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Since early 2026, energy grids across Europe have been under serious strain. Fuel shortages, spiking electricity prices, rolling blackouts in some regions. Me? I couldn't care less. Not because I'm heartless — I just built my van's electrical system to depend on nobody. And I'll show you exactly how to do the same.
My current setup: 400W of solar panels and a 200Ah LiFePO4 battery. In summer across southern Europe, that generates 1,600–1,900Wh per day. Plenty for the fridge, laptop, lights, phone charging, and even a small inverter for morning coffee. Total investment: $1,500–3,000 — roughly what a US household spends on electricity in a single year at 2026 rates.
⚡ Expert tip
Measure your actual consumption for 3 days before sizing anything. Most people overestimate their needs by 30%. A $15 watt meter on each appliance will save you from oversizing — and overpaying for — your entire system.
Example calculation for your setup
Results based on a typical use case
| Appliance | Power | Usage/day | Wh/day |
|---|---|---|---|
| Compression fridge | 45W | 24h | 1080 |
| LED lighting | 20W | 4h | 80 |
| Water pump | 30W | 0.5h | 15 |
| Phone charging | 15W | 2h | 30 |
| Daily consumption | 1205 Wh | ||
Recommended LiFePO4 battery
126 Ah
(80% depth of discharge)
Recommended AGM battery
201 Ah
(50% depth of discharge)
Adjust these values with the calculator below
VANPOWERCALC PROYOUR ENERGY PROFILE
YOUR ENERGY PROFILE.
This document contains the sizing of your future electrical installation, calculated based on your appliances.
Minimum Daily Consumption
0 WH / DAY
Inventory:
SYSTEM SIZINGPage 2
Battery
To guarantee 0WH without damaging your bank (80% max discharge):
0 AH
LiFePO4 12V
Solar
Minimum power required to recharge your consumption:
0 W
via MPPT
220V AC
Maximum power (with 25% safety margin).
0 W
No Need
Safety & CablingPage 3
12V Cable Sizing Guide
Use this professional reference table to select the correct gauge (mm²) for your cables. For 12V in a van, the maximum tolerated voltage drop is 3%. Always use multi-stranded flexible automotive wire.
| Current (A) | Round trip < 2m | Round trip 4m | Round trip 6m |
|---|---|---|---|
| 5A (LEDs, USB) | 1.5 mm² | 2.5 mm² | 4 mm² |
| 10A (Fridge, Pump) | 2.5 mm² | 4 mm² | 6 mm² |
| 20A (Heater) | 4 mm² | 10 mm² | 10 mm² |
| 50A (DC/DC Booster) | 10 mm² | 16 mm² | 25 mm² |
| 100A (Inverter) | 25 mm² | 35 mm² | 50 mm² |
Fuse Sizing
The fuse protects the wire, not the appliance. Always place it as close to the power source as possible (battery or busbar).
- Wire 1.5 mm² → Max fuse 10A
- Wire 2.5 mm² → Max fuse 20A
- Wire 4 mm² → Max fuse 30A
- Wire 6 mm² → Max fuse 40A
- Wire 10 mm² → Max fuse 60A
SCHÉMA ÉLECTRIQUE
PANNEAUX SOLAIRES
0W
REGULATEUR MPPT
BATTERIE AUXILIAIRE
0 Ah
Lithium LiFePO4
FUSIBLE
FUSIBLE
BOÎTE À FUSIBLES 12V
Pompe, Leds, Frigo...
CONVERTISSEUR 220V
NON REQUI
PRO GEARPage 4
SHOPPING LIST
Where to find this equipment? Here is the community-approved selection.
12V 6-way Fuse Box
Mandatory protection
Digital Multimeter
Test your connections
Heavy Duty Crimping Tool
For perfect lugs
Heat Shrink Tubing
Insulation and safety
GENERATED BY VANPOWERCALC PRO - UNLIMITED.
About this tool
The comparison is brutal. An average US household pays around $2,000/year on electricity in 2026 with crisis pricing. A vanlifer with 400W solar and a 200Ah LiFePO4 pays... $0. The upfront cost sits between $1,000 and $5,000 depending on the setup, but solar has no monthly bill, no rate hikes, no surprise fees.\n\nI ran the numbers over 5 years. With a $2,500 setup, amortized cost comes to about $500/year, then it's free. The LiFePO4 battery lasts 3,000 cycles minimum — that's 8 to 10 years of daily use. Meanwhile the grid keeps raising prices. Energy independence in a van isn't some hippie dream — it's basic math.
Frequently asked questions
How much does a fully autonomous van electrical system cost?▼
Between $1,000 for a basic setup (200W solar + 100Ah LiFePO4) and $5,000 for a complete system (400W+ solar, 200Ah+ LiFePO4, 2000W inverter, DC-DC charger). Most people land around $2,500 for comfortable autonomy.
Can a van be 100% electrically self-sufficient?▼
In summer, absolutely — 400W of solar handles it easily. Winter in northern latitudes is tougher, expect 50–70% autonomy. A DC-DC charger via the alternator fills the gap when you drive.
How many days of autonomy with a 200Ah LiFePO4 battery?▼
About 1,920Wh usable (200Ah x 12V x 80% DoD). That covers 2–3 days of normal use — fridge, lights, device charging — with zero solar input.
Does solar work in winter for a van?▼
Yes, but output drops 50–70% compared to summer. A 400W array produces around 500–700Wh/day in winter in southern Europe. You either adapt consumption or top up with the DC-DC charger while driving.
Do I need an inverter to be off-grid in a van?▼
Not mandatory, but very useful. A 12V-to-120V (or 230V) inverter lets you run standard appliances — laptop charger, coffee maker, hair dryer. A 1,000–2,000W model covers 90% of needs. Budget $150–400 depending on wattage.
Recommended gear
Editor's PickLiFePO4 Battery 100Ah100% usable capacity, 3000+ cycles, built-in BMS.View on Amazon →Editor's PickComplete 200W Solar KitPanel + MPPT controller + cables, ready to install.View on Amazon →Pure Sine Wave Inverter 1000WPure sine wave, sensitive devices compatible, 12V→110V/230V.View on Amazon →Digital MultimeterMeasures voltage, current, resistance — essential for 12V wiring.View on Amazon →