multicrystalline vs polycrystalline?

mike49

Curious - is this kind of light blue panel with many large "flakes" all over it - is it what is referred to as "multicrystalline" polycrystalline?
http://www.123rf.com/photo_27734440_polycrystalline-solar-cell-3x6-for-diy-solar-panel-isolated-on-white-background.html

Up until now, I've only seen in real life polycrystalline panels that have been a more uniform darker blue like this:
http://www.123rf.com/photo_37101599_solar-cell-close-up.html?fromid=NVlwc2prUXd2UVh0QUdqM0Z5OTJPdz09

In the wikipedia article for polycrystalline, it has a similar picture of the light blue panel with many large "flakes" and calls it "multicrystalline":
https://en.wikipedia.org/wiki/Polycrystalline_silicon
and it says "While polysilicon and multisilicon are often used as synonyms, multicrystalline usually refers to crystalls larger than 1 mm."
But those flakes are way larger than 1mm, more like several centimeters/inches in diameter for many of the flakes...

Would this kind of light blue many large flaked panel (if it is called a "multicrystalline panel"?)
be a lower grade/lower performing/less durable panel compared to the more uniform darker blue kind?
Or is it just cosmetic and polycrystalline is polycrystalline?

I suppose the added bonus of this kind of panel, if it ever stops being useful as a solar panel,
is that it could be hung in one's geeky living room as abstract modern art/mural

BB.

Me personally, I see multi-crystalline and mono-crystalline as the same. Mono panels are a bit more efficient and are slightly smaller in area vs the same wattage rating.

Some folks here have said that Mono-Crystalline panels work a bit better in cloudy weather.

-Bill

Dave Angelini

And better in the desert or high temperatures.

softdown

Thought I read that mono panels degrade significantly slower.

mike49

Hi again, I was actually wondering if there were any differences in terms of quality / performance / longevity between these 2 kinds of POLYcrystalline panels?

1) polycrystalline but very light blue with lots of "flakes" all over the panel (I think this one is called "multicrystalline"?):

 
2) polycrystalline - darker blue, more uniform solid blue colour:


thanks for your thoughts...just going by looks, seems like #2) is higher quality? at least better looking, but does it degrade less or perform better than flakey #1)?

zoneblue

I didnt think that was any difference between multi and poly. Same same?

westbranch

here is a interesting read...http://energyinformative.org/best-solar-panel-monocrystalline-polycrystalline-thin-film/

mike49

Well, after much googling, this is the best info I could find about those light blue flakey polycrystalline panels:

http://skypoweraz.com/2010/12/whats-the-deal-with-the-pretty-blue-solar-panels/

Seems like they are an older style polycrystalline, that's why newbie me has never seen them before...

Dave Angelini

Buy Mono !  They have always been exceptional and excel in hot summer temperatures!
 Probably not a problem though in Toronto...

mike49

But the light blue flakey is...so...mezmorizingly....purdy.....

And now that I know that they're not too common anymore...
I couldn't pass up the opportunity to snag up a used one to add to my little collection

And just in time for testing under the 1st full clear sky sunny day in months around here!!

It's a 100w light blue flakey multi/poly, not that old actually, I'd say less than 5 years old since it has factory installed MC4 connectors and looks as modern in all physical aspects as my two 100w mono panels.

Based on my initial testing today under 11am full sun and downright balmy -8C (20F), side by side, it seems identical in performance to my 100w mono panels. Both were getting me 4.1A via pwm, which is as good as it gets under my setup/location/season.
The only difference I could see was that the multi/poly had an higher actual voc of 23.2v compared to my mono's 22.1v.

Here the the specs from the back of the panels:

100w old style multi-poly:
Vmp 19.2v Imp 5.23a Voc 22.68v Isc 5.6a
size: 1.0m x .668m = .668m2, weight: 8kg

100w mono:
Vmp 18.2v Imp5.5a Voc 22.7v Isc 5.89a
size: 1.2m x .54m = .648m2, weight: 7.8kg

So from what I can tell so far, there is no practical difference in any aspect between my 100w mono and 100w old style multi/poly for my little setup. Practically same size, weight, performance...and I like my shiny blue flakey toy...my...preciousssss...

Now I'm just hoping the Mrs won't notice the new wall art one day