Wooden solar trackers

In the framework of this project, solar panels will be installed on the roof of the ETH House of Natural Resources with an innovative tracking system. The solar panel will track the sun by reversibly actuated wooden bilayers.

Wood swells and shrinks when the ambient relative humidity is altered. Using the bilayer principle by gluing together two wooden layers with perpendicular fibre orientation the swelling and shrinking is transformed into bending.

Whereas relative humidity is very high in the morning at sunrise, it decreases during the day, usually reaching its minimum in the late afternoon and increases again during the night. Powered by this daily pattern, wooden bilayers can be used as motors to drive the movement of solar panels at the ETH House of Natural Resources. In this way, a solar driven, autonomous and very much simplified tracking system is implemented and tested.

Further information can be found on the homepage of the institute for building materials.