V3Solar

Shadowcatcher
Shadowcatcher Solar Expert Posts: 228 ✭✭✭
Some one posted a link to http://v3solar.com/ on the Teardrop & Tiny Travel Trailer Forum and it sounds too good to be true. The claim is 20X efficiency of a flat panel solar.
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Comments

  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: V3Solar

    another scheme. it is a concentrator type arrangement that at least solved for the cell heating, but only a small amount of cell area is illuminated at any one time and concentrators are somewhat direction dependent in spite of their efforts. the bottom line is it won't produce more output than a standard pv occupying the same area so why pay more for it?
  • Robert S
    Robert S Registered Users Posts: 3
    Re: V3Solar

    We do not increase the "efficiency" of PV by 20X. That would be impossible. We produce 20X more electricity from the same amount of PV by concentrating the sunlight 20X. Please see the full explanation here: http://v3solar.com/technology/readfirst/

    I hope that clears things up for you.

    Best,

    Robert
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: V3Solar

    No, it doesn't.

    You collect sunlight from a large area and concentrate it on a small area. The PV in the small area is subjected to 20X as much light, ergo puts out more power for the space the cell takes up. But you still need to collect from the larger area to get that concentrated power. Ergo there is no advantage over simply having more PV covering the same area as the collector, just as Niel said. There is, however, a disadvantage as concentrating the power onto a small area also concentrates the heat and the PV's are not designed to be subjected to such temperatures. This is physics, and I'm sure inetdog would like to explain it in fine detail.

    I'm not saying it doesn't work per se, just that I see no practical advantage as you end up needing at least the same amount of space for the power ultimately derived.

    Concentrators do work when the goal is to achieve higher point temperature in a thermal system.
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: V3Solar

    Sorry, but call me skeptical. (doesn't mean I can be convinced, but I need to see more,, and a track record)
    Inutitively is seems a stretch to think that you are increasing net efficiency by what you propose. Isn't there energy required to drive the cones? Doesn't the fact that the PV is only at optimal angle for a few degrees of the rotation imply that the other degrees result in lower EF?

    In my world, the beauty of PV is,,, no moving parts, no sound, no maintenance. in this case you are introducing all three.

    Tony
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: V3Solar
    Robert S wrote: »
    We do not increase the "efficiency" of PV by 20X. That would be impossible.

    From your web site: "The V3solar patent pending design also delivers a higher level of efficiency from PV. Tests to date have shown improvements under laboratory conditions of around 30%, which effectively lifts the efficiency of the PV."


    Maybe you should fix the wording on that.
  • Robert S
    Robert S Registered Users Posts: 3
    Re: V3Solar
    No, it doesn't.

    You collect sunlight from a large area and concentrate it on a small area. The PV in the small area is subjected to 20X as much light, ergo puts out more power for the space the cell takes up. But you still need to collect from the larger area to get that concentrated power. Ergo there is no advantage over simply having more PV covering the same area as the collector, just as Niel said. There is, however, a disadvantage as concentrating the power onto a small area also concentrates the heat and the PV's are not designed to be subjected to such temperatures. This is physics, and I'm sure inetdog would like to explain it in fine detail.

    I'm not saying it doesn't work per se, just that I see no practical advantage as you end up needing at least the same amount of space for the power ultimately derived.

    Concentrators do work when the goal is to achieve higher point temperature in a thermal system.

    The advantage is that the concentrating material is much less expensive than the PV material. So if we can concentrate 20X sunlight on 1/20th of the PV and NOT increase the heat, that is the breakthrough. Everyone knows that concentration can increase production, but the associated heat has been a problem. That is what we solved through the spin. Light is transferred to electricity in nanoseconds and heat is transferred in milliseconds (1000X longer). The PV captures the light and spins away before the heat can be transferred.
  • Robert S
    Robert S Registered Users Posts: 3
    Re: V3Solar

    Yes...increasing the efficiency from 20% to 30% is possible. Increasing by 20X is not possible.
  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: V3Solar
    Robert S wrote: »
    We do not increase the "efficiency" of PV by 20X. That would be impossible. We produce 20X more electricity from the same amount of PV by concentrating the sunlight 20X. Please see the full explanation here: http://v3solar.com/technology/readfirst/

    I hope that clears things up for you.

