Amorphous vs Crystalline in Low Sun Areas

I live near Chicago and get very few sun hours in the winter and from what I understand, in cloudy weather, the crystalline panels are pretty much worthless whereas amorphous panels can get upwards of 50% capacity on overcast days. So even though amorphous panels are almost twice the cost, it seems they are way more cost effective at least for winter electricity (when I need it most) in cloudy climates. Am I thinking straight?

The other issue is mounting a laminate panel as I have a shingle roof. I'm very handy but don't want to end up with a nightmare install. So the other question is how difficult is it to install a laminate panel on a shingle roof?

Thanks for any insight.

Paul

Comments

  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: Amorphous vs Crystalline in Low Sun Areas

    I think you will find that the consensus favours conventional PV. Most claims of superior ef of the others are minimal at best.

    Given the cost, go with more conventionals, at less cost.

    Others may chime in differently,,,

    Tony
  • paullad
    paullad Registered Users Posts: 2
    Re: Amorphous vs Crystalline in Low Sun Areas
    icarus wrote: »
    Most claims of superior ef of the others are minimal at best.
    >Given the cost, go with more conventionals, at less cost.

    Tony,

    Most claims of who? Manufacturers or people that use the products? I'm not really that interested in what the mfg says. But the people that use them in cloudy areas I've talked to say there is no comparison on a cloudy day.

    Thanks,
    Paul
  • icarus
    icarus Solar Expert Posts: 5,436 ✭✭✭✭
    Re: Amorphous vs Crystalline in Low Sun Areas

    Try here to start: http://www.energymatters.com.au/renewable-energy/solar-power/thin-film-monocrystalline.php
  • Windsun
    Windsun Solar Expert Posts: 1,164 ✭✭
    Re: Amorphous vs Crystalline in Low Sun Areas
    paullad wrote: »
    I live near Chicago and get very few sun hours in the winter and from what I understand, in cloudy weather, the crystalline panels are pretty much worthless whereas amorphous panels can get upwards of 50% capacity on overcast days. So even though amorphous panels are almost twice the cost, it seems they are way more cost effective at least for winter electricity (when I need it most) in cloudy climates. Am I thinking straight?

    The other issue is mounting a laminate panel as I have a shingle roof. I'm very handy but don't want to end up with a nightmare install. So the other question is how difficult is it to install a laminate panel on a shingle roof?

    Thanks for any insight.

    Paul

    Both of those statments about crystalline vs amorphous are wrong. In order of how well they work in low light, it is Monocrystalline, Polycrystalline, and then amorphous (thin film).

    But the fact is, the difference is so minimal as to not make any difference - on the order of 2-6%. When you consider that "low light" - ie cloudy - equals about 1/10th to 1/100th of sunny solar power, and extra 5% of 10% or less is not much.

    If you are talking about the amorphous shingles, don't do it - it is basically an entire re-roofing + the panel cost
  • Thomas
    Thomas Solar Expert Posts: 291
    Re: Amorphous vs Crystalline in Low Sun Areas

    When I was shopping for panels I ran into some company advertizing low light panels that used a third bus bar on the cells, sacraficing the high end voltage but with signifigant improvement in low light. Any fact to it?
    Always troubleshoot with adequate sunlight.  Hi Ho Hi Ho
    2.3kW [10] Enecsys SMI-240-60 micro inverters

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Amorphous vs Crystalline in Low Sun Areas

    Don't know--But I would doubt that adding metal helps low power/low current that much (more metal would help higher current in full sun... But just guessing).

    My guess as to why people say Amorphous panels do so well in testing is that they are usually under rated. The first 6 weeks of sunlight will reduce the wattage for an Amorphous panel by ~20% or so... So, if you put new panels in, the system will do better than rated power for the first few months before the panels stabilize at the lower name plate rating (and, if I remember correctly, claim to loose ~1% a year after "burn in").

    A crystalline panel will loose 3% maximum in the first ~12 months, then loose something on the order of 1% a year after that.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Thomas
    Thomas Solar Expert Posts: 291
    Re: Amorphous vs Crystalline in Low Sun Areas

    I have heard and again from you that the amorphous, thin film is a kind of gimmick, though I did have a few deer feeder flex cell amorphous that if I still had I would make permanant duty cooling fans, they worked great in low light days with those computer cooling fans. I do not know if they would be any good at larger scale, they are very expensive though.
    Always troubleshoot with adequate sunlight.  Hi Ho Hi Ho
    2.3kW [10] Enecsys SMI-240-60 micro inverters

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Amorphous vs Crystalline in Low Sun Areas

    Amorphous panels are supposed to be be less expensive (they were supposed to be under $1 per watt a year or two ago)... Problem (for amorphous panel MFG'rs), crystalline panels dropped below $2 per watt (and getting close to $1 per watt).

