Free electrical planning guide · AU + US

Plan your van electrical system before you buy parts.

Use this page to make the big decisions first: battery storage, solar, alternator charging, inverter and shore power. The full technical guide is available after signup once you are ready for diagrams, parts and installation detail.

12V planning Solar + DC-DC charging Real-build lessons

Get the electrical guide

Drop your email below and I’ll send you access to the full technical guide library.

  • batteries, solar, MPPT and DC-DC charger setup
  • cable sizing and fuse sizing reference
  • shore power, inverter and charger layout notes
  • plain-English commissioning checks before first use

You’ll get access to the guide library after signup, including the electrical and plumbing technical guides.

A good van electrical system starts with your actual use, not a shopping list. Work out what you need to run, how long you stay off-grid, and how you will recharge before choosing batteries, solar panels or cable sizes.

How a simple van electrical system fits together

Your house battery stores energy. Solar panels charge it through an MPPT controller, and a DC-DC charger can recharge it while you drive. Your 12V loads run through properly protected circuits; an inverter is only needed for appliances that genuinely require mains-style power.

Garage electrical installation in Jared's van build, showing inverter, battery and wiring

Four decisions to make first

These choices determine the rest of the system. They are planning questions, not a substitute for a design specific to your van and equipment.

1. Your daily power use

List what you will actually run: fridge, lights, fans, laptops, pumps and any high-draw appliances. This gives you a sensible starting point for battery and solar planning.

Use the battery sizing guide →

2. How you recharge

Solar helps when parked; a DC-DC charger helps while driving. Most off-grid builds use both, but the balance depends on your travel pattern and roof space.

Read the DC-DC charger guide →

3. Whether you need an inverter

Do not add large mains-powered loads by default. Decide what must run from an inverter, then allow for its demand in the wider battery and charging plan.

Try the solar calculator →

4. Mains and shore power

Keep the 12V planning separate from mains work. Shore-power connections, inverter outputs and mains outlets need the right design and professional inspection.

Start with the free build guide →
Important: this page helps you plan the system. It is not a wiring instruction or electrical certification. Have 240V/mains work inspected by a licensed electrician before energising it.

What I learned from rebuilding mine

I rebuilt and upgraded my van electrical setup over several years. The expensive mistakes came from trying to decide the system as I installed it. Planning the loads, charging sources, access for servicing and protection first makes the build far easier to troubleshoot later.

Free resources for the planning stage

Solar sizing

Work through roof space, daily use and realistic charging expectations before buying panels.

Read solar sizing →

What’s inside

  • the core 12V system layout from battery to fuse block
  • solar input, MPPT sizing and DC-DC charging
  • inverter, shore power and charger decision points
  • cable sizing, voltage drop and fusing basics
  • final checks before you power the system up

Who it’s for

This guide is for DIY van builders who want a real-world electrical plan, not a vague list of components.

  • builders planning an off-grid van electrical system
  • people choosing between AGM and lithium setups
  • AU and US readers who need parts references
  • anyone wanting fewer mistakes before crimping and wiring

Still in the planning stage?

The free main campervan build guide is still open online and gives you the full build overview before you dive into the technical details.

Read the free starter guide