    Best,

    Robert

    I saw the "full explanation" and I was not at all impressed. Just a few points, among many:

    1. Concentrate the light on a very small area (20x) but spread the heat over a much larger area by spinning the cell? So you get the reduced cost of using only one 20th the amount of "expensive" silicon (or maybe more expensive exotic material combinations?) and then to get past the thermal problem you multiply that area by 20 again and only have the light shine on 1/20 of the array at one time? I guess I am missing the point somehow.
    2. Light travels extremely fast and is converted to electricity in microseconds (actually less than that!) while heat travels more slowly. Everyone knows that, right? But in this case the heat arrives simultaneously with the light. It is the light which is neither reflected nor transmitted nor converted to electrical energy that creates the heat. No time difference/speed difference at all. Agreed, it will take awhile for the constant incoming heat to actually increase the temperature. In which case look back at point #1.
    3. Resonance? You have got to be kidding! :-) Maybe the black monoliths which played such a significant role in "2001, A Space Odyssey" were really solar collectors?
    SMA SB 3000, old BP panels.
  • ggunn
    ggunn Solar Expert Posts: 1,973 ✭✭✭
    Re: V3Solar

    A couple of things come to mind...

    Most of the time, most of the PV is in the dark. It's great if the PV which is producing electricity is doing so at a higher efficiency, but at any single point in time, most of the PV is "resting" - dissipating heat without producing power. On a given day, how much electrical energy does it produce per square meter of PV material?

    What spins the array? How much power is required to keep it moving? Obviously, that expenditure subtracts from the net production of the system.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: V3Solar
    Robert S wrote: »
    The advantage is that the concentrating material is much less expensive than the PV material. So if we can concentrate 20X sunlight on 1/20th of the PV and NOT increase the heat, that is the breakthrough. Everyone knows that concentration can increase production, but the associated heat has been a problem. That is what we solved through the spin. Light is transferred to electricity in nanoseconds and heat is transferred in milliseconds (1000X longer). The PV captures the light and spins away before the heat can be transferred.

    Nice idea.
    Now, can you do it for less than 20 cents per Watt? The price of PV's is so low right now that the increase had from this would have to be available for a really low price to make it worthwhile. Plus there is the added complexity to consider, as Icarus mentioned.

    Technically it may work. But is it practical? We see many "breakthroughs" is solar technology that die an instant death because the gains they offer are too small for the additional money they cost.

    I also can't help wondering what effect forcing the cells to produce 20% more power will have on the cells themselves as they inter-act. Usually any method that increases the current or Voltage has a detrimental action on the cell itself, including reverse current problems and increased operating temperature from the increased power production (as opposed to from heat absorption).

    For some reason I think what is really meant by "20% increase" is a 20% reduction in the power degradation that would normally be experienced due to heat absorption by the cell. Maybe you could just use whatever powers the spinning cones to blow air across the panels.
  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: V3Solar
    Maybe you could just use whatever powers the spinning cones to blow air across the panels.

    And that brings up another point: The magical magnetic bearings.
    It will not take much power to spin the cone and keep it spinning. Except for the fact that the cooling effect of the air will go hand in hand with air resistance, so if it does any good, it will take more power then just the bearing friction.

    Maybe if you design a fan with good enough bearings, it can keep turning and blowing air with no power input? (Why does that remind me of small wind turbines???)

    Too bad.....
    SMA SB 3000, old BP panels.
  • jg167
    jg167 Registered Users Posts: 4
    Re: V3Solar
    Some one posted a link to http://v3solar.com/ on the Teardrop & Tiny Travel Trailer Forum and it sounds too good to be true. The claim is 20X efficiency of a flat panel solar.

    Since V3 claims to have a full scale working prototype, all they have to do is take it to a top university/lab (they are in LA so plenty of them nearby) and say "here, test this". So why haven't they done so? Makes me skeptical. I mean they are not claiming a 10% improvement but a 2,000% improvement so it should be very easy to verify.

