Building Integrated Photovoltaics (BIPV): Review, Potentials, Barriers and Myths

To date, none of the predictions that have been made about the emerging BIPV industry have really hit the target. The anticipated boom has so far stalled and despite developing and promoting a number of excellent systems and products, many producers around the world have been forced to quit on purely economic grounds. The authors believe that after this painful cleansing of the market, a massive counter trend will follow, enlivened and carried forward by more advanced PV technologies and ever-stricter climate policies designed to achieve energy neutrality in a cost-effective way. As a result, the need for BIPV products for use in construction will undergo first a gradual and then a massive increase. The planning of buildings with multifunctional, integrated roof and façade elements capable of fulfilling the technical and legal demands will become an essential, accepted part of the architectonic mainstream and will also contribute to an aesthetic valorisation. Until then, various barriers need to be overcome in order to facilitate and accelerate BIPV. Besides issues related to mere cost-efficiency ratio, psychological and social factors also play an evident role. The goal of energy change linked to greater use of renewables can be successfully achieved only when all aspects are taken into account and when visual appeal and energy efficiency thus no longer appear to be an oxymoro

Three cases of identity (re)construction through art interventions: the dialogical and the 'sensible'

Identity construction (IC) cannot be reduced to discourses, nor to individual responsibility. Alvesson & Wilmott (2002) suggest two main processes of identity construction : identity regulation (IR, the discursive practices of identity definition) and identity work (IW, the interpretive activities involved in reproduction of self-identity). Based on this dialogic conception of IC, we wonder whether artistic interventions could play a significant role in the IC process, especially through its ability to address the relational, sensible, emotional, and affective dimensions. In other words, our paper intends to better understand the role of experience and the embodiment of sensemaking in the dialogic process of identity construction. In this perspective, we will focus on cases where art interventions take place in working situations at some crucial moments of IC. Exploring the dimension of the sensible encapsulated in artworks and art interventions allows in particular to better grasp how collective understanding of organizations and their transformations hinge on subjectivity (Abrir 2012). This knowledge is generally recognized as disruptive, because of the heterogeneity of the two words of art and organization, the ability of art for ―not-knowing or more generally the ability of art and aesthetics for promoting contradictory emotions. The dimension of the sensible brought by art is characterized by its subjectification power and by its value sharing (the role of emotions and affects, the construction of subjectivity) and value-adding. Our argument is that art, by organizing the co-creation of work-related sensible forms, triggers and performs - in ways we strive at investigating - a collective and dialogic process between IR and IW

Building Integrated Photovoltaics (BIPV): Review, Potentials, Barriers and Myths

To date, none of the predictions that have been made about the emerging BIPV industry have really hit the target. The anticipated boom has so far stalled and despite developing and promoting a number of excellent systems and products, many producers around the world have been forced to quit on purely economic grounds. The authors believe that after this painful cleansing of the market, a massive counter trend will follow, enlivened and carried forward by more advanced PV technologies and ever- stricter climate policies designed to achieve energy neutrality in a cost-effective way. As a result, the need for BIPV products for use in construction will undergo first a gradual and then a massive increase. The planning of buildings with multifunctional, integrated roof and façade elements capable of fulfilling the technical and legal demands will become an essential, accepted part of the architectonic mainstream and will also contribute to an aesthetic valorisation. Until then, various barriers need to be overcome in order to facilitate and accelerate BIPV. Besides issues related to mere cost-efficiency ratio, psychological and social factors also play an evident role. The goal of energy change linked to greater use of renewables can be successfully achieved only when all aspects are taken into account and when visual appeal and energy efficiency thus no longer appear to be an oxymoron

L’incontournable absente. Sur la communication dans les manuels de méthode

L’enseignement des méthodes en sciences humaines se traduit éditorialement par un nombre croissant de publications de type « manuels ». Pour qui s’intéresse à l’épistémologie des sciences humaines, ces manuels représentent une véritable scène d’exposition, de cristallisation, et de modélisation des pratiques de recherche. Il s’agit ici d’analyser comment les « discours de la méthode » intègrent et manipulent, à des degrés et selon des modalités diverses, les dimensions communicationnelles inhérentes à toute recherche. Alors qu’on assiste à un mouvement de prise en compte croissant de l’épaisseur de l’interaction communicationnelle entre le chercheur et les autres acteurs sociaux, le discours méthodologique, de par sa vocation, se trouve pris dans une position contradictoire : s’ouvrir à la complexité des enjeux communicationnels de la recherche (caractère ouvert des situations d’interaction, attitudes de relation aux objets, formes matérielles des documents, rhétorique d’exposition, etc.) tout en réaffirmant les principes d’une épistémologie classique qui assimile la scientificité des procédures à l’extériorité du chercheur vis-à-vis de ce qu’il étudie. Ainsi, de moins en moins « incontournable », la communication demeure-t-elle un objet à conjurer plus qu’à intégrer.Teaching the methods used in the social sciences tends to generate an increasing number of publications of the textbook type. For those who are interested in the epistemology of the social sciences, these books offer an arena in which research practices are exhibited, crystallized, and modeled. The aim of this paper is to analyze how discourses on methodology assimilate the communication aspects inherent in any research, at many levels, and according to various modalities. While there is a trend toward taking increasing account of the depth of communicative interactions between researchers and other social players, by its very nature, methodology finds itself in a contradictory position. That is, it must become aware of the communication challenges presented by research (including the open nature of interactive situations, relationships with objects, the material forms of documents, and expository rhetoric) and at the same time reassert the principles of a classical epistemology that compares the scientific character of practices to the exteriority of researchers toward what they study. Thus, although communication is becoming less and less inescapable, it remains an object that must be averted rather than assimilated

