Flexible monocrystalline or polycrystalline silicon solar panels do not have the durability and performance compared to rigid solar panels. Being bonded directly to roofs, the panels cannot dissipate heat from their underside, causing thermal decay of the solar cells.
CIGS solar panels are made of successive layers of Cadmium, Indium, Gallium, and Selenide, forming a thin, flexible solar panel that will not crack as the elements are all metallic. The panels have an adhesive layer on the back and can be applied directly to clean surfaces.
CIGS solar panels are ideally suited for use in the leisure market. They come in various sizes, and their innovative peel-and-stick adhesive backing makes installation easy and eliminates the need for expensive heavy mounting systems. Their key features are:
- Efficient – up to 23%
- Flexible – can be rolled up for transport
- Lightweight – up to seven pounds lighter than other flexible panels
- Low profile – less than half-inch thick
- Easy to install – adhesive backing peel and stick
CIGS solar panels were developed for military applications initially and can sustain gunshots and still produce power. They are designed for the rigors of off-grid mobile installations and are the first flexible solar panels to have a ten-year performance warranty.
Let’s look at the CIGS solar technology more closely and compare it to other silicon-based flexible solar panels.
How Long Do Flexible Solar Panels Last In Reality?
Even the top flexible solar panels from a flagship brand like Sunpower only carry a limited manufacturer warranty. These panels are fitted with crystalline silicon solar cells prone to mechanical damage and usually do not last longer than five years.
Numerous cruisers and van lifers have complained about the poor service life of flexible solar panels. These solar panels cannot flex more than 30 degrees and cannot be walked on without being damaged.
Solar installation experts like Will Prowse have conducted many tests on flexible solar panels and warn that the performance rapidly deteriorates and the panels become useless after five years of operation.
What Makes CIGS Flexible Solar Panels So Good?
The thin-film components that make up the CIGS solar panels are metallic and thus not brittle and can be rolled up. The CIGS chemistry is very efficient at generating solar power and can achieve up to 23% efficiency. The CIGS panel can withstand mechanical damage and remain functional.
The CIGS solar panel technology was initially developed for military applications where basic requirements were easy deployment and rugged durability. The panels can be rolled up for transportation and are strong enough to be walked on or continue working after taking a bullet.
Due to their specialized application and low volume supply, CIGS solar panels have initially been costly, but their costs have dropped to similar levels as conventional flexible solar panels.
Conventional flexible solar panels are stuck onto surfaces using 3M Dual Lock adhesive tape or Sikaflex 221. Both application methods are suitable and create a secure bond to various surfaces.
CIGS solar panels are manufactured with a self-adhesive peel-off backing that makes installation easy and secure. The peel-and-stick application requires that the surface to which the CIGS panel is stuck is clean and wiped down with isopropyl alcohol.
Once the surface is clean, the peel-off backing strip on the bottom side of the CIGS solar panel can be peeled off as the sticky contact surface is applied. Use a towel to firmly press down and wipe down the solar panel to expel any air pockets between the two surfaces.
CIGS Vs. Silicon-Based Flexible Solar Panels
A key aspect of the performance of solar panels is that they must be able to dissipate heat to maintain a high-efficiency level. Rigid solar panels are always installed with an air gap of two to three inches underneath to allow for cooling.
With a stick-on flexible solar panel, there is no air gap underneath the panel, thus losing efficiency as the panel becomes warmer and cannot dissipate the heat.
The metallic composition of the CIGS thin-film solar panel is better at dissipating heat and also generates power from a much broader range of visible light frequencies and intensities.
| CIGS Solar | Silicon Crystal Solar | |
| Annual Power Yield | 10-20% higher | Standard |
| 10% Shadows effect | reduce the production with around 10-20% | reduce the production with Around 60-80% |
| CO2 During Production | Uses significantly less energy to produce than crystalline cells | Uses a lot of energy during the production phase |
| Chemistry | Copper Indium Gallium and Selenide. | Silicon |
| Flexibility | Very flexible | Semi-flexible, due to the wafer construction |
| Installation | Easy peel & stick backing | Use 3M or Sikaflex glue system |
| Micro cracks | Metallic layers do not crack | Due to the wafer build, the crystalline modules are vulnerable to micro cracks which will decrease efficiency and might in extreme cases cause fire. |
| Durability | Due to the layered construction, there is no wafers to crack or damage | Wafers are fragile and crack due to vibrations in boats and cars or from the pressure from Snow and wind. |
| Lifetime | Same on moving and non-moving installations | Wafers break/crack on moving installations (boats/cars/etc.) and the output deteriorate much faster than on non-moving installations |
| Temperature impact | Power production decline approx. 0,3% per degree Celsius the temperature increases. | Power production decline approx. 0,6% per degree Celsius the temperature increases. |
| Efficiency | Up to 23% | Up to 23% |
| Weight | 2,9 kg/m2 | 5,5 kg/m2 |
| Typical warranty | 5- or 10-years workmanship. 25 years power loss | 3- or 10-years workmanship. 25 years power loss |
| Appearance | Typically black, but can be produced in all colors and even transparent | Black for mono crystalline and blueish for poly crystalline |
CIGS solar panels are a relatively new technology that has only been commercially available for the past three years. The ease with which these panels can be transported and installed makes them the ideal solution for mobile off-grid applications.
They are 47% lighter, thinner, more flexible, and more durable than conventional silicon-based solar panels. As the supply of CIGS technology solar panels increases, the cost decreases.
CIGS solar panels require less energy to manufacture and are easy to recycle due to their metallic composition. They are produced in various shapes and sizes and are easy to install due to the peel-and-stick adhesive backing.
