In the heart of Switzerland’s watchmaking country, a novel industrial solution is harnessing the power of the sun to forge a new path for sustainable manufacturing. A Swiss company has unveiled the world’s first industrial solar furnaces specifically designed to recycle high-value steel and other metal offcuts from the region’s prestigious watchmaking and medical device industries. This initiative, inaugurated in early October 2025 in the city of La Chaux-de-Fonds, uses concentrated sunlight to melt scrap metal into high-quality ingots, creating “green steel” with a minimal carbon footprint.
The project represents a significant leap forward in creating a localized circular economy, transforming industrial waste into a valuable resource directly at its source. By processing tonnes of metal shavings that were previously shipped abroad for lower-grade recycling, the company is tackling what its founder called an “ecological and economic aberration.” This new venture not only drastically reduces the environmental impact associated with traditional metallurgy but also strengthens regional supply chains, boosts resource independence, and positions Swiss high-precision manufacturing at the vanguard of the global green transition.
The Technology of Concentrated Sunlight
The innovation lies in its direct and powerful application of solar thermal energy. The system, developed by the Swiss firm Panatere, does not use solar panels to generate electricity but instead functions like a massive magnifying glass. The facility features a 140-square-meter field of movable mirrors, known as a heliostat, which tracks the sun’s movement throughout the day. These mirrors reflect and beam sunlight towards a large, 10-meter-diameter dish that acts as a concentrator.
This dish focuses the thousands of sunbeams onto a single, precise point: a crucible containing the metal waste. The intense concentration of energy generates immense heat, allowing the furnace to reach temperatures approaching 2,000 degrees Celsius. This is more than sufficient to melt high-grade stainless steel, titanium, and other alloys used in precision manufacturing, purifying them into reusable ingots. The development of the prototype was a significant undertaking, involving the expertise of 148 scientists and professionals who worked to overcome numerous environmental challenges. Engineers had to devise systems to cope with wind interference on the mirrors, the occasional arrival of Saharan dust that can coat the reflective surfaces, and the region’s extreme temperature swings, from -20C in the winter to over 30C in the summer.
A New Frontier for Urban Mining
The project is situated in the Jura mountains, the cradle of Swiss watchmaking and a hub for medical instrument manufacturing. These industries inherently produce a significant amount of high-quality metal waste in the form of shavings and offcuts. Annually, the Swiss watchmaking industry generates an estimated 1,500 tonnes of steel shavings alone. Panatere’s CEO, Raphaël Broye, noted that with soaring metal prices and increasing scarcity, manufacturers are realizing they have “a treasure trove round the back of their factories.” This initiative provides the tool to unlock that local treasure.
Previously, this valuable scrap was often sold and shipped internationally for reprocessing, a system that incurred significant transport-related emissions and resulted in the material being downcycled into lower-quality products. The solar furnace facility establishes a closed-loop system entirely within the region. It collects waste from local watchmaking, medical, and even aeronautical companies and transforms it back into pristine ingots that can be sold directly back to those same industries. This model of hyper-local industrial recycling strengthens the regional economy, reduces dependence on volatile global supply chains, and provides manufacturers with a verifiable source of green metal.
A Decade-Long Vision Realized
The launch of the furnaces is the culmination of a long-term vision for Panatere and its founder. The journey began over a decade ago, with CEO Raphaël Broye stating he had been dreaming of this moment for 10 years. The company itself was founded in 2012, and the specific idea for using solar power for recycling was conceived around 2015. This long-term commitment highlights the persistence required to bring disruptive industrial technologies from concept to reality.
A critical milestone occurred in December 2021, when the company successfully melted its first ingot using solar energy at an established research furnace in Odeillo, France, proving the viability of the process. Following that success, the company focused on building its own industrial-scale demonstrator in Switzerland. The entire technological process, from the sorting of metal alloys to the specific design of the solar furnace, is now protected by two patents. The inauguration in October 2025 serves as a proof of concept, demonstrating that solar metallurgy is not just a theoretical concept but a workable and scalable industrial process.
Scaling Up for a Sustainable Future
With the successful launch of the demonstration site, Panatere is looking toward significant expansion. The current facility in La Chaux-de-Fonds is considered an initial step. The company will continue to conduct tests and collaborate with local companies to refine its processes. The next major goal is to open a full-scale factory by 2028, which may be built on the current site or in the Wallis mountains in southwestern Switzerland.
The ambition is to achieve an annual production capacity of 1,000 tonnes of solar-recycled steel by that time. This would allow the facility to process a substantial portion of the region’s industrial metal waste. According to Broye, a viable economic model is now firmly in place. The combination of high global metal prices and material scarcity makes the project profitable, even with the high operational and labor costs associated with Switzerland. This economic sustainability is crucial for the long-term success and potential replication of the technology in other high-value manufacturing hubs around the world, heralding a new, cleaner chapter for industrial production.