I have a couple of quotes here.
What i am looking at is a sungrow 3 string 5kw inverter.
I do have a question re minimum panels for a string. One company tells me that 3X 440W panels is fine, the other tells me that its not enough. Green Solar in Brisbane is well reviewed and they tell me no, and sure Solar in Brisbane tell me its ok, this has caused me some confusion. Attached are some layouts, calculations and quotes.
I was hoping to get as many panels on east and west as possible while staying within the rules, i am happy to have some panels portrait and others landscape.
What do you Pros think?
The quotes are all very reasonable and use good panels and inverters (for the price).
The string voltage is critical to the system’s performance, and three panels are generally not enough.
I just calculated the string voltage using the string voltage calculator, and the min voltage (on a hot day) is around 85V, which technically could work but would not perform well compared to a longer string. Also, the Sungrow inverter cannot accept parallel strings using the Canadian panels, so two groups of three strings isn’t technically possible.
Thank you for clarifying.
My hope was to maximise the peak energy times, morning and afternoon, east and west. It seems that i may have to get micros for east and west and a single string for the north, or just for for a north south orientation.
If i was to put a 4th panel on the other west facing roof with Tigo optimisers on these 4 panels and just 7 panels north facing then go for a 4Kw inverter would this work or would i be better off sticking with a 5Kw inverter and a north south orientation?
Thanks in Advance
More panels are always better, especially on overcast (cloudy) days, as the solar orientation doesn’t matter. The dispersed light is almost equal on all panels in any orientation.
In summer, the south-facing panels will generate very well; in winter, they won’t work as well, but overall it will generate more annually.