In previous studies, solar cells have been installed on the surfaces, layered on top, or weaved into the threads of textiles. During the 3-year Sun-powered Textiles project, researchers at Aalto University’s departments of physics and design developed a method of adhering solar cells to textiles in a way that makes them resistant to machine-washing and recyclable. The machine-washability of commercially available solar cells had not been studied previously to this extent.
The researchers laminated a solar cell component between textiles in a water-tight polyurethane film to make the component machine-washable. The textiles containing the solar cell component were then washed dozens of times at 40 °C. The output of the solar cells after each round in the washing machine was then measured. 5 of the 8 samples retained their efficiency, and 3 lost about 20% of their power. None of the cells or the textiles were damaged during the process.
Key factors in the ability of textiles to let light through them include the material, transparency and crosscut of the fiber, structure of the threads, thickness and weave of the fabric, colors and the finish.
Researchers at Aalto University, Aalto/Finland, used materials that were made of only a single fiber and could be recycled as efficiently as possible. Electronic components can be removed from the fabric simply by first applying heat and then tearing them off. The amount of energy the cells receive depends on their size, quantity and location. The amount of energy that is needed is mandated by what the use-application is. The solar cells hidden in textiles are suitable for things like measuring temperature and humidity. Promising applications include work and outdoor clothing, and curtains which react to changes in the amount of light.