Solar Panels- Polycrystaline or Monocrystaline?

[SV Demeter]

So Ive been searching for solar panels which will give me the most juice for the footprint I have to work with. (Roughly 40" x 26") It seems like these 100 watt panels will do the trick. Solar Panel 100 Watt 12 Volt - SPM100P-TS

Seems like anything higer wattage takes me to a larger frame size. SO my question is are polycrystaline panels okay or should I be trying to find monocrystaline panels?

FWIW I emailed the folks at solartech and asked if their panels were suitable for use in a marine environment and they said yes. They also quote me $395 ea for the abovementioned panels. Im thinking of ordering 4.

[callmecrazy]

Mono panels are more efficient on a per-cell basis. So the are often a little smaller than poly for the same output.

But for panel vs. Panel, they will both produce whatever they're rated for.

So if you want a smaller form factor, or if you if you want more wattage for the size of the panel, look into mono.

But if they fit your mounting option and output what you want, it realy doesn't matter.

[SV Demeter]

Originally Posted by callmecrazy

Mono panels are more efficient on a per-cell basis. So the are often a little smaller than poly for the same output.

But for panel vs. Panel, they will both produce whatever they're rated for.

So if you want a smaller form factor, or if you if you want more wattage for the size of the panel, look into mono.

But if they fit your mounting option and output what you want, it realy doesn't matter.

So that makes me think I should be able to find a higher watt panel that will fit in my footprint? It seemed like 100 watts was the max I could find in a 40x26 panel but maybe I'll keep looking. Also noticed mono panels seem a lot more expensive. Is it worth it?

[Sea Yawl Later]

Ive got the predecessor to these:

Kyocera KD135GX-LPU Solar PanelMax Rated Power (Pmax)135 WattsVoltage at Max Power (Vmpp)17.7Current at Max Power (Impp)7.63 AmpsOpen Circuit Voltage (Voc)22.1Short Circuit Current (Isc)8.37 AmpsLength x Width x Depth (inches)59.1 x 26.3 x 1.8Weight of Panel (Pounds)28.7

My panels have lasted very well and do a good job, My boat came with the earlier model that makes 120 watts, these are a bit better. I found them online for 330 each, might find a better price than that if you check around.

Kyocera KD135GX 135 Watt 12 Volt Solar Module

I see due to your length restriction, these might not fit, if they do I like mine.

[callmecrazy]

The efficiency difference isn't that much, going up a panel size might be your only option to get more wattage in this case, but look around. I'm not sure how that all works, but I've seen similar sized panels with 30watt differences, I've also seen two similar sized mono's with very different wattage, so it all gets pretty confusing after a while. Just get whatever fits

Emaineinc.com has a 135watt kyocera for $375 (59x26"). $385 doesn't sound like a good deal for 100 watts. But I haven't done any panel shopping in several months...

[callmecrazy]

Even better...

[SV Demeter]

Originally Posted by callmecrazy

The efficiency difference isn't that much, going up a panel size might be your only option to get more wattage in this case, but look around. I'm not sure how that all works, but I've seen similar sized panels with 30watt differences, I've also seen two similar sized mono's with very different wattage, so it all gets pretty confusing after a while. Just get whatever fits

Emaineinc.com has a 135watt kyocera for $375 (59x26"). $385 doesn't sound like a good deal for 100 watts. But I haven't done any panel shopping in several months...

Yeah I was not thrilled with the $385 price tag. I initially wanted to go with 135 watt Kyoceras but my mounting solution wont tolerate that long of a panel. I need to keep the panel length down closer to 40". In looking at panels in that length I could not find anything over 100watts.

[noelex 77]

Monocrstalline cells are slightly more efficient, but take up a bit more space so when packed into panel the efficiency is very similar. Its easy to calculate the efficiency just divide the watts by the area to compare.
Its also worth looking at the number of bypass diodes the reduction in panel output with temperature. The later is important because panels are rated at 25 deg c, but will usually operate at around 40 deg
.