In Switzerland, solar furnaces to recycle metals in watchmaking

The Jura region is home to numerous watchmaking and medical instrument manufacturers that use high-quality steel. The goal is to recover their production waste and remelt it into ingots using concentrated solar energy, thereby resupplying companies on both sides of the French-Swiss border via a short supply chain.

"I've been dreaming of this moment for 10 years," Raphaël Broye, CEO of Panatère, an SME specializing in the processing and recycling of metal raw materials, told the press.

La Chaux-de-Fonds is known as the cradle of Swiss watchmaking, where Panatère will continue to conduct tests with local companies before opening a factory in 2028, either on site or in the Valais mountains.

The company hopes to be able to produce 1.000 tonnes of recycled steel there each year using solar energy, which would be unprecedented on this scale - thanks to furnaces where the temperature can approach 2.000 degrees Celsius.

This site, inaugurated on Friday, is therefore "only a step," explained Mr. Broye, who intends to demonstrate, however, that this solar technology is not just "a concept" but a process that can be used in industry.

Some 148 scientists and professionals worked on the first prototype, consisting of a heliostat covered with movable mirrors measuring 140 square meters and a 10-meter diameter dish that focuses the rays onto a crucible where the metals are melted.

To design these prototypes, the company had to learn to manage the winds that move the mirrors, the sand dust from the Sahara that sometimes reaches the Swiss mountains and obstructs the panels, and even the temperatures that can drop to -20 degrees in winter and exceed 30 degrees in summer.

"Today, there's a real economic model to develop," Mr. Broye also emphasizes. "With the price levels and the scarcity of metals, we're able to find a position to make these projects profitable," "even with Swiss salaries," he explains, handling copper shavings whose prices are skyrocketing.

"This restores the nobility of short supply chains," he believes, with these high prices leading watchmakers and manufacturers to realize that they have "a treasure at the back of their factory" with their production waste.