What would the expected actual real world PV output be for 21 330W panels.

According to the given rating the maximum theoretical output is 6930W.

What should we though expect the real output to be In Pretoria at peak with no clouds?

 

direction and angle of panels?

inverter used?

cable specification?

distance of cable?

On a 20 panels setup I am avg around 44kw/day

Not specifically referring to any make or the total kwh per day or any other setup losses.

Just want to know what would the expected maximum Wattage output be if nothing is limiting solar.

Is the 330W rating given as the expected maximum output?

21 panels  = 330 X 21 = 6930W

Only cabling / inverter / setup would actually be responsible for further loss?

 

ps:

Re: "On a 20 panels setup I am avg around 44kw/day"

I didn't want to complicate the calculation further with a kwh value.... # hours sun per day is variable

If you have 5 hours per day of maximum solar eficiciency: W = 44/5 = 8800W max output -> which is obviously far higher than 330 X 20 = 6600

... so obviously you get more than 5 hours sun per day (44/8 = 5500W)  and output is lower before and after peak.

... whatever the hours of sun it looks like your maximum Wattage output is very similar to the calculated max of 330 X 20 = 6600 ?

 

I believe based on our responses that you looking at a spot number right?

Peak I have seen on the graph was 7.2kwp on a clear day.

But unfortunately the variables responsible for your answer impact the production so I am out of responses.

Perhaps the more experienced guys  than me can guide.

Sam, discarding all the influences, You can typically expect a Maximum value of around 8316W, but on normal clear sunny day it should produce around 5775W during peak time.

PS:  most of my installs have an avg production per day above 90% of "simulation"

Thanks Fazil / Riaan

Looks like we have both higher and lower than rating value real world results.

Being conservative it appears that i should not expect the peak "spot" output to be less than 90% of the PV panel rating.

Anything higher is bonus.

6930 X * 90% = ~ 6200W

 

 

Sam your peak output is also highly dependent on the time of year vs. your array tilt.

Around this time of year my panels produce >95% of their rated power (after cabling/inverter losses) at solar noon (around 12:20), since my roof is tilted at 5 degrees North, which happens to be the optimal tilt this time of year.

As the year rolls on I'll peak less and less. 

As alluded to above you should be more concerned with KWh produced daily since spot output varies during the day.

There are cool apps out there to play around with like PV Solar Forecast and SunCalc.org.

Hi Jannie

Total production is a matter of a lot of factors to give kWh per day/month/year. The question is not about total production.

The point was to remove the variable factors and determine real world results for the maximum spot power output expected vs the PV panel rated value - the PV panel rating value is not kWh.

Graph below is for an installed system with 21 X 330W panels on a very sunny day. Max power was just over 4kW.