Designer Petra Blaisse, founder of studio Inside Outside, is no stranger to using textiles in architecture. But for years she dreamed of enabling her textiles to make use of the sun's energy instead of just blocking it. 

That process turned out to be highly complex. The TextielLab brought solar cell experts Solar Fiber to the table to help with the technical requirements for working with conductive materials. One of the hardest parts of the proces was finding the right material. Petra was assisted by product developer Sarena Huizinga. 

'From minimising stretch to making pockets and incorporating conductive copper wire in a single fabric, in this project we took knitting to the limit'. 
– Sarena Huizinga
product developer Textile Lab

Knitted fabrics always have a degree of stretch. Yet that was exactly what Petra Blaisse's solar curtain was not allowed to do. Otherwise it would sag when hung across a building's facade. And so the search was on for a non-stretch stitch. 'We eventually found a knit that only stretched in one direction but remained firm in the other', says TextielLab product developer and knitting expert Sarena Huizinga. 

This proje t was unlike any other and very technical. As it was all new terrain, it was very much a case of trial and error to find out what worked and what didn't. Conductive copper wire is a very tough materal to know with and multiple needles were lost. After lengthy testing, knitting the actual prototype was still a hands-on job, taking three hours to complete a 1 x 1 metre panel. But the result is a one-of-a-kind design.