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Chapter 2
A Review of Recycling Processes for Photovoltaic
Marina Monteiro Lunardi,
Juan Pablo Alvarez-Gaitan, José I. Bilbao and
Richard Corkish
Additional information is available at the end of the chapter
The installations of photovoltaic (PV) solar modules are growing extremely fast. As a
result of the increase, the volume of modules that reach the end of their life will grow at
the same rate in the near future. It is expected that by 2050 that figure will increase to 5.56
million tons. Consequently, methods for recycling solar modules are being developed
worldwide to reduce the environmental impact of PV waste and to recover some of the
value from old modules. Current recycling methods can recover just a portion of the
materials, so there is plenty of room for progress in this area. Currently, Europe is the only
jurisdiction that has a strong and clear regulatory framework to support the PV recycling
process. This review presents a summary of possible PV recycling processes for solar
modules, including c-Si and thin-film technologies as well as an overview of the global
legislation. So far, recycling processes of c-Si modules are unprofitable but are likely to be
mandated in more jurisdictions. There is potential to develop new pathways for PV waste
management industry development and offer employment and prospects for both public
and private sector investors.
Keywords: recycling, life-cycle, photovoltaic, waste, end-of-life
1. Introduction
Photovoltaic (PV) solar modules are designed to produce renewable and clean energy for
approximately 25 years. The first substantial PV installations happened in the early 1990s and
since early 2000s solar PV electricity distribution has grown extremely fast [1].
© 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative
Commons Attribution License (, which permits unrestricted use,
distribution, and reproduction in any medium, provided the original work is properly cited.
The cumulative worldwide PV generation capacity reached 302 GW in the end of 2016 [2] and
the predominant technology (90% of the market) is crystalline silicon (c-Si) cells [3]. Also,
during the last years there were several advances on renewable energy in general, including
significant price decline and a constant increase in attention to environmental impacts from
energy sources [4, 5]. Furthermore, the International Technology Roadmap for Photovoltaic
(ITRPV) prediction for the installed PV capacity in 2050 is 4500 gigawatts [6].
As a result of the increase in the global market for PV energy, the volume of modules that reach
the end of their life will grow at the same rate in the near future. At the end of 2016, the
cumulative global PV waste reached 250,000 metric tons, while it is expected that by 2050 that
figure will increase to 5.56 million tons [7].
Much PV waste currently ends up in landfill. Given heavy metals present in PV modules, e.g.
lead and tin, this can result in significant environmental pollution issues. Furthermore, valu-
able metals like silver and copper are also present, which represents a value opportunity if
they can be recovered. Hence, the landfill option cerates additional costs and it does not
recover the intrinsic values of the materials present in the PV modules.
Hence, methods for recycling solar modules are being developed worldwide to reduce the
environmental impact of end-of-life modules and to recover some of the value from old PV
modules. However, current recycling methods are mostly based on downcycling processes,
recovering only a portion of the materials and value, so there is plenty of room for progress in
this area. Moreover, currently only Europe has a strong regulatory framework in place to
support recycling, but other countries are starting to build specific frameworks related to PV
waste. Its clear that sustainable development of the PV industry should be supported by
regulatory frameworks and institutions across the globe, which is not the case at the moment.
There must be adequate management policies for photovoltaic modules when they reach their
end-of-life (EoL) or when they are not able to produce electricity any longer.
As mentioned above, the European Union (EU) provides a legislative framework for extended
producer responsibility of PV modules in European scale through the Waste Electrical and
Electronic Equipment (WEEE) Directive 2012/19/EU [8]. The main objectives of this policy are
to preserve, protect and improve the quality of the environment, to protect human health and
to utilize natural resources prudently and rationally. Since February 2014, the collection, trans-
port and recycling of PV modules that reached their EoL is regulated in every EU country [8].
On the other hand, countries with fast expanding PV markets such as China [9], Japan [10],
India [11], Australia [12] and USA [13] still lack specific regulations for EoL PV modules. These
countries treat PV waste under a general regulatory framework for hazardous and non-
hazardous solid waste or WEEE. However, there are some exceptions.
In 2012 the Japanese government introduced a feed-in tariff[14] that guaranteed the rate for
electricity generated from renewable energy and exported to the grid, which supported rapid
growth of solar module installation in the country. Once all the installed capacity starts
reaching EoL (within 2030 years) they will create a significant waste problem for Japan. In
late 2017, the Japan Photovoltaic Energy Association (JPEA) has published voluntary guide-
lines on how to properly dispose of EoL photovoltaic modules. Also, manufacturers, importers
Solar Panels and Photovoltaic Materials10
and distributors of photovoltaic modules have been invited to provide information on the
chemical substances contained in the product and to inform the waste disposal companies.
JPEA strongly recommend that industry follow the guidelines [15].
In USA, some states go beyond the Resource Conservation and Recovery Act which regulates
hazardous and non-hazardous waste management [13]. California, for example, has additional
threshold limits for hazardous materials classification based on the Senate Bill 489 that catego-
rizes end-of-life PV modules as Universal Waste (facilitating easy transport). This bill is cur-
rently pending United States Environmental Protection Agency approval [16].
In Australia, governments have recognized the significance of guaranteeing that regulations
are in place to deal with the PV waste issue. Ministers agreed that the state of Victoria would
lead innovative programs that seek to reduce the environmental impacts caused throughout
the lifecycle of photovoltaic systems. These efforts are part of an industry-led voluntary
product management arrangement to address the potential emerging risks of PV systems and
their waste. PV modules are listed under the National Product Administration Act to signal the
intention to consider a scheme to deal with such waste [17].
The non-inclusion of PV residues in waste legislation in some countries is due to different
reasons. Solar modules have a lifespan of up to 2530 years [18] and so there has been limited
interest in investigating the aspects of EoL so far. Moreover, the quantity of this type of waste is
still considered insignificant compared to the quantity of other WEEE [19], which currently
makes setting up specific recycling plants for solar modules uneconomical. In addition, the
definition of mandatory requirements for EoL treatment could still be an obstacle to the
effective acceptance of these recycling processes [20]. Because of that, there should be a
continuous focus on scientific evidences on the potential impacts and benefits related to the
treatment of photovoltaic residues.
Furthermore, recycling processes for all the different PV technologies are not yet well devel-
oped. The processes are well developed for mono or multicrystalline silicon. FirstSolar [21] has
an established recycling process for CdTe, but for other thin films there are still room for
improvements. and are being tested and for generation 3 (new materials [22]) the recycling
technologies are not well developed yet.
