Libre Solar Box

This Open Hardware project is about the development of a solar box. We want to provide a compact, mobile and modular electric power generator. An alternative to the diesel generator. The power specifications are chosen to supply a mini house, a boat, a caravan, or any other off-grid devices like a music station on an open-air.

The aim is that everybody is possible to rebuild the solar box at home or at his/her favourite fablab.

Documentation still under developmentā€¦

You find our development process of the solar box on following GitHub repository. Feel free to fork and contribute.

Some impressionsā€¦

Overview of the Libre Solar Box layout.


CAD model of the solarbox V0.2 designed in FreeCAD.


Finshed assembly of the solarbox V0.2 with wood housing and acrylic glas on one site.


  • Maximal Voltage Input = 55 V
  • Maximal Power Input = 300 Wp
  • Capacity of Batteries = 920 Wh
  • DC Output Voltage = 12 V and 5 V (USB-power)
  • Maximal Power Output = 600 W


  • electric: Libre Solar (MPPT+BMS), Inverter (Victron), ESP/Rasbperry, Fuse
  • Batteries: LiFePO4 (Calb), 72Ah, 3,2V, 230,5Wh - 4x -> 12,8V, 920Wh
  • Housing/Frame: UniProKit, with corner elements for blending; wood plates for mounting electric parts and batteries
  • Interface: Solarinput (MC4), DC-output (car plug), AC-output (schuko, integrated in inverter), main switch


  • Open Energy Monitor via CAN to ESP (Server ext.)/Rasbperry (Server int.)
  • browser based visualization -> access via LAN/WLAN