Umbra Pavilion: Where Solar Energy Becomes Tangible

Oct 25, 2025
2 min read

Presented during Dutch Design Week 2025, the Umbra Pavilion by Studio Pauline van Dongen and Tentech transforms sunlight into shade and energy into light. This architectural installation showcases Heliotex — a lightweight, flexible solar textile that not only provides shade but also generates clean energy, demonstrating how design can make cities both cooler and more vibrant in a warming climate.

From Sun to Shade, from Energy to Light

The pavilion offers a glimpse into a future where solar energy is woven into daily life — tangible, shared, and accessible to all. Rising like a kite in the heart of Eindhoven’s Ketelhuisplein, the sky-blue textile canopy invites visitors to pause and reflect beneath its organic form. By day, it provides cooling shade while harvesting sunlight through its woven solar cells; by night, the stored energy returns, bathing the space in atmospheric light.

Design as a Driving Force for Climate and Energy

More than a functional structure, the Umbra Pavilion highlights the crucial role of design in climate adaptation and the energy transition. In increasingly warmer cities, Heliotex offers both cooling and shading. Visitors experience firsthand how solar textiles work, discovering that this material is not only a technical innovation but also a cultural expression of sustainability — a way to give the energy transition an emotional and social dimension.

The City of Arnhem, a leader in climate adaptation, will also present the Umbra Pavilion in the summer of 2026. There, Van Dongen and the city will explore how Heliotex can reduce perceived temperatures in urban spaces where greenery is not an option — offering an aesthetic and energy-generating shading solution that blends with the city and its people.

Flexible Solar Textile Shaping Architecture and Design

Heliotex integrates organic photovoltaic cells (OPVs) directly into the fabric, allowing flexibility in shape, color, pattern, and density. As a technical textile, it is suited for a wide range of architectural applications — from façades and public shade structures to pavilions, canopies, and festival tents.

In the Umbra Pavilion, Heliotex spans 40 m², embedding 147 OPV modules that cover 8 m² of solar cell area, with a total energy storage capacity of 3,000 W. The pavilion itself stands nearly 10 meters tall and covers a 190 m² floor area.

Developed over four years by designer Pauline van Dongen in collaboration with Tentech, Heliotex marks its first architectural-scale application through the Umbra Pavilion — a milestone in the merging of design, material innovation, and renewable technology.