EPA/60Q/R-23/186
June 2023 www.epa.gov
United States
Environmental Protection
Agency
el h S ^ £ 2
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Office of Research and Development
Center for Environmental Solution and Emergency Response
Land Remediation and Technology Division,
Cincinnati, OH 45268
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Sustainable End-of-Life Management of PV-Panels
End-of-Life Management of Photovoltaic
Solar Panels in the United States
Project Officer
Endalkachew Sahle-Demessie
U.S. EPA/Center for Environmental Solution and Emergency Response/Land
Remediation and Technology Division, Cincinnati, OH
11
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Sustainable End-of-Life Management of PV-Panels
NOTICE/DISCLAIMER
The U.S. Environmental Protection Agency, through its Office of Research and Development,
funded the research described herein under an approved Quality Assurance Project Plan (Quality
Assurance Identification Number K-LRTD-0032822-QP-l-l Impact of Materials Management
Application. It has been subjected to the Agency's peer and administrative review and has been
approved for publication as an EPA external document.
Environmental Protection Agency contract with Research Triangle International RTI EPA, 3040
E. Cornwallis Road, Research Triangle Park, NC 27709-2194, through Task Order 37, Task 11
by the United States Environmental Protection Agency (U.S. EPA), Office of Research and
Development. The ORD team acknowledges support and assistance from various EPA
contractors through Contract No. 68HERD20A0004/68HERH20F0355. This document has been
subjected to review by the Office of Research and Development and approved for publication.
Approval does not signify that the contents reflect the views of the Agency, nor does mention of
trade names or commercial products constitute endorsement or recommendation for use. Thus,
the findings and conclusions in this report have not been formally disseminated by the Agency
and should not be construed to represent any Agency determination or policy. Any mention of
trade names, manufacturers or products does not imply an endorsement by the United States
Government or the U.S. Environmental Protection Agency. EPA and its employees do not
endorse any commercial products, services, or enterprises.
111
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Sustainable End-of-Life Management of PV-Panels
Foreword
The U.S. Environmental Protection Agency (US EPA) is charged by Congress with protecting
the Nation's land, air, and water resources. Under a mandate of national environmental laws, the
gency strives to formulate and implement actions leading to a compatible balance between
human activities and the ability of natural systems to support and nurture life. To meet this
mandate, US EPA's research program is providing data and technical support for solving
environmental problems today and building a science knowledge base necessary to manage our
ecological resources wisely, understand how pollutants affect our health, and prevent or reduce
environmental risks in the future.
The Center for Environmental Solutions and Emergency Response (CESER) within the Office of
Research and Development (ORD) conducts applied, stakeholder-driven research and provides
responsive technical support to help solve the Nation's environmental challenges. The Center's
research focuses on innovative approaches to address environmental challenges associated with
the built environment. We develop technologies and decision-support tools to help safeguard
public water systems and groundwater, guide sustainable materials management, remediate sites
from traditional contamination sources and emerging environmental stressors, and address
potential threats from terrorism and natural disasters. CESER collaborates with both public and
private sector partners to foster technologies that improve the effectiveness and reduce the cost
of compliance, while anticipating emerging problems. We provide technical support to EPA
regions and programs, states, tribal nations, and federal partners, and serve as the interagency
liaison for EPA in homeland security research and technology. The Center is a leader in
providing scientific solutions to protect human health and the environment.
Gregory Sayles, Director
Center for Environmental Solutions and Emergency Response
IV
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Sustainable End-of-Life Management of PV-Panels
Abstract
Solar energy is regarded as clean technology, but what happens to solar panels once they reach
the end of their lifetime is vital for sustainability and achieving a circular economy. Current solar
panels have an average lifespan of about 25 years. Millions of solar panels installed from the
early 2000s are approaching the anticipated end-of-life. Growing solar panel waste presents a
new environmental challenge and unprecedented opportunities to create value and pursue new
economic avenues. Increasing interest in panel recycling reflects the relative importance of
recovered materials, primarily silicon, silver, and lead. However, only about 10% of panels are
recycled today.
Currently recycling costs exceed recovery economics, and in the absence of a federal and state
mandates to recycle, a large volume of materials could be headed to a landfill. When released
into the environment, hazardous materials present in end-of-life solar panels can be sources of
significant pollution and health issues. Concern for the heavy metals present is essential to
demand the proper management designed to avoid poor management practices that could
contribute to another recycling crisis. The solar panel industry should develop technology to
enable safe disposal and recycling of end-of-life or reuse and repurposing that could reduce the
amount of waste and virgin materials extraction. Clear criteria and analytical methods should be
developed to evaluate the obsolescence of solar panels to ensure proper management decisions.
Considerations of a landfill option should be replaced with well-managed recycling to avoid
environmental pollution from hazardous materials with PV panels, aid the recovery of valuable
materials present in the panels.
This report supports EPA/ORD effort aimed at understanding the flow of used PV panels by
reviewing the end-of-life of solar PV panels flow projections in the United States at national,
regional, and state levels, and the assumptions and limitations built into the projections. This
report documents a preliminary assessment of available data and development of the model that
can be used as a starting point to track domestic flows of used electronics from generation to
collection and reuse to final disposition.
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Sustainable End-of-Life Management of PV-Panels
Acknowledgement
This report was developed in partnership with RTI International by the United States
Environmental Protection Agency (U.S. EPA), Office of Research and Development. The ORD
team acknowledges support and assistance of subject experts from EPA/Office Resource
Conservation and Recovery and EPA/Region 5 who provided many comments, and suggestion
and other supports.
VI
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Sustainable End-of-Life Management of PV-Panels
Table of Contents
NOTICE/DISCLAIMER iii
Foreword iv
Abstract v
Acknowledgement vi
Figures ix
Tables x
1. Introduction and Background 1
1.1 Report Objectives, Scope, and Organization 1
1.2 National Solar Trends and Projections 1
2. Overview of PV Panel Systems 4
2.1 Solar PV Integration Models 4
2.2 Main Components of PV Panels 5
Solar PV Cells 6
EVA Film 9
Glass 9
Backsheet 9
Aluminum Frame 10
Junction Box 10
2.3 Next Generation Solar Cells 10
3. Projected Quantities of EoL Solar PV Panels by Region and State 11
3.1 Methodology 11
PV EOL Model 11
Installed Solar PV Capacity (MW) 11
Market Share 12
Lifetimes 12
Panel Generation Capacity and Weight 13
3.2 EoL PV Panel Projections 13
3.3 Assumptions 17
4. EoL PV Panel Management Practices 18
4.1 Waste Classification 19
4.2 Storage 21
4.3 Transportation 22
4.4 Secondary Markets, Repair, and Reuse 22
Manufacturer Take-Back Programs 23
Additional Standards and Regulatory Considerations for Panel Reuse and Repair 23
vii
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Sustainable End-of-Life Management of PV-Panels
4.5 Recycling 24
Overview of the PV Panel Recycling Process 25
Waste By-Products from the Recycling Process 28
4.6 Disposal 30
5. State Legislation and Working Groups Leading on Sustainable EoL Management....30
5.1 State Legislation 31
Enacted Legislation 31
Proposed Legislation 33
5.2 State Working Groups 34
6. Current U.S. Recycling Market 34
6.1 PV Panel Recycling Facilities in the U.S 34
6.2 International PV Recycling Facilities 38
6.3 Drivers, Barriers, and Enablers to a Circular Economy 39
7. Future Research Recommendations 45
8. Conclusion 46
9. References 47
Appendix A - EoL Projections Model Documentation 50
Appendix B - EoL Projections by State 52
10. PEER REVIEWERS 57
Vlll
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Sustainable End-of-Life Management of PV-Panels
Figures
Figure 1. U.S. PV Installations by Market Segment, 2015-2020 (GW alternating current;
EIA, 2021) 2
Figure 2. Cumulative Installed PV Capacity, as of December 2020 (MW alternating
current, EIA 2021b) 2
Figure 3. 2050 Projections of Electricity Generation from Solar from Various Sources
(Feldman & Margolis, 2021) 3
Figure 4. IRENA and IEA-PVP 2016 PV EoL Estimates by 2050, Regular-loss and
Early-loss Scenarios (IRENA and IEA-PVP, 2016) 4
Figure 5. Three Typical Solar PV Integration Models 4
Figure 6. Schematic of a PV Cell, Module, and Array (Infinite Power, n.d.) 5
Figure 7. Main Components of a typical c-SI PV Panel (Source Clean Energy Reviews,
Trina Solar) 5
Figure 8. Schematic of CdTe and CIGS thin-film PV panels (U.S. DOE SETO, n.d.) 6
Figure 9. Example of a Solar Module Junction Box (Svarc, 2021) 10
Figure 10. PV EoL Projections Model Process Flow Map 11
Figure 11. PV EoL Projections by Region, 2015 to 2050 (metric tons) 14
Figure 12. Map of the 10 EPA Regions 15
Figure 13. The Top 10 States Projected to Generate the Most EoL PV Panel Waste in
2050 (metric tons) 17
Figure 14. Typical Composition of Different Solar PV Panel Categories (SEIA, 2020). 25
Figure 15. General Process for Recycling Solar Modules (adapted from EPRI, 2018). 26
Figure 16. First Solar Recycling Processes for Laminated Glass and Thin-Film PV Panel
Recycling 26
Figure 17. LCA Schematic of a c-Si PV Waste Recycling Process 29
Figure 18. Location of States with Enacted and Proposed Legislation Focusing on Solar
PV Panel EoL Management 31
Figure 19. Locations of Known Solar Panel Recycling Facilities in the U.S 35
IX
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Sustainable End-of-Life Management of PV-Panels
Tables
Table 1. Major Types of Commercially-Available PV Cell Technology 7
Table 2. Mass Composition of 1,000 kg of C-Si PV Panel Waste as an Input to the
Recycling Process 8
Table 3. First Solar Series 6 PV Module Composition (typical weight) 9
Table 4. Weibull Parameters by Loss Scenario 13
Table 5. Assumptions of Power and Weight by PV Panel Type 13
Table 6. National Incremental PV Panel EoL Projections for the Regular Loss, Mid Loss,
and Early Loss Scenarios (metric tons) 14
Table 7. EoL Mass of Solar PV Projections, 5-year increments, 2015 to 2050 (metric
tons) for the Early Loss, Mid Loss, and Regular Loss (RL) Scenarios by Region... 15
Table 8. Typical Recycling Process for c-Si Solar PV Modules 26
Table 9. Typical Recycling Process for Thin Film Solar Modules 27
Table 10. Summary of Inputs and Outputs of the LCA FRELP Process for Recycling
1,000 kg of c-Si PV Waste Panels (Latunussa et al., 2016) 29
Table 11. Solar Equipment Recycling Facilities in the U.S 36
Table 12. Solar Recycling Companies in Select International Locations 38
Table 13. Drivers to a Circular Economy for PV System Materials 40
Table 14. Barriers to a Circular Economy for PV System Materials 41
Table 15. Enablers to a Circular Economy for PV System Materials 43
X
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Sustainable End-of-Life Management of PV-Panels
1. Introduction and Background
1.1 Report Objectives, Scope, and Organization
The main objectives of this report are to 1) project the mass of end-of-life (EoL) photovoltaic (PV) panels
out to 2050 by state; and 2) evaluate the current solar PV panel recycling market in the United States
(U.S.). Generating predictable waste volumes may help federal, state, and local governments; recyclers;
manufacturers; landfill owners and operators; consumers; and other stakeholders address key challenges
related to sustainable EoL management of solar PV panels. Sustainable EoL management in this context
specifically means the repair, reuse, and recycling of solar PV panels. The scope of the analyses in this
report includes the 50 contiguous states and PV panels that comprise most of the current market (i.e.,
crystalline silicon [c-Si] and thin-film cadmium Telluride [CdTe] panels).
The EPA, its regional offices, and the waste and recycling sector in the U.S. need to begin planning to lay
the groundwork for managing the amount of EoL PV panels sustainably, build the recycling market, and
capitalize on beneficial reuse opportunities. This report seeks to help EPA (including the regional offices)
understand the EoL management practices and projected estimates of PV panels and assess whether
existing recycling technologies and reuse pathways are sufficient to meet the projected PV EoL volume in
the next 20 to 30 years. To that end, this report presents the following information by section:
¦ Section 2 - Overview of PV Panel Systems
¦ Section 3 - Projected Quantities of EoL PV Panels by Region and State
¦ Section 4 - EoL PV Panel Management Practices
¦ Section 5 - State Legislation and Working Groups Leading on Sustainable EoL PV Panel
Management
¦ Section 6 - Assessment of the Current U.S. Recycling Market
¦ Section 7 - Conclusions and Future Research Recommendations.
1.2 National Solar Trends and Projections
Solar power is the fastest growing energy source in the United States. In 2020, 40 percent of new U.S.
electric generation capacity came from solar, compared to 4 percent in 2010, a 36-fold increase (Feldman
& Margolis, 2021). Strong growth is occurring primarily at the utility-scale, where since 2015, new solar
PV installations have more than doubled (see Figure 1). Market growth is being driven by strong federal
and state policies, state renewable portfolio standards (RPS), and increasing demand for clean energy in
public and private consumers. Additionally, module prices are continuing to trend downward, driven by
stronger than expected global demand despite supply disruptions and other challenges caused by the
COVID-19 pandemic and U.S.-imposed tariffs on Chinese products (Feldman & Margolis, 2021). Strong
growth is expected to continue in the near-term resulting from the Biden Administration's clean energy
initiatives (SEIA/Wood Mackenzie, 2021).
1
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Sustainable End-of-Life Management of PV-Panels
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U.S. PV Installations by Market Segment
I Utility-scale
IC&I
I Residential
2015
2016
2017
2018
2019
2020
Figure 1. U.S. PV Installations by Market Segment, 2015-2020 (GW alternating current; EIA, 2021)
The top 10 solar generating states generated more than 5 percent of their electricity from solar in 2020,
with California continuing to serve as the national leader with approximately 22 percent of its total
electncity generation from solar (SEIAAVood Mackenzie, 2021; Feldman & Margolis, 2021). At the end
of 2020, cumulative solar power was reported to range from 73.8 GW of alternating current ((i\\ v . EIA
2021b, see Figure 2) to 95.5 GW direct current (GW SEIAAVood Mackenzie, 2021) of solar PV
systems installed in the U.S., of which the largest share are utility-scale, followed by residential, then
commercial and industrial (C&I).
