Campervan Electrical Budget Planner

Rough-in the true cost of your 12 V system: batteries, solar, inverter, chargers and wiring. Get low–mid–high ranges in minutes.

I don’t know my daily Wh/day — what should I enter?

List your devices, hours and watt draw (or use a DC Load & Daily Energy Budget tool) and add a 10–20% buffer. You can start with 800–1,200 Wh/day for light use and adjust after a week of real measurements.

AGM vs LiFePO₄ — which should I choose?

LiFePO₄ costs more but is lighter with higher usable capacity (~80% DoD vs ~50% for AGM) and better cycle life. AGM can be fine for budget builds or small banks. If weight and space matter, lithium usually wins.

Do I really need a DC-DC charger?

On most modern vans, yes. Smart alternators won’t reliably charge a house bank without a DC-DC unit. It also protects both alternator and batteries with proper limits.

How accurate is the suggested solar size?

It’s a planning ballpark based on your Wh/day and a usage profile. Real yield depends on latitude, season, shading and tilt. Treat it as a starting point, then check your **roof area** and local sun hours.

What about installation hardware and small parts?

The planner includes a **wiring/fuses/misc** allowance as a percentage of hardware. You’ll still need to price mounting, glands, lugs, heat-shrink and tools when you firm up your parts list.