In the near future it will be possible to produce solar modules that can be completely recycled, which will improve our CO2 footprint tremendously. TNO collaborated with three innovative Dutch companies to develop a solar panel that will last about thirty years, after which its components can be reused. This resolves a major disadvantage of current solar panels, which end up in the shredder at the end of their lifespan.
Since recently, the attention for recycling solar panels at the end of their functional life is growing rapidly. Research efforts are aimed at recovering economically valuable materials such as metals, high grade silicon and glass. Improvements of the currently applied recycling methods are urgently needed, where the focus should shift towards solving the problems at the source. The scientific and technical challenge is to re-design the solar panel, such that all components can be fully recovered in an easy manner.
TNO collaborated with three innovative Dutch companies to develop a solar panel technology enabling ‘Design for Recycling’ (D4R) without compromising the panel lifetime. A D4R approach can exchange the present rudimentary and detrimental panel shredding technique by sophisticated dismantling. Key technology of the D4R approach is a novel encapsulant (adhesive foil essential to embed the solar cells into a PV panel) with an integrated trigger mechanism for material separation at end of life. The mechanism functions with low energy usage and is non-toxic allowing harvesting of valuable materials in a non-destructive way and free of encapsulant residues.
In the TKI project DEREC (Design for RECycling) a proof of principle for easy dismantling was demonstrated on functional small scale test panels consisting of 4 solar cells. These test panels were subjected to extended fatigue tests indicating a simulated 30 year live span of panel outdoor operation. At the simulated end of life the trigger mechanism of the encapsulant was successfully activated, uncovering the solar cells. Based on the promising results a follow up project has been granted for scaling up the technology towards full size D4R panels (PARSEC project).
Within the new PARSEC project the partners aim for realizing industrial production and integration into standard manufacturing processes for full size solar panels. The fabrication of both the materials and the circular solar panels needs to be scaled up in order to produce at competitive costs and create a significant market share. Partners in the PARSEC project are DSM Advanced solar solutions, Mat-Tech, Exasun, and TNO Energy Transition, solar energy division Petten. ABN-Amro provides the outdoor test location at the CIRCL Building in Amsterdam.
TNO aims for a two pronged approach. On the long term D4R panels can add significantly to an optimized recycling at end of life. However more urgent are technologies to recycle currently applied PV panels. TNO investigates and develops novel recycling techniques for solar cells and the glass material. The aim is to harvest high grade silicon in a purity to be reused for solar cells and other silicon based products such as thermo-elements and for car batteries. A novel technology enables to process the recycled glass material into new solar panel material.
High value recycling supports a circular production and presents a clear solution to solar panel end of life waste. In the EU alone, some 4,000 tonnes of solar panels are destroyed every year using environmentally detrimental methods. In a recent report, the International Renewable Energy Agency estimated that globally at least 60 million tonnes of solar panels will have reached the end of their lifespan by 2050. In addition, producing of D4R panels closer to home means this product has an environmental advantage because of the much shorter transport distances.