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37th European Photovoltaic Solar Energy Conference and Exhibition; 1148-1154, The current worldwide market share of bifacial solar modules is around 10% in 2020 and is expected to increase to at least to 35% in 2030 [1]. Fundamental cell and module designs for bifacial PV exist but there is still a strong need for the development of dedicated module designs that are optimized in improved energy yield and of LCOE. To shape this development, work is conducted on optimization of bifacial solar modules with improved bifacial solar cells featuring highest bifaciality factors. Besides module development it is essential to improve the corresponding measurement procedures and tools for energy harvest calculation. In the successfully completed international Solar-era.net project “BiFaLo” the complete value chain was considered, starting with cell and module development, reliability studies, indoor and outdoor measurement campaigns and energy yield modelling. This paper will focus on module design and energy yield evaluation of outdoor measurements at three locations (Halle & Konstanz (Germany), Jerusalem (Israel)) to examine the variables that influence the gain of bifacial modules to determine and qualify improved module designs.

The present study examined measurement invariance and convergent validity of a novel vignette-based measure of emotion-specific self-regulation that simultaneously assesses attributional bias, emotion-regulation, and self-efficacy beliefs about emotion regulation. Participants included 541 youth–mother dyads from three countries (Italy, the United States, and Colombia) and six ethnic/cultural groups. Participants were 12.62 years old ( SD = 0.69). In response to vignettes involving ambiguous peer interactions, children reported their hostile/depressive attribution bias, self-efficacy beliefs about anger and sadness regulation, and anger/sadness regulation strategies (i.e., dysregulated expression and rumination). Across the six cultural groups, anger and sadness self-regulation subscales had full metric and partial scalar invariance for a one-factor model, with some exceptions. We found support for both a four- and three-factor oblique model (dysregulated expression and rumination loaded on a second-order factor) for both anger and sadness. Anger subscales were related to externalizing problems, while sadness subscales were related to internalizing symptoms.

Introduzione Le competenze di regolazione emotiva sono quei processi utilizzati per gestire e modificare modalità e intensità nello sperimentare le emozioni, e gli stati motivazionali e fisiologici ad esse collegate, così come la loro espressione comportamentale (Eisenberg, et al. 2014). In ambito scolastico, l’approccio Social Emotional Learning (CASEL, 2003) ha individuato obiettivi e metodologie per l’implementazione di programmi finalizzati alla promozione delle competenze emotive e sociali. Un cospicuo corpus di ricerche ha documentato l’efficacia dei programmi SEL nel migliorare l’atteggiamento verso la scuola, nel promuovere comportamenti prosociali, nel favorire il successo scolastico e nel ridurre i comportamenti aggressivi, il disagio psicologico e l’uso di sostanze in adolescenza (Durlak et al., 2011; Greenberg et al., 2003; January et al., 2011; Zins, Weissberg, Wang, & Walberg, 2004). Nel contesto italiano diversi contributi di ricerca e intervento hanno avvalorato l’efficacia di programmi di intervento attuati nei contesti educativi sia in età scolare che pre-scolare (Grazzani, Ornaghi, & Antoniotti, 2011; Ornaghi, Brockmeier, Grazzani, 2014). Il presente studio esamina l’efficacia di un programma per la scuola elementare per lo sviluppo delle abilità di regolazione emotiva, basato sul principio ispiratore del PATHS (Promoting Alternative Thinking Strategies: Greenberg & Kusché, 1993). L’intervento è stato articolato in 15 unità laboratoriali manualizzate, per una durata complessiva di sei mesi, allo svolgimento delle quali gli insegnanti erano stati opportunamente formati. Durante l’intervento erano previste sessioni di supervisione e di confronto fra pari. Metodo Hanno partecipato alla ricerca-intervento 9 classi seconde della scuola primaria, per un totale di 200 alunni. Il disegno di ricerca ha previsto un gruppo di intervento, composto da 6 classi (118 alunni) e un gruppo di controllo, composto da 4 classi (82 alunni). I genitori hanno fornito il loro consenso scritto alla partecipazione dei figli all’intervento e sono stati coinvolti mediante un incontro introduttivo in cui sono stati presentati gli obiettivi principali del programma di intervento. D’accordo con la scuola, alle classi del gruppo di controllo è stata offerta l’opportunità di partecipare a programmi analoghi nei successivi anni scolastici. Per la valutazione pre/post è stata adottata una metodologia multi-informant: insegnante, osservatori (tirocinanti del Corso di Laurea in Scienze dell’educazione), genitori, gli stessi alunni - Emotion Regulation Checklist (Shields & Cicchetti, 1997; validazione italiana di Molina, Sala, Zappulla, et al, 2014), che comprende 24 item abilità di regolazione emotiva (1= quasi mai a 4= quasi sempre). - Indicatori della Capacità di Adattamento Sociale in Età Evolutiva (Caprara, Pastorelli, Barbaranelli, Vallone, 1992). Nello studio è stata utilizzata la Scala del Comportamento Prosociale, composta da 13 item per valutare la propensione a manifestare comportamenti di aiuto, a promuovere iniziative rivolte ad altri e a condividere oggetti ed esperienze (1= mai a 3= tante volte). Risultati I risultati preliminari delle ANOVA a misure ripetute hanno evidenziato interazioni significative gruppo x tempo: in particolare, gli alunni del gruppo di intervento mostrano un decremento nella labilità/negatività emotiva (F = 5,92; p ,016) e un incremento nella regolazione emotiva (F 6,19; p ,014] e nella frequenza dei comportamenti prosociali (F = 5,58; p ,019) rilevati dagli osservatori. Conclusioni Tali risultati confermano l’efficacia di interventi strutturati per promuovere già dalla scuola primaria abilità di riconoscimento, comprensione e discussione sulle emozioni, anche ai fini della realizzazione di un clima di classe prosociale.

