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A material flow model for the production of Bifacial Selective Emitter 60-cell p-type Cz PERC (Passivated Emitter and Rear Contacted) glass-backsheet modules with aluminium frame was built. The selected module represents mature technologies in the PV industry and their manufacturing is considered to take place in China in a production cluster with an annual module capacity of 5 GWp. In a first step, data acquisition and validation for wafer, cell and module fabs took place. The data were used to generate the reference system lifecycle inventories (LCI) and extended waste databases for the reference wafers, cells and modules. A set of potential circularity actions, such as the vertical integration of the operations and waste revalorisation strategies, had been proposed and their environmental performance and cost assessed by means of a life cycle assessment (LCA) and a total cost of ownership (TCO). Our results show that 87% of the waste can be reduced and revalorised, this represents a circular flow of raw materials of 18,756 Mg per year from a 5GWp PV module production cluster. Environmental impact reductions of 0.6–2.3% are estimated for different impact categories. We also estimate a cost reduction potential of 2.59% from total module costs.

A product made from virgin raw materials that ends up in a landfill presents a linear supply chain model. Today's photovoltaic (PV) industry is still largely based on this model. With the increasing volume of production, the raw materials required for it, and consequently the volume of waste, the application of circular economy principles in the PV sector can significantly increase its environmental efficiency. This study analyzes the impact of circularity on the supply chain of PV silicon used for PV module production. Four scenarios based on the combination of technological pathways and circularity options are created. Their evaluation is carried out by the methodologies of Material Circularity Indicator (MCI) and Life Cycle Assessment (LCA). The State-of-art case of the PV polysilicon supply chain corresponds to the MCI score of 0.54. Closed-loop circularity solutions provide the MCI score of 0.80 presenting the potential for a circular economy approach in the industry. LCA results show the reduction of environmental impact by 12% with improved circularity. The study presents the benefits of potential circularity options within the supply chain as well as the impact of technological development on the polysilicon demand.

With an increasing shift away from fossil fuels toward renewable energy sources within the European Union (EU), photovoltaics (PV) are projected to see substantial growth with estimates of nearly 600 GWp of capacity by 2030. As the use of PV technology continues to expand, the European Commission has introduced various policy instruments, enabling consumers to make informed choices. Among those, the Ecodesign directive 2009/125/EC sets a carbon footprint threshold as a minimum qualification for the European market to cut out the least sustainable PV modules. For this directive, the methodological guidelines for the complex carbon footprint calculation of PV modules are under development. To this end, this analysis compares the two methodologies, namely Electronic Product Environmental Assessment Tool (EPEAT) and the Ecodesign adaptation of Product Environmental Footprint Category Rules (PEFCR), emphasizing the implications of choosing one over the other for the PV industry. This study illustrates how varying parameters, like module lifetime, degradation rate, and purchased renewable electricity certificate allowance limit, stemming from the differing methodological approaches can influence the carbon footprint calculation. Apart from the strengths and weaknesses of each methodology, this article emphasizes the need for globally harmonized standards to ensure consistency in evaluating the carbon footprint of PV modules. The observations made in this study should be considered not just for Ecodesign directive but for any such market regulation policy like the recently passed EU Net Zero Industry Act or the EU Ecolabel for PV modules. It underlines the significance of choosing a transparent and fair approach to ensure the credibility of carbon footprint labels and meet the EU's decarbonization objectives successfully, propelling the transition toward a more sustainable energy landscape. [ABSTRACT FROM AUTHOR]

The large-scale deployment of photovoltaics (PV) is a central pillar in decarbonizing energy systems and reaching climate goals. Although PV is inherently associated to environmental awareness, it is not immune to reputational risks nor exempt of a responsibility for transparency and sustainability leadership. So far, advances in the PV industry have mainly been shaped by cost-reduction targets. We identified in previous works 16 topics where the PV sector comes short in addressing the United Nations Sustainable Development Goal 12 (SDG 12) “Ensure sustainable consumption and production patterns”. In this paper, practical approaches to address each of these sustainability gaps are proposed. The best-practices identified cover all aspects of sustainability as defined by SDG 12–from resource use and hazardous substances through corporate reporting and risk assessment to due diligence and waste management. Insights on methodological needs to improve sustainability assessment and accounting in PV are also provided. The compiled list of actions needed, although not intended to be exhaustive, constitutes a starting point for stakeholders to raise their ambitions and achieve more sustainability in PV value chains.

