This Caravan Now Charges Faster Than Mains Power

In this episode we take a look at a full electrical upgrade on a Supreme Spirit caravan, transforming a basic AGM setup into a high-capacity, fully off-grid system. This van originally came in with a simple battery setup and limited solar, making it restrictive for extended off-grid use. The goal of this build was to significantly increase capacity, improve system performance, and utilise otherwise unused space inside the van for a clean and functional electrical install. We’ve completely reworked the system layout, relocated the battery setup, and integrated a full Victron system to deliver reliable off-grid power while maintaining compliance and usability. System Overview Victron MultiPlus 3KVA inverter/charger Victron Cerbo GX monitoring system 3 x 350Ah lithium batteries (1050Ah total) 4 x solar controllers (multi-circuit setup) Approx. 1600W roof-mounted solar DC-DC charger from tow vehicle (tuned for alternator limits) Upgraded Anderson plug and cabling Battery system mounted externally in custom enclosures Internal electrical cabinet with ventilation and temp-controlled fans Tank level monitoring system Fully protected DC and AC circuits with compliant protection One of the key improvements in this build is the overall system capacity and charging performance. With over 1000Ah of lithium and a large multi-circuit solar array, this setup is capable of delivering substantial charge current, allowing the system to recover quickly even in less-than-ideal conditions. The battery system has been relocated and mounted externally on the chassis, improving weight distribution and freeing up internal space for a dedicated electrical cabinet. This cabinet houses the inverter, protection systems and control equipment, all neatly installed with proper ventilation and temperature management. We’ve also configured the DC-DC charging system to suit the vehicle’s alternator limitations, ensuring reliable charging without risking damage to the tow vehicle. This allows the system to safely supplement solar input while travelling. The solar system has been significantly expanded and split across multiple circuits, maximising efficiency and allowing for additional inputs such as portable panels or integration with an external off-grid setup. Overall, this build focuses on delivering a high-capacity, well-balanced and reliable off-grid system, designed for extended travel without relying on powered sites. If you’ve got any questions about the setup or need help with your own caravan or off-grid build, feel free to leave a comment or get in touch at [email protected]