Researchers at the Finnish Aalto University developed a textile collection capable of generating energy via solar cells, which they turned into a jacket as proof-of-concept.

The Sun-powered Textiles project explores the possibility of using solar panels as an energy source for smart clothing “without the wearer looking like a robot”. In addition, the aim was not to attach solar cells to the surface of the textile, which would ensure maximum energy harvesting. However, it also compromises the aesthetics of the textile.

Therefore, the researchers hid the solar cells underneath a textile layer. The upper layer is purposely designed to let sunlight pass through it. The researchers measured the optical properties of 300 commercially available jackets used for professional and functional wear. They found that a variety of fabrics can be used as the cover textile, depending on the application. The fibre material, textile structure, density, colour and after-treatments all impact the optical properties of textiles.

By visibly concealing the solar cells, a broader freedom of design can be reached. At the same time, the cells still generate enough energy to power wearable devices.

Under the fabric, commercially available solar cells were inserted, which were found to be durable enough to tolerate mechanical and thermal stress during use and care. The solar cells are protected by a waterproof thermoplastic film on both sides, so clothing made of the material can be washed.

As proof of concept, the researchers created various solar cell jackets, made with different fabrics. The prototype features temperature and humidity sensors.

A jacket won’t generate enough energy to power a smartphone, but it can power sensors embedded in clothes, for instance that measure temperature or humidity.

Photos: Anne Kinnunen / Linda Lehtovirta / Emilia Pennanen / Jaakko Eskola/ Bettina Blomstedt