Solar panels with no exposed metal.

http://www.sunelec.com/Specs/Abound%20AB-1.jpg

Has anyone had any experience with those? They are around 10% efficient assuming 1000watt/m^2, and $0.49/watt. The datasheet shows no exposed metal, so that would mean no grounding necessary, which could be a nice cost savings. Is it legal just to lay them on a roof perhaps with some ballast? It seems a bit overkill to drill into your roof, install expensive hardware, and clamp them to a metal frame.

Comments

  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Solar panels with no exposed metal.

    "Thin film" panels.
    Not well thought of.
    You can't get a legal GT system without the panels being firmly affixed to the structure or other support.
    Don't waste your money is my advice.
  • john pjohn p Solar Expert Posts: 814 ✭✭✭
    Re: Solar panels with no exposed metal.

    You never have to worry about bolting down thin film panels they never last long enough to make that worthwhile.. Just use blutac it will last long enough. But they will help to keep your roof cool as you will need to cover just about all the roof to get any useful output.
    They are ok for camping or bushwalkers that use them a max of 3 times a year for 3 days at a time. For everone else use the money to buy beer you will be happier . Or buy normal poly panels with aluminium frames.
  • waynefromnscanadawaynefromnscanada Solar Expert Posts: 3,009 ✭✭✭✭
    Re: Solar panels with no exposed metal.
    lay them on a roof perhaps with some ballast?

    Cariboocoot and John P have laid out the stark truth on the panels being considered, so I'll leave that as it is. However, on another thought - - regardless of the panel type, just laying them on the roof with no air cooling ventilation space behind them (roughly 4 inches) will lead to the panels really overheating and the drop off in power production that goes with hot panels. Something to keep in mind for the future.
    And please don't feel "jumped on", as we are only trying to save you grief and money, and hopefully point you in directions that work. You came to the right form for excellent, honest advice and we wish you well in you're quest for green energy.
  • stephendvstephendv Solar Expert Posts: 1,571 ✭✭
    Re: Solar panels with no exposed metal.
    Cariboocoot and John P have laid out the stark truth on the panels being considered

    I'll have to differ with the other opinions offered above. Here's another:

    Modern thin film panels come with the same warranty as do poli and mono panels. There are a raft of different technologies that are all called "thin film", e.g. amorphous silicion, CdTe, micromorph silicon and CIS. A company called First Solar which was the second largest manufacturer of solar panels worldwide, makes CdTe panels exclusively. They are also frameless.

    Rather than continuing to tarnish all thin film technologies ever produced (and all thin film that will ever be produced) with the same brush because of a few miss-steps in the technology's early days- I'd say you need to look at the specific module and manufacturer's history. I've never heard of "abound" solar panels, but CdTe as a technology is certainly well proven. You're taking a risk with an unknown manufacturer when well known brand polis can be had for a few cents more.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Solar panels with no exposed metal.

    They still do not produce like crystaline panels so you still need significantly more space for the same Watts.
    If you do a search on this site for "thin film" you find mostly news articles about the companies; technology "advances" (good luck finding them in the actual marketplace) and failing/failed companies. Not a good sign.

    Also we must note that the particular vendor linked to has not had the best reputation for customer service. Let's leave it at that.
  • rollandelliottrollandelliott Solar Expert Posts: 834 ✭✭
    Re: Solar panels with no exposed metal.

    I'd be interested in learning how you plan to just Lay them on your roof?
    any balast, even if 1" high will create shadows on the panels early and late in the day.

    schletter makes clamps specifically for frameless panels.

    thin film requires around 2x the space and thus 2x the mounting costs. so by the time you add 25cents/2 per watt =12.5 cents/watt you get panels for 62cents a watt.

    I saw some on sale for 69 cents a watt with aluminum frames last week.
  • john pjohn p Solar Expert Posts: 814 ✭✭✭
    Re: Solar panels with no exposed metal.

    Stephendv. I get to see and test just about every new type of panel ,inverter and charge controller that is about to possibly be marketed or has just been marketed. I have as yet never come across a "thin film" panel of any type from anyone that even came close to its rated figures. And if used in the same way as normal glass covered cells with aluminium frames they dont last a year without the output reducing by at least 1/3rd.

    If you have other experiences with them that proves they are good and long term (5 yrs) do put out the same or almost the same please tell us about them.
    Im not interested in manufacturers claimed results.Only results that are proven in actual use,.
  • BB.BB. Super Moderators, Administrators Posts: 30,640 admin
    Re: Solar panels with no exposed metal.

    John,

    Supposedly--The thin film panels would stabilize at ~80% of their initial output (after a couple months) and then age the balance of their life similar to crystalline panels (~1% per year).