Only about 10% of PV modules are recycled worldwide. The main reason for that is the lack of
regulation. Actually, it has been shown that, for the current recycling technologies, silicon-
based modules do not have enough valuable materials to be recovered and the cost of the
recycling process is always higher than the landfill option (not considering the externalities),
making recycling an economically unfavorable option [23]. However, the prediction for 2050 is
that the recoverable value could cumulatively exceed 15 billion US dollars (equivalent to 2
billion modules, or 630 GW) [7]. In addition, the recycling of solar PV modules can ensure the
sustainability of the long-term supply chain [24], thereby increasing the recovery of energy and
embedded materials and, also, reducing CO
emissions and energy payback time (EPBT)
related to this industry.
For years, the PV industry and researchers have worked intensively in search of different types
of efficient and cost-effective materials to manufacture solar PV modules and specific ways of
A Review of Recycling Processes for Photovoltaic Modules
keeping them adequately bonded to withstand several years of outdoor exposure. The mod-
ules are made to minimize the amount of moisture that can come in contact with the solar cells
and their contacts while keeping manufacturing costs down. The current standard c-Si module
is bonded using two layers of EVA to bond the layers together. Because of that, recycling solar
modules is a relatively complex task, since these materials need to be separated. Once the
materials/layers of a solar module can be separated, metals such as lead, copper, gallium,
cadmium, aluminum and silicon can be recovered and reused in new products.
Originally created by PV CYCLE in 2007 and commercially available in Europe, the process of
recycling mono or multicrystalline silicon modules begins with the separation of the alumi-
num frame and the junction boxes and then a mechanical process is used for the extraction of
the remaining materials of the module (a process similar to recycling of glass or electronic
waste). The problems with this process are that the value of the material recovered is low (as it
is a downcycling process) and that the maximum amount of recovered materials is about 80%,
which is not sufficient for future requirements, and the value of recovered materials is smaller
than the original [25]. Thin film processes are under development or near implementation in
Italy, Japan and South Korea but costs are not yet competitive. Even up to 90% recovery of
materials is not sufficient when compared to production costs [26]. Lastly for recycling pro-
cesses aiming to generate new materials, the aim is to keep the materials intact for reuse or
direct recycling, recovering the frame, glass, tabbing and solar cells without breakages and in
good condition. The recovery rates can achieve up to 95% and the materials recovered have
higher commercial value. However, these processes are complex and are currently just at
laboratory scale, being studied by a few research groups [27].
Even with the difficulty of recovering rare, toxic and valuable materials from solar modules,
the recycling process has a remarkable environmental advantage [28]. Nevertheless, the need
to recycle this type of waste is imminent. The better knowledge of these technologies and
growth on the waste amounts that could generate profitable outcomes has supported the
development of the first PV recycling plants. Hence, PV manufacturing companies (e.g. First
Solar, Pilkington, Sharp Solar, and Siemens Solar) are investing in the research on solar
modules at EoL [29].
The challenges to design the ideal PV recycling process are many. The focus should be on the
avoidance of damage to the PV cells and module materials, economic feasibility, and high
recovery rate of materials that have some monetary value or are scare or are hazardous, that
can be reused in the supply chain. Finally, the next step for the industry and researchers is to
create module designs that are recycling-friendly[29].
2. Photovoltaic technologies
2.1. Crystalline silicon technology
Crystalline Si (c-Si) technologies dominate the current market share of PV modules (more than
90%). The aluminum back surface field (Al-BSF) [30] is the current industry standard technology
Solar Panels and Photovoltaic Materials12
but the passivated emitter and rear cell (PERC) [31] is gaining importance in the world market
and is expected to replace the Al-BSF technology in the future [3]. The heterojunction (HIT) cells
are also expected to gain some space with predictions of 15% of the total market share by 2027
[7]. Besides that, Si-based tandem solar technologies are expected to appear in mass production
after 2019 [7].
There are different cell structures for crystalline silicon-based PV cells [32]. The cells are
electrically interconnected (with tabbing), creating a string of cells in series (60 or 72 cells are
standard numbers used) and assembled into modules to generate electricity (Figure 1).
A typical crystalline silicon (c-Si) PV module contains approximately 75% of the total weight is
from the module surface (glass), 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) [33]. The rest of the components
have a small percentages of the module weight [29, 34].
The EU directive [8] established recycling targets in terms of module weight and also expresses
the intention to increase the collection rates to allow the progressive recycling of more material
and less to be landfilled. Even with targets aiming for 65% recycling product weight, some of
the current studied recycling processes can recycle over 80% of the weight of a PV module
(Figure 2). However there is still incentive to improve, considering that most of the weight is
from glass and frame, which are relatively easy to remove, depending on the recycling process.
2.2. Thin-film technologies
Thin-films represent less than 10% of the total PV industry [3]. The currently dominant tech-
nologies are cadmium telluride (CdTe), copper indium gallium selenide (CIGS) and amor-
phous silicon (a-Si) with, approximately, 65%, 25% and 10% of the total thin-film market
share, respectively [35].
Figure 1. Silicon solar module basic structure [32].
A Review of Recycling Processes for Photovoltaic Modules
Thin-film solar cells were developed with the aim of providing low cost and flexible geome-
tries, using relatively small material quantities. CdTe, CIGS and a-Si are the main technologies
for thin-film PV modules [36]. CdTe is the most widely used thin-film technology. It contains
significant amounts of cadmium (Cd), an element with relative toxicity, which presents an
environmental problem that has been studied worldwide [37, 38]. CIGS has a very high optical
absorption coefficient because it is a direct band gap material (can be tuned between 1.0 and
2.4 eV by varying the In/Ga and Se/S ratios [39]) and efficiency of approximately 15.7 0.5%
for high bandgap [40]. A-Si has low toxicity and cost but also low durability and it is less
efficient compared with the other thin-film technologies [41]. Current projections expect the a-
Si module market to disappear in the near future, since they cannot compete on costs or
efficiency [3].
Basically, thin-film modules consist of thin layers of semiconducting material (CdTe, CIGS or
a-Si) deposited on a substrate (glass, polymer or metal) (Figure 3).
Figure 2. Total collection rate for WEEE in 2014 as a percentage of the average weight of EEE put on the market in the
three preceding years (20112013) [8].
Figure 3. Thin-film solar module basic structures [36].
