translucent solar panels of off-grid electric lighting installation
Main Light by ttal is self-contained lighting installation developed along the bank of the main river in Frankfurt, Germanyfrom Munich-based studio ttal in collaboration with the Italian lighting manufacturer ewo. Presented as part of the World Design Capital 2026 initiative, the project explores how renewable energy infrastructure can become an integrated and visible element of public space through autonomous solar-electrical lighting systems.
The installation introduces a new generation of off-grid street lights that generate renewable energy directly at the point of use through translucent organic photovoltaic (OPV) solar panels. Developed in response to the increasing energy demands of urban areas, light pollution and the environmental impact of conventional public lighting systems, the project rethinks road infrastructure through the concept of “consumers”, systems that consume and produce energy.
Unlike traditional urban lighting, which depends on underground electrical networks and extensive site intervention, Main Light operates through lightweight self-contained structures that do not require wiring or permanent ground excavation. The modular system allows for flexible installation with reduced material usage, while supporting lighting solutions for both urban environments and underserved public spaces.
The Main Light rises alongside the River Main, transforming the skyline of Frankfurt | all images courtesy of ttal
colored solar panels cast changing light on the river bank
The project also examines the ecological effects of artificial lighting on humans, plants and nocturnal ecosystems. The lighting systems are designed using full cutout technology, intelligent demand-based controls and a warm-spectrum light source intended to reduce ecological disturbance while maintaining visibility and orientation within the public space.
During the day, the translucent solar surfaces act as visible energy generation elements in the urban landscape. Their colored panels cast shifting shadows and filter light patterns on the riverbank, creating shaded gathering areas and reinforcing the installation’s presence as an urban spatial arrangement rather than a hidden infrastructure. At night, the structures emit controlled low-impact lighting that balances public accessibility with environmental sensitivity. Through this dual role as both energy producer and lighting system, Main Light positions renewable energy as an active architectural and public element in the urban environment.
The first pilot installation from ttal’s designers Tobias Trübenbacher and Andreas Lang are transforming a section of Frankfurt’s riverside into a testing ground for autonomous public infrastructure combining renewable energy generation, lighting design and spatial activation. The project was implemented in collaboration with ewo GmbH for lighting and control technology, ASCA GmbH & Co. KG for organic photovoltaic systems, Schake GmbH for steel structures and reversible concrete foundations and merz kley partner GmbH for structural engineering.
Main Light works off-grid on reversible bases that double as urban furniture
Studio ttal refined the form and proportions of the installation through a series of life-scale models
