Closing the Loop on Solar: A Sustainability Assessment of Photovoltaic Recycling in Greece
Abstract
1. Introduction
2. Methodology
- Identification of annual installed capacity: The total PV capacity installed each year in Greece was collected from CRES records and verified with data from national and European statistical sources.
- Determination of the average panel power per year: For each year, the typical power rating of the most widely used PV modules was identified to reflect prevailing market technologies and efficiency levels. The annual values of average panel power were obtained directly from the CRES database, which documents the PV modules most commonly installed in Greece each year, and were cross-checked using manufacturer datasheets. This approach ensures that the selected values represent actual market conditions and the dominant technologies used during 2009–2023.
- Estimation of the number of panels installed annually: The annual installed capacity (MW) was divided by the average power output per module (kW) to calculate the number of panels installed each year.
- Establishment of the weight-to-power ratio: The ratio of panel weight to power rating (kg/kW) was determined for each year to represent technological evolution and improvements in design efficiency. These ratios were derived using CRES market data and corresponding datasheets of the most widely deployed panels each year, ensuring consistency with real-world module characteristics.
- Calculation of the total mass of PV panels installed annually: The number of panels was multiplied by the average panel weight to estimate the total mass of PV panels (in tons) installed each year in Greece.
- Determination of raw-material composition: Based on the typical composition of crystalline-silicon PV modules, approximately 76% glass, 10% plastic (mainly EVA), 8% aluminum, 5% silicon, and 1% other metals (silver, copper, tin, etc.), the corresponding mass fraction of each material per ton of PV waste was calculated. The composition percentages of silver, copper, and tin were based on published characterizations of crystalline-silicon modules [3,6,10], which consistently report small but significant fractions of these metals in PV panels.
- Estimation of recoverable materials: Recognized recovery efficiencies were applied to each material: aluminum (100%), glass (95%), silicon (85%), copper (97%), silver (98–100%), and tin (32%). The annual quantities of recoverable materials were obtained by multiplying these recovery factors by the material content of the installed panels.
3. Results
4. Discussion
4.1. Environmental and Technological Implications
4.2. Policy and Economic Perspectives
4.3. Social and Health Dimensions
4.4. Toward a Circular-Economy Framework
4.5. Future Outlook
5. Conclusions
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
Abbreviations
| a-Si | Amorphous Silicon |
| BES | Bioelectrochemical Systems |
| CdTe | Cadmium Telluride |
| CIGS | Copper Indium Gallium Selenide |
| CRES | Center for Renewable Energy Sources |
| EoL | End of Life |
| EU | European Union |
| EVA | Ethylene-Vinyl Acetate |
| GHG | Greenhouse Gas |
| IEA | International Energy Agency |
| IRENA | International Renewable Energy Agency |
| LCA | Life Cycle Assessment |
| MFC | Microbial Fuel Cell |
| Mono-Si | Monocrystalline |
| NECP | National energy and climate plan |
| Poly-Si | polycrystalline (Poly-Si); |
| PV | Photovoltaic |
| RES | Renewable energy sources |
| SSTD | Solvothermal Swelling with Thermal Decomposition |
| TCLP | Toxicity Characteristic Leaching Procedure |
| WEEE | Waste from Electrical and Electronic Equipment |
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| Recycled Material | Value (USD/t) |
|---|---|
| Silicon | 2000 |
| Aluminum | 661.39 |
| Silver | 551,156.11 |
| Glass | 10 |
| Copper | 6702.06 |
| Tin | 132.28 |
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Kiskira, K.; Lalopoulou, A.; Kalkanis, K.; Vokas, G. Closing the Loop on Solar: A Sustainability Assessment of Photovoltaic Recycling in Greece. Energies 2025, 18, 6314. https://doi.org/10.3390/en18236314
Kiskira K, Lalopoulou A, Kalkanis K, Vokas G. Closing the Loop on Solar: A Sustainability Assessment of Photovoltaic Recycling in Greece. Energies. 2025; 18(23):6314. https://doi.org/10.3390/en18236314
Chicago/Turabian StyleKiskira, Kyriaki, Angeliki Lalopoulou, Konstantinos Kalkanis, and George Vokas. 2025. "Closing the Loop on Solar: A Sustainability Assessment of Photovoltaic Recycling in Greece" Energies 18, no. 23: 6314. https://doi.org/10.3390/en18236314
APA StyleKiskira, K., Lalopoulou, A., Kalkanis, K., & Vokas, G. (2025). Closing the Loop on Solar: A Sustainability Assessment of Photovoltaic Recycling in Greece. Energies, 18(23), 6314. https://doi.org/10.3390/en18236314

