~O His concern was radiant energy not being picked up by clear water. Years ago it was suggested that solar panels could be made out of clear plastic or glass and that water running through could use India ink to pick up the solar energy. One could have solar collectors/windows that would pick up heat and shade the house during the day and drain down in the evening to allow a view. Collectors could even be built into interior walls. Anyway, a little ink would probably not throw off energy measurements much and help make sure any radiant energy got collected. An insulated black "calorimeter" would prolly do the same thing without the ink. I imagine it could be calibrated using an electric water heater element and recording watts used per degree rise. Maybe in the next life, I'll get to be a scientist, or better yet, a cat!

    Yours, Larry
  • jp_2
    jp_2 Member Posts: 1,935
    no radiaant in a calorimeter

    if you stick the window underwater, the radiant element drowns. you are left with conduction only. not the same principle as the solar panels.

  • Thanks guys...

    THere are "EYES ON" for this thread. I will pass the information along.

    And yes, I hope we find it to be less than 100% efficient. I don't want to re-write the history/energy theory books. That said, using conventional wisdom and equipment (DMM's and a Scope) it would appear to be true. I hope that we find the answer soon.


  • Cue...

    "I can see clearly now..."

  • Richard Miller_3
    Richard Miller_3 Member Posts: 61

    For what it's worth (and that may be very little) this is what a friend wrote after reading the thread.

    "I may be off on the wrong path here, but I think I'd like to see energy input measured in smaller than 1 hour intervals. It would also be interesting to see an infrared video of the glass.

    Is it possible that energy is being radiated from the coating to the glass and stored in the glass? When the coating reaches a certain temperature the molecular activity of the glass and the coating syncronize in a way to release the heat."
This discussion has been closed.