This is the place to ask questions, share your setup, and get help with every part of your van’s electrical system – from batteries and wiring to solar and inverters.
Whether you're building your first 12V setup or sizing a full off-grid system, you're in the right place. This thread links to our best resources and tools to help you build safe, reliable, and future-proof electrics.
Helpful guides to get started:
Campervan wiring diagram explained
Helpful calculators to get started:
MPPT Charge Controller Calculator
Battery Charge Time Calculator
Helpful courses & resources to get started:
Electrics Masterclass -Step-by-step video course for designing and installing your full system.
Van Conversion Mastery Course - The full start-to-finish course – includes electrics, plumbing, insulation, and more.
Roaming Home Book - A complete written guide covering every step of the van build process.
Most Common Questions in This Category
What size solar panel do I need?
Use our solar calculator to size your system based on daily energy use.
Which type of battery is best?
Lithium (LiFePO4) for performance and lifespan. AGM if you're on a tighter budget.
How many amp-hours do I need?
Most full-time vanlifers use 200–300Ah. Part-timers often get by with 100Ah.
Do I need a B2B charger if I have solar?
Yes – solar can be inconsistent. B2B keeps your batteries topped up when driving.
Can I charge my leisure battery while driving?
Yes – with a B2B (smart) charger or a split charge relay (if your alternator isn’t smart).
How long will my battery last off-grid?
Depends on usage and charging input. Use the battery charge time calculator.
Should I get a 12V or 230V fridge?
12V fridges are much more efficient – especially for off-grid use.
Do I need an inverter?
Only if you’re running AC appliances like laptops, blenders, or power tools.
How big should my inverter be?
Depends on what you’ll run at the same time. Use the inverter calculator.
What happens if I oversize my inverter?
It’ll use more power at idle. Go only as big as you need.
Can I wire everything myself?
Yes – with the right guidance (like the Masterclass) and safety precautions.
How do I know if my alternator is smart?
If your van is Euro 5+/6 or newer than ~2015, you probably have a smart alternator. Use a B2B charger.
Do I need fuses on every wire?
Yes – fuse every positive wire near the power source. It’s essential for safety.
Can I mix battery types or brands?
No – always match batteries by type, age, capacity, and brand.
Can I put my electrics under the bed?
Yes – as long as it’s well-ventilated, accessible, and protected from moisture.
How can I tell if I’ve got voltage drop?If your lights dim or fridge underperforms, check cable runs and sizing.
Should I run AC or stick with 12V?
Stick with 12V wherever possible – it’s more efficient and simpler to wire.
Can I run an induction hob in a van?Only with a serious system: 2000W+ inverter, 300–400Ah lithium, big solar + B2B.