Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Research and development priorities for silicon photovoltaic module recycling to support a circular economy

This article has been updated


Large-scale deployment of photovoltaic (PV) modules has considerably increased in recent decades. Given an estimated lifetime of 30 years, the challenge of how to handle large volumes of end-of-life PV modules is starting to emerge. In this Perspective, we assess the global status of practice and knowledge for end-of-life management for crystalline silicon PV modules. We focus in particular on module recycling, a key aspect in the circular economy of photovoltaic panels. We recommend research and development to reduce recycling costs and environmental impacts compared to disposal while maximizing material recovery. We suggest that the recovery of high-value silicon is more advantageous than the recovery of intact silicon wafers. This approach requires the identification of contaminants and the design of purification processes for recovered silicon. The environmental and economic impacts of recycling practices should be explored with techno–economic analyses and life-cycle assessments to optimize solutions and minimize trade-offs. As photovoltaic technology advances rapidly, it is important for the recycling industry to plan adaptable recycling infrastructure.

This is a preview of subscription content, access via your institution

Relevant articles

Open Access articles citing this article.

Access options

Rent or buy this article

Prices vary by article type



Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Projected cumulative mass of PV modules in service and decommissioned.
Fig. 2: Potential points of insertion of recovered silicon into existing silicon production processes.

Change history

  • 22 July 2020

    The Supplementary Data file for this Perspective was missing; it has now been added.


  1. Trends in Photovoltaic Applications 2019 (International Energy Agency Photovoltaics Power Systems Technology Collaboration Programme, 2019).

  2. Photovoltaics Report (Fraunhofer ISE, 2018).

  3. Hsu, D. et al. Life cycle greenhouse gas emissions from crystalline silicon photovoltaic electricity generation: Systematic review and harmonization. J. Ind. Ecol. 16, S122–S135 (2012).

    Article  Google Scholar 

  4. National Solar Jobs Census 2019 (The Solar Foundation, 2020).

  5. End-of-Life Management: Solar Photovoltaic Panels IEA-PVPS Task 12, Report #T12–06:2016 (International Renewable Energy Agency, International Energy Agency Photovoltaics Power Systems Technology Collaboration Programm, 2016).

  6. Baldé, C. P., Forti, V., Gray, V., Kuehr, R. & Stegmann, P. The Global E-waste Monitor – 2017 (United Nations University, International Telecommunication Union, International Solid Waste Association, 2018).

  7. Mahmoudi, S., Huda, N. & Behnia, M. Photovoltaic waste assessment: Forecasting and screening of emerging waste in Australia. Resour. Conserv. Recycl. 146, 192–205 (2019).

    Article  Google Scholar 

  8. Domínguez, A. & Geyer, R. Photovoltaic waste assessment of major photovoltaic installations in the United States of America. Renew. Energy (2018).

    Article  Google Scholar 

  9. Santos, J. D. & Alonso-García, M. C. Projection of the photovoltaic waste in Spain until 2050. J. Clean. Prod. 196, 1613–1628 (2018).

    Article  Google Scholar 

  10. Paiano, A. Photovoltaic waste assessment in Italy. Renew. Sustain. Energy Rev. 41, 99–112 (2015).

    Google Scholar 

  11. Wade, A., Sinha, P., Drozdiak, K. & Brutsch, E. Beyond waste – the fate of end-of-life photovoltaic panels from large scale PV installations in the EU - the socio-economic benefits of high value recycling compared to reuse. In Proc. 33rd European Photovoltaic Solar Energy Conference Amsterdam 1507–1514 (WIP Wirtschaft und Infrastruktur GmbH & Co Planungs-KG, 2017).

  12. Huang, B. et al. Environmental influence assessment of China’s multi-crystalline silicon (multi-Si) photovoltaic modules considering recycling process. Sol. Energy 143, 132–141 (2017).

    Article  Google Scholar 

  13. Müller, A., Wambach, K. & Alsema, E. Life cycle analysis of solar module recycling process. In Proc. 20th European Photovoltaic Solar Energy Conference 3211–3213 (WIP Wirtschaft und Infrastruktur GmbH & Co Planungs-KG, 2005).

  14. Lunardi, M., Alvarez-Gaitan, J., Bilbao, J. & Corkish, R. Comparative life cycle assessment of end-of-life silicon solar photovoltaic modules. Appl. Sci. 8, 1396 (2018).