    Have you done enough testing to prove or disprove that claim?

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • john pjohn p Solar Expert Posts: 814 ✭✭✭
    Re: Solar panels with no exposed metal.

    BB what we do is in simple terms.speed up the aging process.Its done by cycling them through heat,cold and water 24hrs a day non stop. It is a fact that this method is not perfect but is does give very close to the results where real time testings is done.
    Obviously a manufacturer that gives us a new product to test cant wait 10 yrs to get the results.!!!!!
    Every type of thin film panel has its output drop to about 70% at end of accelerated aging. Not like the manufacturers claim.
    Now the really bad news.
    At the end of 5yrs accelerated aging they just start disintegrating. First they discolour badly. And output drops to about 50%.
    About 4 yrs ago now we did mount some on the roof. Our roof gets to about 60deg C in summer. First the panels dont stay flat when mounted,they buckle.
    After two yrs ALL the panels had some defect that stopped them working completely. Im not joking.It really happened like that.

    It really appears they are ment for occasional use like I said for campers and hikers. Then they are good as very light and hard to damage. And more importantly they are in the hot sunlight usually on the ground and NOT on a hot roof. It makes a huge difference to how long they last.

    I honestly could not recommend them to be used in a permanent situation..

    As I said if someone else has actually tested them on a roof or anywhere long term please post your findings here.
  • john pjohn p Solar Expert Posts: 814 ✭✭✭
    Re: Solar panels with no exposed metal.

    BB for obvious reasons I cant name the manufacturers or distributors of any of them,, But will say this.. Without exception none of them are good with warranties on them.. They all use every excuse under the sun(pun intended) to not replace them.

    If you think about them its a mounting problem mostly. As they are flexible its not easy to mount them clear of the roof so there is airflow under them. They usually just sit on the hot roofing iron sucking up the heat. and its just beyond the capabilities of the material to survive that day after day.

    If you are going to make frames or something to sit them on you may as well have bought panels already made like that..
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Solar panels with no exposed metal.

    Given the 20% expected degradation and the lower efficiency to begin with, it looks as though you'd need to plan on 220% more space for the same 'real' Watts.
    Not such a great deal, then.
  • stephendvstephendv Solar Expert Posts: 1,571 ✭✭
    Re: Solar panels with no exposed metal.
    john p wrote: »
    If you think about them its a mounting problem mostly. As they are flexible its not easy to mount them clear of the roof so there is airflow under them.

    Am I working to a different definition of "thin film" than you chaps? All the "thin film" panels I know are glass covered panels with or without frames. When you say "thin film" do you mean _flexible_ thin film panels?

    For real world comparison you can choose which panel technology to compare from a drop down list on this form: http://www.solar-yield.eu/free-photovoltaic-comparison-seach.html

    Some examples:
    http://www.solar-yield.eu/en/gablingen/solarbooster/2810/2727.html
    http://www.solar-yield.eu/en/ilmenau/ik-1/14701/16967.html
    http://www.solar-yield.eu/en/jevenstedt/jevsol/367/218.html
    http://www.solar-yield.eu/en/waldalgesheim/waldalgesheim/2483/15728.html

    "Thin film" is a popular choice for solar farms too. The engineers who designed multi-mega watt power stations based on thin film couldn't all have got it wrong surely!

    http://en.wikipedia.org/wiki/Waldpolenz_Solar_Park
    http://en.wikipedia.org/wiki/Topaz_Solar_Farm
  • nielniel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Solar panels with no exposed metal.

    unisolar i can name as one without glass.
  • john pjohn p Solar Expert Posts: 814 ✭✭✭
    Re: Solar panels with no exposed metal.

    Well it seems im on the wrong train.
    Sorry folks .
    I should have thought about it better. I never got past only thinking about when the first post asked about putting some ballast on the panels to hold them down,and it seemed others were only talking about how they sat flat on the roof.
    It seems we have a much narrower view of what "thin film" panels are here.
    Stephendv what you posted what they are calling thin film makes you correct about those panels. Here we group that type of panel into the same group as your "normally" available aluminium framed glass panels.
  • MPaulHolmesMPaulHolmes Solar Expert Posts: 35 ✭✭
    Re: Solar panels with no exposed metal.

    I didn't mean ballast on top of the panel. Perhaps weighing down the underside somehow. So, the thin film panels that are known to be lousy and die after maybe 5 years, are these them?
    http://www.sunelec.com/Specs/Abound%20AB-1.jpg

    Are there any brands of panels that don't have to be grounded that are also good quality?
  • rollandelliottrollandelliott Solar Expert Posts: 834 ✭✭
    Re: Solar panels with no exposed metal.

    all panels should be grounded and it's pretty cheap to do so.
    even the laziest inspector is going to notice a ground wire missing.
  • MPaulHolmesMPaulHolmes Solar Expert Posts: 35 ✭✭
    Re: Solar panels with no exposed metal.