Fast and non-destructive detection on the EVA gel content in photovoltaic modules by optical reflection

Poly(ethylene-co-vinyl acetate) (EVA) has been the dominating material in the photovoltaic (PV) encapsulant market for decades, owing to its superior cost-performance balance. To achieve its desired material properties, EVA undergoes a curing reaction during the module encapsulation process. The resulting EVA gel content after encapsulation is an important criterion for the module encapsulation quality control. Normally, the determination of gel content is achieved using a tedious solvent extraction method. In this paper, a fast and nondestructive detection method on the EVA gel content based on the optical reflection is explored. First, the homogeneity of the EVA gel content distribution after the standard EVA encapsulation process is studied. Then, the feasibility of the proposed optical approach applied to transparent modules is investigated. After that, a method is developed to apply it to opaque modules by incorporating a mirror into the module construction. It was found that the haze factor of the reflected light correlates well with the EVA gel content in the opaque modules. This proof-of-concept work could lead to the development of a fast and nondestructive tool for detecting the EVA gel content in both transparent and opaque PV modules, which is promising for integration as an inline diagnostic tool in the module manufacturing line

The effect of cooling press on the encapsulation properties of crystalline photovoltaic modules: residual stress and adhesion

A high-quality encapsulation process is crucial to ensuring the performance and long-term reliability of photovoltaic (PV) modules. In crystalline Si technology-based modules, poly (ethylene-co-vinyl acetate) (EVA) is the most widely used PV encapsulant. Its encapsulation process is usually performed in a flat-bed vacuum bag laminator. In certain types of laminators, cooling press can be applied to the module cooling process after the module encapsulation, leading to a much higher cooling rate (similar to 100 degrees C/min) than conventional natural cooling due to the application of water cooling circulation and mechanical pressure on the modules. In this work, the effect of the cooling press on the encapsulation properties of PV modules with EVA as the encapsulant are assessed on the aspects of residual stress in the modules, peeling strength between glass and EVA, and the resulting EVA gel content after encapsulation. The results show that the cooling press influences the encapsulation properties of PV modules. In particular by applying the cooling press after encapsulation, the residual normal stress in the Si solar cell in the encapsulated module after cooling can be reduced by as much as 22 +/- 2 to 27 +/- 3% depending on the EVA gel content, whereas the peeling strength between front glass and EVA is increased by similar to 10%. This work should help the further optimization of PV module encapsulation processes aimed at improving module encapsulation quality. Copyright (C) 2013 John Wiley & Sons, Ltd

Compressive-shear adhesion characterization of polyvinyl-butyral and ethylene-vinyl acetate at different curing times before and after exposure to damp-heat conditions

Photovoltaic (PV) module efficiency and reliability are two factors that have an important impact on the final cost of the PV electricity production. It is widely accepted that a good adhesion between the encapsulant and the different substrates of a PV module is needed to ensure long-term reliability. Several testing procedures exist that use a metric derived from the force at interface failure to characterize the adhesion. It has, however, not been demonstrated that those metrics relate directly to the interfacial adhesion (defined as the surface energy density needed to break interfacial bonds), and the obtained results usually relate to an apparent adhesion strength. In this work, we describe a new design for compressive-shear testing of polymer layers bonded to rigid substrates. We use it to characterize real interfacial adhesion of ethylene-vinyl acetate (EVA) and polyvinyl-butyral (PVB) to a glass substrate before and after degradation in damp-heat. Our results show that a peak-force based metric is unable to capture the evolution of adhesion through degradation, and a new metric based on the elastic strain energy of the encapsulant is proposed. Moreover, we show that PVB adhesion to glass is much more affected by damp-heat exposure where polymer saturation takes place, in comparison with the adhesion of EVA to glass. The presented characterization protocol is a powerful tool that can help in assessing the reliability of an encapsulant facing specific degradation conditions. Copyright © 2012 John Wiley & Sons, Ltd