Ecodesign of large-scale photovoltaic (PV) systems with multi-objective optimization and Life-Cycle Assessment (LCA)

Because of the increasing demand for the provision of energy worldwide and the numerous damages caused by a major use of fossil sources, the contribution of renewable energies has been increasing significantly in the global energy mix with the aim at moving towards a more sustainable development. In this context, this work aims at the development of a general methodology for designing PV systems based on ecodesign principles and taking into account simultaneously both techno-economic and environmental considerations. In order to evaluate the environmental performance of PV systems, an environmental assessment technique was used based on Life Cycle Assessment (LCA). The environmental model was successfully coupled with the design stage model of a PV grid-connected system (PVGCS). The PVGCS design model was then developed involving the estimation of solar radiation received in a specific geographic location, the calculation of the annual energy generated from the solar radiation received, the characteristics of the different components and the evaluation of the techno-economic criteria through Energy PayBack Time (EPBT) and PayBack Time (PBT). The performance model was then embedded in an outer multi-objective genetic algorithm optimization loop based on a variant of NSGA-II. A set of Pareto solutions was generated representing the optimal trade-off between the objectives considered in the analysis. A multi-variable statistical method (i.e., Principal Componet Analysis, PCA) was then applied to detect and omit redundant objectives that could be left out of the analysis without disturbing the main features of the solution space. Finally, a decision-making tool based on M-TOPSIS was used to select the alternative that provided a better compromise among all the objective functions that have been investigated. The results showed that while the PV modules based on c-Si have a better performance in energy generation, the environmental aspect is what makes them fall to the last positions. TF PV modules present the best trade-off in all scenarios under consideration. A special attention was paid to recycling process of PV module even if there is not yet enough information currently available for all the technologies evaluated. The main cause of this lack of information is the lifetime of PV modules. The data relative to the recycling processes for m-Si and CdTe PV technologies were introduced in the optimization procedure for ecodesign. By considering energy production and EPBT as optimization criteria into a bi-objective optimization cases, the importance of the benefits of PV modules end-of-life management was confirmed. An economic study of the recycling strategy must be investigated in order to have a more comprehensive view for decision making

Multiobjective optimization of large scale photovoltaic (PV) systems design: Technico-economic and life-cycle assessment considerations

Solar energy systems are a source of "clean" energy. Yet, if power generation from photovoltaic (PV) systems is free from fossil fuel use and greenhouse gas (GHG) emissions, a considerable amount of energy is consumed in the manufacturing and transport of the elements of the system. Silicon is currently the most widely used material for solar cell design. In this context, life cycle assessment (LCA) studies play a major role to compare and analyze the environmental impacts of products and services along their life cycle. This work aims at determining a general methodology for designing large scale photovoltaic systems, taking into account both technico-economic and environmental considerations. In this paper, only the environmental issue tackled by Life Cycle Assessment has been implemented to quantify the environmental impacts related to three technology of crystalline silicon for photovoltaic modules (PV) that are monocrystalline, multicrystalline and ribbon silico

A Multi-objective Framework for Assessment of Recycling Strategies for Photovoltaic Modules based on Life Cycle Assessment

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

Écoconception de systèmes photovoltaïques (PV) à grande échelle par optimisation multi-objectif et Analyse du Cycle de Vie (ACV)