California
Texas
North Carolina
Florida
Arizona
New Jersey
Nevada
Massachusetts
New York
Utah
Other
23
,603
I Residential
C&I
I Utility-scale
5,000
10,000
15,000
¦ 18,276
ii III
20,000 25,000
Figure 2. Cumulative Installed PV Capacity, as of December 2020 (MW alternating current, EIA
2021b)
The EIA estimates record solar installations in 2021 and 2022: 21 GWag in 2021 and 19 GWag in 2022,
respectively, compared to 15 GWag in 2020. Projections of electricity generation from solar out to 2050
vary by source and modeled scenario (see Figure 3). The NREL's 2020 Standard Scenarios mid-case
2
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Sustainable End-of-Life Management of PV-Panels
version projects the greatest amount of electricity generation from solar. EIA's AEO2021 reference-case
projects 13 percent more electricity generation compared to their AE02020 version, and the
BloombergNEF's New Energy Outlook 2020 scenario is on par with the EIA AE02020. While the
projections vary, solar will continue to expand as states continue to increase their RPS.
6,000
2- 5,000
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I Distributed PV
I Utility-scale PV
I Wind
I Other
renewables
I Nuclear
Other
Coal
Figure 3. 2050 Projections of Electricity Generation from Solar from Various Sources (Feldman &
Margolis, 2021)
Figure note: Data sources include BloombergNEF 2020 (BNEF '20) New Energy Outlook 2020; EIA 2021 (EIA '21)
Annual Energy Outlook, reference case; EIA, 2020 (EIA '20) Annual Energy Outlook; NREL, 2020 (NREL '20) Standard
Scenarios, mid case.
As the solar panel market continues to grow, so will the quantity of decommissioned panels. Some of the
first installed panels are reaching the end of their lifetimes, which is generally estimated at 25 to 30 years.
End of life, in many cases, typically means a PV panel still functions but not as efficiently. Most
operational panels may still achieve 70-80 percent efficiency at 25-30 years (Curtis et al., 2021); however,
they tend to be replaced by more efficient panels. A portion of installed panels may not last to their
expected lifetimes due to low quality, improper citing and installation, and damage from hurricanes, fires,
and other disasters.
The most widely cited estimate of EoL PV panels, the IRENA and IEA-PVPS 2016 report, estimates
nearly 60 million to 78 million metric tons of EoL PV panels globally by 2050. The U.S. is projected to
make up the second-largest global share of this estimate, ranging between 7.5 million and 10 million
metric tons of PV panels as shown in Figure 4 (IRENA-IEA PVPS, 2016). There is anecdotal evidence
that the current PV panel waste is much more than the data presented in Figure 4.
3
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Sustainable End-of-Life Management of PV-Panels
China1
US*
I • Japan'
7.5 million
6.5 million
India1
I Germany'
4.3 million
4.4 million
2050
60-78 million tonnes of
PV panel waste globally
-i 1—
5
—i r-
10
—i r-
15
Cumulative PV panel waste (million t)
Regular-loss scenario ¦ Early-loss scenario
Figure 4. IRENA and IEA-PVP 2016 PV EoL Estimates by 2050, Regular-loss and Early-loss
Scenarios (IRENA and IEA-PVP, 2016).
2. Overview of PV Panel Systems
PV systems are comprised of PV cells and other components, which convert sunlight directly into
electricity. While hundreds of brands and models of PV cells and modules exist, this section describes a
general solar PV module, the major components of widely available PV systems, and a brief discussion
on next generation solar cells.
2.1 Solar PV Integration Models
One of three typical models are referred to when talking about solar PV installations - grid-tied, off-grid,
and hybrid - as illustrated in Figure 5. The main differences include the need for a charge controller and
energy storage solution (i.e. a battery) for electricity generation that is not tied to the grid. All three
models are considered because the focus of this report is on solar panel EoL management.
J Grid-Tied Solar System
Off-Grid Solar System
Hybrid Solar System J
Optional Generator 1 utility Grid
Figure 5. Three Typical Solar PV Integration Models.
4
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Sustainable End-of-Life Management of PV-Panels
2,2 Main Components of PV Panels
The main components of a solar panel or module include the following, in general order of manufacturing
and assembly:
¦ Solar PV cells
¦ Ethylene vinyl acetate (EVA) film (for encapsulation)
¦ Tempered glass (3 to 5 mm thick)
¦ Fluoropolymer as commonly used rear backsheet
¦ Extruded aluminum frame, and the
¦ Junction box (diodes and connectors).
Figure 6 visualizes a cell, module, and array. This report uses the terminology of PV module or panel
when discussing one panel. An installation of panels is an array. Figure 7 presents the individual
components of a typical C-Si PV panel, and Figure 8 presents a schematic of two types of thin-film
panels, CdTe and CIGS for perspective on how construction differs by panel type.
Aluminium Frame
Tempered Glass
Encapsulant - EVA
Solar cells
Encapsulant - EVA
Backsheet
Junction Box
Figure 7. Main Components of a typical c-SI PV Panel (Source Clean Energy Reviews, Trina Solar)
5
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Sustainable End-of-Life Management of PV-Panels
Transparent
eondudive
axitfe (TCO)
CDS
CIGS
Mo
Ciiass,
meat foil,
psasto
Figure 8. Schematic of CdTe and CIGS thin-film PV panels (U.S. DOE SETO, n.d.) Left: Thin
Film-CdTe, Right: Thin-film CIGS.
PV cells are manufactured with at least two layers of semiconductor material, one with a positive
charge and the other negative. When light enters the cell, some of the photons from the sunlight
are absorbed by the semiconductor atoms, freeing electrons from the cell's negative layer to flow
through an external circuit and back into the positive layer. This flow of electrons is what
produces an electric current. The PV panel produces DC and an inverter is used to convert them
to AC. DC energy always flows in the same direction, while AC changes direction frequently.
AC is the standard because it can easily be converted to higher or lower voltages and be
transmitted over long distances. However, household items may use either type of current. For
example, plug-in appliances such as refrigerators, electric ovens, and microwaves run on AC,
while most batteries and, in turn, most electronic devices run on DC. Traditional solar panels
produce DC. The junction box contains connectors, cables, and a bypass diode. Inverters are
used to convert DC energy into AC energy to enable the electricity generated to be used in the
home or sent back to the electric grid Power adapters for electronic devices act as power
converter that converts DC-AC, AC-DC, and DC-DC. They convert the AC grid supply back to
the device's DC power. AC solar panels are a different design where microinverters are
integrated into the PV cells, so a separate inverter does not need to be attached to the panel.
Panels produce only DC. An inverter is needed to obtain AC. The remainder of this section
describes the major components of a generic, commercially available PV module.
Solar PV Cells
The most commercially available PV cells technology includes monocrystalline, polycrystalline,
and thin-film (see Table 1). Concentrating PV and building-integrated PV (BIPV) are
commercially available but make up a very small share of the market and are therefore included
as next generation solar cells in this report (see Section 2.3).
Both monocrystalline and polycrystalline are c-Si technology and are the most common on the market.
Both types require large amount of Si to manufacture, yet polycrystalline panels less efficient than
Glass
Sunlight
Transparent
contfiiaive
oxide (TCO)
n-la/fir
(CdS)
(CdTe)
Aluminum
(bac* contact)
Sunlight
6
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Sustainable End-of-Life Management of PV-Panels
monocrystalline panels. Most residential panels contain 60 mono or polycrystalline cells linked together
to generate 30-40 volts, depending on the type of cell used (Svarc, 2020). Commercial and utility-scale
systems may contain 72 or more cells and operate at a higher voltage. An average home needs
approximately 28 to 34 panels to meet its energy needs (SHDEC, 2020). Thin-film PVs are fast-growing,
are generally less efficient than c-Si, and tend to be cheaper. Some of this growth is due to the increased
demand for clean energy, but growth in their market share is slower.
Table 1. Major Types of Commercially-Available PV Cell Technology
PV Cell
Technology
Relative
Efficiency and
Cost1
Presence on the
Market
Brief Description
Typical Cost
($ per watt)
Monocrystalline
Highest
efficiency (rating
of 20%-25%),
highest cost
Widely; 1st
generation panels
Manufactured from
single Si crystal;
requires large
amount of Si;
requires least area
for a given power;
performance
degrades in low
sunlight conditions
1.59
Polycrystalline
High efficiency
(rating of 15-
20%) although
slightly less than
mono, lower cost
Widely; 1st
generation panels
Manufactured by
fusing different
crystals of Si;
performs best at high
temperatures due to
low thermal
coefficient;
performance
degrades in low
sunlight conditions
1.42
Thin-film:
¦ Cadmium
telluride (CdTe)
¦ Copper indium
gallium selenide
(CIS/CIGS)
¦ Amorphous
silicon (A-Si)
Lower efficiency
(max rating of
12-20%), lowest
cost
¦ Limited; most
firms are start-ups
developing
experimental
technologies
¦ Newest addition
to the market:
CIS/CIGS
Manufactured by
depositing 1 or more
layers of PV material
on substrate;
performs best at high
temperatures;
performance less
affected by low
sunlight conditions;
use less Si than
mono and
polycrystalline
0.67
1 Adapted from Svarc, 2020 and SEIA, n.d.
The efficiency of a PV cell is the amount of electrical power coming out of the cell compared to the
energy from the light shining on it, which indicates how effective the cell is at converting energy from
one form to the other (U.S. DOE SETO, n.d.). The PV cell is composed of semiconductor material, of
which the most used include the following:
¦ Silicon - the most used semiconductor material used in solar cells, representing approximately
95% of the modules sold today (U.S. DOE SETO, n.d.).
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Sustainable End-of-Life Management of PV-Panels
¦ Thin-film CdTe - the second most common PV material after silicon, but not as efficient.
¦ Thin-film copper indium gallium diselenide (CIGS) - these materials have optimal properties, but
combining the four elements is complex, making it challenging to transition from lab to market.
By weight, typical c-Si PV panels today contain about:
¦ 76% glass (panel surface)
¦ 10% polymer (encapsulant and backsheet foil)
¦ 8% aluminum (mostly the frame)
¦ 5% silicon (solar cells)
¦ 1% copper (interconnectors) and
¦ less than 0.1% silver (contact lines) and other metals (mostly tin and lead). (IRENA and IEA-
PVPS, 2016; Sander et al., 2007 and Wambach and Schlenker, 2006).
By weight, CIGS panels today are composed of:
¦ 89% of glass
¦ 7% aluminum
¦ 4% polymers
¦ Small percentages of semiconductors and other metals including copper, indium, gallium and
selenium (IRENA and IEA-PVPS, 2016; Sander et al., 2007 and Wambach and Schlenker, 2006).
Similarly, CdTe thin-film panels consist of:
¦ 97% of glass
¦ 3% polymers
¦ Small percentages of semiconductors and other metals including nickel, zinc, tin, and cadmium
telluride (IRENA and IEA-PVPS, 2016).
Table 2. Mass Composition of 1,000 kg of C-Si PV Panel Waste as an Input to the Recycling Process
Material
Quantity (kg)
% Weight of
Module (wt/wt)
Glass, containing antimony (0.01-1 %/kg of glass)
700
70%
Aluminum frame
180
18%
Copper connector
10
1%
Polymer-based adhesive (EVA) encapsulation layer
51
5.1%
Back-sheet layer (based on polyvinyl fluoride)
15
1.5%
Silicon metal solar cell
36.5
3.56%
Silver
0.53
0.053%
Aluminum, internal conductor
5.3
0.53%
Copper, internal conductor
1.14
0.114%
Various metals (tin, lead)
0.53
0.053%
Total
1,000
100%
Source: Latunussa et al., 2016
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Sustainable End-of-Life Management of PV-Panels
Note: Assuming that 1000 kg of PV waste corresponds to approximately 73 square meters of panels, assuming
panels with a mass of 22 kg and a surface area of 1.6 square meters.
Table 3. First Solar Series 6 PV Module Composition (typical weight)
Material
Quantity (kg)
% Weight of Module (wt/wt)
Glass, front (substrate) and back
(cover) glass
0.043
84.5%
Frame and bars, aluminum
0.717
12.5%
Laminate material, polyolefin
0.009
2.02%
Frame adhesive, silicon-based
adhesive
30.00
0.83%
Junction box and cable assembly,
polyphenylene housing and
halogen-free electrical cables
0.20
0.56%
Semiconductor material, thin-film
CdTe
4.44
0.12%
Bussing material
0.29
0.025%
Total
35.502
100%
Source: Miller, Peters, and Zhavari, 2020
EVA Film
EVA is a polymer layer used to encapsulate the cells and hold them in place during manufacturing. The
EVA film must be durable and tolerant of extreme temperature and humidity because it is a key factor in
preventing moisture and dirt egress into the PV cells, which in turn will decrease long-term performance
of the module. The PV cells are first encapsulated with the EVA before being assembled within the glass
and backsheet.
Glass
The front glass sheet protects the PV cells from the weather (e.g., consistent high or low temperatures,
extreme temperature change) and impact from debris (e.g., airborne debris, hail, branches) depending on
impact speed and density. The glass is high-strength, tempered glass typically 3.0 to 4.0 mm thick (Svarc,
2020). The glass used tends to be high transmissive, which has a very low iron content. An anti-reflective
coating on the rear side helps to reduce losses and improve light transmission. (Svarc, 2020).
Backsheet
The backsheet is the bottom layer of most solar panels and acts as a moisture barrier and final external
skin to provide both mechanical protection and electrical insulation (Svarc, 2020). The most common
backsheet is a fluoropolymer (e.g. Dupont's Tedlar) which presents a challenge for EoL management The
backsheet can be made of different polymers, each offering different levels of protection, thermal
stability, and long-term UV resistance. Some panels may use glass as the rear backsheet instead of a
polymer backsheet because glass is more durable and longer lasting; this translates to a higher cost
product.
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Sustainable End-of-Life Management of PV-Panels
Aluminum Frame
The aluminum frame protects the edge of the laminate section housing the PV cells and provides a solid
structure to mount the panel. Frames are typically aluminium and designed to be lightweight, stiff and
able to withstand extreme stress and loading from high winds (Svarc, 2020).
Junction Box
The junction box is a small, weatherproof enclosure on the panel's rear side. Its main purpose is to
securely attach the cables required to interconnect the panels for an installation. The junction box also
houses the bypass diodes and solar MC4 connectors. Diodes only allow current to flow in one direction,
preventing back current that happens when cells are shaded or dirt)'. Depending on panel manufacture, the
bypass diodes may not last as the PV cells. In most cases, the panels are replaced. Some panels are
manufactured with non-serviceable junction boxes, however. Solar MC4 connectors are weather-resistant
plugs and sockets that allow panels to be connected
Figure 9. Example of a Solar Module Junction Box (Svarc, 2021).
