The Complete Buyers Guide To Caravan Solar Systems

Solar panels are the primary way most Big Lappers recharge their batteries while free camping. With no mains power and the engine off, solar is your only source of free, silent energy. The right solar setup can keep your batteries topped up indefinitely in good conditions, which means genuine independence from caravan parks and generators.

But solar has limits. Cloudy days, shade, winter sun angles, and dirty panels all reduce output. Understanding those limits and sizing your system accordingly is the difference between a solar setup that works and one that leaves you short.

How Caravan Solar Works

Solar panels convert sunlight into DC electricity, which is fed through a charge controller into your house battery. The charge controller regulates the voltage and current to safely charge the battery without overcharging it. The panels produce power whenever sunlight hits them, but output varies dramatically with conditions.

A 200W panel doesn’t produce 200W all day. That’s the peak rating under ideal laboratory conditions (direct noon sun, 25°C panel temperature, no shade). In the real world, you’ll get peak output for maybe two to three hours around midday, with lower output in the morning and afternoon. On a good sunny day in northern Australia, a 200W panel might generate 60 to 80Ah over the full day. In overcast southern Tasmania in winter, the same panel might produce 15 to 25Ah.

The practical rule for Australia: expect your solar panels to produce roughly 4 to 6 amp-hours per 100W of panel per day in good conditions. In winter or overcast weather, halve that.

Fixed Panels vs Portable Panels

Fixed (Roof-Mounted) Panels

Permanently mounted to your caravan roof, fixed panels are always connected and always working. You park, and they start charging. No setup, no cables to run, no adjustment needed. Most new caravans come with 160W to 400W of fixed solar on the roof.

Pros: Zero effort, always producing, can’t be stolen, don’t take up storage space.

Cons: Can’t be angled toward the sun (flat-mounted panels lose 15 to 30% efficiency compared to tilted panels), shaded when parked under trees (which you’ll want to do in summer), and output drops when the roof is hot (panel efficiency decreases as temperature increases).

Portable (Folding) Panels

Freestanding panels that you set up on the ground and connect to your van via an Anderson plug or similar. You can position them in full sun while the van sits in shade, angle them toward the sun for maximum efficiency, and move them throughout the day to follow the sun.

Pros: Can be positioned in sun while van is in shade, can be tilted for optimal angle, moveable throughout the day, supplement fixed panels.

Cons: Require setup and pack-up, take up storage space, can be stolen if left unattended, cables running across the campsite are a trip hazard.

The ideal setup for most Big Lappers is a combination: fixed panels on the roof for effortless baseline charging, supplemented by a portable panel for when you need extra input or when the van is parked in shade.

Solar Charge Controllers: MPPT vs PWM

The charge controller sits between your panels and your battery, regulating the charge to prevent overcharging and to maximise the energy harvested from your panels. There are two types:

PWM (Pulse Width Modulation): Basic controllers that essentially “switch” the connection between panel and battery on and off rapidly to regulate charging. They’re cheap ($30 to $80) and work, but they waste a significant portion of the panel’s potential output. A PWM controller typically harvests 65 to 75% of your panel’s theoretical output.

MPPT (Maximum Power Point Tracking): Advanced controllers that actively track the optimal voltage/current combination from your panels and convert it to the optimal charging voltage for your battery. They harvest 90 to 95% of your panel’s potential output, which translates to 15 to 30% more energy from the same panels compared to PWM. They’re more expensive ($150 to $500) but the extra energy harvested means you need fewer panels to achieve the same result.

For any system over 200W, an MPPT controller pays for itself in improved efficiency. For smaller systems (a single portable panel, for example), a PWM controller is adequate.

How Much Solar Do You Need?

The answer depends on your daily power usage and your battery capacity. As a starting point:

Light use (couple, LED lights, fridge, phone charging, no inverter): 50 to 70Ah/day. You need 200 to 300W of solar to replace this daily in good conditions.

Moderate use (couple or small family, fridge, lights, phones, occasional inverter use for coffee/laptop): 70 to 100Ah/day. You need 300 to 500W of solar.

Heavy use (family, fridge, lights, multiple devices, regular inverter use, TV, working remotely): 100 to 150Ah/day. You need 500W+ of solar, plus a generator or very large battery bank for overcast days.

These are guidelines for sunny conditions in most of Australia. If you’re travelling southern states in winter, increase by 30 to 50%. If you’re travelling the Top End in the dry season, you’ll have more sun than you know what to do with.

A practical approach: start with what your van has. Track your actual usage (a battery monitor makes this easy). If your batteries aren’t fully charged by mid-afternoon on a sunny day, you need more solar. Add a portable panel first; it’s the cheapest and most flexible upgrade.