    Other issue is that amorphous panels are about 1/2 the efficiency of crystalline panels--so you need 2x the square footage (and racking, wiring, etc.) for the same amount of power.

    If you are laying panels in an open field, a bit less of an issue. If you are placing panels on a roof--you may run out of roof space to build a large enough array to power your home.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Thomas
    Thomas Solar Expert Posts: 291
    Re: Amorphous vs Crystalline in Low Sun Areas

    I have noticed two markets of thin film/amorphous panels, for the shopper ,I think one is like sprayed on film and the other is a fine grit crystaline....like paste or something, I will stick to the mono/poly panels, At my budget I can't afford the mistake, even if the panels are more affordable.
    Always troubleshoot with adequate sunlight.  Hi Ho Hi Ho
    2.3kW [10] Enecsys SMI-240-60 micro inverters

  • Windsun
    Windsun Solar Expert Posts: 1,164 ✭✭
    Re: Amorphous vs Crystalline in Low Sun Areas
    BB. wrote: »
    Other issue is that amorphous panels are about 1/2 the efficiency of crystalline panels--so you need 2x the square footage (and racking, wiring, etc.) for the same amount of power.

    -Bill
    That is what is killing First Solar - and the stock (FSLR) - down now almost 75% from it's high. In 2007 when crystalline was selling for $4 a watt, their $2 a watt product was a big deal, and overcame the extra cost of mounting etc. But now even the better panels, such as Kyocera, we are selling some for around $1.60 a watt at retail.
  • stephendv
    stephendv Solar Expert Posts: 1,571 ✭✭
    Re: Amorphous vs Crystalline in Low Sun Areas

    Here's a handy page that compares the real output from a number of different panel types. http://www.dkasolarcentre.com.au/flash/graphing.html
    It's a bit fidgety to work around, but if you plot rain then click on the 'year' view, you'll see 2/11 to 4/11 being the wettest period.
    Attached are the results. Poly and amorphous thin film are close, but it could also be because amorphous behaves so much better in the heat (the site is in Auz, so Feb - April would be summerish).
    Attachment not found.
  • Windsun
    Windsun Solar Expert Posts: 1,164 ✭✭
    Re: Amorphous vs Crystalline in Low Sun Areas

    Interesting that #14 and #17 are so close, given that the Sanyo HIT hybrids are touted as being so much more efficient (and they also cost almost twice as much).
  • Thomas
    Thomas Solar Expert Posts: 291
    Re: Amorphous vs Crystalline in Low Sun Areas

    Let me see if I got this scale right, those decimal places represent 4-5 1000 kwhrs. my bill is ~40 dollars for ~400 of the same unit/scale ?
    Always troubleshoot with adequate sunlight.  Hi Ho Hi Ho
    2.3kW [10] Enecsys SMI-240-60 micro inverters

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Amorphous vs Crystalline in Low Sun Areas

    Take the Number of kWH per year and divide by 365 days:

    4,800 kWH per year / 365 days per year = 13.1 kWH per day

    Then divide by the size of the array:

    13.1 kWH per day / 3.5 kWH solar array (DC nameplate) = 3.8 kWH per day per 1 kW of solar panels

    This number also based on how sunny the installation is, fixed or tracking array, efficiency of the GT inverter, any down time, etc.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Thomas
    Thomas Solar Expert Posts: 291
    Re: Amorphous vs Crystalline in Low Sun Areas

    I am looking for a decimal orientation, my bill is .4 or .04 of the same scale as the 4.123Kwhr/Kw my 400 monthly fits where the .123 is, right?
    Always troubleshoot with adequate sunlight.  Hi Ho Hi Ho
    2.3kW [10] Enecsys SMI-240-60 micro inverters

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Amorphous vs Crystalline in Low Sun Areas

    You have to tell us your power costs... Something like $0.10 per kWH in your area?

    So, a 1kW array powering 4kWH per day would save you:

    4kWH per day * $0.10 per kWH = $0.40 per 1kW array per day in electrical savings

    Of course, everyone has different electrical plans and may pay different $$/kWH depending on time of day and season. My kWH pricing ranges from $0.09 to $0.30 per kWH, and if I used more electricity on summer afternoons, I could pay as much as $0.52 per kWH (last I looked).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Thomas
    Thomas Solar Expert Posts: 291
    Re: Amorphous vs Crystalline in Low Sun Areas

    metered charges/meter difference=.095kwhr
    22.48/215
    Always troubleshoot with adequate sunlight.  Hi Ho Hi Ho
    2.3kW [10] Enecsys SMI-240-60 micro inverters

  • kylew
    kylew Registered Users Posts: 15
    Re: Amorphous vs Crystalline in Low Sun Areas

