Flexible solar cells are rapidly advancing, achieving record efficiencies and opening up new possibilities for solar energy applications. Recent breakthroughs suggest they could soon rival, and potentially replace, traditional rigid solar panels in many scenarios.

One of the most significant advancements has been in improving the efficiency and durability of flexible solar cells. Chinese scientists have developed a novel technique to enhance the adhesion between the top and bottom layers of tandem solar cells, which pairs a perovskite top layer with a copper indium gallium selenide (CIGS) bottom layer. This innovative approach uses smart solvent manipulation and a seeded layer to create a stronger bond between the layers, resulting in increased efficiency and the ability to withstand thousands of bending cycles without significant performance loss. As of April 2025, a team fabricated a 1.09 cm² flexible monolithic perovskite/CIGS tandem solar cell achieving a stabilized efficiency of 24.6% (certified at 23.8%), competing with top rigid counterparts.

Researchers at the Korea Institute of Energy Research (KIER) have also achieved a power conversion efficiency of 23.64% with their ultra-lightweight flexible perovskite/CIGS tandem solar cells, which is the highest reported efficiency for this type of flexible solar cell to date. These cells are exceptionally lightweight and can be easily attached to curved surfaces, making them suitable for use in buildings, vehicles, and aircraft. The lift-off process they developed involves fabricating the solar cell on a glass substrate coated with a polyimide layer and then separating it, allowing for stable manufacturing.

These advancements address some of the key limitations of earlier flexible solar cells. Flexible panels weigh approximately 20% as much as rigid panels. In the past, flexible solar panels were significantly less efficient than rigid panels, however, today, you can purchase flexible solar panels that are just as efficient as rigid solar panels. Also, they can be bent up to 50 degrees without damage. Their flexibility, lightweight nature, and ease of installation make them ideal for applications where traditional panels are unsuitable. For example, they can be attached to surfaces that cannot support the weight of rigid panels, such as car roofs or flexible surfaces.

Despite these advantages, flexible solar cells have historically faced challenges. Flexible panels will cost more than rigid ones, have lower power generation efficiency, and likely need to be replaced sooner. Also, because flexible panels are typically mounted directly to the surface they are on, they also have no air gap to help cool them. On hot days the panels can get very hot, and when they do, produce less power, losing up to 20% of their rated output. However, recent innovations are addressing these issues. The development of tandem solar cells, which combine different materials to capture a broader spectrum of sunlight, is significantly boosting efficiency. Moreover, new manufacturing techniques are improving the durability and lifespan of flexible cells, making them more competitive with rigid panels.

The potential applications for high-efficiency flexible solar cells are vast. They can be integrated into building facades, windows, and even clothing, turning everyday objects into power generators. The transport sector could also benefit greatly, with flexible solar cells seamlessly integrated into car roofs, airplane wings, and the sides of trains to supplement their power needs. Moreover, flexible solar cells are ideal for portable devices and off-grid applications, providing a reliable source of energy in remote locations or during emergencies.

Researchers from the University of Sheffield and Power Roll are developing flexible solar cells for rooftops and surfaces using plastic film with a solution processable semiconductor. The researchers use plastic film filled with the perovskite material instead of silicon. Small indentations on the film allow the invention to capture more sunlight.

While challenges remain, the latest advancements in flexible solar cell technology are paving the way for a more versatile and accessible solar energy landscape. As efficiencies continue to rise and production costs fall, flexible solar cells are poised to become a mainstream alternative to rigid panels, driving the widespread adoption of renewable energy and accelerating the transition to a cleaner, more sustainable future.