En raison de la demande croissante d énergie dans le monde et des nombreux dommages causés par l utilisation des énergies fossiles, la contribution des énergies renouvelables a augmenté de manière significative dans le mix énergétique global dans le but de progresser vers un développement plus durable. Dans ce contexte, ce travail vise à l élaboration d une méthodologie générale pour la conception de systèmes photovoltaïques, basée sur les principes d écoconception, en tenant compte simultanément des considérations technico-économiques et environnementales. Afin d évaluer la performance environnementale des systèmes PV, une technique d évaluation environnementale basée sur l Analyse du Cycle de Vie (ACV) a été utilisée. Le modèle environnemental a été couplé d une manière satisfaisante avec le modèle de conception d un système PV connecté au réseau pour obtenir un modèle global, apte à un traitement par optimisation. Le modèle de conception du système PV résultant a été développé en faisant intervenir l estimation du rayonnement solaire reçu dans une zone géographique concernée, le calcul de la quantité annuelle d énergie produite à partir du rayonnement solaire reçu, les caractéristiques des différents composants et l évaluation des critères technico-économiques à travers le temps de retour énergétique et le temps de retour sur investissement. Le modèle a ensuite été intégré dans une boucle d optimisation multi-objectif externe basée sur une variante de l algorithme génétique NSGA-II. Un ensemble de solutions du Pareto a été généré représentant le compromis optimal entre les différents objectifs considérés dans l analyse. Une méthode basée sur une Analyse en Composantes Principales (ACP) est appliquée pour détecter et enlever les objectifs redondants de l analyse sans perturber les caractéristiques principales de l espace des solutions. Enfin, un outil d aide à la décision basé sur M- TOPSIS a été utilisé pour sélectionner l option qui offre un meilleur compromis entre toutes les fonctions objectifs considérées et étudiées. Bien que les modules photovoltaïques à base de silicium cristallin (c-Si) ont une meilleure performance vis-à-vis de la production d énergie, les résultats ont montré que leur impact environnement est le plus élevé des filières technologiques de production de panneaux. Les technologies en couches minces présentent quant à elles le meilleur compromis dans tous les scénarios étudiés. Une attention particulière a été accordée aux processus de recyclage des modules PV, en dépit du peu d informations disponibles pour toutes les technologies évaluées. La cause majeure de ce manque d information est la durée de vie relativement élevée des modules photovoltaïques. Les données relatives aux procédés de recyclage pour les technologies basées sur CdTe et m-Si sont introduites dans la procédure d optimisation par l écoconception. En tenant compte de la production d énergie et du temps de retour sur énergie comme critères d optimisation, l avantage de la gestion de fin de vie des modules PV a été confirmé. Une étude économique de la stratégie de recyclage doit être considérée et étudiée afin d avoir une vision plus globale pour la prise de décision.Because of the increasing demand for the provision of energy worldwide and the numerous damages caused by a major use of fossil sources, the contribution of renewable energies has been increasing significantly in the global energy mix with the aim at moving towards a more sustainable development. In this context, this work aims at the development of a general methodology for designing PV systems based on ecodesign principles and taking into account simultaneously both techno-economic and environmental considerations. In order to evaluate the environmental performance of PV systems, an environmental assessment technique was used based on Life Cycle Assessment (LCA). The environmental model was successfully coupled with the design stage model of a PV grid-connected system (PVGCS). The PVGCS design model was then developed involving the estimation of solar radiation received in a specific geographic location, the calculation of the annual energy generated from the solar radiation received, the characteristics of the different components and the evaluation of the techno-economic criteria through Energy PayBack Time (EPBT) and PayBack Time (PBT). The performance model was then embedded in an outer multi-objective genetic algorithm optimization loop based on a variant of NSGA-II. A set of Pareto solutions was generated representing the optimal trade-off between the objectives considered in the analysis. A multi-variable statistical method (i.e., Principal Componet Analysis, PCA) was then applied to detect and omit redundant objectives that could be left out of the analysis without disturbing the main features of the solution space. Finally, a decision-making tool based on M-TOPSIS was used to select the alternative that provided a better compromise among all the objective functions that have been investigated. The results showed that while the PV modules based on c-Si have a better performance in energy generation, the environmental aspect is what makes them fall to the last positions. TF PV modules present the best trade-off in all scenarios under consideration. A special attention was paid to recycling process of PV module even if there is not yet enough information currently available for all the technologies evaluated. The main cause of this lack of information is the lifetime of PV modules. The data relative to the recycling processes for m-Si and CdTe PV technologies were introduced in the optimization procedure for ecodesign. By considering energy production and EPBT as optimization criteria into a bi-objective optimization cases, the importance of the benefits of PV modules end-of-life management was confirmed. An economic study of the recycling strategy must be investigated in order to have a more comprehensive view for decision making.TOULOUSE-INP (315552154) / SudocSudocFranceF

Combining Multi-Objective Optimization, Principal Component Analysis and Multiple Criteria Decision Making for ecodesign of photovoltaic grid-connected systems

Photovoltaic grid-connected systems (PVGCS) promise to be a major contributor of the future global energy system. Even if no GreenHouse Gases (GHG) are emitted during their operation phase, emissions are generated by the use of fossil fuel-based energy during the manufacture, building and recycling of the components. An integrated ecodesign framework that simultaneously manages technical, economic and environmental criteria for the design and sizing of PVGCS (cradle-to-gate approach) is presented in this work. A Multi-Objective Optimization problem embedded in an external multi-objective Genetic Algorithm (NGSA II) optimization loop generates a set of Pareto solutions representing the optimal trade-off between the objectives considered. Then a decision-making tool (M-TOPSIS) selects the solution providing the best compromise. The Life Cycle Assessment (LCA) method was selected to assess the environmental impact. Five commercial PV technologies were evaluated to generate alternatives of PVGCS configurations through a set of 18 objectives (two technical and one economic criteria as well as the 15 midpoint categories of the IMPACT 2002+ method). After a statistical analysis of the first results, the Principal Component Analysis (PCA) method was applied to remove redundant objectives, thus leading to only four contradictory objectives. The results highlight the advantage of the use of thin-film PV modules over crystalline-Si based PV modules

Écoconception de systèmes photovoltaïques (PV) à grande échelle par optimisation multi-objectif et Analyse du Cycle de Vie (ACV)