    Article  Google Scholar 

  15. Stolz, P., Frischknecht, R., Wambach, K., Sinha, P. & Heath, G. Life Cycle Assessment of Current Photovoltaic Module Recycling IEA PVPS Task 12 Report #T12–T13:2018 (International Energy Agency Photovoltaic Power Systems Programme, 2018).

  16. Directive 2012/19/EU of the European Parliament and of the Council of 4 July 2012 on Waste Electrical and Electronic Equipment (WEEE) (recast) (European Commission, 2012).

  17. EN50625-2-4:2017, Collection, logistics & treatment requirements for WEEE - Part 2–4: Treatment requirements for photovoltaic panels. CENELEC,FSP_PROJECT,FSP_LANG_ID:1258637,59265,25 (2017).

  18. Photovoltaic module stewardship and takeback program. RCW 70.355.010. Washington State Legislature (2020).

  19. Preparation of a Recycling Scheme for Future Waste such as PV Panel (in Korean) (Korean Ministry of Environment (2018);

  20. Dudley, M. Victorian e-Waste Materials Flow Analysis: PV Panels and Systems - Part 3 Report (Sustainability Victoria, Randell Environmental Consulting, 2017).

  21. Concept Note/Blue Print on Management of Antimony Containing Glass from End-of-Life of the Solar PV Panels (Ministry of New and Renewable Energy, 2019);

  22. Guidelines for Promoting Recycling of Solar Power Generation Equipment 2nd edn (Japanese Ministry of the Environment, 2018);

  23. Wambach, K., Heath, G. & Libby, C. Life Cycle Inventory of Current Photovoltaic Module Recycling Processes in Europe IEA-PVPS Task 12 Report #T12–T12:2017 (International Energy Agency Photovoltaic Power Systems Programme, 2017).

  24. Solar PV Module End of Life: Options and Knowledge Gaps for Utility-Scale Plants (Electric Power Research Institute, 2018).

  25. Komoto, K. et al. End-of-Life Management of Photovoltaic Panels: Trends in PV Module Recycling Technologies IEA PVPS Task 12 Report #T12–10:2018 (International Energy Agency Photovoltaic Power Systems Programme, 2018).

  26. Deng, R., Chang, N. L., Ouyang, Z. & Chong, C. M. A techno-economic review of silicon photovoltaic module recycling. Renew. Sustain. Energy Rev. 109, 532–550 (2019).

    Article  Google Scholar 

  27. Tsanakas, J. A. et al. Towards a circular supply chain for PV modules: Review of today’s challenges in PV recycling, refurbishment and re-certification. Prog. Photovolt. Res. Appl. 28, 454–464 (2019).

    Article  Google Scholar 

  28. Latunussa, C., Mancini, L., Blengini, G., Ardente, F. & Pennington, D. Analysis of Material Recovery from Silicon Photovoltaic Panels EUR 27797 (Publications Office of the European Union, 2016).

  29. Latunussa, C., Ardente, F., Blengini, G. & Mancini, L. Life cycle assessment of an innovative recycling process for crystalline silicon photovoltaic panels. Sol. Energy Mater. Sol. Cells 156, 101–111 (2016).

    Article  Google Scholar 

  30. Ercole, P. FRELP 2 Project – full recovery end of life photovoltaic. In Proc. 32nd European Photovoltaic Solar Energy Conference 1775–1783 (WIP GmbH & Co Planungs-KG, 2016).

  31. Huang, W., Shin, W., Wang, L., Sun, W. & Tao, M. Strategy and technology to recycle wafer-silicon solar modules. Sol. Energy 144, 22–31 (2017).

    Article  Google Scholar 

  32. Wang T., Hsiao J. & Du C. Recycling of materials from silicon base solar cell module. In Proc. 38th IEEE Photovoltaic Specialists Conference 2355–2358 (Institute for Electrical and Electronics Engineers, 2011).

  33. Woodhouse, M. Smith B., Ramdas A. & Margolis R. Crystalline Silicon Photovoltaic Module Manufacturing Costs and Sustainable Pricing: 1H 2018 Benchmark and Cost Reduction Roadmap (National Renewable Energy Laboratory, 2019);

  34. Silicon metals. Shanghai Metals Market (2018).

  35. PV spot price. Energy Trend (2018).

  36. Liu, Z. et al. Revisiting thin silicon for photovoltaics: A technoeconomic perspective. Energy Environ. Sci. (2020).

  37. Terheiden, B. et al. Manufacturing 100-µm-thick silicon solar cells with efficiencies greater than 20% in a pilot production line. Physica status solidi (a) 212, 13–24 (2015).