2.3 Next Generation Solar Cells
Researchers are pursuing new PV technologies with the aim of creating a high-efficiency, longer-
performing, and lower-cost system. Indirect benefits may also include easier manufacturing and/or
disassembly, depending on individual R&D goals. Next generation solar cells are not discussed in detail
in this report, but include the following:
¦ Perovskites - made from hybrid organic-inorganic materials
* Organic PV (OPV) - made from organic materials
* Quantum dots
¦ Concentrating PV - Use lenses and mirrors to reflect concentrated solar energy onto high-
efficiency cells; require direct sunlight and tracking systems to be most effective; primarily
located in the desert Southwest U.S.
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Sustainable End-of-Life Management of PV-Panels
Building-integrated PV (BIPV) - Serve as both the outer layer of a structure and generate
electricity for on-site use or export to the grid. Provide savings in materials and electricity costs,
reduce pollution, and add to architectural appeal of a building.
3. Projected Quantities of EoL Solar PV Panels by Region and
State
This section presents the methodology used to project EoL solar PV panels (Section 3.1 and Appendix
A), the projections nationally, regionally, and by state (Section 3.2 and Appendix B), and the
assumptions and limitations built into the projections (Section 3.3).
3.1 Methodology
Several data sources were used in the projections that built on each other. First, installed solar capacity
data were collected, the market share between residential and commercial was calculated, and panel
lifetimes, typical panel generation capacity, and weight were defined. A Weibull function and parameters
similar to those used by IRENA and IEA-PVPS (2016) were used. All data and calculations are presented
in the Excel workbook PV EoL Model. Additional documentation about the worksheets used in the
calculation of PV panel entering EoL management each year between 2010 and 2085 within the model is
provided in Appendix A.
PV EOL Model
An Excl model was developed. Appendix A presents a description of each of the worksheets in the model.
Process flow mapping is captured in Figure 10. The INOUT worksheet is the main user interface and
presents the results nationally and for any specified state or region. The calculations used to estimate the
volume of PV EoL panels generated starts on the PV Capacity worksheet and concludes on the
PV_EOL_Weight worksheet. Supporting datasets are used to further refine the data at each step in the
model's calculations. Panel weights index by consumer type (residential/commercial) and market share
and lifetimes are indexed by consumer segment.
Figure 10. PV EoL Projections Model Process Flow Map
State-level
PV Capacity
Market
Share
(%)type
Lifetimes
(scenario)
Panel
Weights
(IbsJtype
Installed Solar PV Capacity (MW)
Solar Energy Industries Association (SEIA) provides data on solar energy installed by state and economic
quarters. Data used in the model has been updated as of Q4 2020. SEIA contains data by U.S. state on PV
MW installed, number of PV installations, national ranking, solar companies, growth projection, and
11
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Sustainable End-of-Life Management of PV-Panels
growth projection rank. SEIA data was used to predict future growth projections of PV by state between
2021 through 2024.
The EIA's 2020 Annual Energy Outlook (AEO) projections of solar PV capacity growth for the years
between 2025 and 2050 were used to supplement the SEIA state capacity data. A national average annual
growth rate of 6.8 percent is applied to extend the projected growth in PV capacity out to mid-century.
Market Share
Market shares are the percentage of total installed solar PV capacity in 2019 for two customer segments
(residential versus commercial). This calculation relies on three datasets from EIA:
¦ EIA-861, Non-Net Metering Distributed Capacity (MW), and Net Metering Capacity (MW).
¦ EIA-860, Existing nameplate Capacity Energy Source, Producer Type and State.
To calculate the market share, the residential capacity from the two EIA-861 datasets were summed. For
simplicity we assumed that the commercial segment includes all non-residential installed PV capacity
(commercial, industrial, and electric utilities). After combining these three datasets, the percentage of
total installed solar PV capacity by state was calculated.
Lifetimes
An assumption of 30-year average panel lifetime was usedl. Both early-loss and regular-loss scenarios
were modelled using the Weibull function based on the following formula:
Fit) = 1 - e {t}
Where t is time in years, T is average lifetime, and a is the shape factor which controls the typical S shape
of the cumulative Weibull curve.
The same parameters used in IRENA-IEA PVPS, 2016 were used, including alpha shape factors of
2.4928 (Frischknecht, et al., 2016) and 5.3759 (Kuitsche, 2010; Zimmerman. 2013), to model early-loss and
regular-loss scenarios, respectively. The regular loss assumes a 30-year lifetime. The early loss scenario
accounts for infant, mid-life, and wear-out failures before 30 years. The early-loss scenario represents
failures requiring panel replacement such as broken glass, broken cells, ribbons and cracked backsheet
with isolation defects; however, only panels with serious functional or safety defects requiring full
replacement are included in the alpha factor (Frischknecht, et al., 2016). Early loss may be caused by
factors such as damage during transit or installation, or exposure to harsh weather conditions. The early-
loss shelf life of solar modules is estimated to contribute more than 80 percent to the solar module
recycling market in 2017 (Holm and Martin, 2019). As noted in IRENA-IEA PVPS (2016):
¦ 0.05% of installed modules fail annually
¦ 0.05% of modules fail before leaving manufacturer per year, and
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Sustainable End-of-Life Management of PV-Panels
¦ 2% of modules are broken in production per year.
The model provides a third scenario (mid loss) that represents a middle of the road scenario with an alpha
factor of 3.6.
Table 4 presents the parameters used by loss scenario. The larger the alpha used in the Weibull function,
the steeper the curve and a higher probability of loss from 30 years on which is represented in the regular-
loss scenario. The early-loss scenario uses a smaller alpha resulting in a flatter curve and more loss earlier
in the life-span of the panel.
Table 4. Weibull Parameters by Loss Scenario
Scenarios
a (shape)
t (scale)
Regular Loss
5.3759
30
Early Loss
2.4928
30
Mid Loss
3.6
30
Panel Generation Capacity and Weight
Solar panel size and weight were collected from Intermountain Wind & Solar. Commercial and
residential panels vary in size and weight based on the number of cells.
The capacity per panel is used to convert annual incremental installments of PV capacity (MW) to the
number of PV solar panels installed each year. The panel weight is multiplied by the number of new
panels installed each year to estimate the total installed weight.
For the purposes of this model, the difference in panel weight across the two customer segments
(residential and commercial) are captured. There are different panel arrangements although the types of
panels for residential and commercial are similar. Residential PV panels are, on average, 65 inches by 39
inches and 33 pounds (lbs) to 50 lbs. Commercial PV panels are, on average, 78 inches by 39 inches and
50 lbs or more. PV panels range from 60 to 72 cells for residential and commercial, respectively.
The midpoints of the weight ranges found in the literature are used in the model. Table 5 presents the
assumed capacity per panel and panel weight for the residential and commercial customer segments.
Table 5. Assumptions of Power and Weight by PV Panel Type
Panel Type
Capacity (watts/panel)
Average Panel Weight (lbs)
Residential
350
40
Commercial
400
50
3.2 EoL PV Panel Projections
By 2050, there may be 7.9 million to 9.1 million metric tons of EoL PV panels nationally between the
regular loss and early loss scenarios, as presented in Table 6. These estimates align relatively well with
the IRENA and IEA-PVPS (2016) estimates for the U.S. of 7.5 million to 10 million metric tons of panel
waste by 2050. The projections do not match exactly due to different data sources (i.e., the IRENA
authors had additional information from industry and a bigger data set to work with).
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Sustainable End-of-Life Management of PV-Panels
Appendix B presents incremental totals for all three scenarios by state. The estimates only present the
total mass of panels that may reach EOL status; no estimates in terms of the management pathways for
the EoL PV panels. Additionally, no estimates of PV EoL panels from installations in Puerto Rico and the
U.S. territories are included.
Table 6. National Incremental PV Panel EoL Projections for the Regular Loss, Mid Loss, and Early
Loss Scenarios (metric tons)
Year
Regular Loss
(metric tons)
Mid Loss
(metric tons)
Early Loss
(metric tons)
2015
16
611
6,834
2020
2,153
25,985
131,051
2025
36,357
184,222
506,311
2030
236,255
657,479
1,281,707
2035
925,865
1,676,217
2,544,631
2040
2,531,027
3,358,850
4,212,169
2045
5,059,933
5,606,635
6,302,028
2050
7,883,322
8,267,484
9,087,051
Figure 11 presents a graph of the PV panel EoL projections by Region, followed by a map of the EPA
regions (Figure 12) for reference. Table 7 presents the numerical PV panel EoL projections by region.
The graph shows, for all regions, that PV panel waste begins to increase rapidly beginning in 2035 with
Regions 9, 4, and 6 potentially generating the greatest mass of PV panel waste by 2050.
2,500,000
2,000,000
c
0
4->
u
1 1,500,000
oi
10
OJ
c
S. 1,000,000
>
Q.
I
o
LU
500,000
0
Figure 11. PV EoL Projections by Region, 2015 to 2050 (metric tons)
2015 2020 2025 2030 2035 2040 2045 2050
14
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Sustainable End-of-Life Management of PV-Panels
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Figure 12. Map of the 10 EPA Regions
Table 7. EoL Mass of Solar PV Projections, 5-year increments, 2015 to 2050 (metric tons) for the
Early Loss, Mid Loss, and Regular Loss (RL) Scenarios by Region
Region
by
Scenario
2015
2020
2025
2030
2035
2040
2045
2050
EL
6,834
131,051
506,311
1,281,707
2,544,631
4,212,169
6,302,028
9,087,051
1
360
6,899
26,096
62,783
123,527
212,948
352,066
600,297
2
460
8,812
34,000
84,385
160,476
250,499
344,464
438,588
3
275
5,269
21,240
60,097
129,169
223,730
342,368
495,361
4
1,361
26,094
100,465
251,222
493,287
810,935
1,210,180
1,750,635
5
244
4,683
20,403
79,828
237,605
532,609
1,035,519
1,891,342
6
661
12,671
52,846
164,594
380,671
690,970
1,089,181
1,590,940
7
44
847
3,614
12,072
29,528
55,726
90,635
135,820
8
281
5,379
21,449
60,207
130,150
227,649
352,042
512,173
9
3,017
57,843
216,216
480,891
810,065
1,127,067
1,373,321
1,526,152
10
133
2,555
9,982
25,629
50,152
80,037
112,252
145,745
ML
611
25,985
184,222
657,479
1,676,217
3,358,850
5,606,635
8,267,484
1
32
1,368
9,641
33,377
82,711
164,960
285,070
464,260
2
41
1,747
12,385
43,906
109,577
211,659
333,634
449,047
3
25
1,045
7,495
28,538
78,694
168,663
296,850
452,942
4
122
5,174
36,647
129,986
328,375
652,104
1,080,263
1,586,307
5
22
929
6,797
30,687
110,883
310,002
703,319
1,385,807
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Sustainable End-of-Life Management of PV-Panels
Region
by
Scenario
2015
2020
2025
2030
2035
2040
2045
2050
6
59
2,512
18,195
73,285
216,790
493,759
913,455
1,445,866
7
4
168
1,224
5,135
16,012
38,186
73,512
120,555
8
25
1,067
7,627
28,757
79,089
170,115
301,728
465,042
9
270
11,469
80,608
270,788
620,784
1,083,482
1,512,320
1,750,719
10
12
507
3,603
13,019
33,302
65,920
106,485
146,939
RL
16
2,153
36,357
236,255
925,865
2,531,027
5,059,933
7,883,322
1
1
113
1,912
12,300
47,210
126,117
247,928
394,102
2
1
145
2,445
15,867
61,773
166,131
320,965
466,591
3
1
87
1,464
9,722
39,947
116,447
252,467
428,950
4
3
429
7,238
46,949
183,129
497,018
983,457
1,513,232
5
1
77
1,304
9,097
43,140
156,468
446,277
1,036,442
6
2
208
3,525
23,845
102,241
315,662
733,533
1,340,360
7
0
14
236
1,616
7,155
23,063
56,370
108,638
8
1
88
1,494
9,874
40,338
117,183
254,131
434,925
9
7
950
16,029
102,354
382,649
962,778
1,665,095
2,009,551
10
0
42
709
4,631
18,282
50,162
99,709
150,530
The top 10 states projected to generate the largest amount of EoL solar PV panels under the Regular Loss
scenario by 2050 are California, Texas, Florida, New York, Nevada, North Carolina, Indiana, Colorado,
Arizona, and Virginia as presented in Figure 13. These states somewhat align with the states that
currently have the largest installed solar electricity generating capacity in 2021. The exceptions are New
Jersey, Massachusetts, and Georgia, which are currently in the top 10 generating capacity in 2021; these
states "replace" Indiana, Colorado, and Virginia (see the PV_Capacity tab in the PV_Waste_Model
workbook).
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Sustainable End-of-Life Management of PV-Panels
1,600,000
1,400,000
c 1,200,000
o
i 1,000,000
dJ
£.
800,000
(u
c
600,000
>
Q.
O 400,000
LU
200,000
0
2010 2015 2020 2025 2030 2035 2040 2045 2050
Figure 13. The Top 10 States Projected to Generate the Most EoL PV Panel Waste in 2050 (metric
tons)
3.3 Assumptions
Several assumptions were made to develop the EoL PV panel estimates as summarized below.
¦ Disaggregating the national IRENA estimates to state data without all of the IRENA inputs is not
straightforward. The method used to project EoL PV panels includes publicly available data plus
the IRENA (2016) methodology assumptions.
¦ The EoL weight projections assume a standard weight for residential versus commercial panels.
¦ Curtis et al. (2021a) notes that the IRENA 2016 report estimates may be underestimated, but no
analysis identifying where or how the IRENA estimates may be underestimated are included in
the report or presented elsewhere. Areas of underestimation likely include the mid loss scenarios
where panels are removed due to a change in homeowner or upgrade to newer, or more efficient
technology.
¦ EoL PV projections by state are based on the state's actual and projected electricity generation
capacity. Transboundary or international exports of EoL PV panels are not incorporated.
¦ State projections, in general, do not specifically factor in any new state legislation (i.e., after the
IRENA estimates were published, 2016 and later). States such as Washington that will require
manufacturer takeback programs will impact estimates of PV EoL projections.
¦ The designation of solar PV panels as universal waste in California may impact the EoL
projections if more panels are repaired or refurbished for the secondary market.
¦ The quantity of panels circulating in the secondary market in the U.S. and those exported from
the U.S. is not considered and data have not been found to date.
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Sustainable End-of-Life Management of PV-Panels
¦ The EoL projections do not include any data for U.S. Territories and the Commonwealth of
Puerto Rico.
¦ The EoL projections do not include off-grid equipment, which may be larger for residential
versus commercial situations.