    I will admit to being largely ignorant of PV physics, but if the lens is a 20x light concentrator, but the PV spends only a fraction of the spin under it I don't see how a 20x efficiency is possible.

    The whole explanation of the water flowing over the full buckets for why the PVs are more efficient under flickering as opposed to continuous light, also seemed to have a veery high "hand waving" factor.

    Still, they (or the artist's conception of them) look REALLY cool! It would be fantastic if true, but I remain skeptical.
  • peakbagger
    peakbagger Solar Expert Posts: 341 ✭✭✭
    Re: V3Solar

    Sort of reminds me of some of the solyndra hype. Extra power due to self focusing and no need to aim.
  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: V3Solar
    peakbagger wrote: »
    Sort of reminds me of some of the solyndra hype. Extra power due to self focusing and no need to aim.

    "Ready, Fire, Aim!" ? :-)
    SMA SB 3000, old BP panels.
  • jg167
    jg167 Registered Users Posts: 4
    Re: V3Solar

    Oh also, since the PVs are moving I presume they take power out via induction from the electromagnets in the fixed base??? That has to impart an efficiency hit as well.
  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: V3Solar
    jg167 wrote: »
    Oh also, since the PVs are moving I presume they take power out via induction from the electromagnets in the fixed base??? That has to impart an efficiency hit as well.

    ??? Not unless the moving wires are themselves in the strong field area of the suspension magnets, which are probably at the axis, and that field is radial, which it probably is not.
    SMA SB 3000, old BP panels.
  • jg167
    jg167 Registered Users Posts: 4
    Re: V3Solar
    inetdog wrote: »
    ??? Not unless the moving wires are themselves in the strong field area of the suspension magnets, which are probably at the axis, and that field is radial, which it probably is not.
    Yea but they say "no moving part rubs against each other" so how else could they do it?
  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: V3Solar
    jg167 wrote: »
    Yea but they say "no moving part rubs against each other" so how else could they do it?

    I think they have to make an exception for the current carrying wires to use brushes and slip rings, or similar. Although there is a clever mechanical trick that can let you get an electrical circuit off the rotating member using an ininterrupted flexible conductor which does not just get wound up tighter and tighter. :-)
    SMA SB 3000, old BP panels.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: V3Solar

    It is trick wording: many electric motors have "no moving parts that rub against each other". Your typical AC induction motor has one moving part: the armature assembly. The only parts it contacts are stationary: the bearings it rides on.

    Although I suppose you could get picky and say the centrifugal switch that disengages the start windings is a moving part that the armature moves against ... :roll:
  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: V3Solar
    It is trick wording: many electric motors have "no moving parts that rub against each other". Your typical AC induction motor has one moving part: the armature assembly. The only parts it contacts are stationary: the bearings it rides on.

    Although I suppose you could get picky and say the centrifugal switch that disengages the start windings is a moving part that the armature moves against ... :roll:

    And in the theoretically perfect ball or roller bearing, there is no rubbing among moving and/or stationary parts, just rolling with no relative motion at the contact points.
    SMA SB 3000, old BP panels.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: V3Solar
    inetdog wrote: »
    And in the theoretically perfect ball or roller bearing, there is no rubbing among moving and/or stationary parts, just rolling with no relative motion at the contact points.

    Hey, how far do we want to divide this down? The molecules in the lubricant between the metal components of the bearings? :D
    Gets silly, doesn't it?
  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: V3Solar
    Hey, how far do we want to divide this down? The molecules in the lubricant between the metal components of the bearings? :D
    Gets silly, doesn't it?

    Well, even near absolute zero, there is relative motion of the atoms within a solid block of steel. :-)
    SMA SB 3000, old BP panels.
  • ggunn
    ggunn Solar Expert Posts: 1,973 ✭✭✭
    Re: V3Solar
    peakbagger wrote: »
    Sort of reminds me of some of the solyndra hype. Extra power due to self focusing and no need to aim.
    Except that Solyndra stuff actually works. They went under because they couldn't compete price-wise, not because their modules didn't work. Granted, they didn't seem to work quite as well as they claimed, but they did work.
  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    Re: V3Solar

