Intensive recycling of solar panels is still in its infancy

Meanwhile British scientists have been trying to develop similar technology to ROSI.

Last year, researchers at the University of Leicester announced they had worked out how to extract silver from PV units using a form of saline.

But so far, ROSI is the only company in its field to have scaled up its operation to industrial levels.

Moreover, the technology is expensive. In Europe, importers or producers of solar panels most dispose of them responsibly. And many favour crushing or shredding the waste - which is far cheaper.

Mr Defrenne acknowledges that intensive recycling of solar panels is still in its infancy. Soren and its partners recycled just under 4,000 tonnes of French solar panels last year.

But there is potential to do a lot more. And he's making that his mission.

"The weight of all the new solar panels sold last year in France was 232,000 tonnes - so, by the time those wear out in 20 years, that's how much I'll need to collect every year.

"When that happens, my personal goal is to ensure France will be the technological leader of the world."