4. EoL PV Panel Management Practices
EoL may occur in any of the following situations:
¦ The end of the period or performance for a solar project (decommissioning)
¦ Early failure including damages during shipping and installation
¦ Mid-life failure
¦ Identified safety issues
¦ Economic viability
¦ End of expected life failure (the general rule of thumb is 25 to 30 years)
¦ Damage from weather (e.g., hail, extreme winds) and natural disasters (e.g., hurricanes, flooding,
fires)
¦ Homeowners who choose to un-install an existing solar installation
¦ Waste generated from solar panel manufacturing
¦ A generator who decides to discard unused solar panels
¦ Panels that were found (illegally dumped or abandoned), and
¦ Replaced parts (e.g., inverters) from panel refurbishment.
Decommissioning of a solar project may include any of the following (Enbar, 2016):
¦ Equipment removal, disposal, and recycling
o Inverters and other electronic components
o Module mounting structures
o Concrete
o Electrical equipment
o Wiring
¦ Equipment abandoned in place
o Underground conduit
o Certain structures that pose no environmental harm
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Sustainable End-of-Life Management of PV-Panels
¦ Equipment reuse
o Infrastructure improvements (roads, fences)
o Substations, communication towers
o Maintenance building.
Sustainable EoL management practices - renewal, reuse, recycling - are generally desired more than
disposal or abandoning in place by the solar industry and PV panel owners and operators when panels
reach their EoL. EoL does not always mean a PV panel, or its components are no longer operational, but
in today's thinking, PV supply chains in the U.S. tend to be characterized as linear instead of circular.
Few PV manufacturers design for extended product durability, reuse, or recycling (specifically in terms of
ease of disassembly and extraction of valuable materials for recovery). Limited PV panel take-back
programs exist in the U.S.; the classification certain types and brands of PV panels as hazardous and state
policy and regulations are perceived as barriers to reuse and recycling; and the secondary market in the
U.S. is growing, but still has low consumer confidence and may remain low due to performance
uncertainty of the reused panels. (Curtis et al., 2021).
This section provides a summary of solar panel waste classification (as it relates to material storage,
handling, and disposal in Section 4.1), followed by a summary of EoL management practices of storage
(Section 4.2); transportation (Section 4.3); secondary markets, repair and reuse (Section 4.4); recycling
(Section 4.5); and disposal (Section 4.6).
4.1 Waste Classification
Because solar panels may consist of components that are themselves, at certain levels, considered
hazardous (e.g., silver, copper, lead, arsenic, cadmium, and selenium), someone must first determine they
are indeed a 'waste" or 'discarded material" and then confirm whether that waste is hazardous. When PV
panels are improperly handled and/or disposed, the potential risk of hazardous materials leaching into the
environment and spontaneous fire increases.
EoL solar equipment, when considered a waste, is regulated under RCRA as a non-hazardous, hazardous,
or universal waste. Subtitle D of RCRA grants authority to states to regulate non-hazardous solid waste at
an equal or less stringency than the federal regulations. States may also delegate regulatory authority to
local governments, which may result in different regulations across jurisdictions, adding to the
complexity of EoL management.
Residential PV system equipment that is considered solid waste may be excluded from the definition of
hazardous solid waste and RCRA hazardous waste regulations in some U.S. jurisdictions (40 CFR
Section 261.4(b)) because EPA considers it household hazardous waste (HHW). HHW must meet two
requirements:
¦ The waste must be generated by individuals on the premise of a temporary or permanent
residence, and
¦ The waste stream must be composed primarily of materials found in wastes generated by
consumers in their homes.
NREL (2021) notes that these criteria are unclear for residential PV systems. Some may not believe
residential PV systems meet the two criteria defined above, and it is unclear whether a residential PV
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Sustainable End-of-Life Management of PV-Panels
system still retains its HHW designation after it is decommissioned and passed to a third-party for
handling, transport, storage, and EoL management.
For non-residential sources of solar panel waste, the person that determines whether solar equipment is a
solid waste is responsible for proper management. As noted in NREL (2021), anecdotal evidence suggests
there is confusion about when PV equipment becomes a solid waste and is subject to RCRA regulation.
California is working clarify when PV modules are considered solid waste through guidance that states
PV modules are considered solid waste when they are disconnected or removed from service, which may
prompt a reuse determination on-site.
Under RCRA, the person or entity that determines the solar equipment is a solid waste is referred to as a
generator. Generators may be subject to RCRA regulations unless an exclusion applies, including
designation as a household hazardous waste, universal waste, or in some circumstances, if the discarded
PV equipment is destined for recycling. If an exclusion does not apply, the generator needs to make a
hazardous waste determination using acceptable knowledge. Acceptable knowledge may include
processing and manufacturing inputs, products, by-products, and intermediaries; chemical or physical
characterization of the waste, information on the chemical and physical properties of the chemicals used
or produced by the process or otherwise contained in the waste; analytical testing confirming the waste
properties, or other reliable information. If acceptable knowledge is not available, sampling and analyses
must be performed using an approved method such as the Toxicity Characteristic Leaching Procedure
(TCLP) to confirm whether the solar equipment contains hazardous waste. PV modules that fail the TCLP
must follow applicable hazardous waste regulations, while those that pass must follow applicable non-
hazardous solid waste regulations. Standard TCLP may underestimate the hazard, as the hazardous
materials are sealed under the encapsulant. If the encapsulant is intact, it is difficult to see the true level of
hazard. Additionally, states may require additional and different testing to the TCLP test, which may
subject the waste to state-specific hazardous waste regulations.
Solar panels that do or may contain hazardous material include the following:
¦ CdTe panels due to cadmium
¦ Gallium arsenide (GaAs) panels due to arsenic
¦ Some older Si solar panels due to hexavalent chromium coatings and lead solder, while all silicon
panels produced today still use lead solder containing -10 g of lead and
¦ Newer, thin-film CIS/CIGS panels due to copper and/or selenium
¦ Panels with electronic components (e.g., drivers, inverters, circuit boards) because they typically
contain hazardous constituents such as lead, arsenic, cadmium, selenium, and chromium.
Studies presenting TCLP results for PV modules are highly variable and may produce different results
depending on the sample location on the module, the method of sample removal, the test laboratory's
protocols when conducting the TCLP analysis, and other factors such as the condition of encapsulant
(Curtis et al., 2021a).
Certain PV equipment may be excluded from the definition of hazardous waste, when the following
applies; however, state programs may or may not adopt all the federal exclusions listed below:
¦ Metal frames from PV system modules - included under RCRA as scrap metal, including
processed scrap metal, unprocessed home scrap metal, and unprocessed "prompt" scrap metal that
is intended for recycling (40 CFR part 273.9).
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Sustainable End-of-Life Management of PV-Panels
¦ Hazardous secondary material that includes the following when certain regulatory conditions are
met:
o Generated and legitimately reclaimed within the U.S. or its territories that is under
control of the generator (40 CFRpart 261.4(a)(23)).
o Generated and then transferred (40 CFR part 261,4(a)(24).
o Exported from the U.S. and reclaimed at a reclamation facility in another country (40
CFRpart 261.4(a)(25)).
The solar panel manufacturer may be best suited to determine if the panel should be handled as a
hazardous or non-hazardous waste. Panel owners should have the documentation regarding what
technology and brand was installed, which can help with the determination. A waste generator may
forego sampling and analytical testing, though documentation supporting the determination must be
maintained and made available for review by the designated regulatory authority. There is one exception
if the solar panel equipment is considered a hazardous waste that allows for the generator to less follow
less stringent regulations. An approved subset of hazardous wastes may be classified as universal wastes
under RCRA. EPA's universal waste regulations streamline the hazardous waste management standards
for certain categories of hazardous waste to promote the collection and recycling of universal waste, ease
the regulatory burden on retail stores and other generators that wish to collect and transport these wastes,
and to encourage the development of municipal and commercial programs to reduce the quantity of these
wastes going to MSW landfills or combustors. The federal universal waste regulations are found in 40
CFR Part 273 and apply to five types of universal waste:
¦ Batteries
¦ Pesticides
¦ Mercury-coating equipment
¦ Lamps, and
¦ Aerosols.
As of mid-2021, solar panels have not been nationally designated as electronic waste or as universal
waste at the federal level. However, individual states may petition EPA to classify solar panels as
electronic or universal waste. To do so, the relevant state agency must apply to EPA for review and
approval. To date, only California has petitioned to add solar panels to their universal waste program. The
change was approved by EPA in 2020, which is expected to promote solar panel recycling and reuse over
landfilling. Prior to this change (as of January 1, 2021), solar panels were subject to California's
hazardous waste regulations. All other states require a hazardous waste determination.
4.2 Storage
While not a permanent solution, solar panels may be stored for later EoL management, or for later repair
if applicable. Long-term storage of large quantities of solar panels is largely applicable to manufacturers,
waste haulers, utilities, and select commercial and industrial installations where the commercial or
industrial company owns and operates the panels. Long-term storage is applicable to residential
homeowners.
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Sustainable End-of-Life Management of PV-Panels
Until a determination confirms a panel is not hazardous, storage and handling of the panels must follow
RCRA or state hazardous waste regulations. Solar panels cannot be accumulated and consolidated with
universal waste electronic devices if the solar panels are determined to be hazardous. This applies to
broken panels as well. Broken pieces must be cleaned up and properly packaged/containerized as to
minimize the potential release, with structurally sound containers to prevent releases such as leaks
(NCDEQ, 2019).
Solar panels are typically placed in storage containers or warehouses where they are protected from the
weather. Long-term storage is common practice, and even recommended by EPRI until the recycling
market becomes widely available and more cost-effective (Enbar, 2016). As noted above, solar panel
waste may need to be stored according to hazardous waste regulations if applicable and separate from
other universal wastes unless the waste is being stored in a state where solar panel waste is classified as a
universal waste (i.e., California).
Under CA's universal waste requirements, handlers may accumulate PV solar panels for up to one year,
while the general hazardous waste requirements only allow for accumulation for 90 days (for large
quantity generators). The longer accumulation period allows handlers to transport the panels to
destination facilities in bulk and theoretically on a less frequent basis, which may lower transportation
costs. Universal waste requirements also require fewer labeling and recordkeeping requirements
compared to general hazardous waste.
4.3 Transportation
PV equipment regulated as hazardous waste may be subject to additional transportation requirements
including specific packaging, documentation, and other transit-related requirements for highway, rail, air,
or water transport. The Department of Transportation (DOT) Hazardous Materials Regulations should be
consulted for specific requirements. RCRA hazardous waste and universal waste requirements may apply
for international transboundary export (40 CFR parts 260.10, 273.9).
4.4 Secondary Markets, Repair, and Reuse
Secondary or after markets bring together buyers and sellers to trade commodities that have previously
been introduced to a primary market. A secondary market supplies spare parts, accessories, second-hand
equipment, and other goods and services used in repair and maintenance. In the U.S., solar manufacturing
capacity is around 6 GW, which amounts to less than half of the estimated demand forecasted by
SEIA/Wood Mackenzie (2021). Demand is being driven by consumer perception of grid reliability and
the desire to be self-sufficient; uncertainties surrounding natural disasters and the desire to be off-grid;
consumers looking for affordable alternative energy systems; more efficient technology available, inverter
and other equipment replacement in conjunction with the need to comply with more stringent fire,
building, and electrical standards and codes; early retirements of equipment; and tax incentives
(SEIA/Wood Mackenzie, 2021; Curtis et al., 2021a). The secondary market can serve several duties at
once by filling critical supply chain gaps, reducing environmental and social impacts from mining raw
materials, conserving resources, creating new jobs, and keeping solar panel waste out of the landfill.
Secondary markets exist in the U.S., Latin America and the Caribbean, Middle East, Africa, and Asia.
Afghanistan, Pakistan, Djibouti, Somalia, and Ethiopia have the strongest secondary markets, largely off-
grid, and have plenty of sun radiation to justify energy production from used (versus new) solar panels.
However, these reuse panels have shorter lifetime and many of the developing countries lack the
capability to recycle solar panels. Used solar panels in working order, or with high potential for repair and
refurbishment are commonly sold for off-grid applications for residential energy, cold storage, solar well
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Sustainable End-of-Life Management of PV-Panels
pumps, Wi-Fi, solar irrigation, battery charging, and other uses (World Bank, 2020). Second-hand solar
panels are also commonly purchased for replacement parts (as part of repowering a solar panel system)
and price-conscious consumers. Industry experts note that any panel less than 10 years old and ranges
from 100 W to 350+W has resale value, with the average price approximately 50-75 percent less than
new modules and starting at $0.10/W (Schmid, 2021). Wood Mackenzie (2021) estimates the repowering
of existing solar equipment to replace inverters that have reached their 10-year lifespan to reach 800
GWdc between 2021 and 2025.
A comprehensive list of solar businesses involved in the secondary market does not exist and there are
limited companies exclusively dedicated to solar panel repair and reuse. One challenging aspect is the
number of different module designs and composition, which makes it harder to automate disassembly for
repair and reuse. Standards for PV module and equipment repair are not publicly available, which
requires additional effort on the service providers to learn the ins and outs of various brands and models.
Several other barriers to the secondary market are synthesized in Section 6.3 (Drivers, Barriers and
Enablers to a Circular Economy).
EnergyBin (www.energybin.com), a members-only business-to-business (B2B) online exchange network,
appears to be the leader in this space with more than 1,000 solar companies as members, including solar
panel manufacturers and makers of solar equipment, distributors and suppliers, developers, EPCs,
installers and O&M companies. Members list or seek solar components for sale or resale. Solar installers
may also be entering the secondary market. B2B Solar (www.b2bsolarenergy.com) is one example of a
solar installer that recently tapped into the secondary market to find consumers for the overproduction of
solar equipment. B2B Solar is based in Texas and appears to focus on that region, whereas EnergyBin has
national reach.
Missionary or donation-based work is another avenue for the reuse of solar panels and equipment. For
example, Working for the Son Solar (WFTSS) is a 501c3 charity providing donated and repurposed PV
components to families in Mexico. They have also worked with California State University - Fresno
researchers to repair panels, including those with cracked glass, for reuse. Another example, Good Sun,
works with members of local schools and government agencies in Nevada County. Good Sun
conceptualized a repowering program in Nevada (Re-Power) after winning a DOE grant in 2017 which
leverages used solar equipment to install solar PV at local schools, municipal buildings, and low-to-
middle income homes. Good Sun also delivers educational and vocational trainings, and seeks to support
community connectedness and cultural preservation.
Manufacturer Take-Back Programs
Very little information is available on manufacturer take-back programs through internet searches on
'manufacturer take-back program" or 'OEM take-back". First Solar is the most well-known solar company
with a take-back program. This is likely because there is little incentive for industry to invest in PV
recycling, repair, or reuse due to current market conditions and regulatory barriers. This may change in
the short-term as a direct result from the recently enacted legislation in Washington state requiring PV
module manufacturers to finance and implement the takeback and reuse or recycling of PV modules at no
cost to owners.
