Solar panels are delaminated in order to recover precious materials

At ROSI's high-tech plant in Grenoble, the solar panels are painstakingly taken apart to recover the precious materials inside - such as copper, silicon and silver.

Each solar panel contains only tiny fragments of these precious materials and those fragments are so intertwined with other components that, until now, it has not been economically viable to separate them.

But because they are so valuable, extracting those precious materials efficiently could be a game-changer, says Mr Defrenne.

"Over 60% of the value is contained in 3% of the weight of the solar panels," he says.

The team at Soren are hopeful that, in the future, nearly three-quarters of the materials needed to make new solar panels - including silver - can be recovered from retired PV units and recycled - to help speed up production of new panels.

Currently there is not enough silver available to build the millions of solar panels which will be required in the the transition from fossil fuels, says Mr Defrenne: "You can see where you have a production bottleneck, it's silver."