Solar Panels and Photovoltaic Materials14
3. Photovoltaic recycling technologies
PV modules are largely recyclable. Materials such as glass, aluminum and semiconductors can,
theoretically, be recovered and reused. Hence it is vital that consumers, industry and PV
producers take responsibility for the EoL of these modules. So far, the most common methods
for recycling c-Si PV modules are based on mechanical, thermal and chemical processes.
Although thin-film solar cells use far less material than c-Si cells, there are concerns about the
availability and toxicity of materials such as tellurium (Te), indium (In), and cadmium (Cd), for
example. Furthermore, the production processes also generates greenhouse gases emissions
during some reactor-cleaning operations. Because of these issues, it is very important to focus
on the recycling of PV modules for all the technologies.
PV Cycle is a not-for-profit organization which goal is to manage PV waste through their
waste management programme for solar PV technologies [42]. PV Cycle was the first to
establish a PV recycling process and PV waste logistics throughout the EU. In 2016 their
process of recycling PV achieved a record recycling rate of 96% for c-Si PV modules (fraction
of solid recycled) [25], which is a percentage that surpasses the current European WEEE
standards. The process begins with the removal of the cables, junction box and frame from
the PV module. Then, the module is shredded, sorted and separated. The separation of the
materials allows them to be sent to specific recycling processes associated with each material.
The summary of this process is shown in Figure 4.
FirstSolar [21] developed a recycling process for CdTe modules. The company manages the
collection and transportation of EoL modules to the recycling centre; however, the recycling
process itself must be financed. This is made by setting aside funds by the company itself at the
time of the module sale, which also happens with WEEE. The summary of this process is
shown in Figure 5.
The recycling process starts with the shredding of the modules into large pieces and subse-
quently in to small fragments (5 mm or less) by a hammer mill. During the next 46 h the
semiconductor films are removed in a slow leaching drum. The remaining glass is exposed to a
mixture of sulfuric acid and hydrogen peroxide aiming, to reach an optimal solidliquid ratio.
After that process, the glass is separated again. The next step is to separate the glass from the
larger ethylene vinyl acetate (EVA) pieces, via a vibrating screen. The glass is cleaned and sent
to recycling. Sodium hydroxide is used to precipitate the metal compounds, after which they
are sent to another company where they can be processed to semiconductor grade raw mate-
rials for use in new solar modules. This process recovers 90% of the glass for use in new
products and 95% of the semiconductor materials for use in new solar modules [21].
Figure 4. Summary of PV cycle recycling process for c-Si modules [25].
A Review of Recycling Processes for Photovoltaic Modules
Also, for recycling CdTe modules, ANTEC Solar GmbH designed a pilot plant with a similar
technology to the First Solar process. It starts with a physical fragmentation of the modules.
After that, these small pieces are exposed to an atmosphere containing oxygen at 300C. These
conditions result in the delamination of the EVA. Subsequently, these fragments are taken to a
400C atmosphere containing chlorine gas which causes an etching process. This step of the
process generates CdCl
and TeCl
that are condensed and precipitated afterwards [43]. The
summary of this process is shown in Figure 6.
A company that has a well stablished c-Si recycling process is the SolarWorld [44]. This
company started recycling in 2003 with a pilot plant using a thermal process. Today, the take-
back of modules is organized via a bring-insystem [44]. Their process is based on a thermal
process, which starts by pyrolising the modules. During this process, the plastic components
are burnt at 600C. The solar cells, glass and metals are separated manually after that. The
glass and some metals are sent to other companies for recycling and the solar cells can be
turned into wafers again. The outcomes of this process are the recovery of more than 84% of
the module weight, being 90% of the glass and 95% of the semiconductor materials [44]. This
process can recover up to 98% unbroken cells depending on the conditions of the module and
the thickness of the cells. The summary of this process is shown in Figure 7.
A pilot project was funded by the Japanese Government via the New Energy and Industrial
Technology Development Organization (NEDO). The recycling process for Si or CIS is based
on pyrolysis of the polymers in a furnace. The process starts with the removal of the frames
and the backsheet foil before the thermal process begins. After that, for CIS only, the EVA resin
Figure 6. Summary of ANTEC solar GmbH recycling process for CdTe modules [43].
Figure 5. Summary of first solar recycling process for CdTe modules [21].
Solar Panels and Photovoltaic Materials16
is burned and the CIS layer is grated. For the c-Si modules, the semiconductor materials are
recovered as well as the glass cullet [45]. The summary of these processes is shown in Figure 8.
In 2014 the Environment Ministry of Japan, through NEDO, together with private companies,
began working on new technologies to pry the PV modules apart. The new technology
appeared to solve a clear problem, the firm attachment of the glass and the cells to the EVA,
and the consequent difficulty to separate them simply by smashing them to pieces and sorting
them out [46].
NPC incorporated is one of the companies that make solar module recycling equipment. The
process, called the hot knife method, can separate the cells of a module from the glass in
about 40 seconds. It places the module between two rollers, which move it along and hold it
steady until it runs into a 1 meter-long steel blade (hot knife) that is heated to 180200C and
slices the cell and the glass apart (Figure 9) [46].
In Japan, the scrap glass can be sold for 0.51 Yen/kg. At that price, the 1015 kg of glass in a solar
module is worth about 15 Yen (approximately 0.14 US D). Their goal was to develop a recycling
technology that can cost less than 5 yen/watt (1000 yen for a 200-watt module, not including
transportation cost) by the end of April 2018, which they already did by January 2018 [46].
Furthermore, some innovative treatment processes for recycling PV solar modules have been
Loser Chemie has some collection points from where they gather several types of photovoltaic
systems (c-Si, CdTe, CIGS and GaAs). The company has developed and patented original
Figure 7. Summary of SolarWorld recycling process for Si modules [44].
Figure 8. Summary of NEDO recycling process for Si modules (pilot project).
Figure 9. Summary of hot kniferecycling process for PV modules [46].
A Review of Recycling Processes for Photovoltaic Modules
processes using mechanical and chemical treatment to recycle solar cells [47]. The first step is
to crush and separate the materials mechanically. In the next stage, they use chemical treat-
ment to recover the semiconductor metals. After that, the aluminum metallisation is also
recovered and can be used for producing wastewater treatment chemicals as aluminum oxide
[47]. The summary of these processes is shown in Figure 10.
Reclaim PV has teamed up with major solar module manufacturers who distribute in Australia
and is refining its processes. The company is developing a process of reclaiming efficient cells
from damaged solar modules. Their cell recycling system is able to extract efficient compo-
nents (but not unbroken cells) from end-of-life solar modules in order to develop new green
products or be reintroduced into the PV industry as new solar modules [48].