Additional Standards and Regulatory Considerations for Panel Reuse and Repair
Local regulations should be reviewed when planning to reuse PV panels and equipment during any of the
following phases: project design reviews, construction permits, permits to operate, land-use permits, and
community planning and zoning. Specifically, reusing PV panels and system components may be limited
in jurisdictions that have incorporated any of the following codes and standards:
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Sustainable End-of-Life Management of PV-Panels
¦ The Institute of Electrical and Electronic Engineers (IEEE) 1547 equipment standard
¦ The UL 1741 testing standard
¦ Section 1509.7.2 of the International Code Council's (ICC) International Building Code, and
¦ The National Fire Protection Association's National Electric Code Section 690.12.
California, New England, and Hawaii have incorporated the IEEE 1547 equipment standard and the UL
1741 testing standard into their interconnection regulations, which may prohibit the reuse of older PV
modules for grid-tied rooftop and ground-mounted applications if the projects do not use smart inverters
with the reused panels, or if the design is otherwise out of compliance (Curtis et al., 2021b; IEEE, 20218).
Jurisdictions that have adopted Section 1509.7.2 of the ICC's International Building Code as a fire and
building regulation can prohibit the reuse of older PV modules that is not equivalent to already approved
roof coverings in fire rating classification (Curtis et al., 2021b). State and local electrical regulations may
also prohibit the reuse of PV systems and equipment such as inverters in rooftop and building-mounted,
grid-tied and off-grid applications.
4.5 Recycling
Most PV panels on the global market (i.e., c-Si, CIGS, and CdTe PV panels) are composed of similar
materials such as glass, aluminum, and semiconductors; however, recycling solar modules is complex due
to the different brands and model designs of PV panels, which may require different methods of
disassembly and processing. Glass and aluminum comprise approximately 80-90% by weight of most PV
panels as shown in Figure 14. Each PV panel component needs to be dissembled and separated to be
recycled properly. Additionally, because the modules were designed for durability versus disassembly,
they are not easy to take apart and the potential to damage the solar cells which contain the most valuable
materials is high; only the undamaged solar cells can be recovered and reused in new products.
Although a recycling solution is technically feasible, incentives for consumers, peer influence, and
attitudes towards recycling reflect the real-world situation and help develop practical strategies toward a
circular economy (Deng et al., 2021; Walzberg, 2021)
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Sustainable End-of-Life Management of PV-Panels
op
o
2014
2030
2014
2030
Phase-out expected before 2030
2014
cn
CD
O
2030
2014
o
2030
o%
I Aluminium
I Copper
10%
20%
30%
40%
50%
60%
70%
Compound Conductor | other Meiais (Zn, Ni, Sn, Pb, Cd. Ga, In. Se, Te)
Glass | Polymer
30%
I Sealants
I Silicon
90% 100%
Silver
Figure 14. Typical Composition of Different Solar PV Panel Categories (SEIA, 2020)
Overview of the PV Panel Recycling Process
The general process for recycling is presented in Figure 15. First, the frame is disassembled from the
module, followed by the wires and junction box. The modules may undergo coarse crushing to make this
process easier. The sandwiched panel is delaminated to recover the glass, silicon, EVA, and other metals,
which can be sold for repuiposing. Anything that cannot be repurposed will be contained as HazMat for
proper disposal or sent to, most likely, an industrial versus municipal waste landfill. Wide-scale
commercial application of this process is still in development.
Figure 16 and Table 8 and Table 9 summarize the recycling processes for c-Si panels and thin film
panels, respectively.
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Sustainable End-of-Life Management of PV-Panels
Figure 15. General Process for Recycling Solar Modules (adapted from EPRI, 2018)
Figure 16. First Solar Recycling Processes for Laminated Glass and Thin-Film PV Panel Recycling.
Left: Process for Laminated Glass, Right: Process for Thin-Film Panel Recycling.
Pre-crushing
Manual sorting
Magnetic separator
Fine crushing
Screening
Non ferrous separator
Extraction Unit
Color based sorting
Automatic sampling
Glass Cullet
Fine grain,
foil
Foil
EVA glass separation
'
Clean glass
material
V
cullet
-i
Metals precipitation
Tellurium and Cadmium
separation and recycling
\
Tellurium
product
>>
r >
Cadmium
product
>
Source: Weekend, Wade, & Heath, 2016.
Table 8. Typical Recycling Process for c-Si Solar PV Modules
Tech.
Process
Advantages
Disadvantages
Delamination
Physical disintegration
Efficient waste handling
Other materials mix with
EVA
Damage to solar cells
Apparatus decomposition
Thinner dissolution
Organic layer removal from
glass
Time necessary for
delamination depends on
area
Waste chemical reuse
Expensive equipment
Simple removal of EVA
Hazardous for human
health
Nitric acid dissolution
Complete removal of EVA
and metal layer from the
wafer
Dangerous emissions
Possible recovery of the
whole cell*
Cell defects due to
inorganic acid
Thermal treatment
EVA fully eliminated.
Involves high energy
consumption.
By reusing wafers, possible
to regain whole cell
Dangerous emissions
Used as a supplementary
process to accelerate
dissolution process
Very costly process
26
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Sustainable End-of-Life Management of PV-Panels
Tech.
Process
Advantages
Disadvantages
Ultrasonic irradiation
Simplified removal of EVA.
Waste solution treatment.
Material
Separation
Dry and wet
mechanical process
Non-chemical process.
No removal of dissolved
solids
Simple process.
Requires low energy.
Equipment available.
Etching
Simple and effective
process.
High energy demand for
some processes because
of high temperatures.
Recovery of high purity
materials
Use of chemical.
Adapted from Chowdhury et al., 2020.
* Current silicon wafers are so thin that cell or wafer recovery may be economical.
Table 9. Typical Recycling Process for Thin Film Solar Modules
Technology
Process
Advantages
Disadvantages
Delamination
Physical disintegration
Feasible to obtain various
wastes by treatment (split
modules, submodules and
laminated modules)
Mixing of the various
material fractions
Loss from each material
fraction
Glass still partly combined
with the EVA
Breakage of solar cells
Thinner dissolution
Organic layer removed from
glass
Time necessary for
delamination depends on
area
Reprocessing solutions
Cannot be dissolved fully
and EVA stiil adheres to
glass surface
Simple removal of EVA
Thermal treatment
Complete elimination of EVA
High energy consumption
Possible to recover whole cell
by reusing wafers
Hazardous emissions
Radiotherapy
Easy to eliminate EVA
Slow procedure
Very expensive process
Material
Separation
Erosion
No chemicals required
Additional treatment of
pre-purification is
necessary
Glass can be recovered
Vacuum blasting
Removal of semiconductor
layer without chemical
dissolution
Emission of metallic
fractions
Glass can be recovered
Relatively long processing
time
Non-chemical process
27
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Sustainable End-of-Life Management of PV-Panels
Technology
Process
Advantages
Disadvantages
Dry arid wet
mechanical process.
Simple procedure
Needs low energy
Apparatus usually available
No removal of dissolved
solids
I&C&idt chemistry
Ign&idg&are reusable
Emulsions must be
adapted to different cell
technologies
Metals fully removed from
glass
Delamination time
depends on the area
Leaching
Complete elimination of metal
from glass
Very high use of chemicals
Further extraction of metal
solutions possible
Complicated control of the
chemical reactions
Flotation
Comparatively easy method
Material separated at
various stages of flotation
Limited use of chemicals
Inadequate purity of
materials
Etching
Recovery of high purity
materials
High energy demand
because of high
temperatures
Low cost and effective
process
Chemical usage
Material
purification
Hydrometallurgical
Commercially applicable
Many separation and
absorption steps
Low and controllable
emissions
Easy water management
Chemical process steps
must be adapted to
respective technology
Pyrometallurgical
Established industrial process
High throughput necessary
Feedstock can contain
different materials
Some materials are lost in
slag
Heavy metals or unwanted
materials
Adapted from Chowdhury et al., 2020.
Waste By-Products from the Recycling Process
A brief literature review of life cycle assessments (LCA) focusing on EoL panel recycling was conducted.
A handful of LCA studies were identified and reviewed with the objective of identifying the type of
waste by-products generated from the recycling process, their amounts, and how these by-products were
managed.
Regarding the outputs of the recycling processes for c-Si and CdTe PV panels, yield for glass and
nonferrous metal for c-Si PV is 59-75% and 13.5-21.8%, respectively, and yield for glass, semiconductor,
and copper in CdTe PV recycling is over 90% (Frischknecht et al., 2020).
Latunussa et al. (2016) was the only study identified that specifically quantified the waste by-products
generated and their ultimate disposition. Figure 17 presents the study's LCA boundary for c-Si PV
recycling and Table 10 presents the inputs and outputs in tabular format for the c-Si PV panel. Waste sent
to a landfill includes 14 kg of contaminated glass, 2 kg of fly ash (hazardous), 306 kg of liquid waste, 50
28
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Sustainable End-of-Life Management of PV-Panels
kg of sludge (hazardous). The fly ash and sludge were the only waste by-products requiring special
(hazardous) waste disposal.
Diewi Fi»l
Electricity
( PVwW )
1000 kt
(1| PVwMte Transport
teion^)
42)
_533
kWh
jnot
kWh
3.2
-kWH-
-»C Emission")
10kgofcatfe(#L
43) Disassembly
(4) Cable
treatment
6.7 kg of
" Polymer H~
iSllrtcincrjtion
Energy Recovery
-»< Emission )
—3 3 kg of copper
BIO kg
lflO kg of Aluminum
> AJgmirtum scrap
!6J Glass
separation
700 kg
-------
Sustainable End-of-Life Management of PV-Panels
Category
Output
Quantity
Units
Notes
Waste to
Landfill
Fly ash
2
-
Hazardous, disposal in hazardous
waste landfill
Waste to
Landfill
Liquid waste
306.13
-
Disposal in landfill
Waste to
Landfill
Sludge
50.25
-
Hazardous, contains metallic residue,
disposal in hazardous waste landfill
4.6 Disposal
Anecdotally, many sources report that broken or damaged panels are being landfilled rather than recycled
because of challenges faced by the recycling sector (e.g., high transportation and dismantling costs);
however, no estimates are available on the amount of solar PV panels currently being disposed in
municipal waste, industrial waste, or hazardous waste landfills. Refer to Section 4.1 Waste Classification
for more information on how a PV panel is classified as hazardous waste if applicable. For any material
classified as a hazardous waste and destined for landfill disposal must be disposed in a hazardous waste
landfill.
5. State Legislation and Working Groups Leading on Sustainable
EoL Management
State legislation, policies, and programs may act as drivers or barriers to sustainable EoL management.
Policy is critical to a circular economy, especially for PV equipment, to ensure its safe handling, storage,
transport, reuse, recycling, and disposal. As discussed in Section 4.1 (Waste Classification), federal and
state solid waste regulations exist that need to be navigated. This is also the case for PV repair and reuse.
Interconnection fire, building, and electric regulations in the U.S. may also vary by jurisdiction and may
prohibit the reuse of PV modules in certain secondary grid-tied and off-grid applications (NREL, 2021).
Variable regulations also exist for recycling and materials recovery of PV system materials in terms of
storage, transport, and handling.
As of June 2021, four states have enacted legislation to address PV system decommissioning, PV
equipment reuse, and/or EoL management for PV system equipment - California, New Jersey, North
Carolina, and Washington. California, Hawaii, and Rhode Island also proposed bills in the past year that
would directly address repair, reuse, and recycling of PV equipment. Figure 17 presents states with
enacted and currently proposed legislation. Several other states proposed bills that were not enacted in
past years - Maryland, New Jersey, and New York. In addition to the state legislation, state-led working
groups in California, Illinois, and Minnesota are researching solar equipment reuse and EoL options.
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Sustainable End-of-Life Management of PV-Panels
Figure 18. Location of States with Enacted and Proposed Legislation Focusing on Solar PV Panel
EoL Management
Note: California has both enacted and proposed legislation (as of June 2021).
5.1 State Legislation
Enacted Legislation
California
In September 2020, the Department of Toxic Substances of California (DTSC) enacted regulation R-
2017-04 to add EoL PV modules to the State Universal Waste regulations with the intent of encouraging
proper waste disposal, a reduction in waste abandonment, and cost savings for PV module waste
generators. These panels would then be subject to less stringent hazardous waste regulations. Specifically,
the DSTC regulations:
¦ Clarify that a PV module becomes waste on the date it is discarded, and that PV modules
abandoned, relinquished, or recycled become waste when they are disconnected or removed from
service.
¦ Clarify PV modules that are refurbished or reused are not waste and are not subject to universal
waste regulations.
¦ Require a party who claims a PV module is not waste bears the burden of demonstrating that
there is a known market or disposition for its use as a PV module.
¦ Establish universal waste requirements for universal waste handlers and universal waste
transporters of PV modules that exhibit toxicity characteristics of hazardous waste.
¦ Specify the management standards for different levels of treatment to ensure treatment is
performed safely.
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Sustainable End-of-Life Management of PV-Panels
Additional requirements not noted in this report are included in the regulation for universal waste
handlers and transporters.
New Jersey
In August 2019, Senate Bill 601 was passed, creating the New Jersey Solar Panel Recycling
Commission. The Commission is tasked with investigating EoL management options for solar energy
generation systems and developing recommendations for legislative, administrative, and private-sector
action. A final report will be submitted to the Governor for consideration by August 2021. The Bill also
authorizes the New Jersey Department of Environmental Protection to adopt rules and regulations
regarding EoL PV recycling or management options based on the Commission's final report.
North Carolina
House Bill 329 was passed in the 2019 General Session, requiring the North Carolina Environmental
Management Commission (EMC) of the North Carolina Department of Environmental Quality (NCDEQ)
to establish a regulatory program to "require the environmental management commission to adopt rules to
establish a regulatory program to govern the management of end-of-life photovoltaic modules and energy
storage system batteries, and decommissioning of utility-scale solar projects and wind energy facilities,
and require the Department of Environmental Quality to establish a stakeholder process to support
development of the rules."
Under the bill, the NC EMC must develop the program by January 1, 2022, including regulations and a
system of implementation and enforcement. The NCDEQ must consider explicit issues stated in the bill:
¦ Whether PV modules are properly characterized as solid waste under state and federal law
¦ Whether PV modules exhibit hazardous waste characteristics or contain any constituent of
hazardous waste
¦ The preferred methods of end-of-life management (i.e., reuse, recycled, refurbish, or disposal)
¦ The economic and environmental cost and benefits
¦ An evidence-based economically productive life cycle
¦ The volume of PV panels and batteries deployed in the state, projected PV deployment, and the
impact that volume would have on state landfills if landfill disposal were permitted
¦ Other federal, state, and international regulatory requirements related to EoL PV modules and
solar equipment management, decommissioning, reuse, refurbishment, recycling and disposal
¦ Whether financial assurance requirements are necessary
¦ The infrastructure necessary to collect and transport EoL PV panels and other solar equipment for
EoL management, and
¦ Whether to construct a stewardship program for recycling EoL panels other than utility-scale
solar projects, and if so, what fees should be established for manufacturers to sell PV modules in
the state.
