Hello ,

i just found this amazing forum and this already helped alot with my project .

i am planning an off grid PV system for a small colthing factory and until now i calculated the nombres of panels needed 208 ,375 Wp so the total is 78 KWp ,

i am trying now to find the right Inverters so i used the "SMA sunny design web" and saw that one of the parameters used in the portal to check the system compatibility is the ratio between the Nominal AC power of the PV inverter (Sunny Tripower) and the battery inverter (Sunny Island), which should be lower than 2. What is the reasoning behind of this?

my many questions are and i am sorry for that :

is the sunny Island a charge controller?

how to calculate the sizing of sunny island ?

and how to determine the voltage of the batteries ? because i have a big system like what i have ,i think with 48 V batteries i am gonna need a **** ton of batteries and wiring which is bad,and i could not find a batteries with bigger voltage ..

i just found this amazing forum and this already helped alot with my project .

i am planning an off grid PV system for a small colthing factory and until now i calculated the nombres of panels needed 208 ,375 Wp so the total is 78 KWp ,

i am trying now to find the right Inverters so i used the "SMA sunny design web" and saw that one of the parameters used in the portal to check the system compatibility is the ratio between the Nominal AC power of the PV inverter (Sunny Tripower) and the battery inverter (Sunny Island), which should be lower than 2. What is the reasoning behind of this?

my many questions are and i am sorry for that :

is the sunny Island a charge controller?

how to calculate the sizing of sunny island ?

and how to determine the voltage of the batteries ? because i have a big system like what i have ,i think with 48 V batteries i am gonna need a **** ton of batteries and wiring which is bad,and i could not find a batteries with bigger voltage ..

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