24.4% efficient flexible solar film brings frame-free power to US aerospace, transport

A 0.85 mm thick solar laminate featuring interdigitated back-contact (IBC) cells with an efficiency rating of 24.4% is now entering commercial production for industrial manufacturers. Developed by SolarWindow Technologies under the name ElectroFlex, the system delivers a power-to-weight ratio of roughly 73 W/kg. The company has released the hardware to Tier-1 original equipment manufacturers across the United States. Deliveries to selected industrial partners in North America and Asia will follow over the coming quarters. Five-layer composite structure The entire laminate relies on a five-layer composite structure that measures under a single millimeter in cross-section. At the top sits a 0.10 mm front encapsulant that protects the internal electronics from environmental wear. Right below this protective film lies a 0.16 mm layer of interdigitated back-contact (IBC) solar cells. Electrical conduction occurs through a 0.04 mm copper backing placed beneath the cells. Structural strength comes from a 0.30 mm composite laminate, which rests on a 0.25 mm rear substrate. This adhesive base allows the material to stick directly onto host surfaces. “ElectroFlex is an ultra-thin, ultra-lightweight, flexible solar product available today for manufacturers, bonding directly to flat and curved surfaces without racks, frames, or mounting hardware, across transportation, marine, aerospace, agricultural, infrastructure, and specialty vehicle applications,” said SolarWindow. Different mechanical approach Traditional silicon solar setups carry heavy structural penalties. They require thick tempered glass, metal perimeter frames, and elevated mounting racks to hold everything in place. These assemblies add considerable weight and create concentrated load points on host structures. ElectroFlex takes a different mechanical approach by acting as a flexible film. Because it bends easily, engineers can install it across complex curves, compound radii, and irregular contours. The lightweight profile allows energy generation on load-sensitive surfaces that cannot carry standard solar arrays. Common use cases include aircraft fuselages, drone wings, train exteriors, commercial truck bodies, and architectural membranes. SolarWindow delivers the technology as an engineered electrical system rather than an off-the-shelf part. The company supplies the wiring, wire harnesses, power-balancing units, and delivery circuitry required to collect and route the electrical current. Technicians from the company design the specific electrical routing and balance-of-system hardware for every individual installation. In transport and mobile machinery, this direct integration converts exterior bodywork into an auxiliary power source. The electricity harvested from the vehicle skin can run onboard systems, recharge battery banks, and reduce the fuel needed for auxiliary generators. Technical sheets and certification data The release of ElectroFlex broadens the technical work at SolarWindow, which previously focused on liquid coatings that turn building window glass into power-generating surfaces. The company plans to publish further technical sheets and certification data in upcoming announcements. According to chief executive Amit Singh, this release marks the first step in a wider program covering energy generation, storage, and power management. The firm is currently pursuing technology evaluations, supply agreements, and corporate partnerships to expand production.Get the latest in engineering, tech, space & science - delivered daily to your inbox.An active and versatile journalist and news editor. He has covered regular and breaking news for several leading publications and news media, including The Hindu, Economic Times, Tomorrow Makers, and many more. Aman holds expertise in politics, travel, and tech news, especially in AI, advanced algorithms, and blockchain, with a strong curiosity about all things that fall under science and tech.