Solar Blanket vs Rigid Solar Panel for 4WD Camping

The quick answer

Choose a solar blanket if you want something light and portable that you can move into the sun while you park in the shade. Choose a rigid panel if you want the most power for your money and somewhere permanent to mount it. Plenty of campers end up running both.

Solar blanket: flexible and portable

Folds down small and weighs very little.
Easy to move into the sun while the car or van stays in the shade.
Great for short trips and 4WDs without roof space.
Usually costs more per watt than a rigid panel.
Less durable. It needs care with wind, sharp ground and folding.

Rigid panel: permanent and powerful

More power for the money, with a lower cost per watt.
Tough enough for long off-road trips.
Charges whenever the vehicle is in the sun, including while you drive.
Heavier, and needs mounting space on a roof, rack or canopy.
Can't be moved into the sun if you camp in the shade.

How much solar do you need?

Start with your daily use. Many campers with a compressor fridge, lights and phone charging use somewhere around 40 to 70Ah a day. As a rough guide, 200W of solar can put back around 40 to 60Ah on a clear day, less in winter, cloud or partial shade.

So 200W suits a modest setup in good weather. If you stay put for longer, camp in winter or run more gear, 300 to 400W gives you more margin.

Getting the most from either

Use an MPPT controller set to your battery type. MPPT controllers usually harvest more from the same panel than PWM ones.
Watch the lead length. Panel voltage is higher than battery voltage, so a long lead from the panel to a controller near the battery loses less power than a long lead after the controller.
Avoid shade. Even partial shade on one part of a panel can cut its output a lot.
Angle portable panels toward the sun and move them through the day.
Keep them clean. Dust on the panel reduces output.

Which should you buy?

If you only buy one, choose a blanket for short trips and flexibility, or rigid for long stays and the most power per dollar. Running both gives you a roof panel charging all day plus a blanket to chase the sun at camp.