An assessment of EU’s photovoltaic panel waste policies: current framework and strategic vision for 2050

Abstract

This study provides a comprehensive analysis of photovoltaic (PV) panel waste management, examining both technical aspects and legislative frameworks, particularly focusing on European Union (EU) regulations through 2050. The research addresses the challenges in recycling PV panels, including their extended lifespan and potential environmental risks from solvent emissions. The study emphasizes sustainable waste management practices and the critical need for effective recycling techniques under the EU’s Waste from Electrical and Electronic Equipment (WEEE) Directive. The research highlights the rapid growth of solar energy sector and its implications for waste management, stressing the importance of Extended Producer Responsibility policies. It critically evaluates the WEEE Directive’s limitations regarding PV panel segregation, recycling, and collection procedures. The study emphasizes the significance of public awareness and international cooperation for future waste management by 2050. Finally, it proposes specific amendments to EU legislation to enhance sustainability in social-ecological electricity generation and support global warming mitigation efforts.

1. Introduction

Photovoltaic (PV) electricity generation is becoming an increasingly preferred method each year, standing out in terms of both its environmental impacts and financial returns. The broad scope of ‘PV electricity generation’ includes not only technical issues but also social dynamics. For this reason, when examining PV electricity generation, one should not look at a single point and the issue should be discussed in detail in terms of application and policy areas. These range from policy decisions, economic incentives, and market dynamics to cultural shifts, public perceptions, and behavioral adaptations. Given the intricate and symbiotic relationship between these social and ecological elements, it becomes evident that ‘PV electricity generation’, in its entirety, can be aptly described as a social-ecological system (D’Adamo et al. 2023).

The recent shift away from nuclear energy in Europe and around the world, coupled with the rapid increase in the number of solar power plants, signifies that solar electricity generation will continue to be a popular method for many more years. Emphasizing the importance of ecological conservation, the transition to renewable energy sources like solar power is imperative. However, while the push for solar energy aids in preserving ecology—not in the phase of setting up the system but producing electrical energy without greenhouse gas (GHG) emission—it does come with its set of challenges. As the adoption of solar energy grows, so does the need to address waste management concerns, particularly regarding expired or damaged PV panels. Without effective waste management systems in place, the challenge of storing and managing this waste becomes a pressing issue. Moreover, improper disposal of these panels can further harm the ecology, emphasizing the need for holistic approaches to renewable energy transitions. According to various estimates, approximately 80 million metric tons of solar panel waste will be produced worldwide by 2050, with about 10 million tons in Europe alone (Weckend, Wade, and Heath 2018). The majority of these panels are made up of first-generation monocrystalline or polycrystalline panels (Kant and Singh 2022). Because these panels are more readily available, cheaper and more reliable than second-generation panels, they are the most sold and most used panels in solar power plants. Looking at the last decade, Chinese PV panel producers took over the market and took the sales leadership from many European panel producing countries, including Germany, and were able to launch cheaper panels (Terzi, Sherwood, and Singh 2023). Although this was very positive news for end users in terms of cost, it also contributed to the uncontrolled spread of PV technology. Unfortunately, first-generation panels contain metals such as Al, Cu, In, Ga, and Ag, which can cause serious toxicity when mixed with various natural sources (Deng et al. 2019; Kwak et al. 2020). Additionally, due to both their weight and volume, they are not easy to store. For these reasons, recycling PV panels has become a critically important issue that needs serious attention.

When a deeper examination is made, there is an important detail neglected in the PV panel waste projections for 2050. The PV panels installed in solar power plants established in the early 2000s and later will become waste by the early 2030s. With the increasing trend of solar power plant installations, the projected 80/10 million tons target may be reached 10–15 years earlier, possibly even in the 2040s. As can be understood from the references given in this study, the first wave of PV panel waste increase will probably hit the world in the 2030s and the second wave can start around 2040. It is essential to take serious measures to recycle this waste and prevent this process from becoming a problem for the world before we reach 2050.

Considering European Union (EU) law, it seems clear that a significant overhaul is needed. In our research, we found that the issues related to the recycling of PV panels and waste management in the EU legislation were given superficially and without any detail, and we concluded that this could lead to different, incomplete, and inadequate practices, creating a serious problem for Europe; therefore, the idea of this study emerged. Both updating legislation and developing policies toward this goal should be on the agenda. Understanding the historical development of PV panels and the current state of solar technology, examining GHG emissions arising from the production, installation, and recycling of PV panels; setting policy development goals related to the recycling of PV panels; and understanding their main recycling, reuse, and disposal methods are all essential areas to master in developing legislation. The most accurate assessments of the current state of the EU law can only be made after adequate information is obtained on these issues, and the best recommendations for new legislation can be made after that. With this perspective in mind, this work has been planned following a similar roadmap in four parts including Conclusions and policy implications to determine the basic principles of the possible amendments required in the EU law for the formation of an effective PV panel waste management in the light of the proposed waste management strategies for a sustainable ecology.

2. PV panel generations and applications

2.1 PV panel generations

The first-generation wafer-based solar cells, crafted from crystalline silicon and GaAs, were introduced in the 1970s. By 1990s, these first-generation GaAs-based solar cells achieved an efficiency exceeding 20 per cent, and they were widely utilized for space applications (Bosio, Pasini, and Romeo 2020). In the present day, silicon-based first-generation solar cells constitute about 90 per cent of the PV solar cell industry. There are primarily two types of silicon-based solar cells available in the market: monocrystalline and polycrystalline. Monocrystalline cells dominate the majority of commercial applications; hence, the term ‘silicon-based cell’ is often used to refer to these cells in the market context. Polycrystalline cells provide a more cost-effective alternative, but monocrystalline cells offer higher efficiency and demonstrate greater resilience to immediate weather changes (Kant and Singh 2022).

The 1970s marked the arrival of second-generation solar cells. These are predominantly thin-film solar cells created from materials such as amorphous silicon (a-Si), cadmium telluride (CdTe), copper indium gallium diselenide (CIGS), and gallium arsenide (GaAs). Thin-film solar technology introduced several advantages, including simplified manufacturing, cost-effectiveness, lower environmental impact, and suitability for various building-integrated PV (BIPV) applications due to their lighter and more flexible nature. Despite these benefits, the technology has noteworthy shortcomings in terms of environmental impact, cost, lifespan, and degradation. Consequently, efforts are underway to address these challenges and emphasize the use of environmentally safe materials with improved efficiency and reduced cost (Gloeckler, Sankin and Zhao 2013; Ramanujam and Singh 2017; Nakamura et al. 2019; Diermann 2021; Akcay et al. 2023; Cheng et al. 2023; Wu et al. 2023; Li et al. 2023). Looking at the percentage of global annual production graph of PV production by technology (Fig. 1), it is very clear that monocrystalline PV panels dominates the market in the last 5 years as they did between 1980 and 2000. This can be easily explained by their reducing production cost and accessibility.

Emerging third- and fourth-generation solar cells aim to overcome the limitations of their predecessors, including organic, perovskite, quantum dot, copper zinc tin sulfide (CZTS), and dye-sensitized solar cells (DSSCs). CZTS and DSSCs, for instance, represent the new frontier in thin-film solar cell technology. CZTS, having properties akin to CIGS, presents a nontoxic and cost-effective alternative, albeit with an efficiency ceiling of 13.6 per cent (Green et al. 2022). Organic solar cells, made mainly of polymers, offer affordability, lightweight, flexibility, and environmental friendliness, yet they require enhanced efficiency and stability.

In 2018, Meng et al. achieved a remarkable 17.3 per cent efficiency with solution-processed tandem cells (Meng et al. 2018), while perovskite cells reached an impressive 25.7 per cent efficiency by 2021 (NREL 2023). Originating in 2009 with a modest 3.8 per cent efficiency (Kojima et al. 2009), perovskite technology, evidenced by its impressive efficiency increase in just 12 years, is now the fastest-evolving solar technology. Despite this rapid advancement, perovskite technology currently lags behind first-generation solar cells in commercial applications due to challenges in stability and scalability (Khatoon et al. 2023). Moreover, the fact that all perovskite cells contain lead raises potential ecological and health concerns (Babayigit et al. 2016).

Perovskite, quantum dot solar cells (QDSCs), and DSSCs contribute exciting advancements within the third generation. Perovskite cells excel in light absorption and efficiency but face stability and environmental challenges. DSSCs use sensitizing dye to generate charge carriers, offering a potential low-cost, eco-friendly solution, especially in low-light conditions, yet stability and efficiency obstacles persist.

DSSCs, as a new generation of thin-film solar cells, involve a semiconductor between a photo-sensitized anode (TiO₂) and an I−/I₃− electrolyte. While cost-effective and nontoxic, they struggle with power conversion efficiency, stability, and scalability, with the highest recorded efficiency at 12 per cent (Mathew et al. 2014; Sharma, Sharma, and Sharma 2018).

QDSCs leverage semiconducting nanoparticles with quantum properties, providing tunable absorption and multiexciton generation. Despite reaching 18.1 per cent efficiency, stability and nontoxic material development are ongoing challenges (NREL 2023; Prakash, Das, and Maiti 2023).

The fourth generation, hybrid inorganic solar cells, combines polymer flexibility with organic nanostructure stability. Though not yet on the market, developments in organic nanomaterials, particularly graphene-based materials, suggest a promising future as a flexible, stable, and cost-effective alternative to crystalline solar cells (Iqbal et al. 2022).

All the PV panels mentioned in this work are examined in detail in Figs 2, 3, 4, and 5.

2.2 Application of PV panels

Solar PV has a wide range of applications, from small-scale installations to utility-scale power generation facilities. Recently, building-attached PV and BIPV systems have demonstrated remarkable development. Building-attached PVs generally prioritize power generation and are applied to existing buildings, while BIPVs are typically used to replace conventional building materials in building envelopes and thermal insulation (IEA 2021; Custódio et al. 2022; Meng et al. 2022).

Indoor PVs (IPVs) have gained traction due to increasing demand for Internet of Things devices and self-powered devices. IPVs are expected to enhance reliability and lifespan in wireless networks (Mathews et al. 2019). However, compared to outdoor light harvesting, indoor light harvesting is less effective. While the indoor efficiency of silicon cells is about 8 per cent, their outdoor efficiency can reach up to 26 per cent. To improve indoor performance, researchers are exploring various PV technologies, with thin-film solar cells and third-generation solar cells emerging as promising materials for IPVs due to their optical absorption and wider energy bandgaps (Hyuk Kim et al. 2023; Li et al. 2023; Mathews et al. 2019).

In the agriculture sector, the integration of PV technologies into irrigation systems to replace traditional fossil fuel-based generators for pumping is becoming increasingly popular. In agricultural PV applications, irrigation and PV energy production coincide on the same site. Given the dependency of both types of production on weather conditions, the management of the irrigation network must accommodate variable power availability (Mérida García et al. 2020; IEA 2021).

Among infrastructure applications of solar PV technologies, street lighting systems are commonly implemented, driven by environmental considerations. Nevertheless, the high cost of solar PV devices and the size of energy storage units represent significant challenges to overcome for the broader adoption of solar PV in street lighting (Liu 2014).

Historically, solar PV technology has been used in spacecraft applications since the launch of Vanguard-1 and Sputnik-3, the first solar-powered satellites, in 1958 (Bermudez-Garcia, Voarino and Raccurt 2021). However, the utilization of solar PV electricity to meet transportation demand is still under development (Ardani et al. 2021).

Utility-scale solar PV facilities, which generate electricity from the sun over vast areas using hundreds of solar panels, have been established worldwide to meet the rapidly increasing global energy demand. Currently, electricity generation from utility-scale solar PV facilities is one of the least costly options in many countries (IEA 2023). According to the International Renewable Energy Agency, the total global installed solar capacity reached 1047 Gigawatts in 2022, and significant additions to solar PV capacity are expected in the energy market in the coming years (IRENA 2022).

As can be understood from the application areas of PV panels given earlier, their prevalence is increasing day by day, and due to their cost advantage, the demand for—easily accessible in the market—monocrystalline panels, which may cause problems in recycling and waste management processes, is increasing.

3. Recyling and waste management of PV panels

3.1 Environmental effects of PV panels

PV panels are central to global United Nations Green Energy goals, with rapidly increasing installations worldwide (Ogbomo et al. 2017). However, managing End-of-life Solar PV (EOL-PV) panels presents significant challenges (Bošnjaković et al. 2023). The European Green Deal’s Zero carbon emission target promotes sustainable waste management through the 7R approach: Rethink, Refuse, Reduce, Reuse, Repair, Regift, and Recycle. When reuse or repair is not viable, recycling becomes the priority before disposal (Xu et al. 2018). As mentioned before by 2050, if PV panels are not properly recycled, it is estimated that approximately 80 million tons of solar panel waste will be generated (Divya et al. (2023). Recycling PV panels for reuse may create an effective opportunity to improve economic returns, and more researchers are focusing on studies related to the recycling of PV panels every day (Trivedi, Meshram, and Gupta 2023).

PV panels deteriorate through delamination, color degradation, corrosion, and breakages. Environmental exposure causes metal corrosion, while mechanical shocks, sunlight, and hail lead to structural damage (Wang 2016). Recycling these panels is crucial for both economic and ecological reasons, particularly given their content of rare elements and valuable metals. The cost of generating new raw materials can be decreased by using recycled materials. A key driver of the PV market will be the development of an appropriate recycling mechanism (Liu et al. 2022).

Rare elements or valuable metals are used as component materials in some types of solar cells. PV panel recycling is therefore essential for both economic and ecological reasons. PV panels are recycled using chemical and physical purification techniques that have been effectively utilized in other sectors. These advanced technologies enable the separation and recycling of PV panel materials (Wang 2016). The main focus of solar panel material recycling is on glass, pure silicon, and trace amounts of precious metals. Glass is recycled through delamination, achieving high recovery rates and purity. This process is carried out using physical, chemical, and thermal methods (Deng et al. 2019).

The precious metals (aluminum, silver, copper, etc.) in PV panels originate from PV cell layers. These precious metals can be recovered by chemical precipitation (Dias et al. 2021). Additionally, methods such as electrostatic recycling, high-temperature oxidation, and polishing can be applied. Although the metal content is small compared to other materials, increasing the metal enrichment rate is crucial for reducing recycling costs and supporting resource management and sustainability.

Through chemical processes, impurities are removed from PV cells by etching and silicon layers are recovered. Recycled silicon wafers perform similar to those used in commercial solar cells, and the market expects them to perform well. However, further R&D is needed to improve the economic viability of recovered materials and the purification of waste solutions produced by etching, to enhance the competitiveness of recycled silicon layers. Each leach solution used produces liquid waste that must be managed, as it may be toxic to humans and the environment (Radziemska et al. 2010; Zhang et al. 2017; Sharma et al. 2021).

Although solar panel production is more environmentally friendly than traditional energy industries and achieves zero CO₂ emissions during operation, the waste generated during and after production harms the environment. This damage cannot be ignored (Qi and Zhang 2017; Wang et al. 2022). If lead (Pb), tin (Sn), cadmium (Cd), silicon (Si), and copper (Cu), the main components of solar cells, originate from separated products in disposal facilities, they are harmful to ecosystems and human health (Deng et al. 2019; Kwak et al. 2020). Studies show that leakage waters from some PV panel recycling processes may release Pb, Cr, Cd, Sb, and Se at levels exceeding legal limits in soil and water (Tammaro et al. 2016). Ecotoxicological tests reveal that over 80 per cent of leakage water is ecotoxic, threatening biodiversity and aquatic life. Thus, PV panels as waste pose a significant environmental risk (Tammaro et al. 2016).

3.2 PV panels’ recycling processes and waste management

The extensive recycling of solar panels has not yet reached the level of other recycling techniques. Positive panel terminals are composed of silver, which has recycling value, and other precious elements such as indium, gallium, and germanium are also present, even though solar panels do not contain rare earth metals. However, recycling solar panels poses challenges, including the emission of solvents during the process (Wang et al. 2022).

Waste management for PV panels involves collection, dismantling, preprocessing, and recovery (Wang et al. 2022). Preprocessing and recovery use various methods, including physical, thermal, chemical, mechanical, thermochemical, and physico-thermal processes (Zhang et al. 2017). Solar panel recycling is categorized into three main processes (Radziemska et al. 2010):

1. Delamination,

2. Material separation, and

3. Metal extraction.

Delamination is achieved through thermal, mechanical, and chemical methods. Pyrolysis is used to recover high-purity glass and silicon wafers while completely removing the polymer. To prevent toxic gas emissions from the polymer during pyrolysis, two-stage pyrolysis is recommended. Ethylene-vinyl acetate (EVA) is removed at high temperatures during pyrolysis. Energy recovery could address the high energy consumption of pyrolysis, but further research is needed to improve wafer fragility and optimize energy recovery during thermal processing. High voltage pulsed crushing can increase the metal enrichment ratio, while mechanical delamination is simple, cost-effective, and environmentally friendly. However, crushed materials require appropriate separation techniques due to their complexity, and fractured glass and wafers have lower recovery value than intact ones. Chemical delamination at low temperatures maintains good sheet integrity, but pyrolysis is still needed to dissolve EVA adhered to PV cells. Research is required to develop safer, more effective, and economically viable chemical reagents, as most currently used reagents are toxic organic chemicals.

EVA can dissolve in HNO₃ within 24 h, and metals can also dissolve from the solar cell surface. Longer etching times may dissolve silicon (Si). Organic solvents such as acetone, toluene, and ethanol are used to dissolve EVA, but the chemical process is more complex due to the use of expensive and hazardous chemicals. Wastewater management is a critical issue requiring significant financial investment and safety standards (Fiandra et al. 2019).

Thermal modification of EVA through heating is faster and waste-free compared to chemical processing (Farrell et al. 2020). Pyrolysis thermochemically breaks down EVA, producing valuable compounds and releasing less CO₂. Common pyrolysis furnaces include conveyor belt furnaces, fixed bed furnaces, and bubbling fluidized bed reactors. All recycling processes, including the proposed process flow diagram, highlight points of hazardous waste output (marked with hazard symbols) and are emphasized in Fig. 6.

Regular storage is often used when recycling infrastructure is insufficient, costs are high, or final disposal methods are uncertain. However, without more economically and environmentally sustainable solutions, the accumulation of PV panels in landfills poses a significant waste problem for the future. Organizations such as the United Nations and the EU emphasize the importance of promoting recycling and reuse as alternatives to regular disposal (Kwak et al. 2020). A major challenge in sending PV module waste to landfills is the lack of clear guidelines regulating sampling methods, particle size, and minimum sample sizes. To address this, adopting a repeatable sampling protocol tailored to PV waste management is critical (Preet and Smith 2024).

Incineration is another method used for PV panel disposal, involving the destruction of waste materials at high temperatures. While it effectively reduces waste volume, it results in the loss of valuable recyclable materials such as silver, aluminum, and silicon. Additionally, incineration increases carbon emissions, worsening climate change. For these reasons, incineration is considered a last resort, with recycling and energy recovery recommended as priorities (Kumar, Holuszko, and Espinosa 2017). Both regular storage and incineration are inadequate for long-term environmental sustainability, and there is a growing global need for more efficient recycling techniques. PV waste disposed of through these methods is considered the least favorable option due to its harmful effects on the environment and economy (Akram Cheema et al. 2024).

End-of-life (EOL) PV panels used as landfill contribute to environmental hazards and the loss of valuable metals. When waste PV panels are stored in regular storage areas or incinerated, they return as pollution to the soil, water, and air (Kumar, Holuszko, and Espinosa 2017; Farrell et al. 2020). Life Cycle Assessment (LCA) studies of PV panel recycling reveal that improvements are needed in subprocesses involving chemical and thermal recycling methods (Tammaro et al. 2016). Recycling impacts on the environment, energy requirements, and social aspects of PV panels must be considered, and both traditional and nontraditional LCA approaches should be conducted (Gerbinet, Belboom, and Léonard 2014). To encourage recycling, it is essential to develop low-cost, environmentally friendly, and efficient recycling technologies that enhance the performance of recovered materials. This ensures proper waste management and strengthens the competitive power of recycled materials in the market (Seo, Kim, and Chung 2021).

According to electronic waste recycling policies, 65 per cent by weight recycling is mandatory for EOL-PV panels. However, many organizations expose these wastes to environmental hazards and cause the loss of valuable metals such as Si, Pd, Cd, Te, Ga, and As by directly sending them to disposal facilities (Trivedi, Meshram, and Gupta 2023). A PV waste management system must be established. The EU revised the Waste from Electrical and Electronic Equipment (WEEE) directive in 2012, requiring Europe to achieve an 85 per cent bulk recovery rate and an 80 per cent recycling rate for waste PV panels (Parliament 2012). However, unless this requirement transforms into a global approach with proper waste management programs, it will not lead to sustainable progress worldwide. The WEEE and related directives lack detailed guidelines for waste management systems, including disposal and recovery methods.

Evaluating the future outcomes of current research, development, and testing efforts for PV panel recycling techniques remains challenging. The absence of globally competent policies and the superficial nature of existing laws hinder future projections and pose a significant obstacle to addressing these issues effectively. Without comprehensive global regulations, the potential for sustainable PV waste management remains limited.

4. EU legislation on PV panels and strategy recommendations

PV panels’ state-of-the-art, differentiated material composition, generations of PV panels, and possible volumes of PV panel waste are explained in the previous parts. With states across Europe shifting from traditional energy production methods (carbon-based and nuclear power plants) to renewable energy production methods, production in the PV panel industry has rapidly increased. As mentioned earlier, incorrect recycling or disposal of PV panel waste will lead to the loss of lead, with cadmium not being properly filtered, and the loss of traditional resources (Al and glass) and rare metals (Ag, In, Ga, and Ge) Publications Office of the EU (2013).

In the EU acquis, the Waste Electrical and Electronic Equipment Directive (2002/96/EC) was established in 2003 for the management of waste electrical and electronic equipment and was revised twice in 2008 and 2012. PV panel waste was included in the scope of the revised WEEE (2012/19/EU) dated 13 August 2012 (Parliament 2012). This directive provides the basic legal framework for producer responsibility in PV panels at EU scale.

In EU law, the concept of Extended Producer Responsibility (EPR) refers to the organizational responsibility of producers, importers, or sellers for managing the collection, processing, and financing of waste when a product placed on the European market reaches the end of its life cycle and becomes waste. This responsibility approach aims to promote waste management and recycling, thereby reducing the amount of waste and enhancing environmental sustainability.

In EU law, the principle of EPR is regarded as one of the cornerstones of the EU’s waste policy, as reflected in various EU regulations that enforce the waste hierarchy (Fig. 7). It encourages producers to minimize the waste they generate and to reduce the treatment of waste if generated. Waste Management Directive Framework of EU is given in Fig. 8 to understand EU’s point of view clearly.

There is also a Directive dated 8 June 2011 and numbered 2011/65/EU on the Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment. According to Article 2/4-(i) of this Directive, PV panels intended to be used in a system that is ‘designed, assembled, and installed by professionals for permanent use at a designated location for the purpose of generating solar energy for public, commercial, industrial, and residential applications’ are not included in the scope of this Directive.

Since 2012, the obligations imposed by the principle of EPR, as outlined in the WEEE Directive, have also been applicable to PV panel waste. Prior to 2012, the EU Packaging Directive and Battery Directive imposed EPR obligations for certain PV products delivered to PV installations, as well as for the batteries used in their packaging. Additionally, the principles of the EU Waste Framework Directive were applied to PV panel waste management.

WEEE directive, which started to be implemented from 14 February 2014, regulates the collection, transportation, and recycling of PV panels; EU Member States have incorporated these directive provisions into their national laws.

The WEEE aims to take necessary measures to protect environmental and human health by reducing the negative impacts that the production and management of electrical and electronic equipment waste will have on the environment within the EU region (Shittu, Williams and Shaw 2021). Another goal of the directive is to contribute to sustainable development in the EU region, along with the purposes of protecting the environment and human health. To achieve these objectives, appropriate management of waste within the scope of the WEEE, collection, reuse, recycling, and recovery of waste whose lifespan has ended have been adopted.

PV panel waste was first included in the scope of the Directive in July 2012 with the amendments applied. Although the WEEE includes provisions related to PV panels, it does not specifically define PV panels. However, the obligations and responsibilities of producers, distributors or sellers, importers, and electronic/distance sellers regarding PV panel waste are regulated within the WEEE. Apart from the obligations and responsibilities of real or legal persons who are qualified as PV panel manufacturers and are responsible for processing PV panel waste, certain obligations of EU Member States are also regulated in the WEEE.

Under Article 4 of the WEEE, EU Member States are obligated to take measures to encourage cooperation between PV panel manufacturers and recyclers to facilitate the reuse, dismantling, and recovery of components and materials of PV panel waste and to design and produce their recyclable products. According to Article 4 of the WEEE, Member States shall apply the eco-design requirements facilitating the reuse and processing of WEEE determined within the framework of Directive 2009/125/EC, and producers are prohibited from reusing WEEE through certain design features or production processes, unless these special design features or production processes provide overwhelming advantages in terms of environmental protection and/or safety requirements.

According to the provision of Article 5/1 of the WEEE, Member States will take appropriate measures to ensure proper processing of PV panel waste in particular and primarily to ensure a high level of their collection and to minimize the disposal of this waste. Again, according to the provision of Article 6 of the WEEE, Member States have undertaken to prohibit the disposal of PV panels that have been separately collected and not yet processed. Additionally, Member States will ensure that the collection and transportation of separately collected PV panels are carried out in such a way as to provide the most suitable conditions for the preparation of hazardous substances for reuse, recycling, and containment.

If possible, to maximize the preparation for the reuse of PV panels, according to Article 6 of the WEEE, Member States will encourage the separation of PV panels prepared for reuse from other separately collected waste electrical and electronic equipment at collection points where collection schemes or facilities are suitable, providing staff access from reuse centers before any other transfer.

According to Article 7 of the WEEE, each Member State will ensure the application of the EPR principle and, based on this, achieve a minimum annual collection rate for PV panel waste. Starting from 2019, the minimum collection rate to be achieved annually will be either 65 per cent of the average weight of PV panels put on the market in the relevant Member State in the last 3 years or alternatively 85 per cent of the PV panels produced on the territory of that Member State. Furthermore, according to Article 7 of the WEEE, Member States can set higher rates for the separate collection of WEEE and will inform the Commission in such a case. It is stated that ‘producer responsibility’ can be a good example for the PV panel waste management in USA as well (McElligott 2020).

According to Article 8/1 of the WEEE, Member States are obliged to ensure that all WEEE collected separately are subjected to appropriate treatment. Within this scope, proper treatment, excluding preparation for reuse and recovery or recycling operations, will minimally include the removal of all fluids and selective treatment in accordance with the conditions specified in Annex IV of the WEEE. In terms of the appropriate method, Member States will ensure that producers or third parties acting on their behalf establish systems using the best available techniques to recover PV panels. These systems can be set up individually or collectively by producers; Member States, on the other hand, will ensure that any organization or enterprise carrying out collection or treatment operations stores and treats PV panels in accordance with the technical requirements specified in Annex VIII of the WEEE.

Mentioned obligations in WEEE Directive are summarized in Table 1. The Directive imposes a set of eight obligations on producers of Electrical and Electronics Equipment, including PV panels, where the producer must realize.

According to the WEEE, the Commission is authorized to adopt delegated legislation to implement other treatment technologies that provide at least the same level of protection for human health and the environment, in accordance with Article 20 concerning the amendment of Annex VII. The Commission will primarily assess whether the records regarding printed circuit boards for mobile phones and liquid crystal displays need to be amended. The Commission may invite an evaluation of whether amendments in Annex VII are needed to address nanomaterials present in waste electrical and electronic equipment.

In terms of processing PV panel waste, to protect the environment, Member States may set minimum quality standards for the treatment of collected waste as regulated in the WEEE. Member States preferring such quality standards will inform the Commission, which will publish the standards. Regarding these quality standards, the WEEE provides that the Commission can request European standardization organizations to develop European standards for the treatment of waste, including recovery, recycling, and preparation for reuse, by 14 February 2013, at the latest. These standards will reflect the latest technology; to ensure uniform conditions for the implementation of this provision, the Commission may adopt implementing acts that set minimum quality standards based on standards developed by European standardization organizations. Member States will encourage organizations or enterprises carrying out treatment operations to implement certified environmental management systems in accordance with Regulation (EC) 1221/2009 of the European Parliament and of the Council of 25 November 2009 on the voluntary participation of organizations in a Community eco-management and audit scheme.

In the light of shared information, literature and EU law and legislations review, to cope with a significant portion of the waste PV panels, expected to reach around 80 million tons globally by 2050 (Weckend, Wade, and Heath 2018), and to overcome the challenges this situation presents, policymakers and industry stakeholders should consider the following strategies:

4.1 Strengthening regulations and standards

The EU should review and update existing law and legislation, such as WEEE, specifically to address waste PV panel management. This could include setting targets for waste collection, transport, and treatment, as well as recycling and recovery rates (Maitre-Ekern 2021). The content of EU law that is recommended to be updated by applying the strategies shared in this part and to what extent it should be updated is discussed in the last part of this work. The strategies and possible amendments shall include a technical framework of PV panel recycling as given in Section 3 of this manuscript and shall detail the waste management processes to avoid different applications in the Member States.

4.2 Encouraging research and innovation

Investing in research and innovation can lead to advancements in recycling technologies and eco-design for PV panels, reducing their environmental impact. Collaboration among industry, academia, and policymakers is key to developing sustainable solutions (May, Stahl and Taisch 2016). Despite high economic costs, the long-term benefits of reducing environmental damage and fostering a circular economy for PV panels justify the investment (Majewski et al. 2021; Wang et al. 2022).

4.3 Increasing public awareness and participation

Public awareness is vital for effective waste management (Hasan 2004). Educational campaigns and community projects can promote responsible disposal and the adoption of eco-friendly energy technologies. Increased awareness could lead to the use of more efficient and durable solar panels (Chowdhury et al. 2020).

4.4. Enhancing international cooperation

Global cooperation is crucial for managing PV waste. Countries can share best practices and develop common strategies (Latunussa et al. 2016). For instance, China’s growing solar energy capacity presents environmental risks due to improper disposal (Xu et al. 2018), similar to challenges faced in Australia (Matsenko et al. 2020) and India (Vargas and Chesney 2020). A cooperative approach focusing on EPR could help mitigate these issues.

In summary, by promoting comprehensive waste management and innovation, the EU can address the challenges of PV waste while supporting a sustainable energy transition (Daniela-Abigail et al. 2022). However, it is crucial to examine recycling and waste management processes carefully (Levenda, Behrsin and Disano 2021).

Thinking as an example, there is no detailed information or guidance in WEEE about ‘establishment of regional collection centers’ or ‘selection of waste facility locations’. Since panels can become waste even before the end of their life cycle, it is essential to establish collection centers in addition to monitoring businesses where solar installations are set up. The recycling of these waste panels is highly costly, making it critical to ensure the safe disposal of this hazardous waste. Also, the locations where solar panel facilities are built must be carefully chosen. Panels can easily become waste due to external factors such as rocks or lead. Additionally, bird migration paths should be considered, as bird droppings can create hotspots, leading to the deformation of the panels and causing them to become waste earlier than expected.

5. Conclusions and policy implications

In light of the previous parts of the work and the examination of the EU’s current law, some conclusions have been drawn in order to establish a more sustainable PV waste management legislation for the EU. Primarily, it is an undeniable fact that the 2050 PV Waste Projection needs to be updated in line with new energy production demand trends and that even before this date, two waves of serious PV waste problems will be confronted. The PV panel waste of approximately 10 million tons in the 2050 projection will mean the growth of risk created by components such as metals, which are not easily recyclable and can pose danger to nature when not recycled, contained in the first-generation panels.

There are many topics referred to in the current EU legislation, but they have not been thoroughly examined for the Union and the details have been left to the member countries. According to WEEE Annex IV, PV panels are named as large equipment and are within the scope of this directive. While WEEE Annex VII lists components that need to be separated from electronic waste, it does not specifically mention any PV panel component. Also, according to WEEE Annex VIII, member countries are obliged to take necessary measures and process all electronic waste that could be pollutant.

As seen, WEEE, including its annexes, does not detail how to collect, recycle, or segregate and dispose of PV panels. It has completely left it to member countries, expecting them to develop local legislations. However, the possibility of EU member countries, which focus on the different strategic goals in terms of energy, environmental pollution, and global warming, acting independently on such an important issue can lead to terrifying results. Strategies proposed in the previous part should have been followed to create an efficient international collaboration both between the member countries and the others, but unfortunately, because there is no compulsory law or policy, this is still not realized. In this context, it is certainly necessary to conduct a study based on ‘Technical’ and ‘Legal’ principles for the expansion of legislation on PV panels.

The principles given in Fig. 9 can be detailed as follows.

Technical principles

Producer panel collection rates: The minimum annual collection target stipulated in Article 16 of WEEE is 65 per cent by weight and 85 per cent by unit. It would be appropriate to gradually increase these ratios, bringing them to 70–90 per cent by 2030 and to 75–95 per cent after 2030.

Panel collection methods: The process of how panels that have entered waste status should be collected and transported to the manufacturer’s facilities should be determined, as should which panels should be considered as EOL panels. The operation of lifespan and usability tracking for PV facilities should also be outlined.

Proper logistics: It should be determined how panels collected for recycling should be transported, which areas they should be sent to, and how logistics during recycling or disposal processes should be regulated.

Proper storage: How PV panels ready for recycling or in the midst of recycling processes should be stored and/or disposed of without causing any agricultural soil loss should be determined.

Recyling methods of EOL-PV panels: As discussed in this study, the main framework of processes such as demolition, separation, extraction, and disposal should be outlined, and recycling methods and processes for materials inside PV panels should be defined with a minimum loss of recyclable materials and, if possible, zero toxicity probability.

Disposal methods of PV panel wastes: Once metals and other materials are recovered from PV panels, methods for the disposal of nonrecoverable waste, potentially toxic and other waste, or the types of facilities to which these materials will be directed should be identified.

Integrated waste management: How the above six technical principles can be implemented together and how the Integrated Waste Management recommended in Fig. 2 can be operated should be determined.

Legal principles

Producer responsibility: The principle of producer responsibility accepted in WEEE should be accepted as a fundamental principle in the proposed directive for the collection and recycling of PV panels. There should be binding provisions regarding technical principles that the producer must comply with.

Sanctions for improper use of PV panels: In the proposed directive, provisions should be made for the recycling and waste disposal of PV panels before the end of their lifespan, and penalties should be imposed for noncompliant behaviors.

Incentives for PV plant conversions: In the proposed directive, measures such as incentives for the use of new generation panels should be introduced to implement the objective of limiting the use of second-hand PV panels that have not reached the end of their lifespan.

New generation PV plant investment incentives: In the proposed directive, investment incentive principles should be arranged for the use of new generation panels in newly established PV plants.

Investment incentives for producer facilities: Incentive mechanisms should be established for facilities to be established for the purpose of new generation panel production or for existing panel production facilities to be adapted to new generation panel production.

The fundamentals of integrated waste management: It is necessary to determine the minimum technical and legal conditions that actors involved in integrated waste management need to meet.

The waste management, recycling, and disposal of PV panels primarily resemble the process that the EU experienced with Incandescent Light Bulbs. Incandescent Light Bulbs were gradually banned in Europe as of 1 September 2009, with EU Directive No. 2005/32/EC. The purpose of this ban was to ensure energy efficiency and reduce GHG released during light production for illumination purposes. Incandescent Light Bulbs, which consume approximately 10 W electricity for every 1 W light they produce, are energy-inefficient, low-efficiency, and short-lived light sources. Thanks to the relevant directive, it was aimed to prevent a certain amount of global warming, which is a global threat and the cause of climate change. When considering PV panels, the situation appears to be even more serious. The mentioned toxicity risks, storage problems, chances of EOL panels being remarketed, and disposal issues indicate that PV panels pose a much greater risk than Incandescent Light Bulbs in terms of global warming and environmental pollution.

In light of the details given earlier, the recommended amendments and improvements to be made in the current EU law can be seen as a new and very strategic step in the fight against global warming for the EU. It is essential to recognize that acting upon these principles is of paramount importance for the preservation of ecology. Moreover, for the ‘PV electricity generation’ as a socio-ecological system to operate more efficiently, effectively, and sustainably, the implementation of these principles holds significant significance. Beyond that, this strategic step to be taken for the more efficient use of our world’s limited resources and to prevent environmental pollution by eliminating indirect polluting elements of clean energy production can play a very important role in making it more reliable and sustainable.

5.1 Next steps for policymakers and researchers

To address the challenges and opportunities outlined in this study, the following next steps are recommended for policymakers and researchers:

Policymakers: Should prioritize the development of comprehensive and detailed EU-wide legislation on PV panel waste management. This includes setting clear targets for collection, recycling, and recovery rates, as well as establishing a framework for international cooperation. The proposed principles for updating EU law, as detailed in Fig. 9, should be considered and implemented to ensure a unified approach across Member States. Additionally, incentives for the adoption of new generation PV panels and investment in recycling infrastructure should be explored to promote sustainable practices.

Researchers: Should focus on advancing recycling technologies and eco-design principles for PV panels. This includes developing more efficient and cost-effective methods for material recovery, particularly for valuable metals and silicon. Research into the environmental impacts of PV panel waste and the effectiveness of current recycling processes should be expanded to inform policy decisions. Collaboration with industry stakeholders is essential to translate research findings into practical solutions that can be implemented on a large scale.

Conflict of interest.

None declared.

Funding

None declared.

References