Under performing solar panel.

BBSA

BBSA

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I have a new Canadian 460W mono solar panel, but it only produces about 200W during midday. I'm located in Pretoria, and the panel faces north at a 27-degree tilt. I'm using an 8-meter long, 6mm cable to connect it to the inverter. While I understand I won't get the full 460W output, I expected to see production closer to 300-350W at midday.

Is this an unreasonable expectation for the panel?

Here is the link to the panel: https://www.geewiz.co.za/solar-pane...ower-mono-perc-hiku-with-mc4-evo2-silver.html
 
Did ya check if any cells are cracked? It happens sometimes, but it's rare on a new unit.
 
BBSA said:
I have a new Canadian 460W mono solar panel, but it only produces about 200W during midday. I'm located in Pretoria, and the panel faces north at a 27-degree tilt. I'm using an 8-meter long, 6mm cable to connect it to the inverter. While I understand I won't get the full 460W output, I expected to see production closer to 300-350W at midday.

Is this an unreasonable expectation for the panel?

Here is the link to the panel: https://www.geewiz.co.za/solar-pane...ower-mono-perc-hiku-with-mc4-evo2-silver.html
Click to expand...
What type of a controller is it connected to? And remember that power ramps up with a corresponding power draw, so maybe you are seeing half production because you are only drawing half from it.
 
Did you get the panels from geewiz (or some reliable supplier) , or some suspect backdoor supplier (in which case it could be fake)?
 
You'll only draw the power needed, so if you're only drawing 200w at midday that's what you'll get.
 
You don't have to throw away the inverter, (although I hate that inverter) you can get a stand alone controller and bypass the built-in one.
 
TheChamp said:
You don't have to throw away the inverter, (although I hate that inverter) you can get a stand alone controller and bypass the built-in one.
Click to expand...
That price though, haven't seen an inverter that low for awhile
 
So as I understand it: that panel should be making 460W when there is the 'name plate' radiation landing - - believe this is 1000W/m2. So that depends on 2 things:
1. Weather
2. Angle of panel
(and 3 the power electronics... MPPT vs PWM and there being enough load to use it!)

Looking here https://en.tutiempo.net/solar-radiation/pretoria.html recent weather hasn't got to 1000. No wonder, it IS April!
 
richjdavies said:
So as I understand it: that panel should be making 460W when there is the 'name plate' radiation landing - - believe this is 1000W/m2. So that depends on 2 things:
1. Weather
2. Angle of panel
(and 3 the power electronics... MPPT vs PWM and there being enough load to use it!)

Looking here https://en.tutiempo.net/solar-radiation/pretoria.html recent weather hasn't got to 1000. No wonder, it IS April!
Click to expand...
The 200w is on a cloudless day.
 
TheChamp said:
Ah, there is your answer, PWM charge controller. You need an inverter with an mppt controller to make the most use of the solar.
Click to expand...
Or you need to select the panels better

Now yes an mppt is way better

But lets get back to my original point
Your panels max vmp is at 34.8
34.8x13.24A= 460w

But with a 12v system the panel gets dragged down to battery voltage on a PWM controller

13.24A x 14V = would mean 185w

Now if you selected a 30cell panel with a 18v vmp

Lets say 2x 230watt panels to have the same 460w output now the amps would be 12.77per panel if connected parallel you would get 25.54A at 14v meaning you would get almost 360w from the same 460w array

Panels selection is where lots of the magic happens

ie the closer you get to battery voltage on a PWM the less losses you will have on the rated output

Edit so one 230w panel of the correct voltage would match your current 460w panel
 
BBSA said:
That is disappointing, as I really don't want to spend more money.
Click to expand...
You can use it is and just get less from the panel

You can buy extra panel and parallel more panels for more output just fuse parallel panels

This panel is a nice mppt friendly voltage so in future you can change parallel to series if ever you get a bicer inverter ie even if you switch to 24v later to get faster charging the panel will give more even if you go pwm again though if budget allows mppt is best
 
Wait, are you only running 1 panel?

That more than likely in itself is causing some issues.
 
wingnut771 said:
How so?
Click to expand...

Because he’ll struggle more to get the minimums pushed through the system to get it ticking over properly wouldn’t he?

But I see now it’s all PWM and not MPPT on a small 12V setup so none of it is ideal.
 
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