Fashion designer Pauline van Dongen has unveiled a groundbreaking flexible, solar-energy-generating textile called Heliotex, which serves as the striking canopy for her pavilion at Dutch Design Week. The innovative material represents a major leap forward in sustainable design technology, combining fashion expertise with renewable energy solutions.
The Umbra Pavilion is currently on display in Eindhoven's Strijp-S district as part of the city-wide Dutch Design Week festival. The architectural installation features a distinctive sky-blue, kite-like canopy made from Heliotex, which incorporates recycled polyester yarn woven with 150 organic photovoltaic (OPV) solar cells. This unique combination allows the structure to harness solar energy during daylight hours and store it for use after dark.
"What we're doing is making solar technology really pliable and lightweight," van Dongen explained during a tour of the pavilion. "We're turning it into a design material that you could apply to all kinds of places where the traditional silicon solar panels that we all know don't work because they're heavy and rigid and 'one size fits all'." The designer emphasized that this flexibility opens up numerous applications that were previously impossible with conventional solar technology.
Formerly known as Suntex, Heliotex was developed through a collaboration between van Dongen and Dutch manufacturer Tentech. The technical textile spans an impressive 40 square meters and incorporates eight square meters of solar cells connected to an integrated energy storage system. This large-scale application sets Heliotex apart from other solar-integrated clothing designs, as it was specifically engineered for architectural applications such as building cladding or festival tents.
Van Dongen envisions significant potential for the material in building retrofits and urban sustainability projects. "If you think about upgrading buildings, especially because a lot of buildings aren't climate-neutral or climate positive, but you also don't want to demolish them, you could build a second skin facade around a building," she noted. "If you made that skin out of textile, it could also be a translucent mesh textile, so you could still look out of the window without any problems."
The development of Heliotex required overcoming numerous technical challenges to ensure durability and safety. The material was engineered to resist weathering and UV radiation while maintaining fire-retardant properties. This involved creating a specialized coating with sufficient tensile strength while avoiding toxic polyvinyl chloride (PVC), which van Dongen said would trap the solar cells woven into the fabric. "We designed a fabric structure that holds them in place," she explained. "Floating sections of monofilament yarns hold the panels in place, but they're not glued. They're not stuck to the textile. So they can also be easily replaced, repaired or recycled."
Currently, the woven solar panels in Heliotex produce 53 watts of energy per square meter, which is approximately one-fifth of the output generated by traditional silicon solar panels. However, van Dongen's team is actively working to improve this efficiency in collaboration with researchers from a Danish university, who have already managed to double the output per square meter in laboratory tests. Despite the current lower efficiency, van Dongen emphasizes that Heliotex targets applications where traditional solar panels wouldn't be suitable anyway.
"There are still barriers and challenges, but we're applying this textile in places where traditional solar panels wouldn't need to be applied anyway," she explained. "We're not competing with them, so to say." This approach allows the technology to expand solar energy generation into previously untapped areas while complementing rather than replacing existing solar infrastructure.
The Umbra Pavilion's design maximizes both energy generation and visitor experience. The Heliotex canopy is strategically angled to cast shadows over the rest of the pavilion, creating a comfortable environment for visitors. The structure includes circular bench-style seating where people can sit and experience the innovative solar technology firsthand while learning about its potential applications.
Dutch Design Week continues to showcase cutting-edge design innovations across Eindhoven. This year's program includes various exhibitions, such as a pavilion exploring the lives of asylum seekers in the Netherlands by local organization De Wachtkamer. Last year's festival featured notable presentations including the Specimen show by Dutch Intervals, which showcased reworked furniture made from tree branches, copper fossils, and LCD-style graphics, demonstrating the festival's commitment to sustainable and innovative design solutions.
Dutch Design Week 2025 runs from October 18 to 26, 2025, at various locations throughout Eindhoven, Netherlands, providing a comprehensive platform for designers, innovators, and visitors to explore the future of sustainable design and technology integration.
