Flexible vs Rigid Solar Panels: Which One Is Right for You?

Searching for solar panels for a boat, camper van, or other mobile setup? If so, remember, choosing panels for these applications is not only about finding high-wattage solar panels; you should also consider other factors, such as available roof space, roof shape, weight limitations, budget, and installation preferences.

The right solar setup often starts with choosing between flexible vs rigid solar panels.

Rigid solar panels are installed slightly above the roof, whereas flexible solar panels are directly attached to the curved surfaces. Unlike rigid solar panels, flexible panels do not need traditional mounting hardware during installation.

So, which one should you choose? This guide presents a comprehensive comparison between flexible and rigid solar panels to help you make an informed decision.

Flexible vs Rigid Solar Panels: A Quick Comparison

The table below quickly compares flexible solar panels vs rigid panels.

Feature	Flexible Solar Panels	Rigid Solar Panels
Durability	Varies by construction and installation	Excellent
Weight	Much lighter	Heavier
Efficiency	Generally lower	Generally higher
Roof Shape	Best for curved surfaces	Suitable for flat roofs
Installation	Low-profile or adhesive mounting options	Racking/brackets required
Roof Penetration	Can avoid drilling	May need drilling
Heat Management	More heat buildup when installed flush	Better due to airflow underneath
Long-Term Value	Best when shape and weight matter	Usually better
Profile	Very low	Higher
Best For	Lightweight, curved, low-profile applications	Permanent systems and flat roof

What are Flexible Solar Panels?

Flexible solar panels come with lightweight, thin construction that allows them to bend and fit around certain curved surfaces. These panels are suitable for camper vans, RVs, boats, and other similar applications where traditional panels are impractical.

They have a very low profile, which means they can sit close to the surface. Their lighter weight makes them a good choice when roof weight is a concern.

flexible solar panel

What are Rigid Solar Panels?

Rigid solar panels are conventional solar panels, particularly installed on homes and commercial buildings. They are also used on many RVs. These panels are covered with glass and are mounted on aluminum frames.

For RV installation, rigid panels are installed above the roof using rails, brackets, or other mounting equipment. This creates an air gap between the roof and solar panels.

Which Type of Solar Panel Is Best for Your Setup?

The selection of the right solar panel mainly depends on the type of your RV’s roof, installation preferences, weight limitations, and long-term power requirements. Let’s look at a few scenarios to better understand whether rigid or flexible panels are the better option.

Curved RV Roofs

Flexible solar panels perform better on curved RV roofs because they can fit gently curved surfaces without the need for the raised mounting structure that is used with conventional rigid solar panels. The low-profile design of flexible panels makes them easier to use in roof areas where installing rigid panels is often impossible.

Flat RV Roofs

Rigid solar panels are better for flat roofs, as they can be mounted securely with brackets. Moreover, these panels can be placed with an air gap beneath them to improve air circulation. This enables rigid panels to dissipate heat and perform better, especially in hot conditions.

Limited Roof Load Capacity

Does your RV roof have a limited load-bearing capacity? If yes, choose flexible solar panels because they are much lighter than framed rigid panels. They enable you to install a solar setup without adding much weight to the roof.

Need for Maximum Power Output

If your primary goal is to generate as much solar energy as possible, choose rigid panels as your first choice. You can easily find them in higher-output configurations. Moreover, you can mount them above the roof to provide good ventilation. The durable construction of rigid panels gives them improved performance for long-term outdoor use.

Low-Profile Installation

If maintaining a low-profile installation is important, flexible solar panels are the better choice. Unlike rigid panels that need appropriate mounting equipment (which increases overall height) to install the setup, thin construction helps flexible panels sit closer to the RV roof.

Avoiding Roof Drilling

If you don’t want to drill into your RV’s roof, look no further than flexible panels. Some flexible panels can be secured with adhesives instead of conventional fasteners and brackets. However, it depends on the product and the manufacturer’s instructions for installation.

Long-Term Use and Durability

If long-term durability is your priority, rigid panels are the best choice. Their framed construction and glass surfaces offer strong protection against physical wear and varying atmospheric conditions. Flexible panels can also perform well for years, but their life depends on factors like product quality, exposure conditions, and installation method.

How to Install Flexible Solar Panels on an RV Roof?

Have you decided that flexible solar panels are right for your RV? If so, perform the installation carefully. Though a flexible solar panel itself is lightweight, the installation needs to withstand high-speed winds, rain, temperature changes, and vibration. Here is how you can install flexible solar panels on your RV roof.

1. Check Your RV Roof

Check the material and condition of your RV roof. Materials (such as fiberglass, EPDM, and TPO) may vary from one RV to another. An adhesive can be suitable for one roof material, but not for the other. Don’t forget to check the RV manufacturer’s recommendations and the manufacturer’s installation instructions.

2. Plan the Panel Location

Position solar panels where they can receive the maximum sunlight. Avoid placing panels directly beneath or beside objects that can create shadows, such as antennas, air conditioning units, storage compartments, satellite equipment, and roof vents.

Since even a partial shade can significantly reduce power output, considering roof layout is crucial before installing flexible solar panels.

3. Clean & Prepare the Roof

This is what people often underestimate. Before installation, make sure that your RV roof is dry, clean, and free from incompatible coatings, dirt, oxidation, grease, and other contaminants that could prevent proper bonding.

Ensure the cleaning products you use are compatible with your roof membrane. A generic solvent or a household cleaner may not be safe for your RV roof. Poor surface preparation can cause panels to loosen over time.

4. Decide How to Secure the Panels

Manufacturers may recommend a compatible industrial mounting tape, adhesive, or brackets, considering your RV roof material and the panel design. Avoid using a generic construction adhesive or ordinary silicone. The mounting method must be compatible with both the RV roof and the panel backing.

Some flexible solar panel installations use a mounting method that creates an air gap beneath the solar panel. This eliminates or minimizes the heat buildup, one of the major drawbacks of flexible solar panels.

5. Route the Solar Cables

Make sure the solar cables reach the charge controller without creating an opening where water can enter. An appropriately sealed solar cable entry or a weatherproof roof gland is usually used for roof penetrations.

The entry point must be placed carefully. Plus, it should be sealed according to your RV roof and gland manufacturer’s instructions.

6. Connect the System

Solar panels are connected to the suitable solar charge controller. The charge controller is then connected to the RV battery system.

The charge controller must be properly sized for the battery bank and the panel array. Breakers or fuses should be installed if the manufacturer’s instructions and the system design require it.

If you are not very familiar with the RV electrical system, go for professional installation. Even a small mistake during wiring can lead to a safety hazard or equipment damage.

Final Words

Comparing flexible vs rigid solar panels shows that flexible panels are generally the better choice when you need a low-profile and lightweight solar setup that can fit a curved roof.

Before choosing between rigid and flexible panels, ensure you consider available roof space, roof material, daily power requirements, weight limitations, and the manufacturer’s installation instructions.

FAQs

Can I combine flexible and rigid solar panels?

Yes, you can combine flexible and rigid solar panels if the electrical specifications are compatible and if they are configured correctly using an appropriate charge controller.