Gips-Schüle research award for “Solar Gate”

Prof. Achim Menges, Head of the Institute for Computational Design and Construction (ICD) at the University of Stuttgart, and Prof. Thomas Speck from the University of Freiburg received the prestigious 2025 Gips-Schüle Research Award on the evening of December 2. The award is endowed with 50,000 euros and is presented by the Stuttgart-based Gips-Schüle-Foundation.

The Stuttgart architect and the Freiburg biologist received the award for their “Solar Gate” – a bio-inspired shading system that regulates the indoor climate without requiring additional energy. “I am repeatedly fascinated and delighted by how clever inspirations, for example from nature, are used to research compelling solutions that tackle the challenges of the future. I am delighted that we at the Gips-Schüle-Foundation can support such outstanding projects in Baden-Württemberg with our award,” says Dr. Stefan Hofmann, Chairman of the Stuttgart-based Gips-Schüle-Foundation.

The concentrated expertise of two exceptionally strong research consortia has flowed into “Solar Gate”: The Cluster of Excellence “Integrative Computational Design and Construction for Architecture (IntCDC)” at the University of Stuttgart has been conducting research since 2019 on digital technologies for future-oriented, climate-positive design and construction. The Cluster of Excellence “Living, Adaptive and Energy-autonomous Materials Systems (livMatS)” at the University of Freiburg has built up extensive expertise in the fields of materials science and biomimetics. The two clusters are connected by a long-standing collaboration in bio-inspired architecture. “Joint successes like Solar Gate highlight the high value of this special partnership,” emphasizes Prof. Peter Middendorf, Rector at the University of Stuttgart. “Solar Gate represents cutting-edge research at the highest level and proves once again that interdisciplinary networking is a driving force for visionary ideas. I warmly congratulate Achim Menges, Thomas Speck, and the entire Stuttgart and Freiburg Solar Gate team on the award from the Gips-Schüle-Foundation!"

The bio-inspired, weather-responsive, adaptive shading system “Solar Gate” could reduce CO₂ emissions from buildings by up to 30 percent. “Given that the construction sector is responsible for around 37 percent of global CO₂ emissions, Solar Gate makes an important contribution to climate protection,” says Achim Menges. 

Achim Menges and Thomas Speck drew inspiration for this innovative shading system from pinecones. They close their scales in wet conditions to protect their seeds, and open them in dry conditions to disperse the seeds. This controlled change of the cones is made possible by two layers that react differently to moisture.

Biologist Thomas Speck describes it as "a system that is highly robust and resilient, capable of functioning effectively even under significant disturbances." Together with Stuttgart architect Achim Menges, he has adapted this hygromorphic mechanism into an innovative shading system. For this purpose, the team produced modules using a 3D printer, which also feature two adjacent layers of material that swell differently and can deform in a controlled and rapid manner. These are suspended on metal wires between the panes. Humidity enters through slots in the aluminum frame, causing the modules to open or close completely on their own within a short time.

In this way, the "Solar Gate" shading system sets new standards on two fronts: it requires neither additional energy nor external control. Because the modules respond entirely autonomously to the weather. Achim Menges has turned this into a kind of blueprint for construction. Unlike with cones, what matters in “Solar Gate” is that the modules create as much shading as possible under the summer sun, while also contracting enough to allow the winter sun to shine into the building or to let in sufficient light on cloudy days.

For this purpose, the modules are 3D-printed from bio-based polyvinyl and cellulose fibers. This new additive manufacturing technology makes it possible to print the modules so that the material later curls into its programmed shape in response to environmental stimuli. Ultimately, it is a form of 4D printing, because the fourth dimension comes into play, namely, time. Computer-based manufacturing allows the responsiveness of the material to be precisely determined and optimally adapted for use in buildings. This ensures that the shading system reliably closes in hot conditions and opens in cold weather.

Following initial laboratory tests, the new shading elements were exposed to real weather conditions and tested on the Biomimetic Shell, a research building at the Freiburg Center for Interactive Materials and Bioinspired Technologies. It was observed that the shading elements responded reliably and autonomously to humidity. Despite changing weather conditions, the cellulose double layers showed no mechanical damage even after a year. In the next step, “Solar Gate” will be further developed with partners from industry.

“Solar Gate” was funded by the German Research Foundation (DFG) within the framework of the Excellence Strategy of the federal and state governments. The University of Stuttgart project participants included the Institute for Computational Design and Construction (ICD), the Institute of Polymer Technology (IKT), and the Excellence Cluster "Integrative Computational Design and Construction for Architecture" (IntCDC). At the University of Freiburg, the Plant Biomechanics Group, the Institute for Microsystems Engineering (IMTEK), and the Excellence Cluster Living, Adaptive, and Energy-autonomous Materials Systems (livMatS) were involved in the project.

The Gips-Schüle-Foundation
The Gips-Schüle-Foundation supports science for humanity and young research with visionary ideas in Baden-Württemberg. Its focus is on STEM subjects (Science, technology, engineering, and mathematics) as well as on interdisciplinary projects. The Stuttgart-based foundation works closely with universities and research institutions in Baden-Württemberg and enables the implementation of forward-looking research projects.