12V LiFePO4 Batteries — The Heart of Every Van Build Battery selection is the most consequential decision in any van conversion. Undersized banks mean cutting evenings short. LiFePO4 (lithium iron phosphate) batteries have replaced AGM as the standard for serious van builds due to their 80% usable depth of discharge (vs. 50% for AGM), 10-year lifespan, and ability to charge 3× faster. We test 100Ah, 200Ah, and 300Ah banks from Battle Born, Renogy, Ampere Time, and SOK using a calibrated load tester, verifying actual capacity vs. advertised. For a full-time van build with a 12V compressor fridge, we recommend a minimum of 200Ah LiFePO4 with 400W of solar. Van Solar Systems — Sizing and Top Panels Solar panel selection starts with calculating your daily watt-hour consumption — typically 150–350Wh/day for a minimalist setup to 600–1000Wh/day for a van with laptop work, induction cooking, and a large fridge. We test rigid and flexible solar panels for actual wattage output at 25°C, output degradation over 12 months, and panel durability on van roofs. Our picks: Renogy 200W rigid panels for permanent installs, EcoFlow 220W bifacial panels for maximum output per square foot, and Jackery SolarSaga 100W as a portable supplement. MPPT charge controllers from Victron, Renogy, and EPEVER are compared for efficiency and data logging capability. Diesel & Propane Heaters for Van Life Heating is the first thing that separates comfortable van life from miserable van life in cold climates. We test diesel parking heaters — the Chinese-manufactured units sold under Vevor, Hcalory, and other brand names, plus the premium Webasto and Espar units — for startup reliability at temperature, altitude performance, fuel consumption, noise levels at 1 meter, and failure modes. Key finding: the Chinese diesel heaters work well with proper installation (fuel line routing and glow plug quality matter enormously) but have higher failure rates in the first year than premium units. We cover the full installation process, common failure fixes, and when the premium price of a Webasto is worth it. 12V Compressor Fridges & Coolers A compressor fridge is the single largest constant power draw in most van builds. We test 12V fridges for actual watt-hours per 24 hours at 90°F ambient temperature (the critical spec most reviews ignore), startup surge current, minimum operating voltage, and noise levels. Our top picks: BougeRV 30-Quart for compact builds under 130W/day power budget, Iceco VL45 for mid-size builds, and ARB Elements for the most power-efficient large-capacity fridge we've tested. Roof Vent Fans — Maxxair vs. Fantastic Fan A roof vent fan provides cooling, ventilation, and moisture control — critical for preventing condensation and mold in a van. The two dominant brands are Maxxair and Fantastic Fan. We install and run both for 6 months, comparing CFM airflow, rain sensor reliability, remote control range, and power consumption. Key finding: Maxxair's dome cover allows use in rain without manually closing; Fantastic Fan's remote is more reliable. Both are meaningfully better than budget alternatives in CFM per watt efficiency. Portable Showers & Water Systems Van water systems range from a single 5-gallon jug with a hand pump to a full plumbed system with a pressure pump, 25-gallon fresh tank, grey water tank, and propane water heater. We cover the full spectrum: Nemo Helio pressure shower for simple setups, 12V pressure pump systems for plumbed builds, and tankless propane water heaters (Camplux, Eccotemp) for hot water on demand. Our grey water guide covers legal disposal requirements by state and the most compact collection solutions for stealth camping. Portable Toilets & Composting Systems Toilet solutions determine where you can camp (dispersed land vs. van-legal parking). We test portable cassette toilets, composting toilets (Nature's Head, Air Head), and bucket systems for odor containment, capacity per dump/emptying cycle, and real-world use experience. The Nature's Head wins on long-term odor control but requires urine diversion that some users find inconvenient. Cassette toilets are easier to use but require disposal at dump stations. Van Life Internet — Hotspots, Starlink, and Data Plans Remote work from a van requires reliable internet. We test mobile hotspot devices (Netgear Nighthawk, GL.iNet) with T-Mobile, Verizon, and AT&T data plans for coverage in rural areas, data throttling behavior, and power consumption. Starlink RV offers satellite coverage for truly remote areas at a higher subscription cost and power draw (50–75W continuous). Our connectivity guide includes coverage maps by carrier, data plan comparisons, and signal booster options for weak cellular areas. Van Conversion Guides by Vehicle Mercedes Sprinter conversion — The most popular full-time van; high roof advantage, wide body options, diesel reliability Ram ProMaster conversion — Front-wheel drive advantage for winter, lower cost than Sprinter, more interior width Ford Transit conversion — Middle ground on price, AWD option, excellent parts availability Chevy Express/GMC Savana — Budget builds, high-roof aftermarket options, V8 reliability Frequently Asked Questions How much solar do I need for a van build?

Calculate your daily watt-hour consumption first: a 12V fridge (BougeRV 30qt) uses ~40–60Wh/day in moderate temps; a laptop uses ~30–60Wh per charge; LED lighting uses ~5–15Wh/day; phone charging ~10–15Wh. A typical work-from-van setup uses 200–400Wh/day. For reliable solar charging in 4–6 hours of peak sun, you need 1.2–2× your daily consumption in solar wattage — so 300–400W of panels for a 200–300Wh/day build. In winter or cloudy climates, add 50–100% capacity.

What is the best diesel heater for a van?

For budget builds, the Vevor 8kW diesel heater with upgraded fuel pump and glow plug is our top recommendation under $200. For reliability-first builds, the Webasto Air Top Evo 40 justifies its $800+ price with 5-year warranty and dealer service network. Key installation requirements for any diesel heater: fuel pickup from the main tank (not an auxiliary jerry can), proper exhaust routing away from the vehicle body, and air intake positioned away from exhaust gases.

How much does a full van conversion cost?

A minimalist van conversion (insulation, bed platform, basic electrical, no plumbing) runs $2,000–$5,000 in materials. A mid-level build with 200Ah LiFePO4, 400W solar, 12V fridge, diesel heater, and basic plumbing runs $8,000–$15,000. A premium build matching campervan standards costs $20,000–$40,000 in materials. Labor adds 30–50% if you hire out any portion. The biggest cost variables are battery bank size, solar capacity, and cabinetry materials.

Can I live in a van full time legally?

Van dwelling legality varies by city and county. Federal land (BLM, National Forest) allows free dispersed camping for 14-day stays in most areas. Many cities prohibit overnight vehicle dwelling, though enforcement varies significantly. Practical strategies: rotate parking areas every few nights, use a stealth van build (no obvious modifications visible from outside), and keep a Harvest Hosts or Thousand Trails membership for reliable overnight parking. States with the most van-friendly laws: Oregon, Nevada, New Mexico, and most rural Western states.