4. Photovoltaic recycling technologies studied worldwide
Table 1 summarizes the recycling possibilities for silicon solar modules, as well as the advan-
tages and disadvantages of each process.
Studies show that the impurity levels are an important issue during the recycling processes.
For example, high temperature thermal processes and mechanical processes can create impu-
rities. Also, low temperature processes that are used with specific mechanical or chemical steps
can generate impurities as well. Hence, the ideal outcome can only be achieved with a combi-
nation of thermal, chemical or metallurgical steps [29, 61]. Once materials can be recovered
without impurities, then they will have a higher market value, which is one of the main
obstacles to the growth of the PV recycling industry with the current technologies.
An overview of possible thin-film recycling processes is show in Table 2.
The large-scale recycling of thin-film PV modules is well advanced and, as well as the Si solar
cells, thin-film PV modules are currently processed and recycled using a combination of
mechanical and chemical treatments to achieve meaningful outcomes.
Figure 10. Summary of loser Chemie recycling process for PV modules (pilot project).
Solar Panels and Photovoltaic Materials18
Process Advantages Disadvantages Status Ref.
Organic solvent dissolution Easy access to the EVA
Less cell damage
Recovery of glass
Delamination time
depends on area
Harmful emissions and
Research [49]
Organic solvent and
ultrasonic irradiation
More efficient than sol-
vent dissolution process
Easy access to the EVA
Expensive equipment
Harmful emissions and
Research [50]
Electro-thermal heating Easy removal of glass Slow process Research [51]
Mechanical separation by
hotwire cutting
Low cell damage
Recovery of glass
Other separation pro-
cesses required for full
removal of EVA
Research [52]
Pyrolysis (conveyer belt
furnace and fluidised bed
Separate 80% of wafers
and almost 100% of the
glass sheets
Cost-effective industrial
recycling process
Slightly worse
texturisation (damage to
cell surface)
Solvent (Nitric acid)
Complete removal of EVA
and metal coating on the
It is possible to recover
intact cells
It can cause cell defects
due to inorganic acid
Generates harmful emis-
sions and wastes
Physical disintegration Capable of treating waste Other separation pro-
cesses required for full
EVA removal
Dusts containing heavy
Breakage of solar cells
Equipment corrosion
Commercial [55]
Dry and wet mechanical
No process chemicals
Equipment widely
Low energy requirements
No removal of dissolved
Commercial [56]
Thermal treatment (Two
steps heating)
Full removal of EVA
Possible recovery of intact
Economically feasible
Harmful emissions
High energy requirements
Cell defects and degrada-
tion due to high tempera-
Commercial [57]
Chemical etching Recover high purity
Simple and efficient
Use of chemicals Commercial [5860]
Table 1. Silicon solar modules recycling processes.
A Review of Recycling Processes for Photovoltaic Modules
5. Environmental aspects
Several studies have analyzed the impacts of recycling processes for PV modules on the
environment. There are advantages and disadvantages of the different methods, considering
all the stages, from the collection of the PV modules to the end of the recycling process.
Process Advantages Disadvantages Status Ref.
Organic solvent
Easy access to the
Less cell damage
Recovery of glass
Time for delamination
depends on area
Harmful emissions and wastes
Research [62]
Irradiation by laser Easy access to the
Slow process
Very expensive equipment
Research [63]
Mechanical separation
by hotwire cutting
Low cell damage
Recovery of glass
Other separation processes
required for encapsulant
Research [52]
Vacuum blasting Removal of semiconductor
layers without chemicals
Recovery of clean glass
Relatively slow process
Emission of metals
Further chemical/mechanical
Attrition No usage of chemicals
Recovery of clean glass
Further chemical or mechani-
cal treatments needed
Flotation Relatively simple process
Low use of chemicals
High losses of valuables dur-
ing rinsing and sieving process
Flotation process required
Dry etching Simple process High energy demand
High effort for purification
Commercial [43]
Physical disintegration Capable of treating waste Other separation processes
required for encapsulant
Dusts containing heavy metals
Breakage of solar cells
Equipment corrosion
Commercial [55]
Dry and wet
mechanical process
No process chemicals
Equipment widely
Low energy requirements
No removal of dissolved solids Commercial [56]
Chemical etching High purity materials
Simple and efficient
Use of chemicals Commercial [5860]
Thermal treatment Full removal of
Recovery of intact cell
Simple and economical
Harmful emissions
High energy requirements
Cell defects and degradation
Commercial [55]
Leaching Complete removal of
High use of chemicals
Generation of acidic fumes
Complex control of chemicals
Commercial [64]
Table 2. Thin-film solar modules recycling processes.
Solar Panels and Photovoltaic Materials20
An environmental study made for the European Full Recovery End-of-Life Photovoltaic
(FRELP) project showed that environmental impacts from c-Si recycling processes come from
plastic incineration and some chemical and mechanical treatments (sieving, acid leaching,
electrolysis, and neutralization) for the recovery of metals [65].
Additionally, before the recycled silicon from solar cells can be used again, further
chemical treatment is necessary, as well as for silver and aluminum. The chemical treat-
ments have the potential of producing environmental impacts. Besides that, it is impor-
tant to note that no process can recycle 100% of recovered materials from solar modules
yet [28].
Nevertheless, for the PV Cycle [25] c-Si recycling process it was shown that there is a signifi-
cant decrease in Global Warming Potential impacts (up to 20% compared to the process of
making cells) [66] and for CdTe modules, there is and environmental benefit from the glass and
copper recycling [67].
When comparing c-Si recycling and landfill EoL scenarios it was found that the environ-
mental impacts from the recycling process are lower than for landfill, assuming that the
recycled resources go back to the PV cells and modules manufacturing. These results consid-
ered that the recycling process involving dismantling, remelting, thermal and chemical treat-
ments [28].
It can be seen that there are opportunities and challenges related to PV recycling processes.
Although it was already show that there are environmental benefits, the recycling methods
still need to improve in order to achieve better recovery rates and work on the transportation
6. Economic aspects
The recovery of valuable materials during the recycling of PV modules can have great eco-
nomical value. The extraction of secondary raw material from EoL PV modules, if made in an
efficient way, can make them available to the market again [68].
Attention has been paid particularly to silver. PV modules that reach their EoL will build up a
large stock of embodied raw materials (as mentioned previously), which can be recovered and
become available for other uses or even for solar cells again. However, this will not occur
before 2025, according to some forecasts [68].