    Article  Google Scholar 

  38. World Energy Outlook 2017: China (International Energy Agency, 2017);

  39. Trends in Photovoltaic Applications 2018 Report IEA PVPS T1–34:2018 (International Energy Agency, Photovoltaics Power Systems Technology Collaboration Programme, 2018).

  40. Ravikumar, D., Wender, B., Seager, T. P., Fraser, M. P. & Tao, M. A Climate Rationale for Research and Development on Photovoltaics Manufacture. Appl. Energy 189, 245–256 (2017).

    Article  Google Scholar 

  41. Peng, J., Lu, L. & Yang, H. Review on life cycle assessment of energy payback and greenhouse gas emission of solar photovoltaic systems. Renew. Sustain. Energy Rev. 19, 255–274 (2013).

    Article  Google Scholar 

  42. Olson, C., Geerligs, B., Goris, M., Bennett, I. & Clyncke, J. Current and future priorities for mass and material in silicon PV module recycling. In Proc. 8th European Photovoltaic Solar Energy Conference and Exhibition 4629–4633 (WIP Wirtschaft und Infrastruktur GmbH & Co Planungs-KG, 2013).

  43. Fu, Y., Liu, X. & Yuan, Z. Life-Cycle assessment of multi-crystalline photovoltaic (PV) systems in China. J. Clean. Prod. 86, 180–190 (2015).

    Article  Google Scholar 

  44. Bohland, J. R. & Anisimov, I. I. Possibility of recycling silicon PV modules. In Proc. 26th Photovoltaic Specialists Conference 1173–1175 (IEEE, 1997).

  45. Frisson, L. Recent improvements in industrial PV module recycling. In Proc. 16th European Photovoltaic Solar Energy Conference and Exhibition (WIP Wirtschaft und Infrastruktur GmbH & Co Planungs-KG, 2000).

  46. Schlenker, S. et al. The second life of a 300 kw PV generator manufactured with recycled wafers from the oldest German PV power plant. In Proc. 21st European Photovoltaic Solar Energy Conference (WIP Wirtschaft und Infrastruktur GmbH & Co Planungs-KG, 2006).

  47. Köntges, M., Kajari-Schröder, S. & Kunze, I. Crack statistic for wafer-based silicon solar cell modules in the field measured by UV fluorescence. IEEE J. Photovoltaics 3, 95–101 (2013).

    Article  Google Scholar 

  48. Reil, F., Althaus, J., Vaassen, W., Herrmann, W. & Strohkendl, K. The effect of transportation impacts and dynamic load tests on the mechanical and electrical behavior of crystalline PV modules. In Proc. 5th World Conference on Photovoltaic Energy Conversion 3989–3992 (WIP Wirtschaft und Infrastruktur GmbH & Co Planungs-KG, 2010).

  49. Morlier, A., Siebert, M., Kunze, I., Mathiak, G. & Kontges, M. Detecting photovoltaic module failures in the field during daytime with ultraviolet fluorescence module inspection. IEEE J. Photovoltaics 7, 1710–1716 (2017).

    Article  Google Scholar 

  50. Philipps, S. & Warmuth, W. Photovoltaics Report (Fraunhofer ISE, 2018).

  51. International Technology Roadmap for Photovoltaic (VDMA, 2018).

  52. Syvertsen, M. et al. Recycling of broken Si based structures and solar cells. In Proc. 32 nd European Photovoltaic Solar Energy Conference 1768–1774 (WIP Wirtschaft und Infrastruktur GmbH & Co Planungs-KG, 2016).

  53. Draoua, A. D. et al. On the fabrication of solar cells based on newly produced recycled silicon feedstocks from Cabriss – a comparative study between material properties and solar cells performances. In Proc. 33rd European Photovoltaic Solar Energy Conference 483–487 (WIP Wirtschaft und Infrastruktur GmbH & Co Planungs-KG, 2017).