    This all sounds like SPIN, to me. Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • ggunn
    ggunn Solar Expert Posts: 1,973 ✭✭✭
    Re: V3Solar
    Vic wrote: »
    This all sounds like SPIN, to me. Vic
    Are you talking to me? Solyndra modules do work. My company installed a 300kW rooftop PV system built with Solyndra modules over a year ago and it is working fine. The tubes are not as hailstorm resistant as we would have liked (in retrospect perhaps Dallas was not the best location for it), and the module price would not be competitive in today's market, but the modules work.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: V3Solar

    Hail resistance==Yea, I had that concern too. Flat panels seem to be better at that.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • ggunn
    ggunn Solar Expert Posts: 1,973 ✭✭✭
    Re: V3Solar
    BB. wrote: »
    Hail resistance==Yea, I had that concern too. Flat panels seem to be better at that.

    -Bill
    I don't know if they are worse than flat panels at resisting hail damage, but a major hailstorm in Dallas broke a lot of tubes in our Solyndra installation. Insurance covers the damage, but finding replacements... It's problematic at the very least.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: V3Solar

    Here is a video about tempered glass and golf balls:
    BB. wrote: »
    Here is a neat youtube video on regular vs tempered glass (alternate video source)...

    Shows a big picture window, one in annealed glass, the other in tempered glass, showing that a thrown baseball will go right though annealed glass. Whereas tempered glass it just bounces off...

    They also did the same thing with a golf ball--Difference is that the golf ball that hit near the frame went right through the tempered glass while balls that hit the center did not.

    One other difference was the glass used for the test looked to be ~1/4"-5/16" thick or so. Whereas solar panel glass is 1/2 the thickness.

    The video claims that tempered glass is 4-6x stronger than annealed glass.

    One error in the video (or maybe over simplification) is they show the the stresses from tempered glass as running perpendicular to the surfaces of the glass...

    In real life, the surface of the glass is in compression while the center of the glass is in tension. Any stress cracks that try to develop in the surface of the glass are held closed by the tension in the core--until the surface stresses exceed the compression from the inner core.

    Basically glass and concrete (another example) are very strong in compression but weak in tension. With Glass, any defects in the surface when under tension cause the cracking to start and progress throughout the depth of the material.

    Glass is heated to near melting (pre-cut to the correct size as tempered glass cannot be cut to size), then the outer surface is quickly cooled (quenched) by air jets--this solidifies the surface. Now, the inner glass cools more slowly and starts contracting. This allows the inner glass to put compression in the outer surface.

    And here is another video that compares flat plate against solar thermal tube collectors and ease of damage:
    Slappy wrote: »
    then here is a video of a solar panel with baseballs being lobbed at it. http://www.youtube.com/watch?v=SV3euyl8mlw
    jump to 3:47 in the time frame of the video?

    Could not find out if the Solyndra tubes were tempered glass or not (a video of the tubes being destroyed seemed to look like tempered glass breaking).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • mtdoc
    mtdoc Solar Expert Posts: 600 ✭✭
    Re: V3Solar

    Thanks for the links to the videos.

    The issue of how tempered glass breaks is on my mind today. Last night our almost new toaster oven door inexplicably shattered while heating up a tortilla. There must have been a small defect that acted as a nidus for a crack to develop when the glass expanded with heating. Now I've got to see if Black and Decker will honor their warranty for this - not looking forward to calling them....(update - just got off the phone with B and D customer service. Suprisingly they agreed to send me a new toaster oven. But the rep said "don't heat up tortillas in the toaster oven" ???? She said they have oil in them that can cause the glass to shatter! ??? :confused: - well i guess one lesson - don't try to heat a tortilla on your tempered glass solar panel..:roll:.)

    BTW - ggunn - I think Vic was just making a funny with the "it sounds like SPIN" comment (watch the V3 Solar video if you haven't yet and you'll see).
  • inetdog
    inetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: V3Solar

    I found the way they tested the solar PV panel interesting: they measured the open-circuit voltage. Since there is not much short of total destruction that can alter the Voc of a cell, I suspect that the first break caused a couple of cells to short out while the Vesuvius test may have also caused some broken traces which were bridged by the action of the bypass diodes.
    SMA SB 3000, old BP panels.