The ITRPV predicts that, by 2030, the total material value recovered from PV recycling can
reach USD 450 million. With this amount it is possible to produce 60 million PV modules
(18 GW), which would be approximately 33% of the 2015 production [7]. Considering Si, up to
30,000 t of silicon can theoretically be recovered in 2030 [7], which is the amount of silicon
needed to produce approximately 45 million new modules. Considering a polysilicon current
prices at USD 20/kg and a recovery rate from commercial recycling processes of 70% this is
equivalent to USD 380 million [7].
A Review of Recycling Processes for Photovoltaic Modules
7. Conclusions
The current study presented an overview of possible PV recycling process for solar modules,
including c-Si and thin-film technologies. The motivation, legislation and current processes
were discussed and possible issues were addressed.
So far, recycling processes of c-Si modules results in a net cost activity when compared to
landfill (due to the avoidance of the true environmental costs and externalities for the latter)
but these processes can ensure the sustainability of the supply chain in the long-term, increase
the recovery of energy and embedded materials, while reducing CO
emissions and energy
payback time (EPBT) for the whole PV industry. The unprofitability of the current methods
does not mean that the recycling of PV modules should be discarded. The PV waste manage-
ment has the potential to develop new pathways for industry development and offers employ-
ment prospects to investors, for both public and private sector [7].
It is well known that the recycling of EoL PV modules has positive influences on the environ-
mental impacts. Recycling of PV modules can remove and retain potentially harmful sub-
stances (e.g. lead, cadmium, and selenium), recover rare materials (e.g. silver, tellurium and
indium) and make them available for future use [8]. To achieve the best possible results at
acceptable costs, it is essential that future recycling processes stay up to date on the continuous
innovations in solar cells and modules technologies.
However, the current waste volumes are still low, which entails economical obstacles for the
development of the existing processes. If we compare the economics of recycling electronics
and telecommunications, where the profits are generated through the recovery of precious
metals and parts, it is unlikely for PV solar modules to have sufficient amounts of these
materials to pay for the associated costs of the steps of recycling processes [69].
It is important that specific legislation is established for PV waste management and recycling and
that this step is given before the amount of waste from EoL PV modules becomes alarming, as
forecast for the year 2030 [7]. Regulation will help, but it might not be the only way. The
economic viability should be achieved as well. If a recycling process for PV waste that is revenue
positive (i.e. a good business) can be created, then it will happen regardless of regulations.
It was shown that recycling technologies for PV wastes are extensively explored not just on
labs and pilot plants, but some are also commercially available. It is also clear that a few
challenges (e.g. economic feasibility, recovery of more materials, and recovery of unbroken
cells), still remain in process efficiency, complexity, energy requirements and use of non-
environmentally friendly materials for the treatment of some elements.
MML and RC acknowledge the support of the Australian Government through the Australian
Renewable Energy Agency (ARENA). Responsibility for the views, information or advice
Solar Panels and Photovoltaic Materials22
expressed herein is not accepted by the Australian Government. Additionally, the first author
would like to acknowledge Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
for her scholarship.
Author details
Marina Monteiro Lunardi
, Juan Pablo Alvarez-Gaitan
, José I. Bilbao
and Richard Corkish
*Address all correspondence to:
1 The Australian Centre for Advanced Photovoltaics (ACAP), School of Photovoltaic and
Renewable Energy Engineering, University of New South Wales, Sydney, Australia
2 School of Civil and Environmental Engineering, University of New South Wales, Sydney,
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A Review of Recycling Processes for Photovoltaic Modules
... This means that the produced energy should be have a smaller ecological footprint in comparison with any other way of producing it (usually compared with fossil fuels sources). One way of measuring this ecological footprint may be by the ratio of CO 2 per produced power during all the source lifetime (since the manufacturing up until the recycling) [9,[20][21][22][23]. ...
... These added resistances have an effect on the other quantitative indicators as well, such as FF, which can be re-calculated using Expression (20), where FF 0 is the fill factor value determined using Expression (12) [33]. ...
... Since Cadmium can the harmful to humans, some concerns are raised about the possibility of contamination in case of fire on a CdTe domestic power plant. CdTe is contained within the molten glass when under flame temperatures of 760-1100°C [13,20,21]. ...
Full-text available
Photovoltaic technology has become a huge industry, based on the enormous applications for solar cells. In the 19th century, when photoelectric experiences started to be conducted, it would be unexpected that these optoelectronic devices would act as an essential energy source, fighting the ecological footprint brought by non-renewable sources, since the industrial revolution. Renewable energy, where photovoltaic technology has an important role, is present in 3 out of 17 United Nations 2030 goals. However, this path cannot be taken without industry and research innovation. This article aims to review and summarise all the meaningful milestones from photovoltaics history. Additionally, an extended review of the advantages and disadvantages among different technologies is done. Photovoltaics fundamentals are also presented from the photoelectric effect on a p-n junction to the electrical performance characterisation and modelling. Cells’ performance under unusual conditions are summarised, such as due to temperature variation or shading. Finally, some applications are presented and some project feasibility indicators are analysed. Thus, the review presented in this article aims to clarify to readers noteworthy milestones in photovoltaics history, summarise its fundamentals and remarkable applications to catch the attention of new researchers for this interesting field.
... Multiple options for separating the module laminate (subsequently referred to as delamination) as a first process step in the recycling of c-Si modules have been investigated [3,4] and evaluated from an environmental and techno-economic standpoint [5][6][7]. These options include the use of organic solvents for chemical delamination and high temperature for thermal delamination. ...
The recycling of photovoltaic modules has been a topic of increasing interest over the last years. At industrial scale, delamination of the module structure, which represents the first step in the recycling process, is currently achieved by multi-stage crushing. However, the quality of the outputs obtained through subsequent processing is low and offers room for improvement. Milling was investigated as an alternative physical delamination method. Lab-scale experiments were conducted to evaluate the applicability of the technology in general, as well as comparing a process by which all non-glass layers are removed at the same time (1-step) with one where the backsheet is removed as a separate fraction (2-step). Furthermore, a qualitative and quantitative analysis of the resulting outputs in each case was performed. Results show effective delamination by the milling process. Advantages in comparison to the currently used delamination techniques are identified in regard to the quality of the recovered glass, which is separated directly during delamination as well as the fact that the subsequent processing can therefore be focused on the polymers, metals and silicon contained within the removed materials. Some possibly problematic aspects in regard to upscaling have also been identified and discussed. While the 2-step process enables the recovery of more homogenous outputs, it is also associated with a higher effort regarding input characterization and the milling process itself. In order to reach a conclusion about which process option is more feasible, additional investigations concerning the milling process, the input material and the output fractions are needed.