On January 1, 2021, the NCDEQ issued a final report on the Commission's findings, which may be used
in the development of future regulations.
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Sustainable End-of-Life Management of PV-Panels
Washington
The Washington State Senate passed Bill 5939 on July 7, 2017, with the intent of stimulating and
investing in distributed renewable energy generation (i.e., wind, solar, microgrid) to reduce the state's
reliance on fossil fuel energy. Bill 5939 has no recycling or disposal requirements but is a companion bill
to HB 2645 (passed March 2020) concerning the Photovoltaic Module Stewardship and Takeback
Program, which requires PV module manufacturers to finance and implement a takeback and recycling or
reuse stewardship plan for PV modules sold after July 1, 2017 at no cost to owners. Tax credits and
incentives are also provided. The overall goal of this legislation is to establish an environmentally sound
system for recycling PV modules, minimizing hazardous waste and recovering valuable materials during
this process.
Beginning July 1, 2023, no manufacturer, distributor, retailer, or installer may sell or offer for sale PV
modules within or into Washington unless the manufacturer of the PV module has submitted a
stewardship plan to the Department of Ecology (by July 2022) and obtained approval. The intent of the
stewardship plan is to develop a framework for how manufacturers will fund the manufacturer takeback
program, collection, management, and recycling of the PV modules. The PV modules under the program
include the following:
¦ PV modules used for residential, commercial, agricultural, or utility purposes that are installed
on, connected to, or integral with buildings, or are a part of a system connected to the grid or
utility service; and
¦ Freestanding, off-grid power generation systems.
The responsibility for the PV waste management would be on the manufacturer, giving the customer a
viable way to return and recycle spent or damaged PV modules. The plan would also provide the
manufacturer or installer a viable path to sell their systems and/or services, thereby introducing financial
stability. The Washington state program will also require the minimization of the release of hazardous
substances and the recovery of rare earth metals similar to California Senate Bill 489.
As part of the takeback program, the Department of Ecology may collect a flat fee from every
participating manufacturer to cover the administration costs and an annual fee from each manufacturer
based on the manufacturer's pro rata share of the preceding year's PV module sales in Washington. Non-
compliance fees up to $10,000 per sale of a PV module are also included in the legislation and will be
used for administration costs.
Proposed Legislation
California
Senate Bill 207, introduced January 1, 2021, would require the state's Secretary for Environmental
Protection to convene a Photovoltaic Recycling Advisory Group to study and recommend potential
policies to the state legislature to ensure safe and cost-effective reuse or recycling of PV modules in
California. The Group's recommendations are to be submitted to the legislature no later than April 1,
2025.
Hawaii
House Bill 1333 was introduced January 27, 2021, and would require the Hawaii State Energy Office to
work with the Hawaii State Department of Health on a comprehensive study to determine best practices
for disposing of and recycling discarded clean energy products such as PV modules and equipment, and
batteries. The study is investigating similar topics to the NC law related to projected EoL solar waste
33
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Sustainable End-of-Life Management of PV-Panels
Hawaii may need to manage, the type and chemical composition of clean energy equipment, best
practices for EoL management, and whether a fee structure should be developed for disposal or recycling
of clean energy materials. An interim report is to be submitted in 2022 followed by a final report in 2023.
Rhode Island
House Bill 5525, introduced February 12, 2021, would create a Photovoltaic Module Stewardship and
Takeback Program requiring PV module manufacturers to finance and implement a takeback and
recycling or reuse plan for PV modules sold in or into Rhode Island after July 1, 2021, at no cost to
owners. The Bill specifies that the Department of Environmental Management must develop and
implement guidance to aid manufacturers in preparing and implementing self-directed stewardship plans
by July 1, 2022. No manufacturer, distributor, retailer, or installer would be able to sell of offer PV
modules for sale within or into Rhode Island beginning July 1, 2023, unless the manufacturer or the PV
module had submitted a stewardship plan to the Rhode Island Department of Environmental Management
and obtained approval. The potential requirements of the Bill are similar to Washington's legislation.
5.2 State Working Groups
Working groups in California, Illinois, and Minnesota are working on various initiatives to build initiative
and collaboration around sustainable EoL management for PV modules.
In California, the California Public Utilities Commission (CPUC); the California Department of
Resources Recycling and Recovery (CalRecycle); the California Air Resources Board (CARB), and the
California Energy Commission (CEC) are collaborating to develop consistent approaches to the collection
and recycling of solar PV panels, electric vehicle batteries, energy storage batteries, and related
equipment.
The Illinois Sustainable Technology Center (ISTC) at the University of Illinois created the Solar Panel
Recycling Initiative in 2019 in response to the Illinois Future Jobs Act of 2016. ISTC is working with the
Illinois Environmental Protection Agency to facilitate the PV EOL management stakeholder working
group to identify and evaluate barriers to integrating PV into the circular economy and develop solutions
to promote sustainable management options.
In Minnesota, the Minnesota Pollution Control Agency (MPCA) started a stakeholder working group
along with the Minnesota Department of Commerce and Minnesota SEIA. The intent of the group is to
develop and implement PV panel EoL policy and programs that conserve resources, protect health,
promote renewable energy, and support PV panel recycling infrastructure and technology.
6. Current U.S. Recycling Market
This section compiles current data on recycling facilities that process solar PV panels and equipment in
the U.S. (Section 6.1) and internationally (Section 6.2). Section 6.3 synthesizes findings on drivers,
barriers, and enabling factors to a circular economy with specific focus on the recycling and reuse
(secondary market) components of the value chain.
6.1 PV Panel Recycling Facilities in the U.S.
More than 20 facilities recycling solar PV panels and/or equipment, or just components of solar panels
(e.g., glass, aluminum frames) have been identified in the U.S. as presented in Figure 18 and Table 10.
34
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Sustainable End-of-Life Management of PV-Panels
The identified recycling facilities were primarily sourced from two leading databases - the SEIA's PV
Recycling Partner Network (available for members only) and the ENF Solar Recycling Database. Table
10 specifically does not include scrap metal processing facilities that presumably would accept aluminum
frames from EoL solar PV panels because these facilities tend not to advertise the types of products (e.g.
solar panels) that scrap metal comes from on their websites.
The top 10 solar electricity generating states in 2021 are California, Texas, North Carolina, Florida,
Arizona, Nevada, New Jersey, New York, Nevada, North Carolina, Massachusetts, New York, and
Georgia (SEIA 2021; AEO 2020 Projected Growth). Nearly all of these states except New Jersey, New
York, North Carolina, and Massachusetts have at least one solar panel recycling facilities located there.
Surprisingly, no dedicated solar panel recycling facilities were identified through internet searches in
some states that have enacted or recently proposed solar panel EOL-related legislation (i.e., Washington,
Hawaii, Rhode Island, and North Carolina). EoL PV panels generated in these states would presumably
be transported to another state for processing.
0 Recycling facility
that processes
solar panels
and/or equipment
Hawaii
Puerto Rico
Figure 19. Locations of Known Solar Panel Recycling Facilities in the U.S.
Note: Recycling facilities included in this map are listed in Table 10, which may not include all facilities in the U.S.
that recycling solar PV panels.
C-Si PV modules are mainly treated in recycling facilities designed for the treatment of laminated glass,
metals, or other electronic waste, and only the bulk materials (glass, aluminum, and copper) are
recovered. In contrast, the cells and other materials such as plastics are incinerated (Frischknecht et al.,
2020). Only two companies identified were found to recover the high-purity bulk and trace materials from
PV modules - We Recycle Solar and First Solar.
We Recycle Solar based in Phoenix, Arizona, has a provisional patent technology that can process up to
100,000 pounds of solar equipment per day of c-Si and CdTe modules in each of their 10 facilities across
the U.S., Japan, South Korea, and Belgium. The company's current focus is on large-scale recycling best
suited for sourcing from manufacturers, utilities, or installers, rather than individual customers. We
35
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Sustainable End-of-Life Management of PV-Panels
Recycle Solar recycles all related equipment, including batteries, which streamlines the disposal process
and helps companies meet any end-of-life requirements from local or state authorities. Although larger
volume materials, such as Al, and Cu are commonly recovered, the information on the recovery of trace
materials is lacking.
First Solar has a unique value proposition, which combines manufacturing, sales, and recycling. The
First Solar recycling process can recover approximately 90 percent of panel glass and semiconductor
materials (only from CdTe panels) for reuse. The company also implemented an EoL fee. This fee was
originally included in the upfront cost for their PV panels but was to a pay at decommissioning model in
2013. There is potential for other solar panel manufacturers to enter into the recycling space in the near-
term, particularly if states in addition to Washington implement manufacturer take-back programs.
Table 11. Solar Equipment Recycling Facilities in the U.S.
Company Name
Location
Solar Recycling
Services
Type of Solar
Products
Recycled1
CEM
¦ Okmolgee, OK
¦ Waxahachie, TX
¦ Lawrenceburg, KY
¦ Upper Sandusky, OH
¦ Yuma, AZ
¦ Natrona Heights, PA
¦ Hardeeville, SC
¦ Portland, OR (coming
soon, glass processing
only)
¦ Drop-off
¦ Transfer station
¦ Drop-off
¦ Processing
¦ Drop-off
¦ Drop-off
¦ Drop-off
¦ Processing
Solar Panels,
Glass
Cleanlites
Recycling
¦ Cincinnati, OH
¦ Spartanburg, SC
¦ Mason, Ml
¦ Minneapolis, MN
¦ Recycling and Drop-off
Solar Panels
Dynamic Lifecycle
Innovations
¦ Minneapolis, MN
¦ Onalaska, Wl
¦ Nashville, TN
¦ Recycling
Solar Panels,
Cable, Junction
Box, Frame
Echo
Environmental
¦ Carrollton, TX
¦ Recycling
Solar Panels
FabTech
¦ Gilbert, AZ
¦ Savannah, GA
¦ Recycling
Solar Panels
First Solar
¦ Tempe,AZ
(headquarters)
¦ Recycling
Solar Panels
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Sustainable End-of-Life Management of PV-Panels
Company Name
Location
Solar Recycling
Services
Type of Solar
Products
Recycled1
Green Lights
Recycling
¦ Blaine, MN
¦ Recycling
Solar Panels
Interco - A
Metaltronics
Recycler
¦ Madison, IL
¦ Recycling
Solar Panels
Metal & Catalyst
Resources
¦ Houston, TX
¦ Recycling
Chemical
Elements
Mitsubishi Electric
¦ Cypress, CA
¦ Recycling
Solar Panels
Recycle PV Solar
¦ South Lake Tahoe, NV
¦ Recycling
Solar Panels
Recycle1234
¦ Union City, CA
¦ Recycling
¦ Drop-off
¦ Reuse
Solar Panels
Solar Silicon
¦ Ventura, CA
¦ Recycling
Wafer
Silrec
¦ Lexington, KY
¦ Recycling
Ingot, Wafer
Solar Recycling
Experts
¦ Tehachapi, CA
¦ Recycling
Solar Panels
Solar Sun's
Recycling
¦ Orlando, FL
¦ Recycling
Cell, Solar Panels
Surplus Service
¦ Fremont, CA
¦ Recycling
Solar Panels
TT&E Iron & Metal
Inc.2
¦ Raleigh, NC
¦ Drop-off
¦ Recycling
Aluminum frames
We Recycle Solar
¦ Phoenix, AZ
¦ Recycling
Cell, Solar
Panels, Chemical
Elements, All
Related
Equipment
Source: ENF Solar, n.d.
1 Companies included in this table may recycle other products and materials that are not solar equipment.
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Sustainable End-of-Life Management of PV-Panels
2 This is a scrap metal processing facility. A dedicated search for scrap metal processing facilities that accept solar
panels was not undertaken. Most company websites do not specifically mention solar waste processing as a service,
but they would likely accept the aluminum frames.
6.2 International PV Recycling Facilities
For general information, a list of recycling facilities in select international countries are presented in
Table 11. These companies could open a location in the U.S. in the future, or panels from the U.S. could
be exported to one of these international locations for recycling. China would likely a potential
destination for U.S. EoL PV panels if they are not already being exported for processing and recovery.
Table 12. Solar Recycling Companies in Select International Locations
Country
Company Name
Australia
Cyber Computer Recycling & Disposal
E3Sixty Solar
Infoactiv
Ojas Infrastructure
PV Industries
Reclaim PV Recycling
Germany
Aurubis
Envaris
Reiling Glas Recycling
Rieger & Kraft Solar
SiC Processing (Deutschland)
United Kingdom
H&H Pro
ILM Highland
Recycle Solar Technologies
Solar2Recycle
Japan
Eiki Shoji
NPC Inc.
Okaishi Construction
Trinity
China
Bocai E-energy
Chaoqiang Silicon Material
FH Solar
Jiangsu Juxin Energy Silicon Technology
Kunshan Suda Jingwei Electronic Technology
Suzhou Hedeying Metal
Suzhou Huizhijie PV Technology
Suzhou Minlai Photovoltaic New Energy
Suzhou Shunhui New Energy Technology
Yezon-PV
India
Jumbo Solar
Poseidon Solar Services
Source: ENFSolar, n.d.
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Sustainable End-of-Life Management of PV-Panels
6.3 Drivers, Barriers, and Enablers to a Circular Economy
Several drivers, barriers, and enablers related to sustainable PV panel EoL management exist at
the national level.
Drivers are opportunities that motivate actors to adopt a desired behavior and typically benefit
specific stakeholders or the public interest. Federal, state, and industry policy can either enable
or inhibit a particular opportunity or benefit. Economic and environmental drivers are presented
in Table 12.
Barriers are factors that may hinder a desired behavior or outcome. Federal, state, and industry
policy can inhibit a particular opportunity, benefit, or desired outcome. Identifying the major
barriers associated with PV module recycling may help policymakers formulate policy solutions
to overcome future challenges. A variety of barriers are presented in Table 13.
Enablers are solutions or ways to overcome a barrier that inhibits a desired behavior or outcome.
Federal, state, and industry policy can enable a desired behavior or outcome. The main enablers
are presented in Table 14.
The main stakeholders who may be impacted are identified for each driver, barrier, and enabler.
The stakeholder groups include manufacturers, installers, PV owners, operation and maintenance
(O&M) service providers, companies managing solar logistics and EoL PV panel waste haulers,
recycling companies, the government (local, state, federal), end users of recycled materials, and
landfill owners and operators.
