Van & RV Power System Simulator

Free interactive planning tool

Plan Your Van or RV Power System in Minutes

Model a typical 24-hour day, compare solar conditions, and see how appliance loads, battery storage, alternator charging and shore power work together.

✓ 24-hour energy model ✓ Sunny, cloudy and no-solar comparison ✓ AC and DC loads handled separately
Start with an example:
1 Build your scenario

Enter Your System

Battery and solar

Inverter and charging

Daily appliances

Use measured watts when possible
2 Review the estimate

Your 24-Hour Energy Picture

Enter your system and run the simulation.
Daily consumption
Modeled charging
Daily balance
Lowest charge
Lowest modeled battery charge
Battery chargeSolar production

Planning checks

    Planning estimate only. Actual performance changes with weather, temperature, shading, wiring losses, charger limits, battery settings and appliance behavior. Verify the final system against current manufacturer documentation and qualified guidance. This tool does not select wire or fuse sizes.

    Better inputs, better estimate

    How to Get a Useful Result

    • Use measured appliance wattage and realistic daily run time.
    • Choose DC for loads powered directly by the battery and AC for loads powered through the inverter.
    • Enter motor or compressor surge only as a documented planning value.
    • Run sunny, cloudy and no-solar scenarios before relying on one favorable day.
    Know the limits

    What This Model Can—and Cannot—Do

    The simulator estimates daily energy flow and compares charging scenarios. It does not approve a battery, inverter, wire, fuse, solar controller or installation.

    Its LiFePO4 and lead-acid reserve settings are transparent planning assumptions, not universal manufacturer limits. Temperature, battery-management behavior and equipment settings still matter.

    Frequently asked questions

    Power Simulator Questions

    Does this recommend an exact battery size?

    No. Battery choice must also account for maximum current, temperature, reserve requirements, charging limits, cycle life, installation and the exact battery manual.

    Why are AC and DC appliances calculated differently?

    A DC appliance is supplied directly by the DC system. An AC appliance also passes through the inverter, so the model includes the entered inverter-efficiency loss and checks the inverter’s running and surge ratings.

    Can it choose fuse and wire sizes?

    No. Fuse and conductor selection depends on ampacity, insulation, installation method, terminals, temperature, circuit length, equipment requirements and applicable standards.

    Why can a balanced day still show a low battery point?

    Total charging may exceed consumption while energy arrives at the wrong time. Loads used before meaningful solar production can lower the battery first, with charging recovering it later.

    Are the results guaranteed?

    No. Results are educational estimates based on user inputs and simplified assumptions. They are not an electrical design, installation instruction, certification or substitute for professional review.