En raison de la demande croissante d’énergie dans le monde et des nombreux dommages causés par l’utilisation des énergies fossiles, la contribution des énergies renouvelables a augmenté de manière significative dans le mix énergétique global dans le but de progresser vers un développement plus durable. Dans ce contexte, ce travail vise à l’élaboration d’une méthodologie générale pour la conception de systèmes photovoltaïques, basée sur les principes d’écoconception, en tenant compte simultanément des considérations technico-économiques et environnementales. Afin d’évaluer la performance environnementale des systèmes PV, une technique d’évaluation environnementale basée sur l’Analyse du Cycle de Vie (ACV) a été utilisée. Le modèle environnemental a été couplé d’une manière satisfaisante avec le modèle de conception d’un système PV connecté au réseau pour obtenir un modèle global, apte à un traitement par optimisation. Le modèle de conception du système PV résultant a été développé en faisant intervenir l’estimation du rayonnement solaire reçu dans une zone géographique concernée, le calcul de la quantité annuelle d’énergie produite à partir du rayonnement solaire reçu, les caractéristiques des différents composants et l’évaluation des critères technico-économiques à travers le temps de retour énergétique et le temps de retour sur investissement. Le modèle a ensuite été intégré dans une boucle d’optimisation multi-objectif externe basée sur une variante de l’algorithme génétique NSGA-II. Un ensemble de solutions du Pareto a été généré représentant le compromis optimal entre les différents objectifs considérés dans l’analyse. Une méthode basée sur une Analyse en Composantes Principales (ACP) est appliquée pour détecter et enlever les objectifs redondants de l’analyse sans perturber les caractéristiques principales de l’espace des solutions. Enfin, un outil d’aide à la décision basé sur M- TOPSIS a été utilisé pour sélectionner l’option qui offre un meilleur compromis entre toutes les fonctions objectifs considérées et étudiées. Bien que les modules photovoltaïques à base de silicium cristallin (c-Si) ont une meilleure performance vis-à-vis de la production d’énergie, les résultats ont montré que leur impact environnement est le plus élevé des filières technologiques de production de panneaux. Les technologies en « couches minces » présentent quant à elles le meilleur compromis dans tous les scénarios étudiés. Une attention particulière a été accordée aux processus de recyclage des modules PV, en dépit du peu d’informations disponibles pour toutes les technologies évaluées. La cause majeure de ce manque d’information est la durée de vie relativement élevée des modules photovoltaïques. Les données relatives aux procédés de recyclage pour les technologies basées sur CdTe et m-Si sont introduites dans la procédure d’optimisation par l’écoconception. En tenant compte de la production d’énergie et du temps de retour sur énergie comme critères d’optimisation, l’avantage de la gestion de fin de vie des modules PV a été confirmé. Une étude économique de la stratégie de recyclage doit être considérée et étudiée afin d’avoir une vision plus globale pour la prise de décision.Because of the increasing demand for the provision of energy worldwide and the numerous damages caused by a major use of fossil sources, the contribution of renewable energies has been increasing significantly in the global energy mix with the aim at moving towards a more sustainable development. In this context, this work aims at the development of a general methodology for designing PV systems based on ecodesign principles and taking into account simultaneously both techno-economic and environmental considerations. In order to evaluate the environmental performance of PV systems, an environmental assessment technique was used based on Life Cycle Assessment (LCA). The environmental model was successfully coupled with the design stage model of a PV grid-connected system (PVGCS). The PVGCS design model was then developed involving the estimation of solar radiation received in a specific geographic location, the calculation of the annual energy generated from the solar radiation received, the characteristics of the different components and the evaluation of the techno-economic criteria through Energy PayBack Time (EPBT) and PayBack Time (PBT). The performance model was then embedded in an outer multi-objective genetic algorithm optimization loop based on a variant of NSGA-II. A set of Pareto solutions was generated representing the optimal trade-off between the objectives considered in the analysis. A multi-variable statistical method (i.e., Principal Componet Analysis, PCA) was then applied to detect and omit redundant objectives that could be left out of the analysis without disturbing the main features of the solution space. Finally, a decision-making tool based on M-TOPSIS was used to select the alternative that provided a better compromise among all the objective functions that have been investigated. The results showed that while the PV modules based on c-Si have a better performance in energy generation, the environmental aspect is what makes them fall to the last positions. TF PV modules present the best trade-off in all scenarios under consideration. A special attention was paid to recycling process of PV module even if there is not yet enough information currently available for all the technologies evaluated. The main cause of this lack of information is the lifetime of PV modules. The data relative to the recycling processes for m-Si and CdTe PV technologies were introduced in the optimization procedure for ecodesign. By considering energy production and EPBT as optimization criteria into a bi-objective optimization cases, the importance of the benefits of PV modules end-of-life management was confirmed. An economic study of the recycling strategy must be investigated in order to have a more comprehensive view for decision making

NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics

Xenarthrans—anteaters, sloths, and armadillos—have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, 10 anteaters, and 6 sloths. Our data set includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the southern United States, Mexico, and Caribbean countries at the northern portion of the Neotropics, to the austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n = 5,941), and Cyclopes sp. have the fewest (n = 240). The armadillo species with the most data is Dasypus novemcinctus (n = 11,588), and the fewest data are recorded for Calyptophractus retusus (n = 33). With regard to sloth species, Bradypus variegatus has the most records (n = 962), and Bradypus pygmaeus has the fewest (n = 12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other data sets of Neotropical Series that will become available very soon (i.e., Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans data set. Please cite this data paper when using its data in publications. We also request that researchers and teachers inform us of how they are using these data