Solar panels for vans

How van solar works in plain terms

Solar panels convert sunlight into DC power that feeds a charge controller, which then tops off a house battery bank. Most camper vans run 12 volt or 24 volt systems, and almost every device on board ultimately draws from stored energy in the batteries. The simplest way to size solar is to calculate daily energy use in watt hours, then divide by the average peak sun hours where you travel. Add headroom for cloudy days and real world losses, and you have a practical target for total panel wattage on the roof or as a portable array.

Start with a usage list. A compressor fridge might consume 300 to 600 watt hours per day depending on size and climate. Add lighting, fans, a water pump, device charging, and any AC loads that run through an inverter such as induction cooking or a laptop brick. If your total is 1000 watt hours and you expect 5 peak sun hours in summer, a 200 watt array would be theoretical. In practice, plan closer to 300 to 400 watts to cover heat, shading, wiring losses, and controller inefficiencies.

Panel types and wattage realities

Rigid monocrystalline panels deliver the best longevity and efficiency for vans. They shed heat better, resist abrasion, and keep output more stable over time. Flexible panels are lighter and can conform to curves, but they typically run hotter and degrade faster if bonded directly to a roof with no airflow. Portables, often called suitcases, let you park in the shade while the panels sit in the sun; they are great for shoulder season camping but require setup and security awareness.

Real world wattage rarely matches the label. Heat reduces voltage, partial shade can collapse current, and a dirty module can trim five to ten percent of output. Expect your system to perform to a seasonal average rather than a single rating. Planning with conservative assumptions is the surest way to keep batteries happy.

Picking panels and mounting them right

Roof space dictates layout, and roof accessories set the rules. Measure available flat zones after fans, racks, antennas, and skylights. Fewer larger modules simplify wiring and maximize useable area. Mounting that creates a small air gap under the panel improves cooling and output across hot summer days. Tilt mounts can boost winter production when the sun rides low, but they add complexity and height. Most van owners favor low profile fixed mounts for clearance, reliability, and simplicity.

Cable routing should be watertight and strain relieved. Use dedicated roof cable glands with UV safe sealants. Route wires inside protective loom away from sharp edges and heat sources. Plan a service loop so panels can be lifted for cleaning or maintenance without stressing connectors. If you camp in dusty or coastal regions, a soft brush and gentle rinse keep glass clear and production consistent.

Roof layout, shade, and airflow

Shadow from a rack tube or cargo box can cut panel output sharply. Series wired strings are especially sensitive to partial shade on any single module. Keep obstructions out of the panel footprint or create spacing that prevents cross shadows at mid day. Maintain airflow beneath the panels to reduce heat soak; even a half inch gap helps. When using a roof rack, consider crossbar placement that supports frames at manufacturer recommended points while leaving open channels for air to move.

Battery, controller, and inverter choices

Match your charge controller to battery chemistry and array voltage. MPPT controllers track voltage to squeeze more energy from panels across changing temperatures and light. They routinely deliver ten to thirty percent more energy than PWM in van applications. In small arrays up to 200 watts, PWM can still work, but MPPT pays for itself quickly when space is limited. For wiring, series raises voltage and can reduce current and cable size, while parallel maintains lower voltage and preserves output when one panel is shaded. Many vans blend both with fusing on each branch.

Lithium iron phosphate remains the preferred battery for weight, depth of discharge, and cycle life. A quality BMS protects cells from over charge, low voltage, and temperature extremes. AGM batteries can be a budget choice, but they are heavier, charge slower, and offer less usable capacity. If you plan to run AC loads, choose a pure sine wave inverter sized for continuous draw and surge. An induction cooktop may need 1500 to 1800 watts with short surges over 2000 watts; size cables and protection accordingly.

Wiring, protection, and monitoring

Use marine grade tinned copper wire, calculated for current and distance to keep voltage drop under three percent on critical runs. Place fuses or breakers close to sources like the battery and array. Add a master disconnect for service. A shunt based battery monitor tells you state of charge, amps in and out, and cumulative consumption so you can adjust habits before the lights dim. Consider a DC to DC charger from the alternator to supplement solar on stormy stretches or winter travel, and shore power charging for storage or quick turnarounds.

A complete van system blends solar, alternator charging, and optional shore into one coherent plan. By viewing the solar array as a steady charger rather than a single solution, you will build a power system that remains reliable in all seasons.

Strong solar is one part of a well designed build. When you need professional integration that accounts for roof layout, real world shading, charging sources, and future service, expert installation makes the difference. OZK Customs designs and installs van solar systems that are clean, safe, and sized to your travel rhythm from our shop in Fayetteville Arkansas. We build around your usage targets, test under load, and deliver a system that is easy to understand and maintain on the road.

Bold moves start with a clear plan. If you are exploring an adventure van, see our Recreational vans to understand platforms and upfit paths. For a ground up electrical and interior package, our Custom build van page outlines how we turn a concept into a finished rig. Shopping for a finance friendly platform with solar ready options? Visit Mainstream vans to see what fits your timeline.

Looking for next steps Tell us your daily watt hours, where you travel, and what you want to power. We will translate that into a right sized array, MPPT controller, lithium storage, and tidy wiring that serves you for years. Your trip should be about the view, not the voltmeter.

Final note on what we do OZK Customs builds complete adventure vans and installs professional grade power systems. We do not rent vans or offer DIY build assistance. We design, fabricate, and integrate so your van works the first time and every time.