In summary, the barriers currently outweigh the drivers and enablers at the national level and
most likely at every state level too, although a deep dive into each state's market was not
performed. The cost to recycle EoL solar panels tends to be cost-prohibitive largely because
there is not enough volume to achieve economies of scale currently. This will likely change in
the next 10 to 20 years given EoL PV panel projection estimates. Most recycling companies
currently focus on recovery of the aluminum frames and panel glass; only two companies - We
Recycle Solar and First Solar - are recovering the other valuable materials that make up less than
10 percent total of a PV panel. One potential uncertainty in the future recycling market is
changing technology and panel materials. Silver is the most valuable material per unit mass in
the c-Si module followed by aluminum (Holm & Martin, 2020); however, if less silver is used in
future module design to reduce manufacturing costs, that will decrease the value of the modules
for recycling. Another question still to be answered is who will pay for EoL management,
specifically recycling, of PV panels. Manufacturer take-back programs are scarce, but this may
change if recently enacted legislation in Washington is successful. Based on an NREL analysis
(Curtis et al., 2021a), a multifaceted regulatory approach that places responsibility across the
value chain is recommended. Consistent, clearly defined federal, state, and local regulations
could mandate and incentivize recycling and secondary markets. These laws could prohibit
disposing PV modules, provide an exemption from stringent regulation, or require reuse.
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Sustainable End-of-Life Management of PV-Panels
Table 13. Drivers to a Circular Economy for PV System Materials and Stakeholders Who May Be Impacted
Driver
Description
Manufacturer
Installer
PV Owner
O&M Provider
Logistics,
Hauler
Recycler
Government
End User
Landfill
Operator
Cost savings and increased
profits
May reduce manufacturing costs and
achieve additional revenue streams;
may decrease project costs.
X
-
X
X
-
-
-
X
-
Enhanced competitiveness
May increase a business's green or
environmentally responsible image and
ncrease consumer trust.
X
X
X
X
-
-
-
X
-
New and expanded market
and employment opportunities
Provide opportunities for new and
expanded markets and job creation.
X
X
X
X
-
X
X
-
-
Reduced negative
environmental impacts
Reduces waste, the generation of
greenhouse gases and other air
Dollutants, and electricity consumption
during manufacturing and additional
resource use and environmental
mpacts from mining raw materials,
transport, refining, and manufacturing
of products .
X
X
X
X
-
X
X
-
-
Reduced resource constraints
Conserve high-value materials,
prevent resource constraints, and
reduce import demand for raw
materials.
X
-
-
-
-
-
X
-
-
vfote: Adapted from Curtis et a
[.,2021
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Sustainable End-of-Life Management of PV-Panels
Table 14. Barriers to a Circular Economy for PV System Materials and Stakeholders Who May Be Impacted
Barrier
Description
1—
o
1—
a.
oa
o
Logistics,
Hauler
Recycler
Govern men
End User
Landfill
Operator
Lack of support for research,
development, and analysis
Limited policies exist to fund research, development, and analysis
for the:
¦ valuation of and markets for recovered PV materials;
¦ volume and composition of EoL PV systems;
¦ development of PV module recycling technology and
assessment of infrastructure needs;
¦ identification and analysis of permitting requirements and
liabilities; and
¦ costs associated with PV module recycling.
X
X
X
X
X
X
X
"
-
Lack of publicly available
information and exchange
between solar value chain
actors
Company policies do not support information exchange between
manufacturers and recyclers or between end users and landfill
owners and operators.
X
X
X
X
X
X
-
X
X
Lack of economic incentives
Limited economic incentives exist to promote design for recycling
or reuse, or for the collection, transport and repair/reuse/recycling
of EoL PV modules.
X
X
X
X
X
X
-
X
X
Current technology,
infrastructure, and
processes
Current technology, infrastructure, and processes are not optimized
for efficient, cost-effective repair, reuse, or recycling of PV system
equipment.
-
X
X
X
-
X
-
-
-
Lack of critical information
and data
Research and data play an important role in investment decisions
during early stages in new and expanded market opportunities.
Limited information and data are available regarding the:
¦ value of and markets for reused PV equipment and recovered
PV materials;
¦ volume and composition of retired PV equipment;
¦ condition and characteristics of used PV equipment;
¦ quality, reliability, safety, and technical viability of repaired and
reused PV equipment;
¦ repair and recycling technologies, processes, and services; and
¦ costs for repair and refurbishment; and infrastructure needs.
-
X
X
X
X
X
X
X
-
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Sustainable End-of-Life Management of PV-Panels
Barrier
Description
Manufacturer
Installer
PV Owner
O&M Provider
Logistics,
Hauler
Recycler
Government
End User
Landfill
Operator
Unclear, complex, and
varied laws and regulations
at state and local level
Laws and regulations applicable to reuse and recycling of PV
equipment may be unclear, complex, varied by jurisdiction, and
often require compliance with stringent handling, storage, transport,
treatment, recycling and disposal requirements that are subject to
civil and criminal liability for non-compliance.
X
X
X
X
X
X
X
X
X
Existing statutory and
regulatory schemes do not
support recycling and
resource recovery
No federal and limited state policies exist to mandate or incentivize
PV module recycling; the current statutory and regulatory scheme
often mandates compliance with stringent handling, storage,
transport, treatment, recycling, and disposal requirements that
carry civil and criminal liability for non-compliance.
X
X
X
X
X
X
X
X
X
Low market confidence in
reused and repaired PV
equipment
Inadequate consumer confidence in reused and repaired PV
system equipment to support reuse and repair for reuse secondary
markets.
X
X
X
X
-
-
-
-
-
Note: Adapted from Curtis et al., 2021a
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Sustainable End-of-Life Management of PV-Panels
Table 15. Enablers to a Circular Economy for PV System Materials and Stakeholders Who May Be Impacted
Enabler
Description
Manufacturer
Installer
PV Owner
O&M Provider
Logistics,
Hauler
Recycler
Government
End User
Landfill
Operator
Increasing investment in
research and development,
and analysis
Several factors could reduce market
uncertainty and investment risk, and
increase consumer confidence towards
reused and repaired PV panels,
including for the:
¦ value of and markets for recovered
PV module materials;
¦ volume and composition of EoL PV
modules;
¦ PV module recycling technology
development and infrastructure
needs;
¦ permitting requirements and
liabilities; and
¦ costs associated with PV module
recycling.
X
X
X
X
X
X
X
X
-
Increased and publicly
available information and
information exchange
Information exchange between
manufacturers and recyclers, and
between end users and landfill owners
and operators, can reduce costs,
liability uncertainties and increase
good faith relationships between solar
industry stakeholders.
X
X
X
X
X
X
X
X
X
Increased economic
incentives
Economic incentives may be provided
to promote design for recycling and/or
collection + recycling can encourage
innovation, private industry investment,
and make the economics for PV
module recycling more desirable.
X
X
X
X
X
X
X
X
X
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Sustainable End-of-Life Management of PV-Panels
Enabler
Description
Manufacturer
Installer
PV Owner
O&M Provider
Logistics,
Hauler
Recycler
Government
End User
Landfill
Operator
Collaboratively developed
industry initiatives, standards,
and goals
Global and national voluntary industry
nitiatives (e.g., SEIA's national PV
recycling program), standards (e.g.,
NSF 457) and goals (e.g., resource
recovery) can encourage
environmentally sustainable business
practices. When collaboratively
developed, there may be more buy-in
across stakeholders and a broader
push to increase recycling and reuse.
X
-
X
X
-
-
X
-
-
Clearly defined laws and
regulations
Clearly defined regulatory
requirements and restrictions can
reduce uncertainty and risk associated
with PV module recycling and resource
recovery.
X
X
X
X
X
X
X
X
-
Statutory and regulatory
schemes that support PV
module recycling and
resource recovery efforts
Federal and state policies can require
or incentivize the collection, repair,
reuse, and/or recycling of PV modules
and/or restrict disposal of PV modules.
X
X
X
X
X
X
X
X
-
vfote: Adapted from Curtis et a
1., 2021a and 2021b
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Sustainable End-of-Life Management of PV-Panels
7. Future Research Recommendations
By 2050, there may be 7.9 million (early loss scenario) to 9.1 million metric tons (regular loss scenario)
of EoL PV panels entering the waste stream nationally based on the methodology and assumptions
discussed in Section 3. While state-specific estimates vary based on current and projected installed PV
capacity, it is clear that some states will be more burdened than others. Despite the number of barriers
presented in Section 6, the status of the solar recycling and reuse market in the U.S. remains promising.
Grandview Research's 2020 summary report2, for example, estimates a market size value of $160.8
million in 2020, a revenue forecast of $338.8 million in 2027, and a growth rate of 12.8 percent from
2020 to 2027 (Grandview Research, 2020). Recently enacted state legislation, specifically in Region 9
and 10, and the federal government's push to increase solar electricity generating capacity are also
promising drivers to move towards a more circular economy.
Potential future research activities to refine the PV panel EoL projection estimates, and advance
sustainable EoL management options are summarized below.
¦ Targeted research and data collection on:
o The secondary market and best practices for collection and repair
o A proper protocol for recertification of reuse panels
o The off-grid market and small-scale solar (e.g., landscape lighting, solar-powered
cooking stoves, etc.)
o Best practices for solar takeback programs
o Develop a solar panel specific TCLP procedure with defined encapsulant conditions
¦ Comprehensive review and policy assessment specific to the solar secondary market by state to
further understand which states may be prohibitive to panel reuse
¦ Compile case studies on panel reuse in U.S. territories, indigenous lands, and in low-income
households
¦ EoL model refinements:
o Improve on static assumptions used in the calculations for market share over time
o Consider alternative Loss scenarios that modulate the t value (average life expectancy)
and alpha parameter
o Investigate solar installation in Puerto Rico and U.S. territories and estimate potential
EoL panel material
o User improvements, such as automating the regional selection when selecting a state in
the INOUT worksheet, adding a filterable results tab with sort by state.
¦ Regulatory guidelines and enforcement are needed to prevent lead from getting into the
environment from the material recovery and end-of-life management practices
2 Only the free summary version of Grandview Research (2020) was reviewed for this report.
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Sustainable End-of-Life Management of PV-Panels
8. Conclusion
Growing PV panel waste presents a new environmental challenge and unprecedented opportunities to
create value and pursue new economic avenues. Untill recenlty, more than 80% of PV panels installed
across the world were crystalline-Si panels. Typically, more than 90% of their mass is composed of glass,
polymer and aluminum, which can be classified as nonhazardous waste. However, smaller constituents of
c-Si panels can present recycling difficulties since they contain silicon, silver, and traces of elements such
as tin and lead (together accounting for around 4% of the mass). Thinfilm panels (9% of global annual
production) consist of more than 98% glass, polymer and aluminium (nonhazardous waste) but also
modest amounts of copper and zinc (together around 2% of the mass), which is potentially
environmentally hazardous waste. They also contain semiconductor or hazardous materials such as
indium, gallium, selenium, cadmium tellurium and lead. Hazardous materials need particular treatment
and may fall under a specific waste classification depending on the jurisdiction. Since end-of-life PV
panels are not listed as hazardous waste, they should be evaluated using the characteristic hazardous
waste method (US Environmental Protection Agency Method 1311 Toxicity Characteristic Leaching
Procedure). No federal regulations currently exist in the US for collecting and recycling end-of-life PV
panels, and therefore the country's general waste regulations apply. California is developing a regulation
for the management of end-of-life PV panels within its borders, though several steps remain before this
regulation is implemented.
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Sustainable End-of-Life Management of PV-Panels
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Sustainable End-of-Life Management of PV-Panels
Appendix A - EoL Projections Model Documentation
Table A-l. PV EoL Model Worksheets and Description
Type
Sheet Name
Description
Data Sources
Results
INOUT
Provides an interface for Users. Users select the
region or state of interest using a drop down box.
Model results, tables, and figures are presented at
right.
Summarized view of
data in other
worksheets.
Results
PivotState
Pivot table summarizing the PV EoL data by state
and scenario in million pounds and metric tons.
RTI calculated using
data from the
PVEOLWeight
worksheet.
Results
PivotRegion
Pivot table summarizing the PV EoL data by state
and scenario in million pounds and metric tons.
RTI calculated using
data from the
PVEOLWeight
worksheet.
Intermediate
Worksheets
PVEOLW eight
This sheet multiplies the unit sales by the average
product weight listed on the INOUT sheet.
Provides results (national, state, regional) by
scenario of the weight of PV panels in million
pounds by consumer segment, year.
RTI calculated using
data from the
PVPanelsSold
worksheet, Lifetimes
worksheet, and the
weights presented on
the INOUT worksheet.
Intermediate
Worksheets
PVPanelsSold
This sheet converts the incremental installed
capacity to the equivalent number of PV panels by
state and panel type. It pulls information from
Market Share and PV_CapIncremental sheets.
Data table breaks out regional sales to one of the
four consumer segments: residential, commercial,
institutional, and education.
RTI calculated using
data from other
worksheets.
Intermediate
Worksheets
PVC aplncremental
Data table incremental installed PV capacity by
state by year (2010 to 2050).
This sheet decomposes the total installed capacity
from PV_Capacity sheet for years 2010 through
2050. For years 2010 to 2020, we use the national
incremental capacity percentages to back cast the
time-series of incremental capacity additions from
the SEIA data for total installed capacity in 2020.
RTI calculated.
50
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Sustainable End-of-Life Management of PV-Panels
Type
Sheet Name
Description
Data Sources
Intermediate
Worksheets
PVCapacity
Data table of installed solar PV capacity by state
between 2020 and 2050. Total Capacity expressed
in megawatts (MW).
2020 as of Q4 - Solar
Energy Industries
Association (SEIA),
Capacity by U.S. State
2020 Annual Energy
Outlook (AEO) -
Annual grow rate in
installed solar PV
capacity 6.8% for
years 2025-2050.
Input Data
MarketShare
Data table provides state market share allocation
by consumer segment and product type.
2019 -EIA-861, Net
Metering
2019 - EIA-861, Non-
Net Metering
Distributed
2019 - EIA-860
Existing Capacity by
State
Input Data
Lifetimes
Calculates the percentage of installed capacity that
is retired to End of Life Management (ELM) for
recycling and/or disposal.
Weibull parameters for
early loss and regular
loss from IRENA,
2016.
Input Data
LookUps
Provides lists of state names and state region
assignments.
Not applicable.
51
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Sustainable End-of-Life Management of PV-Panels
Appendix B - EoL Projections by State
Tables B-l, B-2, and B-3 present EoL projection data (metric tons) by state in 5-year increments from
2015 to 2050 for the early loss, mid loss, and regular loss scenarios, respectively. Data are presented
alphabetically by state.
