Step by step design of off grid PV systems - PV SIZING

Example: Design an AC decentralized PV power system to supply a load that needs 3920 Wh/day. The efficiency of the inverter, regulator and battery are 97%, 96%, 85% and considering the battery DOD is 75%. The design safety factor is 1.15 and the Peak Sun Hours for the location is 5.4 hours.

PV Sizing




For this PV power rating, the DC bus voltage is 24 V DC.

Assume that the PV module that will be used has a Vmp = 17.2 V and Imp = 2.9 A.

So, TWO PV modules should be connected in series to be able to charge the battery system at a DC bus voltage of 24 V.

The total current supplied by this PV system = Ppv / (2*Vmp) = 897 / 34.4 = 26 A

So, the number of parallel PV strings = Total PV current / current per each string = 26/2.9 = 8.96 >>>>>> = 9 STRINGS