I wish my solar was more effective - 36 panels and only 40 to 45 kwh per day generated - it was supposed to be generating 60 to 70 per their damn sales pitch.
It is always hard to tell if they (installers) are any good. So many reasons it could be that low. but they mostly boil down to they lied or they installed it wrong.
Also it is the winter you will be much lower numbers now then May,June,July If you are in northern hemisphere.
In NJ we do 9 hours of light in winter and 15 hours of light in summer
average of 12 is not what you use. as those 12 hours come to 5-6 hours of full sunshine So we base NJ numbers at 5 hours a day
They could be using the high number for estimate 6 hours a day.
They could have mismatch inverter
They could have a bad wire job.
this build will be 1000 300 watt panels = 300,000watt or 300kwatt setup but that is a peak number. We divide the 300 by 7 to get 42 kwatt we round to 40kwatt this is very conservative.
The yearly average should be 40kwatt 24/7/365 A lot of installer would bs and say the system will generate 50kwatt 24/7/365 which is really possible but in practice it will be 39-45 24/7/365
we prefer to go low on estimates since customers are happy to do a little more than promised.
