I am building a home in a sunny, dry part of Hawaii where electricity is very expensive. I will have significant electrical loads including a 6 ton central AC system (4 zones), 10x60' pool with pool pump and HPHW pool heater, two 80 gal HPHW tanks, stove, oven, refrigerator, washer, dryer, dishwasher, and 2 EVs. We originally designed the home to have a large south (S) facing roof pitch but my HOA made me chop up my roof to make it more "interesting", which markedly reduced my S facing roof area. Four of my neighbors had their solar systems professionally installed on their new homes (without any consumption records) with more than 50 panels each but they don't have as many loads as I will have. Two of them were lucky enough to have NEMs but the other 2 are now pricing batteries. I hope to install 2 PW2 or 3 LG Chem batteries (RESU10) to store energy for evenings and night use. I have already purchased two new inverters, SE10000H-US and SE7600H-US (at half price). I plan to design the solar layout for maximum use of both inverters but may not install that many panels. I think that it will be cheaper to downsize than to upsize my installation.
My roof is completed but doesn't show up yet on google maps, so I can't use the Solaredge solar design tool.
Based on my roof dimensions and pitch, my architect calculates that I can only fit 29 panels (Panasonic 325w) on my S facing pitches, see attached layout. At the maximum oversize rate of 1.55 for SE HD wave inverters, I theoretically could connect 47 325w panels to my SE10000H-US inverter and 36 325w panels to my SE7600H-US inverter. I need to distribute these panels on my S, W and E facing pitches to minimize clipping. I think that I would minimize clipping by connecting ~57% (10/1 7.6) of panels on each pitch to my SE10000H-US inverter and 43% (7.6/17.6) of panels on each pitch to my SE7600H-US inverter but that get complicated when building strings. Each pitch will have a different time of peak production, which helps to avoid clipping.
Do I need to try to distribute S, W and E facing panels somewhat evenly between the 2 strings of each inverter or should I be more concerned with not having a string with less than a given number of E or W facing panels. I recall reading that with E and W facing panels that you should avoid having less than a certain number in a string for low irradiation times.
Also, I read in one place that the min, max # panels on a string was 8, 25. Is that correct or is the maximum number of panels in a string calculated with a formula?
Thanks in advance for any assistance.
190624 MKW Solar 29S 32W 23E.jpg
My roof is completed but doesn't show up yet on google maps, so I can't use the Solaredge solar design tool.
Based on my roof dimensions and pitch, my architect calculates that I can only fit 29 panels (Panasonic 325w) on my S facing pitches, see attached layout. At the maximum oversize rate of 1.55 for SE HD wave inverters, I theoretically could connect 47 325w panels to my SE10000H-US inverter and 36 325w panels to my SE7600H-US inverter. I need to distribute these panels on my S, W and E facing pitches to minimize clipping. I think that I would minimize clipping by connecting ~57% (10/1 7.6) of panels on each pitch to my SE10000H-US inverter and 43% (7.6/17.6) of panels on each pitch to my SE7600H-US inverter but that get complicated when building strings. Each pitch will have a different time of peak production, which helps to avoid clipping.
Do I need to try to distribute S, W and E facing panels somewhat evenly between the 2 strings of each inverter or should I be more concerned with not having a string with less than a given number of E or W facing panels. I recall reading that with E and W facing panels that you should avoid having less than a certain number in a string for low irradiation times.
Also, I read in one place that the min, max # panels on a string was 8, 25. Is that correct or is the maximum number of panels in a string calculated with a formula?
Thanks in advance for any assistance.
190624 MKW Solar 29S 32W 23E.jpg
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