5kW off-grid photovoltaic system -

DoItYourself photovoltaic 5kW off-grid system with components, references, specifications, materials, cost breakdown by each component and more.

Cost

The total was around ~15.000 RON (~3.000 USD) + DIY study and work. Here is the breakdown by main components: battery, inverter and photovoltaic.

        14495.74 RON  Expenses
         3287.00 RON    Battery
          692.00 RON      BMS
          290.00 RON      Box
           90.00 RON      Fuse
         2000.00 RON      Li-Ion cells
          215.00 RON      Materials
         4050.00 RON    Inverter
         3800.00 RON      Growatt
          250.00 RON      Materials
         6858.74 RON    Photovoltaic
          129.30 RON      Accessories
           58.00 RON      Box
          325.89 RON      Cable
          137.00 RON      Discharger
           81.97 RON      Fuse
         5284.00 RON      Panels
           50.00 RON      Transportation
          350.00 RON      Wood
          300.00 RON    Workmanship
--------------------
        14495.74 RON

Note: exchange rate 1 USD = ~5 RON (give or take, keep it simple)

Battery

Pack

Bak 18650 3.6V 2900mAh
18650 Li-Ion battery: 18mm circumference, 65mm long, 0 type cylindrical
3.6V nominal voltage, 4.2V max voltage and 2900mAh nominal capacity
battery pack is 14S28P (14 serie, 28 parallel); total 14*28= 392 batteries
4.2V * 14S = 58.8V max voltage
2.9Ah * 28P = 81.2Ah max capacity

Battery Management System (BMS)

JK-B1A24S15P Active Balancer BMS
Bluetooth + mobile iOS/Android app
active balance current: 1A
2 heat sensors

Inverter

Growatt SPF 5000 ES
3in1 inverter with PV and charge controllers
WiFi + mobile app
nominal power: 5kW
max PV power: 6kW
max PV charge current: 100A
max PV input voltage: 450V

Photovoltaic (PV)

Panels

JA Solar 455W
Voltage at maximum power (VMPP): 41.82V
Intensity at maximum power (IMPP): 10.88A
Peak Power (PMAX): 455W
total installed PV power: 455W * 6 panels = 2.7kW

Flatroof system

DIY support system inspired by CompactFlat S15
hybrid solution (metal + wood) support with 3rows x 2columns = 6 panels
inclination angle: ~50°
orientation: South
internal shading: ~15° on Dec 21st (winter solstice) at 10am, Sun azimuth 150°

References

diy photovoltaic battery inverter off-grid solar