5kW off-grid photovoltaic system

DoItYourself

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)

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°
comments powered by Disqus