Since the beginning of the 2000s, national and EU research projects have been underway to develop the basic recycling processes of solar modules for the various PV technologies. In this context, the ZSW has been able to demonstrate the basic feasibility of recycling CIGS thin-film PV modules.
One feature that all PV technologies have in common is that their largest component by weight is glass, and that a very strong bond between the glass and polymers is formed in order to guarantee a service life of more than 30 years. This very strong bond is extremely difficult to break down, however, and is therefore the greatest challenge for an economic recycling of end-of-life solar modules.
Today, only the components aluminium frame, cables and the junction box, and the glass are recovered. The other metallic materials, manufactured in processes consuming large quantities of energy and resources, are lost since none of the processing methods developed in research projects to date have proven to be economically viable. Since recycling quotas are stipulated by law, a levy paid by the manufacturers and importers of solar modules supports the cost of recycling solar modules in Germany and Europe.
Germany was a pioneer in the installation of solar modules and was the largest single market until 2015. This means that relatively large and therefore commercially valuable quantities of end-of-life solar modules are expected to be available for recycling in Germany in the coming years. A long-term recycling infrastructure is thus becoming significantly more relevant.
In the project "RePotPV ", currently funded by the Federal Ministry for Economic Affairs and Energy (Bundeswirtschaftsministerium – BMWi), the partners Fraunhofer IBP and ZSW are investigating the contribution of end-of-life of PV systems to the environmental balance of PV power generation. They are evaluating current and future recycling processes which demonstrate the potential for commercial implementation in Germany. In particular, the main challenges and obstacles for a timely establishment of suitable recycling systems will be identified and the ecological-technical dependencies will be shown.