    How do you ground a panel that consists only of glass in the front and glass in the back, with no frame? I'm referring to this article:
    http://www.technologyreview.com/news/428423/new-solar-panel-designs-make-installation-cheaper/

    Specifically, this part:
    While Trina modifies the solar panel's metal frame, Solon eliminates it altogether. It takes an array of solar cells that have been sealed behind a layer of glass and then glues that to a plastic form that angles the cells toward the sun. This complete module is assembled in a factory, reducing the amount of work that needs to be done on site. Installers set the modules on the roof, link them together with plastic connectors (they also add some ballast), and plug wires together to establish electrical connections. Because the modules have no exposed metal, it isn't necessary to ground them, which helps reduce costs. Solon says the design reduces the time needed for mechanically mounting the panels by 75 percent, and the time needed for making the electrical connections by half. (Solon says that the impact on costs varies widely, depending on factors like labor costs.)
  • stephendvstephendv Solar Expert Posts: 1,571 ✭✭
    Re: Solar panels with no exposed metal.

    You'll have to check the module datasheet to see whether it requires grounding or not. FirstSolar panels which are also frameless don't require it: http://www.belectric.com/fileadmin/DE/en/pdf/datasheet/First_Solar_Datasheet_FS_Series_3.pdf

    If this is the company that manufactures those panels you listed then say goodbye to the warranty: http://www.abound.com/abound%C2%AE-solar-suspend-operations

    EDIT: Since they're bankrupt you'll also have a problem recycling the toxic cadmium modules at the end of their life. FirstSolar, which also uses Cadmium, have a program where you can return the modules to them free of charge so that they can safely dispose of the cadmium.

    The installation manual is here: http://www.abound.com/sites/default/files/Abound%20Safety%20and%20Installation%20Manual.pdf they do require a negatively grounded system with a transformer based inverter, (the negative grounding is done in the inverter) so you don't have the option of using the higher efficiency transformerless ones.
  • BB.BB. Super Moderators, Administrators Posts: 30,640 admin
    Re: Solar panels with no exposed metal.

    Remember, in the case of the frames and the racking, you are grounding large pieces of metal to avoid them becoming "hot" from a shattered panel or failed wiring.

    Even if there is no metal frame, I would presume that the metal racking to hold the "frameless" panels would still need to be grounded. This would also help in the case of lightning strikes.

    Then there is the issue of grounding the panel itself (negative or positive grounding). In most cases, grounding is not required for proper panel operation (Sun power panels from Germany, require positive grounding to prevent charge build up which reduces panels' output power).

    However, earth grounding/reference is typically used as part of an overall safety system. Ground referencing can prevent static voltage build up (natural electric field of the earth of ~100 volts or so per meter). And dissipate lightning based static build up and (to a degree) strike energy).

    Also, "hard grounding" a return line (negative ground to battery bank, AC white/neutral wire to ground) allows us to use fuses/breakers only on the "hot leads" as there cannot be any excessive current flow in the return leads if they are properly designed as a "short to ground" will not cause very much current to flow (common method of grounding North American homes with 120/240 VAC split phase wiring).

    It also can help reduce the chance of over voltage on your AC wiring (or even DC wiring on the roof of a building) if there is a distribution wiring cross with your home's wiring (such as wiring from your power pole falling across your panels if a car strikes the pole).

    There are lots of reasons for grounding and a few good reasons to not ground reference a power system (you cannot get a shock to earth with a floating power system as an example).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • rollandelliottrollandelliott Solar Expert Posts: 834 ✭✭
    Re: Solar panels with no exposed metal.
    schletter makes clamps specifically for frameless panels.

    http://www.youtube.com/watch?v=IpcYxDAP8Y4

    see timeline at 2:15

    some rubber and aluminum is all you really need.
  • ggunnggunn Solar Expert Posts: 1,973 ✭✭✭
    Re: Solar panels with no exposed metal.

    There is grounding and then there is grounding.

    The ECG (Equipment Grounding Conductor) is required by the NEC for any exposed metal that may become energized either by the components they house or by external sources, such as lightning. Frameless modules are not required to be connected to the ECG (in fact it is not possible), but any metal racking supporting them is.

    Many PV systems (most of them at present) additionally have one of the DC conductors (usually the negative) for each string connected to ground through a ground fault detection/interrupt device, which is often inside the inverter. This is a completely separate issue and has nothing to do with whether the modules have frames or if they are thin film.
Sign In or Register to comment.