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Van power calculator

Work out how much battery, solar and inverter you need for your campervan, based on how you actually use it. Select your appliances and rough daily usage, and get recommended sizes.

Your daily usage

How this works. We total your appliance watt-hours, add ~12% for inverter losses, then size a LiFePO4 battery to cover roughly two days on 12V with 90% usable depth, solar from ~4.5 effective sun-hours per day, and an inverter sized to your largest single appliance plus headroom. These are planning estimates to help you choose gear, not engineering specifications. Always confirm with a qualified installer before buying or wiring.

See the full sizing guide for the method behind these numbers, or how much solar for the solar side.