Product Recommendations

Fixed Panels

For roof-mounting, glass monocrystalline panels are the standard. They’re durable, efficient, and designed to sit permanently on your van. A few worth considering:

Redarc 200W Monocrystalline: Australian-designed and extremely popular in the caravan market. High efficiency, slim profile, and well-suited to roof mounting. Redarc panels are fitted by many caravan manufacturers as standard. Around $350 to $450 per panel.

Enerdrive 190W Mono Fixed Panel: A solid mid-range option for roof mounting. Pairs well with Enerdrive charge controllers and batteries. Around $300 to $380.

Renogy 200W ShadowFlux Fixed Panel: Worth considering if shade is a concern. The ShadowFlux cell design handles partial shading better than standard panels, which makes a real difference when you’re parked under trees but still want some sun on the roof. Around $300 to $400.

KickAss 250W Fixed Glass Panel: Good value per watt for a larger fixed panel. If your roof has the space, the step up to 250W for a similar price to a 200W panel from other brands is worth taking. Around $250 to $350.

Portable (Folding) Panels

Portable panels come in two main forms: rigid folding panels (glass or semi-flexible cells in a folding frame) and solar blankets (flexible cells sewn into a fabric mat). Blankets pack down smaller and are lighter; rigid panels are generally more durable and slightly more efficient. Both work well.

Redarc 200W Folding Panel: The benchmark portable panel for caravanning. Folds in half, comes with an integrated stand for angle adjustment, and includes a 15A PWM controller in the carry bag (upgradeable to MPPT via a separate unit). Excellent build quality and a strong carry case. Around $600 to $750.

Renogy 200W Portable Folding Panel: A well-regarded alternative at a lower price. Good output, solid construction, and a popular choice for Big Lappers who want reliable portable power without paying Redarc prices. Around $350 to $450.

Victron 175W Folding Panel: Slightly smaller but premium Victron quality. Pairs perfectly with Victron MPPT controllers. Around $500 to $600.

Dune 4WD 250W Slim Folding Panel: A good value option from Anaconda that punches above its price point. The slim folding design stores easily, and 250W is a useful bump over the standard 200W panels. Around $250 to $350.

Solar Blankets

Solar blankets deserve their own mention. They pack down to roughly the size of a sleeping bag, weigh next to nothing compared to rigid panels, and can be draped over a vehicle bonnet or laid out on the ground. The trade-off is slightly lower efficiency and less durability over the long term. For Big Lappers tight on storage space, they’re an excellent option.

iTechworld 400W PRO Solar Blanket with Raptor Skin: The top-of-the-line blanket option. 400W in a pack-flat format is impressive, and the Raptor Skin outer layer adds meaningful durability. If you want maximum portable wattage without the bulk of rigid panels, this is the pick. Around $600 to $750.

REDARC 240W Monocrystalline Solar Blanket: Redarc’s blanket uses monocrystalline cells for better efficiency than the polycrystalline blankets you’ll find at the budget end. Australian-backed warranty and support. Around $500 to $650.

MPPT Charge Controllers

Victron SmartSolar MPPT 100/30: Handles up to 440W of solar (at 12V) with Bluetooth monitoring via the Victron Connect app. Highly efficient, reliable, and well-supported. The most recommended MPPT controller in the caravan community. Around $200 to $280.

Enerdrive MPPT 40A Solar Controller with Display: The built-in display sets this one apart. If you want to see exactly what your solar is doing without pulling out a phone or separate monitor, this is worth the extra cost. Handles up to 480W at 12V. Around $280 to $380.

Redarc MPPT Solar Regulator: Australian-made, available in various sizes to suit your system. Integrates with the Redarc RedVision monitoring system. Around $250 to $400 depending on capacity.

Getting The Most From Your Solar

Keep panels clean. Dust, bird droppings, and grime reduce output noticeably. A quick wipe with a damp cloth every few days makes a measurable difference, particularly on outback roads where dust coats everything.

Angle portable panels toward the sun. A panel tilted toward the sun produces up to 30% more than the same panel lying flat. In winter, the sun is lower; increase the tilt angle. In summer, a flatter angle works. Most portable panels have adjustable legs for this.

Avoid shade. Even partial shade on one cell of a solar panel can reduce the output of the entire panel dramatically (not just the shaded cell). Park portable panels well clear of trees, awnings, and anything that casts a shadow.

Use an MPPT controller. If you’re still running a PWM controller, an MPPT upgrade harvests 15 to 30% more energy from the same panels.

Monitor your system. A battery monitor (like the Victron SmartShunt) shows you exactly how much solar is coming in and how much you’re using. This lets you make informed decisions about when to move panels, when to conserve, and when you’ve got plenty.