... In common practice, mechanical, thermal, chemical processes, or a combination of any of them, are used to treat and recycle EoL PV solar modules. Particularly, various recovery and recycling techniques are currently being explored by many researchers to maximize the usage of waste PV solar panels (Chowdhury et al., 2020;Lunardi et al., 2018). For instance, Huang and colleagues (W.-H.W.-H. ...
The utilization of solar technology for clean energy generation has seen a dramatic increase over the past decade. Eyeing the ever-growing solar capacity and the subsequent inevitable deluge of solar panel wastes, the ideal approach to handle End-of-Life (EoL) solar photovoltaic (PV) panels is to recycle their materials for reuse. This present study explores an optimal recycling process with a high resource recovery efficiency on a laboratory pilot scale, which comprise of three main steps: module delamination, acid etching and sequential electrodeposition. A high recovery of 86, 95 and 97% were achieved for silver, lead and aluminum, respectively. The acquired results are further applied in a life cycle assessment. The process was scaled up to simulate an industrial process and its human and environmental impacts were compared to those of the landfilling disposal method, with six main impact categories analyzed and described: global warming potential, human toxicity potential, freshwater ecotoxicity potential, acidification potential, eutrophication potential and ozone depletion potential. Mitigation strategies are also proposed. Lastly, economic analysis demonstrated that at a treatment capacity of 892.5 kg/h, the process is feasible with an internal revenue rate of 28.2% and a payback time of less than a year, provided the waste collection is subsidized.
... Also, as the current volumes of PV waste are pretty low in many countries, most recyclers do not consider it a full capitalised business opportunity at a commercialised scale [18]. It has been estimated that only 10% of the total solar PV waste is currently recycled globally, which indicates that there is a massive gap in the availability of the operational infrastructure [48]. The fact that the three commercially viable closed-loop EOL solar PV waste management models are predominantly [33] operational in the EU [49] also points to the same conclusion. ...
Increasing energy demands and commitments in relation to climate change have accelerated the deployment of solar power globally, especially in India. Grid-connected solar capacity in the country has increased ∼11 times in just five years, from 2.6 GW in March 2014 to 28.18 GW in March 2019. However, this development has inevitably also led to the emergence of significant volumes of solar photovoltaic (PV) waste, which will only increase in the upcoming years, a considerable challenge for its waste management system. The environmental and human health risks associated with the unscientific dumping of solar PV waste have been well established in the existing literature, presenting the need to develop an effective strategy to manage this emerging waste stream. This paper presents a review of literature about India's solar PV waste management sector with a view to understanding the ground realities and identifying challenges and barriers that hinder the adoption of a regularised strategy for its management using the DPSIR framework approach. It goes on to propose a regulatory framework aimed at mainstreaming the end-of-life (EOL) management of solar PV waste in India after evaluating strategies that have already been used worldwide. In line with the Extended Producer Responsibility (EPR) concept, a multistakeholder, multi-sectoral and systematic approach has been adopted to develop a specific regulatory framework for India. The framework was subjected to a SWOT analysis to evaluate its functionality. The SWOT analysis indicates that one of the critical strengths of the framework is that it is based on a participatory approach to be adopted by all stakeholders for managing this emerging waste stream.
Improper disposal of waste solar panels can raise serious concerns about the environment and human health. Therefore, it is important to recycle the waste panels to ensure that the modules do not pollute the environment. Different techniques developed globally for the recycling of waste photovoltaic modules include organic solvent dissolution, electro-thermal heating, and thermal treatment. The present study is focused particularly on the optimization of the parameters to identify i) an efficient solvent for the dissolution of the encapsulant, ii) position of the module for improved dissolution, iii) the effect of temperature variation on solubility, and iv) saturation studies of EVA. It is concluded that Trichloroethylene at 70 °C works effectively for the separation of different components with the ratio of 1:7.44 of the module to solvent in a horizontal position. The maximum percentage of a module in the solvent is 13.44% and an increase in this percentage will result in an ineffective separation. A novelty approach has been reported for the first time to experimentally determine the quantity of solvent, position of the module, and the lowest temperature required for encapsulant dissolution.
This work assessed the economic sustainability of photovoltaic panels (PV) recycling. The PV throughout and silver (Ag) concentration in PVs are the main factor affecting recycling. For high Ag concentrations (0.2%), the recycling is sustainable without PV recycling fee if the PV throughput is higher than 18,000 t/yr. Lower processing volumes enable sustainability only with recycling fees from 0% up to 46% of the total annualized costs in the throughput range 18,000–9000 t/yr. For low Ag concentrations (0.05%) recycling fees are instead always needed to achieve profitability, unless the throughput is higher than 43,000 t/yr. Given the high Ag revenues, efforts should be done towards its recovery. If however a mixed silver-silicon fraction was sold for more than 50–70% of its actual value depending on the Ag concentration, a simplified process without hydrometallurgical separation could generate higher profitability on the short and long term. Given the decreasing Ag content in PVs, the profitability in recycling also depends on when the investments are realized. In the medium Ag concentration scenario and for Ag prices of 600 $/kg, PV fees are always required for the net present value (NPV) to be higher than CAPEX. The later the investment, the higher the PV throughputs and PV fees required to generate the same NPV. Investing in 2025 under the hypothesis of a regular loss scenario and an Ag price of 750 $/kg is the only condition that produces NPVs higher than CAPEX without PV fees if the throughput is at least 30,000 t/yr.
Full-text available
The targeted global decarbonization demands the urgent replacement of conventional fossil fuel with low carbon technologies. For instance, solar energy is abundant, inexhaustible, non-polluting, and low-priced; however, to produce energy on large scale with reliable, cost-efficient, and environmentally friendly methods remains a challenge. The outstanding optical properties of Cu(In,Ga)Se2 thin film photovoltaics and their intrinsic compatibility with industrial-scale production are paving a way towards this technology. However, most of the activity in the field relies on the use of non-environmentally friendly methodologies to achieve solution-processed flexible and lightweight photovoltaics with significant efficiencies. Importantly, there is a search for more sustainable alternatives that are compatible with roll-to-roll industry to improve the cost-effectiveness and sustainability of photovoltaics without compromising the photovoltaic performance. Herein, we review cost-efficient and sustainable fabrication methodologies that complement the current high-energy-demanding vacuum-based fabrication of Cu(In,Ga)Se2 photovoltaics. The existent non-vacuum deposition methods of Cu(In,Ga)Se2 photoabsorbers are presented and precursors and solvents used in ink formulations are discussed in terms of sustainability. The approaches resulting in most efficient photovoltaic cells are highlighted. Finally, all-solution-processed Cu(In,Ga)Se2 photovoltaics are reviewed, along with the non-vacuum deposition methods of the individual layers, contributing to an even higher throughput and low-cost production. This review highlights the relevance and potential of sustainable non-vacuum methodologies, as well as the need of further investigation in this field to ultimately give access to high-end CIGS PVs with low-cost fabrication.
