Unisolar panels.....comments.....???
sno
I have been thinking of purchasing some unisolar panels.....
they seem to be among the least expensive per watt....and
appear easiest to install....(glue to roof)
Would like to know if anyone has had any experience with them
and any comments pro or con....
thanks for your help......sno
--
Correct Scientific Terminology:
Hypothesis - a guess as to why or how something occurs
Theory - a hypothesis that has been checked by enough experiments
to be generally assumed to be true.
Law - a hypothesis that has been checked by enough experiments
in enough different ways that it is assumed to be truer then a theory.
Note: nothing is proven in science, things are assumed to be true.
BobG
> I have been thinking of purchasing some unisolar panels.....
Are they monocrystalline like real silicon wafers from diffusion
furnaces, or polycrystalline (less efficient but cheaper)?
sno
Here is a quote from this page which explains the type of panels...
United Solar Ovonics manufactures modules using a-Si/a-SiGe/a-SiGe
triple junction cell. Amorphous cells with different light absorption
properties deposited continuously, one on top of another, to capture the
broad solar spectrum more effectively. This increases the energy
conversion efficiency of the multi-cell device and improves performance
stability. In other words their structure enhances the ability of the
cell to absorb different wavelengths of light and helps stabilize the
cell in regard to the SWE effect
http://thefraserdomain.typepad.com/energy/2005/08/about_amorphous.
Polycrystalline....???
thanks for any comments info.....have fun.....sno
Mauried
Id stay away from amorphous cells currently, until there is a lot more
data available on their reliability.
Both mono and polycrystalline solar cells have been around for many
years and their reliability characteristics are well known.
They are also made by well known companies who have been in the
business for many years.
sno
These people have been around since at least the early 90's....
used their solar strips....(hard to call them panels)....while
in the military....was impressed at the time how you could roll
them up and carry around....seemed impossible to harm them in
any way....just wipe them off and away they went....
They have been selling to the government since at least that time
their old ones were not as efficient....do not know if they have
any figures on their newer ones....the government still buys from
them so they must be working as advertised.
If you have ever seen those roll up auto trickle battery chargers
that you put in the cars window...then you have seen them....
they were first put out for that purpose...
Mauried
Portable applications such as roll out solar strips are not the same
as solar panels on a roof where the panel is continuously exposed to
the sun and to heating and cooling cycles.
Most amorphous solar panels in the past used in rooftop applications
have poor reliability records due to the heating cooling stresses
causing the thin films to break.
None of th major Solar panel companis such as Sharp, Kyocera,
Sunpower, BPsolar make amorphous panels for roofops.
You might wonfer why not if they are cheaper to make.
sno
> On Sat, 03 Oct 2009 00:17:46 -0400, sno <s...@opelc.com> wrote:
>
>> Mauried wrote:
>>> On Fri, 02 Oct 2009 21:56:56 -0400, sno <s...@opelc.com> wrote:
>>>
>>>> BobG wrote:
>>>>> On Oct 2, 2:36 pm, sno <s...@opelc.com> wrote:
>>>>>> I have been thinking of purchasing some unisolar panels.....
>>>>> ==============================================
>>>>> Are they monocrystalline like real silicon wafers from diffusion
>>>>> furnaces, or polycrystalline (less efficient but cheaper)?
>>>> Here is a quote from this page which explains the type of panels...
>>>>
>>>> United Solar Ovonics manufactures modules using a-Si/a-SiGe/a-SiGe
>>>> triple junction cell. Amorphous cells with different light absorption
>>>> properties deposited continuously, one on top of another, to capture the
>>>> broad solar spectrum more effectively. This increases the energy
>>>> conversion efficiency of the multi-cell device and improves performance
>>>> stability. In other words their structure enhances the ability of the
>>>> cell to absorb different wavelengths of light and helps stabilize the
>>>> cell in regard to the SWE effect
>>>>
>>>> http://thefraserdomain.typepad.com/energy/2005/08/about_amorphous.
>>>>
>>>> Polycrystalline....???
>>>>
>>>> thanks for any comments info.....have fun.....sno
>>>>
>>>
>>> data available on their reliability.
>>> Both mono and polycrystalline solar cells have been around for many
>>> years and their reliability characteristics are well known.
>>> They are also made by well known companies who have been in the
>>> business for many years.
