The Keep It Wool project of the Summit Foundation from Vevey in the Swiss canton of Vaud and the University of Lausanne (UNIL) is investigating whether Swiss lamb’s wool can replace the polyester or polypropylene geotextiles currently used on glaciers. According to a statement, geotextiles are used to slow the melting of specific glacier areas during the summer. These covers partially reflect solar radiation and limit heat exchange. However, fibers from the geotextiles can gradually be detached due to wind and wear, before being washed downstream into the water cycle by glacial meltwater.
According to Laurent Thurnheer, director and founder of the Summit Foundation, wool represents a particularly interesting candidate as an alternative to these synthetic covers. “It is a local, natural resource that is currently largely undervalued”, he explains in the statement, “and we may be able to give it a new use while reducing reliance on synthetic materials”.
Wool offers significant advantages in that it is natural, renewable, biodegradable and insulating. Moreover, it offers largely untapped market potential in Switzerland, as sheep tend to be raised for meat, milk or landscape maintenance, while the wool itself is regarded as a low-value by-product. According to estimates, up to 70 percent of the wool produced today ends up either incinerated or composted.
On June 22, two prototypes of varying densities and a surface area of 100 square meters were installed at Glacier 3000 in the canton of Vaud. The lamb’s wool prototypes were manufactured by Fisolan AG from Worb in the canton of Bern, a company that has been processing Swiss lamb’s wool as insulation for buildings since 2012. A conventional geotextile cover was used for comparison. Since then, measurements have been taken every fortnight in order to assess the durability of the material and its ability to limit melting. According to the Summit Foundation, initial observations indicate that the wool and the geotextile perform very similarly.
The project, launched in 2025 in partnership with the UNIL’s Interdisciplinary Centre for Mountain Research (CIRM), is being carried out by four UNIL Master’s students in cooperation with the Filature de l'Avançon Association, Fisolan AG and researchers from the Swiss glacier monitoring network GLAMOS as well as with the support of Innosuisse, the Swiss Innovation Agency. ce/aj