33rd European Photovoltaic Solar Energy Conference and Exhibition; 943-946, Photovoltaic and recombination characteristics of new generation bifacial solar cells are demonstrated. The cells were fabricated using 6" pseudo square wafers of 5 to 6 .cm single crystalline Cz p-Si. Their front efficiency is exceeding 20 % with back to front short circuit current ratio 89 - 92%. The design is characterized by high bulk minority carrier lifetime above 0.5 ms, not degraded during the fabrication process. Rear p+ layer was prepared by controllable doping process using preliminary deposited thin B contained solid layer. Effective back surface recombination is below 10 cm/s. Measured implied Voc values of the PERT structure exceeding 700 mV are evidencing the intrinsic potential of the structure to provide the cell efficiency far exceeding 22 %. Textured front surface in combination with smoothly etched back provides effective light trapping. The equivalent efficiency of a bifacial solar cell, which characterizes its energy generation capability, will achieve values in the range 23 – 27 % as a function of use conditions.

32nd European Photovoltaic Solar Energy Conference and Exhibition; 711-714, Boron doped BSF is a critically important factor in high efficiency p-Si bifacial solar cell design. Recombination losses represented as effective surface recombination, Seff, are evaluated by simulation and experimentally. For thick heavily doped p+ layers Seff is determined mainly by recombination inside the layer with positive effect of top over doped region. Spectral response analysis of n+-p-p+ solar cells with highly doped and deep BSF (~1.6 m) demonstrates a possibility of providing Seff of 75±20 cm/s without surface passivation. For thinner p+ layers surface recombination is a critical factor. n-Si wafers symmetrically doped by boron ion-implantation or by boron thermal diffusion were used for experimental validation of the simulated surface recombination contribution to Seff and its dependence on the charge trapped in the passivation layer. The recombination parameters of the samples were measured using the photoconductivity decay method.

Obiettivo: esaminare le relazioni tra le dimensioni proattiva e reattiva dell’aggressività, le manifestazioni overt e covert del narcisismo e gli stili di moral reasoning. Metodo: a un campione di 674 studenti medi superiori italiani (età media 15.5 anni DS = 2.1) sono state somministrate le versioni italiane delle seguenti misure: Reactive-Proactive Aggression Questionnaire, Narcissistic Personalità Inventory, Hypersensitive Narcissism Scale, Prosocial Reasoning Objective Measure. Le relazioni tra le variabili di interesse sono state analizzate attraverso analisi di correlazione, regressione lineare e modelli di mediazione. Risultati: Il ragionamento morale di tipo Edonistico è risultato significativamente correlato con entrambe le manifestazioni di aggressività e con gli aspetti overt del narcisismo. Inoltre, la relazione tra ragionamento morale Edonistico e aggressività è risultata mediata dal narcisismo di tipo overt. Conclusioni: Questi risultati suggeriscono che il ragionamento morale Edonistico, se parte di una inclinazione narcisistica più ampia, possa rappresentare un fattore di rischio in adolescenza per entrambe le dimensioni dell’aggressività Objective: Examining the relations among proactive and reactive dimensions of aggression, overt and covert manifestations of narcissism, and styles of moral reasoning. Method: 674 Italian adolescent high school students (mean age = 15.5 years, SD = 2.1 years) were administered the following measures: Reactive-Proactive Aggression Questionnaire, Narcissistic Personalità Inventory, Hypersensitive Narcissism Scale, Prosocial Reasoning Objective Measure. Relations among key variables were analyzed using correlation analyses, regression analyses, and mediation models. Results: Hedonistic moral reasoning was significantly correlated with manifestations of aggression, as well as with overt aspects of narcissism. Moreover, overt narcissism statistically mediated the relations between moral reasoning and both proactive and reactive dimensions of aggression. Conclusions: These findings suggested hedonistic moral reasoning may be a risk factor in adolescence for both proactive and reactive dimensions of aggression when it is part of a broader narcissistic disposition.

