# VanPowerCalc

> Free electrical sizing calculator for campervans, vans, and motorhomes. Calculate batteries, solar panels, inverters, wire gauges, and DC-DC chargers for 12V and 24V off-grid systems. Available in English, French, German, Spanish, and Italian. No account required.

VanPowerCalc helps van lifers and campervan builders size their 12V/24V electrical systems. Enter your appliances and get exact battery capacity (Ah), solar panel wattage (W), wire cross-section (mm²), inverter sizing, and DC-DC charger recommendations. All calculations follow standard electrical engineering formulas (Ohm's law, voltage drop, Peukert effect for lead-acid).

## Core Calculators

- [Electrical Balance Calculator](https://vanpowercalc.com/en): Main tool — enter appliances, get battery capacity, solar wattage, and wire sizes. Supports LiFePO4, AGM, and gel batteries. Generates a PDF shopping list.
- [Wire Size Calculator](https://vanpowercalc.com/en/wire-size-calculator): Calculate cable cross-section (mm² or AWG) for 12V/24V DC circuits. Factors in length, current, and acceptable voltage drop to prevent fires and energy loss.
- [DC-DC Charger Calculator](https://vanpowercalc.com/en/dc-dc-charger-calculator): Size your alternator-to-battery charger (B2B) for LiFePO4 systems based on driving time, battery capacity, and alternator output.

## Technical Guides

- [Battery Guide](https://vanpowercalc.com/en/guides/batteries): LiFePO4 vs AGM vs Gel — choosing the right battery chemistry for your van build. Covers depth of discharge, cycle life, temperature behavior, and parallel wiring.
- [Solar Panel Guide](https://vanpowercalc.com/en/guides/solar): Sizing solar panels for campervan installations with real-world irradiance data. Mono vs poly, MPPT vs PWM controllers, shade impact.
- [Inverter Guide](https://vanpowercalc.com/en/guides/inverter): Pure sine wave vs modified sine wave inverter selection. Continuous vs peak wattage, grounding, and installation best practices.
- [Wiring & Fuses Guide](https://vanpowercalc.com/en/guides/wiring-fuses): Cable sizing, fuse protection, and safe wiring practices for 12V systems. Bus bars, terminal blocks, and circuit breaker placement.
- [Cable Section Guide](https://vanpowercalc.com/en/guides/cable-section-inverter): Calculating wire cross-section between inverter and battery bank. Maximum length tables for common setups.

## Specialized Tool Pages (Programmatic SEO)

VanPowerCalc provides 175+ localized landing pages covering specific van electrical topics:
- Battery sizing for specific van models and use cases
- Solar panel calculations for camping-cars, fourgons, motorhomes
- Wire gauge calculations for specific 12V circuits
- Comparisons between battery chemistries (LiFePO4 vs AGM)
- Alternator charging and shore power hookup guides

Each page includes an interactive calculator, FAQ section, expert tips, comparison tables, and affiliate product recommendations.

Browse all tools: https://vanpowercalc.com/en/tools

## Key Technical Facts

- Battery capacity formula: Ah = (daily Wh consumption × days of autonomy) / (voltage × depth of discharge)
- Solar panel sizing: Wp = daily Wh / (peak sun hours × system efficiency × controller efficiency)
- Wire cross-section: mm² = (2 × length × current) / (conductivity × max voltage drop)
- Voltage drop threshold: max 3% for lighting, 5% for other loads (12V DC systems)
- LiFePO4 usable capacity: 80-90% DoD vs AGM: 50% DoD
- MPPT controller efficiency: ~95-98% vs PWM: ~75-80%

## Languages & Localization

All content is available in 5 languages with localized URLs:
- French (fr) — default: https://vanpowercalc.com/fr
- English (en): https://vanpowercalc.com/en
- German (de): https://vanpowercalc.com/de
- Spanish (es): https://vanpowercalc.com/es
- Italian (it): https://vanpowercalc.com/it

## About

Built by Leo, a developer and full-time vanlifer. Free, no tracking cookies, no account required for basic use.
- Website: https://vanpowercalc.com
- About: https://vanpowercalc.com/en/about
- Contact: leo@vanpowercalc.com
- Full documentation: https://vanpowercalc.com/llms-full.txt