  54. Davis, J. R. et al. Impurities in silicon solar cells. IEEE Trans. Electron Devices 27, 677–687 (1980).

    Article  Google Scholar 

  55. Coletti, G. et al. Impact of metal contamination in silicon solar cells. Adv. Func. Mater. 21, 879–890 (2011).

    Article  Google Scholar 

  56. Seigneur, H. et al. Manufacturing metrology for c-Si photovoltaic module reliability and durability, part I: feedstock, crystallization and wafering. Renew. Sustain. Energy Rev. 59, 84–106 (2016).

  57. SEMI PV17–1012 Specification for Virgin Silicon Feedstock Materials for Photovoltaic Applications (SEMI, 2012).

  58. Davis, J. R., Hopkins, R. H. & Rohatgi, A. Definitions of solar grade silicon. In Proc. Third Symposium on Materials and New Processing Technologies for Photovoltaics (Electrochemical Society, 1982).

  59. Naumann, V. et al. Explanation of potential-induced degradation of the shunting type by Na decoration of stacking faults in Si solar cells. Sol. Energy Mater. Sol. Cells 120, 383–389 (2014).

    Article  Google Scholar 

  60. Aasly, K. Properties and Behavior of Quartz for The Silicon Process. PhD thesis, Norwegian University of Science and Technology (2008);

  61. Wender, B. A. et al. Illustrating anticipatory life cycle assessment for emerging photovoltaic technologies. Environ. Sci. Technol. 48, 10531–10538 (2014).

    Article  Google Scholar 

  62. Powell, D. M. et al. The capital intensity of photovoltaics manufacturing: barrier to scale and opportunity for innovation. Energy Environ. Sci. 8, 3395–3408 (2015).

    Article  Google Scholar 

  63. Müller, A., Wambach, K. & Alsema, E. Life cycle analysis of solar module recycling process. MRS Proc. 895, G03–G07 (2005).

    Article  Google Scholar 

  64. Takami, K. et al. Effect of HF and HNO3 concentration on etching rate of each component in waste crystalline silicon solar cells. Mater. Trans. 56, 2047–2052 (2015).

    Article  Google Scholar 

  65. Klugmann-Radziemska, E. & Ostrowski, P. Chemical treatment of crystalline silicon solar cells as a method of recovering pure silicon from photovoltaic modules. Renew. Energy 35, 1751–1759 (2010).

    Article  Google Scholar 

  66. Huang, W. H. & Tao, M. A simple green process to recycle Si from crystalline-Si solar cells. In Proc. 2015 IEEE 42nd Photovoltaic Specialty Conference 1–4 (Institute of Electrical and Electronics Engineers Inc., 2015).

  67. Park, J., Kim, W., Cho, N., Lee, H. & Park, N. An eco-friendly method for reclaimed silicon wafers from a photovoltaic module: from separation to cell fabrication. Green Chem. 18, 1706–1714 (2016).

    Article  Google Scholar 

  68. Dias, P., Javimczik, S., Benevit, M., Veit, H. & Bernardes, A. M. Recycling WEEE: extraction and concentration of silver from waste crystalline silicon photovoltaic modules. Waste Manag. 57, 220–225 (2016).

    Article  Google Scholar 

  69. Doi, T. et al. Experimental study on PV module recycling with organic solvent method. Sol. Energy Mater. Sol. Cells 67, 397–403 (2001).

    Article  Google Scholar 

  70. Huang, W. H., Shin, W. J., Wang, L. & Tao, M. Recovery of valuable and toxic metals from crystalline-Si modules. In Proc. IEEE 42nd Photovoltaic Specialty Conference 3602–3605 (Institute of Electrical and Electronics Engineers Inc., 2016);

  71. Sinha, P., Raju, S., Drozdiak, K. & Wade, A. Life cycle management and recycling of PV systems, Photovolt. Int. 38, 47–50 (2017).

    Google Scholar 

  72. Liang, T. S. et al. A review of crystalline silicon bifacial photovoltaic performance characterisation and simulation. Energy Environ. Sci. 12, 116–148 (2019).

    Article  Google Scholar 

  73. Tamizhmani, G. et al. Evaluating PV module sample removal methods for TCLP testing. In Proc. 2018 IEEE 7th World Conference on Photovoltaic Energy Conversion (WCPEC) 2610–2615 (Institute of Electrical and Electronics Engineers Inc., 2018).