The tunneling oxide passivating contact (TOPCon) solar cell concept is one of the most promising ways to realize carrier-selective contacts, as it offers an evolutionary upgrade to today's mainstream PERC. Currently, the PV industry is looking into different technologically feasible options for transferring this cell concept from laboratory research to industrial manufacturing. This paper gives an overview of the technological maturity of various TOPCon approaches with the goal of achieving the most cost-effective, resource-conserving and mass-production-capable implementation. [ABSTRACT FROM AUTHOR]

To unlock the full potential of perovskite–silicon tandem solar cells with >30% efficiency at presumably low cost, the transparent conductive oxides (TCOs) and metal grid at the front side need to be adapted compared to classical silicon heterojunction (SHJ) solar cells. By means of optical and electrical modelling, we consider the main aspects to optimize the front electrode for the tandem case, where in contrast to silicon single junction devices, there are (i) different optical properties including a lower refractive index of the perovskite absorber (ii) about half the current, thus quarter the resistive power losses for the same series resistance contribution (iii) lateral transport at the front needs to be provided solely by the front TCO layer and (iv) lower thermal stability of the perovskite, which affects TCO deposition conditions and results in a less efficient sintering of the silver screen printing pastes. This study concludes that compared to silicon heterojunction cells, the thickness of the front TCO should be reduced from 75 nm to around 20 nm, resulting in less parasitic absorption and a potential cost reduction of 1.46 €ct/cell for ITO. We investigate the impact of different front metallization including plating and silver screen printing and showcase that for multi‐wire interconnection concepts, the number of wires can be reduced from 18 wires to 9 or even less depending on the front metallization. Finally, we give an outlook on the silver consumption and levelized cost of electricity. [ABSTRACT FROM AUTHOR]

The development of new ways of increasing the production throughput for passivated emitter and rear cells (PERCs), as the major solar cell technology in the global market, is an area of great interest to the PV community. This paper presents approaches for significantly increasing the throughput of PERC production processes. The main focus is on the tube furnace processes for the emitter formation and oxidation, with the introduction of the High Temperature Stack Oxidation (HiTSOx) approach. Additional approaches that are currently under investigation at Fraunhofer ISE for increasing the throughput for wet-chemical, printing and laser processes will also be briefly outlined. [ABSTRACT FROM AUTHOR]

Perovskite–silicon tandem solar cells have shown a rapid progress within the past 5 years in terms of their research cell efficiency and are currently being investigated as candidates for the next generation of industrial PV devices. This raises the question of which silicon bottom cell will be most suitable for tandem application. Currently, the silicon heterojunction (SHJ) technology dominates in tandem research achieving world records. However, it is an open issue of how to transfer these research results to industrial mass production, which is driven by cost reduction and resource efficiency and includes challenges like upscaling and long‐term stability. Therefore, it is highly relevant for the PV industry to get reliable and predictive estimates on the efficiency and cost potential, as well as technologically feasible solutions. In this work, we elaborate on silicon bottom cell concepts based on the PERC, TOPCon, and SHJ technology combined with two different interconnection concepts. For each tandem device, the efficiency potential is investigated by means of an experimentally validated simulation model. Second, we evaluate the bottom cell concepts in terms of all‐in cell costs per piece. Bringing the efficiency potential and cost evaluation together allows us to assess the different tandem cell concepts in terms of all‐in module cost per watt peak. Our results show that perovskite–silicon tandem devices are promising candidates to significantly reduce the levelized cost of electricity and, in particular, that the "race" for the best silicon bottom cell is still open to all the investigated bottom cell technologies. [ABSTRACT FROM AUTHOR]

To embrace the terawatt-scale challenge of the PV market growth, a low-carbon and resource-efficient pathway has to be guaranteed. An approach for doing this is to enable market mechanisms that account for the greenhouse gases emissions, and their associated costs, from PV systems and components. Under such conditions, it is expected that different technological options and solutions will have to be considered for the development and deployment of PV power plants and systems. In this paper, the economic competitiveness and environmental performance of the production of PV systems in Europe and China are assessed. Results are presented for the currently dominant recharged Czochralski (Cz) wafer technology, and for the less energy-intensive seed manipulation for artificially controlled defect technique (SMART) cast-mono (CM) technology. The analysis shows that SMART technology can be used to produce mono PERC systems with a climate change impact of just 21.63g CO2-eq/kWh, while a Cz PERC system produced in China will entail an emission of 43.32g CO2-eq/kWh. Around 45% of this reduction is achieved by having the production located in Europe. SMART technology yields a reduction potential of 9% of the associated global warming potential (GWP), when compared with the more energyintensive Cz growth technology. Both Cz and SMART technologies can be produced at a competitive cost in Europe when carbon-associated costs are taken into consideration, leading to total costs of ownership of 21.5 and 21.6€ct/Wp respectively. [ABSTRACT FROM AUTHOR]