mono vs poly real life testing

I went with what the dealer sold me and didn't know any different! Turned out to be Samlex Poly's for 150w @ $500.00 each. They work fine, but surely I could have done my self better for the $1650.00 I have invested in the 3 panels and the wimpy 30a PWM charger. I knew no better at the time, but I know better now, and it'd be best if others learned from my errors.

They went to 36 cells to get the voltage into the 14s to charge batteries properly, where the 33 cell ones could not. They still have an issue with 60 cell panels vs 72s when doing 24v.

jimindenver was the member who showed poly was better in low light and shoulder hours ISTR.

Lwiddis wrote:
Red, they all rated 100 watts. Poly is supposed to be more efficient. Mono needs three more cells to “make” 100 watts. Test didn’t show more efficiency.

then why were the poly 36 cell and mono 33 cell???
the fles was 32 cell!

As a pwm user in hot weather, the Vmp is important.

Lwiddis wrote:
Red, they all rated 100 watts. Poly is supposed to be more efficient. Mono needs three more cells to “make” 100 watts. Test didn’t show more efficiency.

But it does show more output in watts from poly vs mono unnder all the tested conditions.

3 tons wrote:
“ The mono is better for RV use. Mono should be more efficient. In reality there is minimal difference, but I spring a few bucks extra always for the mono.”

Agreed, but this additional efficiency manifest itself via a smaller footprint - regardless of which substrate, 100w is still 100w, thus I find the panel presenter’s conclusions a bit lacking...

That is the exact opposite of what the testing shows. Poly works better except when solar conditions are perfect. Since he did not test in ideal conditions, we have no way of knowing if mono would truly outperform poly.

The first "hints" of this were published on rvnet a lot of years ago when someone by chance bought two panels, one poly and one mono. The poly out performed in real life conditions. And yes the poly are always larger.

Red, they all rated 100 watts. Poly is supposed to be more efficient. Mono needs three more cells to “make” 100 watts. Test didn’t show more efficiency.

I do not understand comparing 36 cell panels to 33 cell panels.

I went mono since three fit across the front. Would have gone poly if they had not. Due to heat I never considered flexible panels

“ The mono is better for RV use. Mono should be more efficient. In reality there is minimal difference, but I spring a few bucks extra always for the mono.”

Agreed, but this additional efficiency manifest itself via a smaller footprint - regardless of which substrate, 100w is still 100w, thus I find the panel presenter’s conclusions a bit lacking...

In terms of plywood construction analogy, mono is plywood and poly is OSB.

The poly is made of chips of silicone, while the mono is a whole piece. The mono is better for RV use. Mono should be more efficient. In reality there is minimal difference, but I spring a few bucks extra always for the mono.

You see in the video there are a bunch of squares in the panel, then there are about 4 faint lines running up and down within each square. The more lines the better. Some cheap panels will have only 3 and higher quality will have 4 or 5. These lines are conducting the power from the silicone and more is better in this case.
(not so much the number, but the distance between as the square sizes might not all be uniform).

Panels need air flow under them or they overheat. Too many people use the inferior flexible panels and mount them directly to a surface where there is no air flow; you must have air flow to cool the panels, they will get VERY hot otherwise and degrade.
I once had to use the flexible for an application, but mounted them on corrugated plastic mounted on strips of corrugated plastic strips so there was 100% airflow under them. This kept them cool.
Flexible panels will have a much shorter lifespan than glass, so choose glass every time if you can.
Flexible panels are meant to flex once! Put them in place and do not ever bend them again. Bending will eventually break or crack the conductors.