Umbra Pavilion

From Sun to Shade, from Energy to Light

The pavilion offers a glimpse of a future where solar energy is woven into daily life; tangible, shared, and accessible to all. In the heart of Ketelhuisplein, the textile canopy unfolds as an organic form, rising like a kite into the blue sky. By day, it offers cooling shade and a place to pause and reflect, while its woven solar cells harvest the sun’s energy. As evening falls, the stored energy returns, enveloping the pavilion in atmospheric light.

The Umbra Pavilion aims to raise awareness of climate adaptation and the energy transition through the power of design. More than just functional, the pavilion serves to educate visitors about the need for alternative energy solutions in cities.

Design as a Driving Force for Climate and Energy

The Umbra Pavilion demonstrates how design plays a vital role in climate adaptation and the energy transition. In cities where summer heat is increasingly tangible, heliotex offers shade and cooling. The pavilion invites visitors to experience the workings and effect of solar textiles firsthand. In doing so, the material reveals itself as more than a technical solution: it lends the energy transition the cultural meaning it cannot do without.

The City of Arnhem, a frontrunner in climate adaptation, and Van Dongen will also present the Umbra Pavilion in the summer of 2026. There they will explore how heliotex, as a shading textile, can help lower perceived temperatures in the city center. In places where greenery is not an option, the solar textile offers an energetic and aesthetic shading solution that fits the city and its inhabitants.

Flexible Solar Textile Shaping Architecture and Design

Heliotex weaves organic solar cells (OPV’s) directly into the fabric, making the material flexible in form and variable in color, pattern and density. As a technical textile, it is suited for applications in the built environment such as shading cloths and shade structures for public spaces, building façades, and canopies or tents for festivals.

In the Umbra Pavilion, heliotex extends across 40 m² with 147 OPV modules covering a total of 8 m² and an energy storage capacity of 3,000 W, integrated into a pavilion with a floor area of 190 m² and a height of nearly 10 meters.

Heliotex is an initiative by designer Pauline van Dongen. Over the past four years, her studio has collaborated with Tentech on the development of this solar textile, which is now being applied for the first time on an architectural scale.