What percentage of the rated wattage is your array producing

ELT

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Feb 12, 2023
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Location
Beaufort NC
Hi
I am a little disappointed in the actual watts produced by my pv array. I have 4kW of panels (1.2 kW facing due south and 2.8 kW facing due east). Due to small yard and new metal shingle roof this arrangement is necessary. I live in the eastern NC hurricane zone and insurance will not cover roof damage if solar is installed on it (separate policy by roofing company covering to cat 4 storms).
The arrays consistently produce about 12kW on sunny days this summer. Based on 7 hours of sun the arrays should produce 28 kW. Voc and current are correct.

I also have a Lion Energy ME in my rv. It has 6 100 watt portable panels and they only produce 300 watts. Again Voc and current are correct.

Is 50% of rated output reasonable?
 
Maybe, maybe not. For one thing it is rare to have a insolation value of 7 hours. You might want to use https://pvwatts.nrel.gov/ to see what you could expect. The other issue of course is your panels optimum angle to the sun.

Most Summer time average will be ~5h. Given that your panels are not optimum. You likely could use 3hours per South and East and have more accurate estimate. Thus 4000w X 3h = 12,000wh
 
Is 50% of rated output reasonable?
Possibly
6 100 watt portable panels and they only produce 300 watts
At summer temps, plus add a little imperfect angle to the sun and overall wiring inefficiencies and that’s probably a 1.5kWh per day. If it’s enough for your needs? Then it’s enough.
have 4kW of panels (1.2 kW facing due south
At what angle?
The arrays consistently produce about 12kW on sunny days this summer
and 2.8 kW facing due east).
Again, angle is relevant - for east facing 2.8kW of panels that are perfectly angled I’d wildhat guess at dependable max of ~5 or perhaps maybe 6kWh/day.
4kW of panels (1.2 kW facing due south
And these with good appropriate angle a wildhat guess is about 6kWh/day
The arrays consistently produce about 12kW on sunny days this summer
which intriguingly and a bit to my surprise is just about what my wildhat number pandering came up with.
I actually went off experience with what I can see with my current 4 small arrays and just went wildhat on it.
Is 50% of rated output reasonable
So, yes. Panels are notably less efficient at higher temperatures.
Plus, the E panels sacrifice a lot at warmer temps and no snow reflectivity. So they only have about 2 hours of reasonable participation.
The S facing panels will do better, about 4-6 hours of great production. But they’re still hot and that curtails output.
 
I also have a Lion Energy ME in my rv. It has 6 100 watt portable panels and they only produce 300 watts. Again Voc and current are correct.

Is 50% of rated output reasonable?

Voc and current (Isc?) are "correct". But actual power harvested is 50% of (STC) rating.
Sounds like Vmp & Imp are not "correct" under conditions where Voc and Isc are "correct".

Do I have that correct?
But you probably mean Voc and Isc of a single panel.
You have arrays of two different sizes facing two different directions.

1) Disconnect one array, check results for a single direction. Peak power and Wh/day.

2) Determine during which hours array has no shade.

3) Provide a schematic for how all panels & charge controller(s) are connected, and specs for both.
 
Hi
I am a little disappointed in the actual watts produced by my pv array. I have 4kW of panels (1.2 kW facing due south and 2.8 kW facing due east). Due to small yard and new metal shingle roof this arrangement is necessary. I live in the eastern NC hurricane zone and insurance will not cover roof damage if solar is installed on it (separate policy by roofing company covering to cat 4 storms).
The arrays consistently produce about 12kW on sunny days this summer. Based on 7 hours of sun the arrays should produce 28 kW. Voc and current are correct.

I also have a Lion Energy ME in my rv. It has 6 100 watt portable panels and they only produce 300 watts. Again Voc and current are correct.

Is 50% of rated output reasonable?
You're exactly where I would expect you to be for a good day. Consider East Coast air quality due to Canadian fires has been poor this year. I was getting way more power in early May than I am now due to smoke, humidity and cloud cover.
 
Heat also impacts production, and we have had a lot of hot days thus far. I am still in general producing what the PVwatts calculator estimated for my array, many times going over it between 3-6kWh. But for your array, not being positioned optimally, sounds about right. My array faces as close to solar south as I can get, is bifacial and 8.9kW face value. 7 hours is way to much to estimate.
 
I have a 15kW array and my best day is 74kWh (May). I'm in NH and 5x is better than I thought I'd get.

Now compare that to June and July where is has rained here at least 20 days each month. I've made about 800kWh each month in what should be 1500-2000kWh months.
 
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