What is What

[thirteen]

Would someone explain the difference between Monocrystal solar panel and a Polcrystalline solar panel. Same company same advertisement.

[SparWeb]

I've seen this done.  They use the same frame, wiring, and same datasheet format.  But one panel is made from mono crystal wafers and the other panel is made form poly crystal wafers.  That's why you have to read the datasheets carefully.  Mono panels are more expensive, generally, I believe.

Because the crystal structure is different, the ratings change slightly, and so do the details like thermal gradient factors.  Monocrystals look like one continuous sheet of dark blue, while polycrystals have a patchy look, which is easiest to see when you shine light on it at an angle.

[wpowokal]

Google does this best but just one of squillions of hits....

Monocrystalline–

- Highest power to size ratio: efficiency typically within the range of 135-170 Watts per m2 (13-17%, with notable exceptions).

- Outstanding performance in cooler conditions.

- Some leading units now have over 18% conversion efficiency (best in Australia).

- Most widely used in the world, with over 50 years of technological development.

- Excellent life span / longevity. Usually come with a 25yr warranty.

- Best option if you have limited space on your roof.

Polycrystalline

- Good efficiency: typically 120-150 Watts per m2 (12-15%, with notable exceptions).

- Marginally less expensive than monocrystalline.

- Excellent life span / longevity. Usually also come with 25yr warranty.

- Ideal for small to medium sized rooves.

Amorphous Thin Film

- Lowest efficiency: typically 60-80 Watts/m2 (6-8%, with notable exceptions).
(Edited, RossW: 60-80% was clearly a typo!)

- Expected lifespan is less than crystalline panels.

- Optimal efficiency in hot weather, less effective in cooler conditions.

- 3-6 month ‘breaking in' period where long term output is exceeded.

- Requires 2-3 times more panels and surface area for same output as crystalline.

- Ideal for example for inland Australia, where conditions are hot and vacant space abounds.

[ghurd]

Mono can also look like brown wafers (NOT brown stripes the length of the PV).
Poly looks like blue cracked ice.
Amorphous Thin Film looks like brown stripes.

I am not so sure I belive some of the mono sales pitches, "more efficient use of available space", etc, because I have used 75W monos the same size as 85W polys.
G-

Edit-  Typo fixed

[Norm]

what type are the panels 45 watt that HF sells ?
I heard that they lose their efficiency after a few years.
Norm.
BTW The pedaler on the pedalgen is losing his efficiency
too after 80 years....

[ghurd]

The 45W 'kit' HF sells is Amorphous Thin Film.
Look close, and they have brown stripes running all the way across them.

"BTW The pedaler on the pedalgen is losing his efficiency
too after 80 years.... "
Did you switch to decaf?
Decaf reduces efficiency!
G-

[Mary B]

After 2 years out of 6 harbor fright panels one had died completely(water had made it behind the aluminum frame and froze and broke the connections at the top), 3 more had the junction boxes fall off and all that still worked were down in output.

[Rover]

I can also describe failure of HF panels.... after 4 years.. the full set was shot...looked like water ingress

Back then was a cheap way to get panels, now... wouldn't even think about it.

[wpowokal]

Mine are CNPV Nono panels, they work well in low light, very good for the tropics, it is 0745 Hrs and there is 1.5+ Kw coming in, the sun is still low in the sky and enough cloud that I can comfortably look directly at it. They have only been installed for 6 months so I can not attest to their longevity but the installer lives in the area and I trust his experience.

In the time it has taken me to type this the clouds have moved and there is 4.7 Kw coming in.

Allan of the jungle