Table B-l. EoL Mass of Solar PV Estimates and Projections, 5-year increments, 2015 to 2050
(metric tons) for the Early Loss (EL) Scenario by State
State
Scenario
2015
2020
2025
2030
2035
2040
2045
2050
National
EL
6,834
131,051
506,311
1,281,707
2,544,631
4,212,169
6,302,028
9,087,051
AK
EL
1
14
58
179
409
731
1,129
1,602
AL
EL
22
419
2,060
10,486
35,275
83,323
166,351
307,340
AR
EL
29
557
2,393
8,103
19,976
37,835
61,610
92,241
AZ
EL
372
7,135
26,683
59,324
99,708
138,248
167,603
184,857
CA
EL
2,255
43,245
160,506
348,930
573,213
778,080
922,936
993,828
CO
EL
119
2,274
9,549
30,230
70,443
127,921
200,451
288,576
CT
EL
63
1,209
4,621
10,954
19,623
28,811
36,984
43,369
DC
EL
8
154
628
1,816
3,914
6,694
9,928
13,514
DE
EL
11
217
919
2,987
7,114
13,133
20,892
30,543
FL
EL
444
8,509
33,644
88,496
175,012
279,413
388,674
495,493
GA
EL
206
3,949
14,821
33,299
56,563
79,191
96,956
108,089
HI
EL
108
2,070
7,940
19,037
34,483
51,120
66,243
78,456
IA
EL
11
220
920
2,878
6,636
11,956
18,600
26,581
ID
EL
44
837
3,134
6,981
11,755
16,328
19,831
21,916
IL
EL
29
554
2,641
12,268
38,629
87,144
166,654
294,414
IN
EL
37
703
3,443
17,324
57,798
135,742
269,546
495,204
KS
EL
6
118
482
1,420
3,107
5,378
8,064
11,101
KY
EL
4
84
472
3,524
15,395
43,558
103,410
229,211
LA
EL
15
281
1,241
4,599
12,197
24,364
41,652
65,541
MA
EL
225
4,308
15,911
34,100
55,205
73,908
86,415
91,573
MD
EL
100
1,915
7,359
17,744
32,317
48,137
62,666
74,581
ME
EL
7
144
813
6,130
26,951
76,593
182,628
406,660
Ml
EL
16
308
1,610
9,738
36,950
94,849
204,911
411,207
MN
EL
116
2,232
8,397
19,004
32,516
45,828
56,486
63,430
MO
EL
22
417
1,796
6,158
15,338
29,268
47,988
72,353
MS
EL
25
471
2,025
6,894
17,070
32,433
52,967
79,536
MT
EL
5
102
504
2,604
8,850
21,056
42,323
78,748
NC
EL
501
9,601
35,378
75,303
121,048
160,965
186,870
196,444
ND
EL
0
1
7
144
605
1,516
3,090
5,755
NE
EL
5
93
416
1,617
4,448
9,124
15,983
25,786
NH
EL
10
183
782
2,610
6,359
11,937
19,281
28,629
52
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Sustainable End-of-Life Management of PV-Panels
State
Scenario
2015
2020
2025
2030
2035
2040
2045
2050
NJ
EL
268
5,138
18,995
40,815
66,251
88,919
104,239
110,785
NM
EL
91
1,739
7,014
19,596
40,946
68,339
99,088
131,802
NV
EL
281
5,393
21,087
53,599
102,662
159,619
216,540
269,010
NY
EL
192
3,674
15,005
43,571
94,225
161,581
240,225
327,802
OH
EL
28
534
2,520
11,359
34,983
77,709
146,488
254,954
OK
EL
5
101
528
3,231
12,355
31,889
69,252
139,736
OR
EL
71
1,355
5,304
13,529
26,000
40,539
55,143
68,695
PA
EL
51
983
3,943
10,832
22,290
36,752
52,687
69,273
Rl
EL
27
520
1,960
4,466
7,695
10,913
13,535
15,302
SC
EL
133
2,542
9,604
22,013
38,144
54,377
67,794
77,071
SD
EL
0
3
40
1,104
4,758
11,986
24,493
45,641
TN
EL
27
520
2,461
11,206
34,780
77,674
147,157
257,450
TX
EL
521
9,993
41,671
129,065
295,196
528,543
817,578
1,161,619
UT
EL
146
2,796
10,549
24,085
41,574
59,061
73,381
83,113
VA
EL
103
1,984
8,298
25,923
59,728
107,542
167,205
238,808
VT
EL
28
535
2,010
4,523
7,694
10,786
13,224
14,764
WA
EL
18
348
1,487
4,940
11,987
22,438
36,148
53,532
Wl
EL
18
351
1,792
10,136
36,730
91,337
191,434
372,134
WV
EL
1
16
93
795
3,806
11,472
28,989
68,641
WY
EL
11
205
800
2,041
3,919
6,108
8,304
10,339
53
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Sustainable End-of-Life Management of PV-Panels
Table B-2. EoL Mass of Solar PV Estimates and Projections, 5-year increments, 2015 to 2050
(metric tons) for the Mid Loss (ML) Scenario by State
State
Scenario
2015
2020
2025
2030
2035
2040
2045
2050
National
ML
611
25,985
184,222
657,479
1,676,217
3,358,850
5,606,635
8,267,484
AK
ML
0
3
20
80
235
530
966
1,497
AL
ML
2
83
630
3,461
14,870
45,808
109,786
223,046
AR
ML
3
110
807
3,416
10,753
25,812
49,893
81,976
AZ
ML
33
1,415
9,944
33,414
76,548
133,369
185,561
213,575
CA
ML
202
8,575
60,150
199,804
450,251
769,485
1,045,771
1,168,375
CO
ML
11
451
3,271
13,317
39,810
91,218
168,974
266,116
CT
ML
6
240
1,696
5,889
14,147
26,011
38,529
47,816
DC
ML
1
31
220
850
2,371
5,092
8,868
13,122
DE
ML
1
43
313
1,293
3,944
9,203
17,336
27,763
FL
ML
40
1,687
12,042
44,198
114,774
229,350
371,663
509,841
GA
ML
18
783
5,509
18,612
42,969
75,537
106,226
123,894
HI
ML
10
410
2,905
10,151
24,593
45,641
68,318
85,819
IA
ML
1
44
316
1,278
3,785
8,597
15,798
24,681
ID
ML
4
166
1,167
3,926
9,007
15,719
21,914
25,284
IL
ML
3
110
826
4,265
17,095
49,992
114,686
223,088
IN
ML
3
139
1,056
5,755
24,510
75,018
178,818
361,333
KS
ML
1
23
168
656
1,856
4,037
7,120
10,669
KY
ML
0
17
131
952
5,448
20,500
58,138
140,176
LA
ML
1
56
410
1,831
6,177
15,739
32,079
55,541
MA
ML
20
854
5,984
19,733
44,007
74,285
99,422
108,885
MD
ML
9
380
2,689
9,424
22,926
42,745
64,312
81,264
ME
ML
1
28
225
1,649
9,500
35,918
102,280
247,656
Ml
ML
1
61
472
2,927
14,322
48,430
125,501
275,826
MN
ML
10
443
3,116
10,565
24,523
43,377
61,447
72,311
MO
ML
2
83
604
2,576
8,185
19,812
38,586
63,874
MS
ML
2
93
682
2,897
9,156
22,054
42,765
70,487
MT
ML
0
20
154
852
3,703
11,500
27,750
56,764
NC
ML
45
1,904
13,327
43,799
97,189
163,078
216,621
234,891
ND
ML
0
0
1
29
213
775
1,990
4,164
NE
ML
0
18
136
625
2,186
5,739
12,008
21,332
NH
ML
1
36
265
1,111
3,458
8,219
15,746
25,643
NJ
ML
24
1,019
7,139
23,574
52,671
89,110
119,595
131,458
NM
ML
8
345
2,475
9,388
25,516
53,393
90,662
130,663
NV
ML
25
1,069
7,609
27,420
69,392
134,987
212,669
282,951
NY
ML
17
729
5,246
20,332
56,907
122,549
214,039
317,589
OH
ML
2
106
794
4,019
15,742
45,236
102,247
195,996
OK
ML
0
20
154
965
4,764
16,206
42,210
93,248
54
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Sustainable End-of-Life Management of PV-Panels
State
Scenario
2015
2020
2025
2030
2035
2040
2045
2050
OR
ML
6
269
1,912
6,904
17,518
34,174
54,003
72,087
PA
ML
5
195
1,397
5,250
14,087
29,104
48,791
69,385
Rl
ML
2
103
726
2,471
5,764
10,255
14,626
17,356
SC
ML
12
504
3,553
12,126
28,411
50,792
72,856
87,046
SD
ML
0
1
6
211
1,639
6,081
15,728
33,008
TN
ML
2
103
773
3,941
15,560
44,986
102,209
196,925
TX
ML
47
1,981
14,350
57,685
169,580
382,609
698,611
1,084,438
UT
ML
13
554
3,906
13,305
31,083
55,389
79,150
94,136
VA
ML
9
393
2,852
11,520
34,090
77,385
142,109
221,862
VT
ML
2
106
747
2,525
5,836
10,272
14,467
16,904
WA
ML
2
69
504
2,109
6,541
15,497
29,602
48,071
Wl
ML
2
70
534
3,157
14,690
47,949
120,619
257,253
WV
ML
0
3
25
201
1,275
5,134
15,434
39,546
WY
ML
1
41
289
1,042
2,642
5,152
8,137
10,855
55
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Sustainable End-of-Life Management of PV-Panels
Table B-3. EoL Mass of Solar PV Estimates and Projections, 5-year increments, 2015 to 2050
(metric tons) for the Regular Loss (RL) Scenario by State
State
Scenario
2015
2020
2025
2030
2035
2040
2045
2050
National
RL
16
2,153
36,357
236,255
925,865
2,531,027
5,059,933
7,883,322
AK
RL
0
0
4
26
112
343
788
1,417
AL
RL
0
7
117
880
4,852
20,404
65,253
163,316
AR
RL
0
9
155
1,067
4,757
15,457
38,077
73,849
AZ
RL
1
117
1,977
12,628
47,210
118,733
205,056
246,455
CA
RL
5
711
11,981
76,237
282,676
701,747
1,185,472
1,368,987
CO
RL
0
37
633
4,296
18,563
57,815
135,448
248,633
CT
RL
0
20
335
2,165
8,292
21,652
39,752
52,911
DC
RL
0
3
43
286
1,187
3,495
7,629
12,891
DE
RL
0
4
60
412
1,802
5,705
13,631
25,574
FL
RL
1
140
2,363
15,520
61,937
172,120
346,931
529,254
GA
RL
0
65
1,094
7,002
26,280
66,500
116,027
141,966
HI
RL
0
34
574
3,713
14,285
37,553
69,676
94,282
IA
RL
0
4
61
415
1,782
5,507
12,781
23,215
ID
RL
0
14
232
1,483
5,547
13,966
24,164
29,139
IL
RL
0
9
155
1,138
5,959
23,649
71,717
170,898
IN
RL
0
12
197
1,472
8,064
33,664
106,956
266,080
KS
RL
0
2
33
219
916
2,728
6,039
10,378
KY
RL
0
1
24
196
1,373
7,320
28,517
85,304
LA
RL
0
5
78
548
2,549
8,768
23,020
47,710
MA
RL
1
71
1,193
7,575
27,942
68,800
114,587
128,845
MD
RL
0
31
531
3,439
13,257
34,968
65,219
88,961
ME
RL
0
2
40
337
2,379
12,761
49,941
150,012
Ml
RL
0
5
86
678
4,144
19,418
68,177
185,702
MN
RL
0
37
619
3,962
14,913
37,895
66,584
82,460
MO
RL
0
7
116
800
3,586
11,744
29,191
57,162
MS
RL
0
8
131
903
4,034
13,150
32,517
63,322
MT
RL
0
2
29
215
1,196
5,075
16,365
41,267
NC
RL
1
158
2,659
16,863
62,046
152,171
251,702
279,290
ND
RL
0
0
0
3
42
273
1,082
3,010
NE
RL
0
2
26
183
870
3,084
8,359
17,884
NH
RL
0
3
51
349
1,547
4,981
12,142
23,281
NJ
RL
1
84
1,423
9,040
33,375
82,299
137,423
155,278
NM
RL
0
29
483
3,208
13,127
37,844
80,278
130,936
NV
RL
1
89
1,497
9,776
38,479
104,745
204,890
299,827
NY
RL
0
60
1,021
6,827
28,398
83,832
183,542
311,313
OH
RL
0
9
149
1,089
5,610
21,842
65,051
152,410
OK
RL
0
2
28
222
1,368
6,454
22,797
62,431
56
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Sustainable End-of-Life Management of PV-Panels
State
Scenario
2015
2020
2025
2030
2035
2040
2045
2050
OR
RL
0
22
376
2,457
9,687
26,425
51,853
76,221
PA
RL
0
16
273
1,808
7,345
20,957
43,833
70,215
Rl
RL
0
9
144
924
3,486
8,894
15,731
19,702
SC
RL
0
42
705
4,523
17,104
43,786
77,873
98,441
SD
RL
0
0
1
18
306
2,092
8,467
23,806
TN
RL
0
9
145
1,062
5,503
21,567
64,637
152,338
TX
RL
1
164
2,780
18,800
80,440
247,139
569,361
1,025,434
UT
RL
0
46
775
4,971
18,770
47,943
84,952
106,728
VA
RL
0
33
552
3,739
16,062
49,613
115,059
208,799
VT
RL
0
9
148
949
3,565
9,029
15,776
19,351
WA
RL
0
6
97
665
2,937
9,428
22,902
43,752
Wl
RL
0
6
98
758
4,450
20,000
67,794
178,892
WV
RL
0
0
4
38
294
1,708
7,097
22,511
WY
RL
0
3
57
371
1,462
3,986
7,817
11,482
10. PEER REVIEWERS
This report was peer reviewed by the following external reviewers:
1. Meng Tao, Professor and Fulbright Ambassador (2022 - 2024)
Editor, ECS Journal of Solid State Science and Technology
Laboratory for Terawatt Photovoltaics
School of Electrical, Computer and Energy Engineering
Arizona State University PO Box 875706
Tempe, AZ 85287-5706
2. Bizuneh Workie, Associate Professor
Chemistry Department
College of Agriculture, Science & Technology
Delaware State University
Dover, DE 19901
57
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oEPA
United States
Environmental Protection
Agency
PRESORTED
STANDARD
POSTAGE & FEES
PAID EPA
PERMIT NO. G-35
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(8101R) Washington, DC 20460
Official Business
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58
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