Libre Solar

The Libre Solar designs are for implementing renewable energy systems so electrical power can be generated distributed, locally and regeneratively. It contributes significantly to the renewable energy transition with a buttom-up approach from the people learning and building their own energy systems. The current development takes place in git-based environments (mainly Github). With that the design documentation including CAD files, bill of materials and assembly guidelines as well as user manuals can be shared and accessed openly so everyone can modify and contribute.

The Libre Solar Project started with the primary ideas of a smart, distributed and hackable DC energy system which emerged from discussions during the POC21 innovation camp near Paris in September, 2015. We were planning to combine different renewable energy sources of the single projects (solar generator, $30 wind turbine, bicycle generator) into a system which would be able to provide energy for small household consumers, green houses, electric bikes, etc.. The only problem: There were no open-source and hackable power electronics devices available which would fulfill our needs.

Since then, we are trying to close this gap and develop flexible solar charge controllers, mobile solar systems and battery management systems as open-source hardware projects. With our Open Educational Resources (OER) we want to share the knowledge in the field of small-scaled renewable energy systems.

The Libre Solar project is closely linked to the Fablab Fabulous St. Pauli in Hamburg, Germany, where we can use equipment like laser cutter, reflow oven and a semi-automatic pick and place machine to build prototypes.

LIBRE SOLAR BOX demonstrates as a small-scaled energy system how regenerative energy supply with photovoltaic and battery storage works. The understanding can be transferred to larger systems and thus contribute to the renewable energy transition. Especially because the hardware and software are open-source, anyone can study, develop, improve, modify, build and repair the system.

We have designed and prototyped two versions so far in addition to a battery management system (BMS):

– 360 Wh with 12 V battery voltage and 10 A maximum current (funded by INTERFACER project). Find the repository here.

– 920 Wh with 12 V battery voltage and 20 / 50 A maximum charge / discharge current (funded by Hamburg Open Online University). Find the repository here.

-LIBRE SOLAR BMS C1. A BMS board with up to 16 battery cells and a maximum current of 100 A, capable of up to 4,8 kW power generation! The development of this BMS was funded by the EnAccess foundation. Repositories can be found through our website and GitHub.