The present study examined the longitudinal relations of adolescents' self-reported ego-resiliency to their emotional self-efficacy beliefs in expressing positive emotions and in managing negative emotions as they moved into early adulthood. Participants were 239 females and 211 males with a mean age of 17 years (SD = .80) at T1, 19 years (SD = .80) at T2, 21 years (SD = .82) at T3, and 25 years (SD = .80) at T4. A four-wave cross-lagged regression model and mediational analyses were used. In a panel structural equation model controlling for the stability of the constructs, reciprocal relationships across time were found between ego-resiliency and emotional self-efficacy beliefs related to the expression of positive emotions and to the management of negative emotions. Moreover, the relation between ego-resiliency assessed at T1 and T3, and ego-resiliency assessed at T2 and T4, was mediated through emotional self-efficacy beliefs (at T2 and T3, respectively), and vice versa. The posited conceptual model accounted for a significant portion of variance in ego-resiliency and has implications for understanding the development of ego-resiliency.

29th European Photovoltaic Solar Energy Conference and Exhibition; 950-953, Combined thermal diffusion – ion implantation technology, which was extensively used for n+-p-p+ space Si cell fabrication, can be applied also for terrestrial cell production. Starting Si of both p- and n- conductivity types can be used. The drawback of B ion implantation as a doping process for p+ layer formation is the introduction of a defect layer behind the implanted layer that can result in additional recombination losses. The effect of 30 keV B ion implantation and subsequent annealing was studied. Back IQE analysis of n+-p-p+ cells reveals the main factors affecting the formation of the defect layer and its influence on solar cell base recombination. Among these factors are: implantation dose, starting Si parameters and injection level during the measurements. Decrease of implantation dose and increase of annealing temperature suppress the formation of the defect layer. Experiments with annealing temperature in the range 910 - 1015 oC were carried out. SiN cap layer as a tool for decrease of out- diffusion can be used for rminimizing the implantation dose. The depth profiles of electro active B atoms after annealing at high temperatures are quite deep, and due to the back junction n+-n-p+ cell design was found as preferable. This is demonstrated by simulation of front and back IQE of the cell confirmed by measurement results. According to simulation the effective surface recombination at n+-n high-low barrier can be improved by using high resistivity Si (above ~ 5 .cm). Thermal oxidation was tested as a relative simple and controllable process for the p+ layer passivation. The influence of the positive charge which is typical for a silicon oxide film was estimated. According to simulation, the surface doping concentration is the dominating parameter influencing the effective surface recombination. The charge in the passivation layer is not influencing significantly when surface doping concentration is relatively high (above ~1019 cm-3)

28th European Photovoltaic Solar Energy Conference and Exhibition; 1835-1838, Photovoltaic and recombination properties of bifacial solar cells are analyzed. The cells were fabricated in a pilot production line using 6" pseudosquare wafers of 3 to 6 .cm single crystalline Cz Si. Their front efficiency is in the range 18.1 – 18.8 % with back to front short circuit current ratio 74 - 79 %. The design is characterized by high bulk minority carrier lifetime 0.2 – 1 ms, not degraded during the fabrication process, when good starting wafers were used. Effective back surface recombination is in the range 55 - 95 cm/s. Light trapping due to high back internal reflection contributes to current improvement compared to a regular mono facial cell with Al alloyed back. Equivalent efficiency as a quality criteria of a bifacial solar cell is proposed. Routine adjustment of fabrication process promise the increase of average front efficiency above 19 % and equivalent efficiency above 24 %.

26th European Photovoltaic Solar Energy Conference and Exhibition; 3140-3143, I-V characteristics of bifacial and mono-facial modules in the test roof-top PV field in Jerusalem were monitored simultaneously. Analysis of factors affecting the energy gains due to contribution of bifacial module back is based on time-of-day, daily and monthly energy generation data. Among these factors: diffuse to global radiation ratio, season and time-of-day Sun position. Daily energy gain of an in-field bifacial vs. a mono-facial module at underlying surface albedo ~0.50 varies in the range 5 – 38 %. An evaluated equivalent efficiency of 21 % is based on the measured yearly gain for bifacial solar cells with a front efficiency 18 %. Optimization of the PV field design should increase these values.

25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 1805-1809, There are applications of solar cells under illumination conditions for lower than "one sun". Solar cell efficiency decreases with decreasing irradiance. Several factors affecting conversion efficiency at low irradiances (down to ~0.01 sun) are studied. Experiments were performed with bifacial n+-p-p+ Si solar cells, fabricated using an ion implantation procedure for BSF formation. Optimal resistivity of the starting Si is evaluated taking into consideration recombination in the ion induced defect layer. Use of high resistivity Si eliminates the influence of this defect layer on recombination in the base region. Lifetime dependence on injection level can cause current non linearity and therefore an additional efficiency drop at low irradiance. Light induced defects can be responsible for this effect. The quality of the p-n junction as expressed by the ideality factors of the two-diode model is one of the most important factors affecting solar cell conversion efficiency at low light intensities.