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.

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current system layout, V0.1

The current Libre Solar Box system contains following specs and modules:

specs:

• V_input_max = 55V
• P_input_max = 300Wp
• C_batteries = 920 Wh
• V_dc_out = 12V
• P_dc_out = 300W, theoretically 600W -> not tested
• (V_ac_out = 230V, 50Hz) optional
• (P_ac_out = 250W) optional -> depend on inverter

modules:

• 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

visualization:

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