In autumn 2022, Stoelzle participated in an innovation pitch, which was organised by the Austrian Chamber of Commerce. As an energy-intensive industrial company it is always seeking innovative ideas in which to help reduce consumption in all production processes, as well as increasing the use of green energy. As the glass manufacturer already gains green energy the next step was finding a way to store any excess.

Stoelzle is taking a closer look at Polar Night Energy; a small start-up company from Finland, founded by Markku Ylönen and Tommi Eronen. The company has developed a patented sand-based thermal energy storage system. “As a material, sand is durable and inexpensive and can store a lot of heat in a small volume at a temperature of about 500–600°C,” explains Mr Ylönen. It has been successfully trialled in the town of Kankaanpää, Finland.

Niklas Zwettler, Head of R&D at Stoelzle Glass Group, is leading this project and looking to extend the process: “Glass production is a very energy intensive process. We have set ourselves the target to halve our CO2 emissions by 2030 and become carbon-neutral by 2050. So far, Polar Night Energy has discovered a way of extracting heat to warm water and feed local heating systems. Now, we need to discover how to retrieve electricity from the energy that is stored in the sand, in order to have a reliable source of green electricity to fire our furnaces. We’re excited to see how this system will work for us.”

www.stoelzle.com