Recently, lead halide perovskite solar cells have become a promising next-generation photovoltaics candidate for large-scale application to realize low-cost renewable electricity generation. Although perovskite solar cells have tremendous advantages such as high photovoltaic performance, low cost and facile solution-based fabrication, the issues involving lead could be one of the main obstacles for its commercialization and large-scale applications. Lead has been widely used in photovoltaics industry, yielding its environmental and health issues of vital importance because of the widespread application of photovoltaics. When the solar cell panels especially perovskite solar cells are damaged, lead would possibly leak into the surrounding environment, causing air, soil and groundwater contamination. Therefore, lots of research efforts have been put into evaluating the lead toxicity and potential leakage issues, as well as studying the encapsulation of lead to deal with leakage issue during fire hazard and precipitation in photovoltaics. In this review, we summarize the latest progress on investigating the lead safety issue in photovoltaics, especially lead halide perovskite solar cells, and the corresponding solutions. We also outlook the future development towards solving the lead safety issues from different aspects.
Technical Report
Full-text available
The “Snapshot of Global Photovoltaic Markets” aims at providing preliminary information about how the PV market developed in the last year. IEA-PVPS collects information from official governmental bodies and reliable industry sources. Information about countries outside the IEA-PVPS network is collected through the industry network, industrial associations, IRENA and REN21. The information is condensed in this snapshot report in order to provide the best preliminary overview of global PV market development.
Full-text available
Cumulative photovoltaic (PV) power installed in 2016 was equal to 305 GW. Five countries (China, Japan, Germany, the USA, and Italy) shared about 70% of the global power. End-of-life (EoL) management of waste PV modules requires alternative strategies than landfill, and recycling is a valid option. Technological solutions are already available in the market and environmental benefits are highlighted by the literature, while economic advantages are not well defined. The aim of this paper is investigating the financial feasibility of crystalline silicon (Si) PV module-recycling processes. Two well-known indicators are proposed for a reference 2000 tons plant: net present value (NPV) and discounted payback period (DPBT). NPV/size is equal to −0.84 €/kg in a baseline scenario. Furthermore, a sensitivity analysis is conducted, in order to improve the solidity of the obtained results. NPV/size varies from −1.19 €/kg to −0.50 €/kg. The absence of valuable materials plays a key role, and process costs are the main critical variables.
Full-text available
Purpose This work assesses the environmental benefits of including the recycling strategies for PV modules at the earlier design stage of PV grid-connected systems (PVGCS) considering simultaneously techno-economic and environmental criteria. Methods First, two case studies from dedicated literature have been selected based on the availability of the life cycle inventory, i.e., recycling of PV modules of crystalline silicon (c-Si) and cadmium telluride (CdTe) technologies. Second, different scenarios have been formulated by varying the mix of virgin and recycled PV modules. Third, following an ecodesign framework, a bi-objective (Energy production versus Energy Payback time) optimization approach for the design of PVGCS encompassing the recycling stage has been developed to assess the formulated scenarios. The ecodesign methodology couples the life cycle assessment method with a PVGCS design model, which is then embedded in an external optimization loop based on a multi-objective genetic algorithm, i.e., a NSGA-II variant. Results For c-Si, the recycling strategy significantly reduces the EPBT (a factor of 1.8 is observed from the 100% virgin to the 100% recycled scenario) when considering an identical PV module efficiency and a significant decrease in Global Warming Potential (GWP), expressed in g CO2 eq per kWh, is also observed with a 20% reduction in the more extreme case. For CdTe thin film modules, the results confirm the environmental benefit when recycling of glass cullet and copper is considered. Although PV recycling modules are energy intensive, their implementation compensate for the energy used for producing virgin modules. Conclusion This study confirms that the end-of-life management of PV modules must be thoroughly studied not only to determine the feasibility of the process but also to assess the environmental and economic benefits.
Technical Report
Full-text available
Solar photovoltaic (PV) deployment has grown at unprecedented rates since the early 2000s. Global installed PV capacity reached 222 gigawatts (GW) at the end of 2015 and is expected to rise further to 4,500 GW by 2050. Particularly high cumulative deployment rates are expected by that time in China (1,731 GW), India (600 GW), the United States (US) (600 GW), Japan (350 GW) and Germany (110 GW). As the global PV market increases, so will the volume of decommissioned PV panels. At the end of 2016, cumulative global PV waste streams are expected to have reached 43,500-250,000 metric tonnes. This is 0.1%-0.6% of the cumulative mass of all installed panels (4 million metric tonnes). Meanwhile, PV waste streams are bound to only increase further. Given an average panel lifetime of 30 years, large amounts of annual waste are anticipated by the early 2030s. These are equivalent to 4% of installed PV panels in that year, with waste amounts by the 2050s (5.5‑6 million tonnes) almost matching the mass contained in new installations (6.7 million tonnes). Growing PV panel waste presents a new environmental challenge, but also unprecedented opportunities to create value and pursue new economic avenues. These include recovery of raw material and the emergence of new solar PV end-of-life industries. Sectors like PV recycling will be essential in the world’s transition to a sustainable, economically viable and increasingly renewablesbased energy future. To unlock the benefits of such industries, the institutional groundwork must be laid in time to meet the expected surge in panel waste. This report presents the first global projections for future PV panel waste volumes to 2050. It investigates and compares two scenarios for global PV panel waste volumes until 2050. • Regular-loss: Assumes a 30-year lifetime for solar panels, with no early attrition; • Early-loss: Takes account of “infant”, “mid-life” and “wear-out” failures before the 30-year lifespan. Policy action is needed to address the challenges ahead, with enabling frameworks being adapted to the needs and circumstances of each region or country. Countries with the most ambitious PV targets are expected to account for the largest shares of global PV waste in the future, as outlined by case studies in this report. By 2030 the top three countries for cumulative projected PV waste are projected to include China, Germany and Japan. At the end of 2050 China is still forecast to have accumulated the greatest amount of waste but Germany is overtaken by the United States of America (US). Japan comes next followed by India. At present, only the European Union (EU) has adopted PV-specific waste regulations. Most countries around the world classify PV panels as general or industrial waste. In limited cases, such as in Japan or the US, general waste regulations may include panel testing for hazardous material content as well as prescription or prohibition of specific shipment, treatment, recycling and disposal pathways. The EU, however, has pioneered PV electronic waste (e-waste) regulations, which cover PV-specific collection, recovery and recycling targets. Based on the extended-producerresponsibility principle, the EU Waste Electrical and Electronic Equipment (WEEE) Directive requires all producers supplying PV panels to the EU market (wherever they may be based) to finance the costs of collecting and recycling end-of-life PV panels put on the market in Europe. Lessons can be learned from the experience of the EU in creating its regulatory framework to help other countries develop locally appropriate approaches. End-of-life management could become a significant component of the PV value chain.1 As the findings of the report underline, recycling PV panels at their endof- life can unlock a large stock of raw materials and other valuable components. The recovered material injected back into the economy can serve for the production of new PV panels or be sold into global commodity markets, thus increasing the security of future raw material supply. Preliminary estimates suggest that the raw materials technically recoverable from PV panels could cumulatively yield a value of up to USD 450 million (in 2016 terms) by 2030. This is equivalent to the amount of raw materials currently needed to produce approximately 60 million new panels, or 18 GW of power-generation capacity. By 2050, the recoverable value could cumulatively exceed USD 15 billion, equivalent to 2 billion panels, or 630 GW.