>>>
>> These people have been around since at least the early 90's....
>> used their solar strips....(hard to call them panels)....while
>> in the military....was impressed at the time how you could roll
>> them up and carry around....seemed impossible to harm them in
>> any way....just wipe them off and away they went....
>>
>> They have been selling to the government since at least that time
>> their old ones were not as efficient....do not know if they have
>> any figures on their newer ones....the government still buys from
>> them so they must be working as advertised.
>>
>> If you have ever seen those roll up auto trickle battery chargers
>> that you put in the cars window...then you have seen them....
>> they were first put out for that purpose...
>>
>> have fun.....sno
>>
>
>
> as solar panels on a roof where the panel is continuously exposed to
> the sun and to heating and cooling cycles.
> Most amorphous solar panels in the past used in rooftop applications
> have poor reliability records due to the heating cooling stresses
> causing the thin films to break.
> None of th major Solar panel companis such as Sharp, Kyocera,
> Sunpower, BPsolar make amorphous panels for roofops.
> You might wonfer why not if they are cheaper to make.
>
patented the technology for nickle metal hydrid batteries...they get a
cut from every battery sold....they also hold the patent for the
amorphous unique thin panel technology....they have been selling mainly
to large installations and have not done much in the home market.
Here are some archived reports where you can see where they have been
selling....since the own the patent no one else can use their technology...
Actually they stand up to thermal stress better than normal
panels....and their is less efficiency loss do to high heat..
http://www.uni-solar.com/interior.asp?id=62
I have studied their panels pretty closely...and think I have all the
answers...<grin>
Was hoping someone had some actual experience with their panels...who
could comment.....as a final check....
Looks like if things work out may be the first to report....in ten years
or so....<grin>...if I am still around....
thanks again...have fun....sno
sno
50's....(just found it)
Their panels were on the MIR space station....!!
http://www.ovonic.com/fo_ecd_ovonics_history.cfm
have fun....sno
Ecnerwal
sno <s...@opelc.com> wrote:
> I have been thinking of purchasing some unisolar panels.....
> they seem to be among the least expensive per watt....and
> appear easiest to install....(glue to roof)
I'd be very surprised if they were low cost, as they have always been
overpriced relative to crystalline cells, despite claims that they could
be made ever so inexpensively.
The lowest cost I see for them is around $4/watt, and I don't know the
seller I found that at (ie, if they are a reputable dealer.)
Reputable dealers are selling crystalline cells at $3-3.50/watt. Some of
those reputable dealers used to sell unisolar and don't any more, which
might or might not indicate anything.
They are low power density - ie, for a given area covered with panels,
they make relatively little power - not a particular concern if you have
lots of space and no need for maximum power out of it.
If your roof is not standing seam metal in good shape, expected to last
50 years or so, you'll eat a fairly large cost when you have to re-roof
and find that your roof applied panels don't peel back up intact. And I
don't think it actually sticks to any other roof surface reliably.
--
Cats, coffee, chocolate...vices to live by
sno
about.....my present roof covering is a membrane....roof is fairly
flat...about five years old....is something will have to think about.
Maybe can find a long lasting adhesive that will work...that somehow
can be softened to remove panels....something I have to check on...
I have found them on web in the area of 3.50 watt....and think with the
present decline in sales they and others are experiencing (large solar
projects not being able to get funding at moment)....that should be able
to get them at lower price then that.....looking on the web, production
is being cut back all over.
I think the reason they have had trouble selling to the home consumer is
their look.....putting this floppy sheet next to a super nice looking
box that is five or six times the weight of the sheet and looks like it
will last forever.....and then telling the customer the sheet will
produce almost as much power as the box over its lifetime makes it a
hard sell....
Also if you are a installer....which one will you make the most money
installing....??......a couple hours slopping down some glue....or a
couple days drilling mounting holes and assembling mounting
brackets...and installing.......
They seem to have no problem selling to corporations....probably because
a corporation will hire a solar engineer to look over the product....and
corporation could care less how they look.....as long as they work as
advertised. Another advantage to corporation is not having to mess with
after installation....no worry about wind damage....hail damage.....or
excess weight on roof structure......no holes/minimum leaks....
I had realized that they will take up a little more area then box panels.