  74. Ravikumar, D., Sinha, P., Seager, T. P. & Fraser, M. P. An anticipatory approach to quantify energetics of recycling CdTe photovoltaic systems. Prog. Photovolt. Res. Appl. 24, 735–746 (2016).

    Article  Google Scholar 

  75. Della Rosa, F. Circular Economy: Solar Panel Recycling. La Mia Energia. Presentation at PV in the Circular Economy Workshop (National Renewable Energy Laboratory, 2019).

  76. Jordan, D. C., Silverman, T. J., Wohlgemuth, J. H., Kurtz, S. R. & VanSant, K. T. photovoltaic failure and degradation modes. Prog. Photovolt. Res. Appl. 25, 318–326 (2017).

    Article  Google Scholar 

  77. Dupuis, J. et al. NICE module technology – from the concept to mass production: a 10 years review. In Proc. 38th IEEE Photovoltaic Specialty Conference (Institute of Electrical and Electronics Engineers Inc., 2012).

  78. What is cradle to cradle certified? Cradle to Cradle Products Innovation Institute (2020).

  79. Sustainability Leadership Standard for Photovoltaic Modules and Photovoltaic Inverters NSF/ANSI 457 – 2019 (National Sanitation Foundation and American National Standards Institute, 2019);

  80. Woditsch, P. & Koch, W. Solar grade silicon feedstock supply for PV industry. Sol. Energy Mater. Sol. Cells 72, 11–26 (2002).

    Article  Google Scholar 

  81. Veolia opens the first European plant entirely dedicated to recycling photovoltaic panels. Veolia (2018).

  82. Wiederverwertung von Photovoltaikmodulen. Suez (2018).

  83. Bestätigte abholvorgänge. Stiftung EAR (2019).

  84. Statistical data set: waste electrical and electronic equipment (WEEE) in the UK. UK Environment Agency (2019).

  85. Rapport annuel du registre des Déchets d'équipements électriques et électroniques: Données 2017. ADEME (French Environment & Energy Management Agency) (2018).

  86. Barème des Écoparticipations (PV CYCLE France, 2020);

  87. Regelsetzung Garantiehöhe (PBÜ). Stiftung Elektro-Altgeräte Register (2018).

  88. A List of Intermediate Processors which can Treat PV Modules Properly (Japan Photovoltaic Energy Association, 2019);

  89. Announcement on Dissolution of Joint Venture (NPC Incorporated, 2019);

  90. Products and Services: Photovoltaic Panels Reuse/Recycling. NPC Incorporated (2019).

  91. Interim Report of Committee for a Mass-Introduction of Renewable Energy and Future Electricity Networks (in Japanese) (Japanese Ministry of the Economy, Trade and Industry, 2019);

  92. SEIA National PV Recycling Program. SEIA (Solar Energy Industries Association) (2019).

  93. Butler, E. PV End-of-life management. AdminMonitor

  94. California Product Stewardship Council, Solar Panel & Battery Recycling. The time to do something is now. AdminMonitor (2019).

Download references


This work was authored in part by the National Renewable Energy Laboratory, operated by Alliance for Sustainable Energy, LLC, for the US Department of Energy (DOE) under contract no. DE-AC36-08GO28308. Funding provided by US Department of Energy Office of Energy Efficiency and Renewable Energy Solar Energy Technologies Office. The views expressed in the article do not necessarily represent the views of the DOE or the US Government.

Author information

Authors and Affiliations


Corresponding author

Correspondence to Garvin A. Heath.

Ethics declarations

Competing interests

The authors declare employment-based competing interests for P.S., A.W. and E.B., and personal financial competing interest for K.W. A.W. is Global Sustainability Director with First Solar, a producer of thin film PV modules. P.S. is Senior Scientist with First Solar. K.W. is the owner of Wambach-Consulting, a sole-proprietorship consulting on sustainability aspects especially of PV systems. E.B. is the senior director of Codes and Standards with the Solar Energy Industries Association. Outside of the employment listed herein and the funding listed in the acknowledgments section, the authors declare no competing interests.

Additional information

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Data 1

Summary characteristics from a review of PV recycling literature.

Rights and permissions

Reprints and Permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Heath, G.A., Silverman, T.J., Kempe, M. et al. Research and development priorities for silicon photovoltaic module recycling to support a circular economy. Nat Energy 5, 502–510 (2020).

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI:

This article is cited by


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing