PV Waste Management at the Crossroads of Circular Economy and Energy Transition: The Case of South Korea

Response to the Upcoming Emerging Waste: Necessity and Feasibility Analysis of Photovoltaic Waste Recovery in China

With the widespread photovoltaic deployment to achieve the net-zero energy goal, the resulting photovoltaic waste draws attention. In China, considerable steps have not been taken for photovoltaic waste management. The lack of relevant scientific information on photovoltaic waste brings difficulties to the establishment of photovoltaic waste regulatory systems. In this study, the necessity and feasibility of photovoltaic waste recovery were investigated. In China, the photovoltaic waste stream was quantified as 48.67-60.78 million t in 2050. In photovoltaic waste, indium, selenium, cadmium, and gallium were in high risk, judging by the metal criticality analysis, which meant that their recovery was significant to alleviate the resource shortage. The full recovery method was proved to reduce the environmental burdens most. For cost and benefit analysis, the net present value/size was -1.02 $/kg according to the current industrial status. However, it can be profitable with the recovery of silver. This study provides scientific and comprehensive information for photovoltaic waste management in China and is expected to promote the sustainable development of photovoltaic industry.

Prediction of Power Output from a Crystalline Silicon Photovoltaic Module with Repaired Cell-in-Hotspots

Recycling of problematic photovoltaic modules as raw materials requires considerable energy. The technology to restore cells in hotspot modules at a relatively low cost is more economical than replacing them with new modules. Moreover, a technology that restores power by replacing a cell-in-hotspot of a photovoltaic module with a new cell rather than replacing the whole module is useful for operating power plants. In particular, power plants that receive government subsidies have to use certified modules of specific models; the modules cannot be replaced with other modules. Before putting resources into module restoration, predicting the power of a module to be restored by replacing a cracked cell with a new cell is essential. Therefore, in this study, the module output amount after restoration was calculated using the previously proposed relative power loss analysis method and the recently proposed cell-to-module factor analysis method. In addition, the long-term degradation coefficient of the initial cell and the loss due to the electrical mismatch between the initial and new cell were considered. The output of the initial cell was estimated by inversely calculating the cell-to-module factor. The differences between the power prediction value and the actual experimental result were 1.12% and 3.20% for samples 190 A and 190 B, respectively. When the initial rating power and tolerance of the module were corrected, the differences decreased to 0.10% and 2.01%, respectively. The positive mismatch, which restores cells with a higher power, has no loss due to the reverse current; thus, the efficiency of the modules is proportional to the average efficiency of each cell. In this experiment, the electrical mismatches were only 0.37% and 0.34%. This study confirmed that even if a replacement cell has a higher power (<20%) than the existing cell, the power loss is not significantly affected, and heat generation of the existing normal cell is not observed. Hence, it was concluded that when some cells are damaged in a crystalline solar cell, the module could be restored by replacing only those cells instead of disposing of the entire module. However, for commercialization of the proposed method, a long-term reliability test of the module repaired using this method must be performed to confirm the results. Following this, recycling cells instead of recycling modules will be an economical and eco-friendly alternative.

Global Challenges and Prospects of Photovoltaic Materials Disposal and Recycling: A Comprehensive Review

The considerable amount of waste PV modules expected to emerge from recent widespread of solar photovoltaic (PV) systems is a cause of concern, especially in sustainability terms. Currently, most end-of-life (EoL) PV modules are either disposed of in landfills or bulk recycled in existing recycling facilities. Although these approaches are easier in execution as less efforts are directed at sustainable management of these modules, they can potentially cause environmental issues including loss of valuable resources and leakage of toxic materials. Hence, high-value closed-loop recycling is much preferred for its environmental merits, although its implementation brings forward challenges that this paper attempts to shed light on. This review paper aims to provide an overview of the EoL management of PV modules, concentrating on the challenges faced in PV recycling. Additionally, PV waste-related regulatory frameworks implemented in different countries are discussed. Recommendations to improve the EoL management of PV modules and trade-offs arising from conflicting solutions are proposed. To establish a sustainable PV waste management framework, legislations promoting the extended producer responsibility (EPR) principle, presence of suitable infrastructure, research and development (R&D) and cooperation of various governmental and private bodies are highly needed.

Simplified Recovery Process for Resistive Solder Bond (RSB) Hotspots Caused by Poor Soldering of Crystalline Silicon Photovoltaic Modules Using Resin

When the thickness of the solar cell wafer and the amount of Ag to be used decreases, it is the best method to recover the power of the module after use at a minimum cost and reuse the module itself. Economic recovery technology can be applied to the power degradation, caused by the resistive solder bond (RSB) hotspot by poor soldering, because the recovery process can be simplified compared to the power loss that is often greater than 30%. This study demonstrated a quick recovery of the RSB hotspot with on-site recovery technology applied with resin and verified the performance and long-term reliability of on-site recovery technology, compared to the factory recovery method, where the back sheet is removed and laminated to recover the module. Both the factory and field recovery methods confirmed recovery results closer to the initial rated power output of the samples. Each sample was degraded by the RSB hotspot to ~62–65% of the initial power output, and the recovery process successfully recovered it to ~96–99%. In on-site recovery, verification of the possible EVA solvothermal swelling, which is the effect of organic solvents contained in the resin on EVA, is essential for verifying the long-term reliability of the recovered module. In this study, the power degradations of the on-site recovered samples after a TC 200 cycle test are −2.14% and −0.95%, respectively, which are within the certification test standard of the new manufacturing module. Existing factory recovery costs not only in the recovery process, but also in a total of 22 stages, such as the transfer of the target module. The largest advantage is that the on-site recovery process can be restarted in the field after only eight stages.

Circular economy and zero-carbon strategies between Japan and South Korea: A comparative study

The global population is increasing, as is the demand for basic materials. At the same time, key resources are in short supply, and the extraction and use of raw materials have major environmental implications, for instance, increased CO₂ emission. In a Circular Economy (CE), resources and products are divided, leased, reused, repaired, refurbished, and recycled, extending product life cycles, reducing waste, and generating additional value. Government entities in Japan and South Korea are designing and implementing policies to facilitate the transition to a CE and achieve carbon neutrality. The paper compares Japanese policies and actions with those of South Korea, identifies challenges and options for improvements in each country, and lessons that they can share. The paper reviews CE and low carbon policies in the two countries and compares how those, but also public interest and initiatives differ between them. It provides recommendations to address observed shortcomings and capture opportunities to connect CE and zero-carbon strategies. The article is expected to interest Japanese and South Korean policy-makers, companies, and academics.

Estimating the Lifetime of Solar Photovoltaic Modules in Australia

Determining the lifetime of solar photovoltaic modules is integral to planning future installations and ensuring effective end-of-life management. The lifetime of photovoltaic modules is most commonly considered to be 25 years based on performance guarantees of 80% power output after 25 years of operation; however, influences including climatic conditions, social behaviour, fiscal policy, and technological improvements have the potential to prompt early replacement. Therefore, this work aims to estimate the operating lifetime of photovoltaic panels more accurately in Australia by considering a variety of technical, economic, and social reasons for decommissioning. Based on a range of sources including government organisations, other policymakers, regulators and advisors, energy suppliers, researchers, recyclers, and manufacturers, three lifetime models—power decrease, damage and technical failures, and economic motivation—were developed and then weighted in three scenarios to form overall views of panel lifetime in Australia. In addition, it was concluded that the module lifetime will vary considerably between countries due to differences in market factors. Therefore, these results specifically address Australia as most of the input data were sourced from Australian industry reports and Australian photovoltaic systems and interpreted within the context of the Australian photovoltaic market. However, the methodology of estimating lifetime based on both technical and non-technical factors can be applied to other scenarios by using country-specific data. With the popularity of photovoltaic technology beginning in the early 2010s and given the practical lifetimes of 15–20 years found in this work, Australia will need to act swiftly within the next three years to responsibly manage the looming solar panel waste.

PV in the circular economy, a dynamic framework analyzing technology evolution and reliability impacts

Rapid, terawatt-scale deployment of photovoltaic (PV) modules is required to decarbonize the energy sector. Despite efficiency and manufacturing improvements, material demand will increase, eventually resulting in waste as deployed modules reach end of life. Circular choices for decommissioned modules could reduce waste and offset virgin materials. We present PV ICE, an open-source python framework using modern reliability data, which tracks module material flows throughout PV life cycles. We provide dynamic baselines capturing PV module and material evolution. PV ICE includes multimodal end of life, circular pathways, and manufacturing losses. We present a validation of the framework and a sensitivity analysis. Results show that manufacturing efficiencies strongly affect material demand, representing >20% of the 9 million tons of waste cumulatively expected by 2050. Reliability and circular pathways represent the best opportunities to reduce waste by 56% while maintaining installed capacity. Shorter-lived modules generate 81% more waste and reduce 2050 capacity by 6%.

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PV ICE is an open-source tool that evaluates circular paths for photovoltaics

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Features material flow tracking for waste, virgin needs, and installed capacity

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Dynamic baselines of historic and projected c-Si PV data are provided

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Sensitivity analysis shows increasing PV lifetime reduces material requirements

Life Cycle Assessment of Solar Photovoltaic in India: A Circular Economy Approach

This pioneering work employs the attributional and comparative life cycle assessment methodology to evaluate India's ambitious target of installing 100 GW of solar energy by 2022 and the FRELP method to study the circular economy prospects of the substantial PV waste it is expected to generate. Business as usual projections suggest that the intended target will be achieved no sooner than 2029. The lower lifetime of polycrystalline PV modules combined with their lower efficiency is found to severely downgrade their environmental performance vis-à-vis monocrystalline PV modules. The end-of-life treatment of the projected 6,576 tonnes of solar PV waste, expected to be accumulated between 2034-59, indicates a recovery rate of 90.7% entailing electricity consumption, GHG emissions, and monetary cost of 678.6 MWh, 648 tonnes of CO2 eq., and USD 11.8 billion, respectively. Simultaneously, the recovery of aluminum and glass alone leads to a direct saving of 70.3 GWh of energy by eliminating raw material extraction and processing. Further, the economic value of the recovered material at USD 11.74 billion is found to have the potential to generate additional solar capacity worth 19 GW. However, making the end-of-life treatment of PV waste financially feasible would require government subsidization. A minimum amount that would equate the costs to the benefits is USD 690/MW. The study, therefore, intends to inform potential stakeholders about the environmental burden as well as the economic potential of the impending PV waste and concludes with important policy prescriptions for enabling a sustainable energy transition through the circular economy approach.

Overview of global status and challenges for end-of-life crystalline silicon photovoltaic panels: A focus on environmental impacts

Recent developments in photovoltaic (PV) technology have enabled a reduction of fossil fuel usage and subsequent carbon dioxide (CO₂) release from energy production. However, end-of-life (EoL) crystalline silicon (c-Si) PV panels have become an emerging waste issue. This overview attempts to update and forecast the global status of renewable energy capacity and c-Si PV waste generation under different scenarios and to present a summary of the recent literature on recycling technologies and life cycle assessment (LCA) of EoL c-Si PV panels with a focus on reclaimable resources. For most LCA studies in the 1980s and the 2000s, the EoL phase of PV systems has often neglected or oversimplified (e.g., disposal after low-rate recovery) the fact that various recycling procedures and reclaimable resources from each stage cannot be appropriately considered. A limited number of studies have been available since the 2010s that highlight the high-rate recovery from EoL PV panels. However, the differences in functional unit, system boundary and impact analysis methodology make it difficult to compare the results directly, and spatio-temporal uncertainties are yet to be thoroughly quantified due to the lack of workable localized data. More efforts are needed to identify complementary environmental impacts (i.e., burden and credit) from the individual recycling processes. Correspondingly impacts from transport need to be fully incorporated for the optimization of the recycling process which has been neglected in most of the previous studies.

Weather Data Mixing Models for Day-Ahead PV Forecasting in Small-Scale PV Plants

As a large number of small-scale PV plants have been deployed in distribution systems, generation forecasting of such plants has recently been gaining interest. Because the PV power mainly depends on weather conditions, it is important to accurately collect weather data for relevant PV sites to enhance PV forecasting accuracy. However, small-scale PV plants do not often have their own measuring apparatus to get historical weather data, so they have used weather datasets from relatively nearby weather data centers (WDCs). Therefore, these small-scale PV plants have difficulty delivering robust and reliable forecasting accuracy because of inappropriate predicted weather data from a distance. In this paper, two weather data mixing models are proposed: (a) inverse distance weighting (IDW), and (b) inverse correlation weighting (ICW). These models acquire adequate mixed weather data for the day-ahead generation forecasting for small-scale PV plants. Furthermore, the mixed weather data are collected using the geographic distance between the PV site and WDCs, or correlation between the PV generation and weather variables from nearby WDCs. Interestingly, the proposed ICW model outperforms when WDCs are located distant from the PV plants, whereas IDW performs well with the closer WDCs. The forecasting performance of the proposed mixing models was compared with those of the existing weather data collection methods.

Towards Improved Circular Economy and Resource Security in South Korea

This study explores the importance of critical raw materials and minerals by analyzing the Republic of Korea’s recent circular economy and resource security policy. Raw materials and rare metals are becoming increasingly significant to the Korean economy because the country is currently shifting away from fossil fuels and nuclear power towards renewable energy resources as well as transforming its industries towards decarbonization, digitization, and automation. Korea is a resource-poor country and is heavily dependent on imported minerals and rare earths, which are essential for its economy and new industry. Responding to these challenges and concerns, Korea is moving towards a sustainable circular economy and achieving greater resource security. Despite certain limitations, this transition would ultimately contribute in preparing Korea for current and future challenges in the areas of critical raw materials and minerals.

PV Waste Thermal Treatment According to the Circular Economy Concept

Photovoltaic panels (PV) are one of the most popular technological solutions used to produce green renewable energy. They are known as green technology, but by analyzing a life cycle of a common panel, we can find out that production of these panels is strictly associated with generation of a large waste stream. PV modules are constantly modified and, therefore, it is required to consider the impact of the applied materials on the environment during the whole lifecycle of the product. The most important aspect of the assessment of a life cycle of a photovoltaic module in the phase of decommissioning is material recycling. The process of material recycling is very difficult, due to the lamination used in the currently exploited technology. This paper presents the results of pyrolysis for a sample of a silicon module. The results of the presented research show a weight loss of 48.16 in case of the tested samples. This paper presents the outcome of a quantitative analysis of the content of polycyclic aromatic for liquid and concentrations of Br, Cl and F for a gaseous fraction of pyrolysis products. The goal of the research presented in the paper was to find the optimal parameters for thermal separation, as well as the influence of the energy consumption and materials separation efficiency on the final thermal efficiency of the process.

Optimal Parameters of Volt–Var Function in Smart Inverters for Improving System Performance

This paper proposes a method to improve the performance of a distribution system by optimizing volt–var function of a smart inverter to alleviate the voltage deviation problem due to distributed generation connection. In order to minimize voltage deviation and line losses which represent the performance of a distribution system, this paper proposes an algorithm that optimally sets the parameters of the volt–var function. In the process of optimizing the parameters of the volt–var function, the algorithm proposed in this paper considers minimizing the contribution of the reactive power in order not to affect the output of the distributed generation. In order to apply to the field, the distribution system in South Korea considering the configuration and operation regulation was selected as a test model for algorithm verification. As a result, the system performance was successfully improved by optimally setting the volt–var function of the smart inverter which is an effective way to solve the over-voltage problem caused by distributed generation connection. This paper verified the proposed method through OpenDSS, a quasi-static time-series simulation, for the test model considering the characteristics of the distribution system in South Korea.