Solar Panel Output - Claimed vs Actual. Add Yours.

biff

Observer
Having recently purchased a new solar panel, I know it is tough (and even daunting) to wade through the internets looking for "good" info on panel output vs rating.
Obviously, there are tons of variables, but thought it might be handy for future solar guys (and gals) to have a thread dedicated to showing comparison of claimed ratings vs actual output.

Manufacture: PowerFilm Solar
Panel: 90w foldable
Highest Output Observed: 86watts
 

calicamper

Expedition Leader
Two Renogy 10 watt hard panels 8 watts each in cool, near perfect summer conditions. Amps matter more. 1-1.3 amps combined is typical for the two.

29 LG 285 watt panels. So far peak in ideal conditions Ive seen 230 watts, but they are fixed and not at an ideal angle or ideal south facing direction. But this week clear days we do 36kwh days easily. The LG panels are rated at 18% efficiency. Most generics like Renogy, power film etc hover in the 12-14% range.
 

workerdrone

Part time fulltimer
Three basically flat mounted Renogy 100w panels wired in parallel in case any shade is encountered on any of them, two Renogy 50w panels stowed in rig and ready to be deployed in a sunny spot should our rig be parked in the shade and the fixed panels insufficient.

After 5 months full timing, efficiency of Renogy 100w panels is excessive :) . 50w panels yet to be deployed. Battery bank lowest overnight voltage has been about 12.50 even after charging laptops, watching lots of TV, running Vitamix and microwave, etc.
 

IdaSHO

IDACAMPER
This is a pretty tough topic to pin down, due to so many variables.

Pretty unfair for any panel unless tested in the same exact conditions.


That said, my 36V Renogy panels look to have less than a 5% loss

I routinely see 96 watts out of each of my 100 watt panels.

With 2 panels, that equates to 14+ amps @ 13.5 V with a cheap ecoworthy controller.
 

4x4junkie

Explorer
The two UL-Solar 85W panels I use are rated 5.15 amps Isc... I measured their Isc yesterday (faced directly at a mid-day sun) and came up with 5.132A (Imp rating is 4.87A, Vmp is 17.5)
Laid flat on the ground I got 3.277A Isc (so about 36% less)

Using a SunSaver MPPT-15 charge controller with the above panels I've seen nearly 12 amps (or ~160 watts) going to the battery.



I also have this little guy to maintain all of the batteries in our motorhome while parked (using it with a LM317T adjustable IC regulator):
http://www.amazon.com/ACOPOWER-Polycrystalline-Photovoltaic-Battery-Charging/dp/B013W38TTK (15W)

Isc rating: 0.91A
Measured Isc: 0.993A
(Imp is 0.85A, Vmp is 17.7)
Laid flat on the ground: 0.64A Isc


I would need to build an adjustable shunt regulator circuit of some sort to accurately measure Vmp & Imp together, which I have not done yet, however I don't have reason to believe these measurements wouldn't similarly live up to their ratings.
 

Forum statistics

Threads
190,005
Messages
2,923,036
Members
233,266
Latest member
Clemtiger84
Top