Full-text available
Recent developments in photovoltaic materials have led to continual improvements in their efficiency. We review the electrical characteristics of 16 widely studied geometries of photovoltaic materials with efficiencies of 10 to 29%. Comparison of these characteristics to the fundamental limits based on the Shockley-Queisser detailed-balance model provides a basis for identifying the key limiting factors, related to efficient light management and charge carrier collection, for these materials. Prospects for practical application and large-area fabrication are discussed for each material. © 2016, American Association for the Advancement of Science. All rights reserved.
Full-text available
Lifecycle impacts of photovoltaic (PV) plants have been largely explored in several studies. However, the end-of-life phase has been generally excluded or neglected from these analyses, mainly because of the low amount of panels that reached the disposal yet and the lack of data about their end of life. It is expected that the disposal of PV panels will become a relevant environmental issue in the next decades. This article illustrates and analyses an innovative process for the recycling of silicon PV panel. The process is based on a sequence of physical (mechanical and thermal) treatments followed by acid leaching and electrolysis. The Life Cycle Assessment methodology has been applied to account for the environmental impacts of the process. Environmental benefits (i.e. credits) due to the potential productions of secondary raw materials have been intentionally excluded, as the focus is on the recycling process. The article provides transparent and disaggregated information on the end-of-life stage of silicon PV panel, which could be useful for other LCA practitioners for future assessment of PV technologies. The study highlights that the impacts are concentrated on the incineration of the panel׳s encapsulation layers, followed by the treatments to recover silicon metal, silver, copper, aluminium. For example around 20% of the global warming potential impact is due to the incineration of the sandwich layer and 30% to the post-incineration treatments. Transport is also relevant for several impact categories, ranging from a minimum of about 10% (for the freshwater eutrophication) up to 80% (for the Abiotic Depletion Potential – minerals).
„Wenn niemand etwas dagegen tut, dann verwandelt sich alles in einen mausgrauen Matsch“ – so formulierte Boulding bereits 1971 seine Ansicht zu der Tatsache, dass der menschliche Abfall in höherem Ausmaß zur Entropie beiträgt, als der natürliche fortwährende Prozess des sich Vermischens, der ohnehin auf der Erde abläuft. Der Mensch hat sich zunächst den Lagerstätten mit den höchsten Konzentrationen zugewandt und wird nunmehr zukünftig gezwungen sein, mit immer weniger konzentrierten Vorkommen zurechtkommen zu müssen. In dieser Zeit, in der vielerorts erwogen wird, wie diverse Materialien aus Rohstofflagerstätten mit geringsten Gehalten gewonnen werden können, eröffnet sich ein vielversprechender Weg – die Wiederverwendung, das Recycling.
The environmental burden of multi-Si PV modules in China has been discussed in existing studies, however, their data are mostly from local enterprises, and none of their environmental assessment involves the decommissioning and recycling process. This study quantitatively assesses the life-cycle environmental impacts of Chinese Multi-crystalline Photovoltaic Systems involving the recycling process. The LCA software GaBi is applied to establish the LCA model and to perform the calculation, and ReCiPe method is chosen to quantify the environmental impacts. LCA of production process reveals that Polysilicon production, Cell processing and Modules assembling have relatively higher environmental impact than processes of Industrial silicon smelting and Ingot casting and Wafer slicing. Among the 14 environmental impact categories evaluated by ReCiPe methodology, the most prominent environment impacts are found as Climate Change and Human Toxicity. LCA including recycling process reveals that although recycling process has environmental impact, the recycling scenario has less environmental impact by comparing with the landfill scenario. Among the five manufacturing processes and recycling process, environmental impacts of polysilicon production, cell processing and modules assembling have relatively higher uncertainty, probably because that the environmental impact of these processes is high, and standard error of parameters such as electricity, aluminum and glass in the three processes are high. Findings of our study indicate that proper measures should be taken in the high pollution processes such as polysilicon production and cell processing. In addition, efforts should also be made to enhance the recovery rate and seek for more environmental friendly materials in the recycling process.
Perovskite solar cells based on CH3NH3PbI3 and related materials have reached impressive efficiencies that, on a lab scale, can compete with established solar cell technologies, at least in short-term observations. Despite frequently voiced concerns about the solubility of the lead salts that make up the absorber material, several life cycle analyses have come to overall positive conclusions regarding the environmental impact of perovskite solar cell (PSC) production. Their particularly short energy payback time (EBPT) in comparison to other established PV technologies makes them truly competitive. Several studies have identified valuable components such as FTO, gold and high temperature processes as the most significant contributors to the environmental impact of PSCs. Considering these findings, we have developed a rapid dismantling process allowing the recovery of all major components, saving raw materials, energy and production time in the fabrication of recycled PSCs. We demonstrate that the performance of PSCs fabricated from recycled substrates can compete with that of devices fabricated from virgin materials.
Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined, and new entries since January 2016 are reviewed. Copyright © 2016 John Wiley & Sons, Ltd.