Near Bordeaux, the challenge of recycling solar panels

Sheltered under a small corrugated metal shed in Saint-Loubès, a “unique in the world” prototype, designed in Japan, cuts a used panel every two minutes.

With its blades heated to 300°C, this "delaminator" about twenty meters long separates -- like "the layers of a millefeuille" -- the aluminum frame, the glass plate, then the very thin photovoltaic cell . At the end of the line, an employee scrapes the rectangle of glass obtained with a scraper to remove the last impurities.

The plates thus cleaned are reused by "a great French glassmaker" to transform it into flat glass in the form of windows, verandas or even perfume bottles, explains Frédéric Seguin, manager of this site founded last year -- when the usual method of "grinding" sent the pieces of glass directly to the "road underlay".

“Glass is 70% of the solar panel and what interests me first is the impact on the planet”, explains, proud of its “95% recycling rate”, this director of the he local branch of Envie 2E, a network of integration companies specializing in the treatment of household waste.

Critical metals

Because with the French objective of multiplying solar energy production capacities tenfold by 2050, waste from photovoltaic panels, with a lifespan of 20 to 30 years, will multiply.

According to Nicolas Defrenne, director of Soren, the eco-organization responsible for recycling the sector, the quantity of waste to be treated should increase from 3.800 tonnes in 2022 to "300.000 tonnes from 2030" with, ultimately, nearly ten of reprocessing centers compared to three currently.

For him, the interest of the process of this "showcase" factory remains the possibility of recovering, "with great purity", the "critical metals" with "high added value" (silver, copper and silicon) embedded in the circuits.

Cut into thin strips, the rolls of photovoltaic cells obtained are sent to RosiSolar, a Grenoble start-up, which separates these precious metals from each other via thermal and chemical treatment.

The metals collected, reusable in the electric automobile industry or the production of semiconductors, will be used for “the creation of sovereign production sectors in Europe”, we bet at RosiSolar.

“Money is 0,08% of a solar panel but 20% of its value,” explains Mr. Defrenne, who sees recycling as an “indispensable” tool to “guarantee the supply” of resources and “succeeding in the energy transition”.

According to the International Energy Agency, reuse could ultimately represent more than 60% of the silver present in solar panels, while global reserves of silver mines are insufficient to cover all of the needs of the photovoltaic industry.

Reuse

The solar panel recycling market could be worth nearly $80 billion in 2050, according to a study by Rystad Energy.

But in an industry which tends to "throw away" old panels, which have become less profitable with technological progress, we must first "get used to extending their lifespan", considers Christophe Joussot-Dubien, circular economy manager for low-carbon energies at the CEA (Atomic Energy and Alternative Energies Commission).

In Gironde, the Envie 2 E site also offers the resale, after a battery of tests, of used panels. But this first on an industrial scale is temporarily frozen, the time to structure the sector to convince, downstream, installers and insurers.

In Saint-Loubès, the town hall, which launched several sustainable renovation and energy saving projects, failed to have second-hand panels from the factory installed by building professionals, due to a problem of "technical compliance ", regrets councilor Emmanuelle Favre.

Reuse is “a recent culture for everyone” and “spontaneously, we will always bring you something new…” laments the elected official in front of the panels, freshly imported, which were installed on the playground of a school. the municipality.