Solar energy is regarded as a renewable, climate-friendly and clean carrier of the energy transition. However, if the solar system has become obsolete or is defective, the question arises what happens to it. The research focus of the Austrian lead project “Sustainable Photovoltaics” is the sustainable recycling and further development of the materials of photovoltaics.
Photovoltaic modules have a life expectancy of around 25 to 30 years, sometimes longer. Currently, many first-generation systems are slowly reaching the end of their performance range. The systems consist of many components such as glass, silicon cells, silver, copper, plastic or the aluminum frame. Some ingredients such as lead or fluorine are particularly hazardous. Defective or obsolete modules are usually processed in common recycling plants in which the glass is shredded. Residues often end up in incinerators. A professional and specialized waste disposal system for optimal raw material utilization does not yet exist.
Recycling and development
In order to improve the ecological and sustainability balance of photovoltaic systems in the future, research is already being carried out in many ways. The recently launched Austrian lead project “Sustainable Photovoltaics – PVRe²” focuses on sustainable recycling, the further development as well as the repair of defective photovoltaic modules.
Project manager Gernot Oreski from PCCL: “The goal is to optimize the entire recycling process of PV modules on the one hand and to increase the recyclability of the individual solar components on the other hand. For this purpose, we want to investigate the chemical, physical and mechanical principles for a stratified separation of the individual components of a PV module. In order to enable a sorted recycling, we want to develop an automatic measuring systems that allow precise identification of the material composition of individual modules.”
Also the repair of damaged modules is incorparated in the research. Lukas Neumaier Project Manager of the Research Center CTR Carinthian Tech Research: “This is mainly about the development of suitable repair systems, which can be carried out quickly and easily at the photovoltaic plant in the field. We want to detect as soon as possible whether there are signs of wear on the back cover. In this way we can improve the choice of repair measures and ultimately extend the service life and service life of a photovoltaic module. “
Recyclable solar systems
Sustainability starts with the materials and the choice of materials. The research team intends to take this aspect into account by developing low-cost, sustainable PV modules through recycling-friendly design (such as easy-to-dissolve adhesive bonds and thermoplastic materials) as well as reducing and avoiding toxic and hazardous materials (such as lead). The use of innovative materials with high reliability, repairability and recyclability is to be accelerated by the research.
The research team can also access successful results from previous projects. By the approach “gluing instead of soldering” the lead content of about 20 grams per PV module was reduced to almost zero. The first lead-free solar plants are already in use by the city of Villach and have been awarded the Energy Globe Award 2017 in the category “Earth”. The research results on the development of climate-adapted photovoltaics are also being used. Here, the effects of climatic conditions on materials, components, cell connectors and backsheets were analyzed and improvement measures were initiated.