Anyway thanks for bringing up reroofing....
have fun.....sno
Martin Riddle
"Mauried" <mau...@tpg.com.au> wrote in message
news:4ac6ca99....@news.tpg.com.au...
I'd stay away from Ovonics too.
But I digress...
amorphous cell degrade rapidly and loose a large percentage of their
output vs mono or poly.
( I forget the exact amount but I believe its around 25% in 2-3 years)
Cheers
sno
they do say you can expect 10-15 percent over output initially....
maybe there is a large degradation for some reason when first
installed...?????....this is something do not know how to check
on unless someone with actual experience responds here....thanks
for your input.....
have fun....sno
ECDfan
dedicated to that fine company. Panel price per Watt is not a good way
to evaluate overall system cost (Unisolar's dismal 6.3%-efficiency on
module level will cost you 80c per Watt or so on system level vs
crystalline panels, and the laminates are harder to install than you
think). If that does not ruin you, the severe long-term degradation,
the underperformance due to suboptimal tilt, the heating-up the roof
due to lack of ventilation (increasing HVAC costs), and even the
propensity to ignite - those will finish you. Proceed with caution!
On Oct 2, 2:36 pm, sno <s...@opelc.com> wrote:
sno
has the real world information I was looking for....
Am a bit sorry that my research did not reveal all the things that
you blog talks about...but very happy that did not proceed without
posting here....
After reading your blog think I will hold off for a couple years to
see what happens in the PV field....maybe unisolar will come up with
fixes to their problems...<grin>
A little off topic....I assume your are an investor in Ovonics....I
have often wondered why their are no NiMH batteries available for
solar storage....happened in my research to run across this article
in wikipedia....do not know if you are aware of Ovonics problem with
large batteries....their patent being tied up by another company...
which seems to be capitalizing on them....
http://en.wikipedia.org/wiki/Patent_encumbrance_of_large_automotive_NiMH_batteries
Also, from what have read on your blog...how does a company that has
been around since the 60's and never made any money not go bankrupt...???
Again thank you for your great blog and responding here....have fun....sno
Mel
tilt angle, but alss don't forget that anything that is flat is no
longer self cleaning.
Mel
Martin Riddle
charge control, the Patent has since expired.
As a result you see more MPPT controlers on the market.
Cheers
"sno" <s...@opelc.com> wrote in message
news:4acd826c$0$77545$892e...@auth.newsreader.octanews.com...
ECDfan
you have the proper charge controller - but why would you go with the
expensive NiMH, when you can use cheap lead-acid? Anyway, NiMH
batteries are widely available on Ebay - AA (for digital cameras) and
Sub C (for Roomba) - just connect them in a series, if you like them.
The problem, of course is their self-discharge rate and poor
performance in low temperatures (which you can avoid if you buy the
much more expensive Sanyo's Eneloop or GP' ReCyko ones). As far as
batteries for hybrids are concerned, Ovonics' batteries suck. Their
JV Cobasys ruined the ENTIRE 2007 GM hybrid production by supplying
leaking batteries that were subject to a total recall. Ovonics is not
the victim here - it is Ovonics that unfairly exploited the patent
laws to extract millions from the companies who actually developed the
batteries, but, of course, that did not help them much in the end.
Yes, ECD is a unique company, draining cash for 49 years, mainly
because of the skills of their charismatic founder, the Charlatan
Extraordinaire Mr. Ovshinsky, who is no longer with the company. But,
remember, Madoff was able to defraud investors for 40 years, before
the truth came out.
On Oct 8, 2:11 am, sno <s...@opelc.com> wrote:
> WOW....thank you very much....your blog with real world examples
> has the real world information I was looking for....
>
> Am a bit sorry that my research did not reveal all the things that
> you blog talks about...but very happy that did not proceed without
> posting here....
>
> After reading your blog think I will hold off for a couple years to
> see what happens in the PV field....maybe unisolar will come up with
> fixes to their problems...<grin>
>
> A little off topic....I assume your are an investor in Ovonics....I
> have often wondered why their are no NiMH batteries available for
> solar storage....happened in my research to run across this article
> in wikipedia....do not know if you are aware of Ovonics problem with
> large batteries....their patent being tied up by another company...
> which seems to be capitalizing on them....
>
> http://en.wikipedia.org/wiki/Patent_encumbrance_of_large_automotive_N...