    With the bankrupsty of Unisolar this year, their thin film panels are now about $1 per watt from closeout dealers. they are long and skinney with self-stick backing to apply verticaly on metal roofs. No rack needed. In areas of the midwest (MO) where it can be cloudy for several days at a time, and assuming the roof is built to the proper angle towards the sun, and assuming ther oof area is big anough to handle more than enough panel space, does it seem worth a $1000 gamble to try these? There seems to be a lot of marketing hype on the cloudy-day performance, but not much real world data. Does anyone know of any recent real experience/data on this? Any comments and experience would be much appreciated.

    thanks
    kyle
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Amorphous vs Crystalline in Low Sun Areas

    On a cloudy day, I see my system reduced to 50%, and even as low as 5% collected power (vs a sunny day).

    Even if you can get a 10% increase on a system during cloudy weather, the overall increase is still pretty small (i.e., 10% increase of a 30% collection day is only a 3% increase in power vs a full sun day).

    So, I would not pay a lot of money to get a hand full of percent increase in power in cloudy weather.

    Plastic panels (vs glass)--I am not sure I would see more than 5-10 years of full power production before they degrade (my two cents--I am not in solar power sales, installation, or mfg). In hostile climates (on a boat), probably more like a couple years of useful life.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • waynefromnscanada
    waynefromnscanada Solar Expert Posts: 3,009 ✭✭✭✭
    Re: Amorphous vs Crystalline in Low Sun Areas
    kylew wrote: »
    their thin film panels are long and skinny with self-stick backing to apply vertically on metal roofs. No rack needed.

    Can't help but wonder how long before the self stick backing degrades and the panels are "Gone With The Wind".
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Amorphous vs Crystalline in Low Sun Areas

    I can imagine an inspector looking at them and saying "Not fastened down, not grounded: fail."

    Also it should be noted that amorphous panels do not produce more power in diffused light conditions; their output simply does not fall off as much. Crystaline panels (particularly mono) rely on direct sunlight for maximum production. When the angle changes or the light is diffused the output drops. Because the amorphous panels receptors "point in all directions" their output isn't as affected by these changes in light. However, since its less than half a polycrystaline panel's to begin with it isn't that great. You still need twice as much panel to begin with.

    I not saying they aren't any good, I just don't want people thinking if they buy amorphous panels they'll get full Wattage rating all the time.
  • john p
    john p Solar Expert Posts: 814 ✭✭✭
    Re: Amorphous vs Crystalline in Low Sun Areas

    The arguments about amorphous panels being superior in cloudy conditions is mostly myth. It is true they will produce about 5% more in VERY LIGHT CLOUD CONDITIONS but EXACTLY the same as other panels do under heavy cloudy conditions.. Its simple if heavy rain or heavy cloud there simply isnt any useful sunlight to convert to electricity. Much the same reason no panels produce any usable power at night time.DOH.

    Any salesman that tries to say otherwise is a crook. THE END
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Amorphous vs Crystalline in Low Sun Areas
    john p wrote: »
    The arguments about amorphous panels being superior in cloudy conditions is mostly myth. It is true they will produce about 5% more in VERY LIGHT CLOUD CONDITIONS but EXACTLY the same as other panels do under heavy cloudy conditions.. Its simple if heavy rain or heavy cloud there simply isnt any useful sunlight to convert to electricity. Much the same reason no panels produce any usable power at night time.DOH.

    Any salesman that tries to say otherwise is a crook. THE END

    Yep. Like the ever-persistent claims about panels that "Works in all weather conditions - even on cloudy days" (direct quote from an ad). Technically they put out power, but it's not necessarily a usable amount. The difference between the two panel types would be in the shape of the output bell curve over time: the amorphous is 'flatter'. Most of us in fact have seen this evening-out of production with crystaline panels on the 'right kind' of cloudy days: doesn't meet full power output ever, but is more consistent through the day. Sometimes you end up with higher total Watt hours than normal as a result! But there are so many variations on "cloudy day" that it's nothing you want to rely on.

    That's how the best scams work: take a little bit of scientific fact and twist it 'round to mislead the consumer.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Amorphous vs Crystalline in Low Sun Areas

    i know many are looking for a deal on pvs, but i would pass on the unisolars at $1/w as a few cents more/w in many cases can get you a good pv that will have better output years down the road and won't take up as much room as the unisolars. of course you would have to buy mounts, but, as was said already, i wouldn't count on the sticky backing adhering for very long on most roofing materials anyway. now if they were $.50/w then maybe think about it.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Amorphous vs Crystalline in Low Sun Areas

    Some of those Unisolar panels have some pretty weird Voltage/current output that makes them difficult to wire in to a typical system too.