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

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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.

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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.


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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.

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Correspondence to Garvin A. Heath.

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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.

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Supplementary information

Supplementary Data 1

Summary characteristics from a review of PV recycling literature.

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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).

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