Solar panels, hailed as a crucial tool in combating carbon emissions, face a significant challenge as they gradually degrade and become less efficient over time.

Typically, after 25 to 30 years, it becomes more cost-effective to replace them with new panels. This raises concerns about the billions of solar panels worldwide that will eventually need to be disposed of and replaced.

“The world has installed more than one terawatt of solar capacity. Ordinary solar panels have a capacity of about 400W, so if you count both rooftops and solar farms, there could be as many as 2.5 billion solar panels.,” says Dr Rong Deng, an expert in solar panel recycling at the University of New South Wales in Australia.

Unfortunately, the specialised infrastructure for scrapping and recycling these panels is currently lacking, prompting energy experts to call for urgent government action to prevent a looming global environmental disaster.

However, there is hope on the horizon. At the end of June, the world’s first factory dedicated to fully recycling solar panels officially opened its doors in France. Owned by ROSI, a specialist solar recycling company, the facility located in the Alpine city of Grenoble aims to extract and re-use 99% of a panel’s components. This includes not only recycling the glass fronts and aluminium frames but also recovering precious materials such as silver and copper, which are notoriously difficult to extract. These rare materials can then be recycled and utilised to manufacture new, more powerful solar units.

While conventional methods of recycling solar panels manage to recover most of the aluminium and glass, ROSI points out that the quality of the glass obtained through these methods is relatively low. It can be repurposed for applications like tile production, sandblasting, or mixing with other materials to create asphalt. However, it falls short for applications that require high-grade glass, such as the production of new solar panels.

The new ROSI plant aims to overcome this limitation, providing a solution that can efficiently recycle solar panels while preserving the quality of materials for future use.

The opening of the ROSI plant coincides with a surge in solar panel installations worldwide. In 2021, the world’s solar energy generation capacity grew by 22%. In the UK alone, approximately 13,000 photovoltaic solar panels are installed each month, predominantly on private house roofs.

However, due to the rapid advancements in solar panel technology, many panels become relatively uneconomical before reaching their expected lifespan. Consequently, it often proves more cost-effective to replace panels that are only 10 to 15 years old with newer, more efficient designs. If current growth trends persist, the volume of discarded solar panels could become staggering, comparable to the 400 million tonnes of plastic produced annually worldwide.

The scarcity of solar panel recycling facilities can be attributed to the recent emergence of significant waste volumes. The first generation of domestic solar panels is now reaching the end of its usable life, necessitating urgent action to tackle the impending waste challenge.

“Now is the time to think about this,” says Ms Collier.

France stands out as a leader in Europe regarding photovoltaic waste processing. Organisations like Soren, in partnership with ROSI and other companies, coordinate the decommissioning of solar panels throughout the country. ROSI’s high-tech plant in Grenoble employs meticulous disassembly techniques to recover precious materials such as copper, silicon, and silver from solar panels.

“The biggest one [we decommissioned] took three months,” Mr Defrenne recalls.

Extracting these precious materials from solar panels has been economically unviable until now due to their small quantities and intricate integration with other components. However, the value of these materials makes their efficient extraction a potential game-changer.

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

Soren’s team envisions a future where almost three-quarters of the materials required to manufacture new solar panels, including silver, can be recovered from retired panels and recycled, expediting the production of new panels.

Mr Defrenne: “You can see where you have a production bottleneck, it’s silver.”

British scientists at the University of Leicester have been researching similar technologies to extract silver from photovoltaic units using saline solutions. However, ROSI remains the sole company in its field to have scaled up its recycling operation to an industrial level.

Despite the promising prospects of intensive solar panel recycling, the technology remains expensive. In Europe, importers or producers of solar panels must responsibly dispose of them, but many opt for cost-effective methods such as crushing or shredding the waste.

Nicolas Defrenne from Soren acknowledges that solar panel recycling is still in its early stages.

Last year, Soren and its partners recycled just under 4,000 tonnes of French solar panels, indicating significant untapped potential. Defrenne is committed to expanding the recycling efforts to realise a substantial impact on the industry.