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38th European Photovoltaic Solar Energy Conference and Exhibition; 1535-1537, The Be-Smart project aims to contribute significantly to the strengthening of the European industrial sector in the field of solar energy and to present and demonstrate new concepts of low- cost photovoltaic (PV) products for building integration (BIPV) with a high quality architectural design (transparency, color…) named Energy positive Glasses or EpoGs. For a relevant choice of these products installation configuration, an experimental study of the impact of various parameters (see IEC TS 63126 standard) on the temperature of photovoltaic glass-glass monocrystalline silicon mini-modules is being performed for nearly one year on five different sites. A comparative analysis of first results obtained at the CEA INES site and the CEA Cadarache site is presented focusing on their maximum and their 98th percentile temperatures from December 2020 to May 2021. This most representative temperature should be considered to define EpoGs installation configuration per site. For facade integration, in cold period, the glass layers thickness seems to have an influence on photovoltaic modules temperature. As further studies, data measured in warm period will be analyzed. Then, in order to consider edges effect, similar tests will be performed on large PV modules integrated to a facade at the CEA INES site.

38th European Photovoltaic Solar Energy Conference and Exhibition; 1532-1534, A photovoltaic installation is subject to many constraints (such as weather conditions, shocks or dust) that can result in its ageing (such as delamination, discoloration or mould) and thus to performance losses. Only few measured data are available for an accurate long-term prediction of the performance of photovoltaic modules connected in series or building integrated. Some methods permitting to evaluate the impact of each kind of degradation on a photovoltaic field electrical production were proposed and compared. They were applied to a rooftop BIPV system based on its performance ratio and its degradation rate. A performance diagnosis of this installation was also proposed. Compared to the state of art which indicates a degradation rate between 0.5 and 0.8%/year for a rack mounted photovoltaic module, the BIPV system studied had a degradation rate of nearly 4%/year. The majority of the defects detected seems to be related to electrical issue, in particular at the level of the interconnection between the photovoltaic cells and of the bypass diodes in the electrical system. As further steps, a subprogram permitting to determine the evolution over time of the production of a BIPV system will be developed considering different types of installation and photovoltaic technologies.

37th European Photovoltaic Solar Energy Conference and Exhibition; 1937-1940, Building integration has a huge impact on photovoltaic modules operating conditions and, then, on their performance compared to rack-mounted systems, according to their locations on roof or façade. Thus, existing detailed and simplified prediction models are suitable for some kind of solar installations but are less accurate for other configurations. In this study, based on an experimental database obtained with the various test benches mounted during the last ten years at CEA INES site, a detailed analysis of performance indicators was realized in order to define simplified equations to predict BIPV modules thermal behaviour and electrical performance according to their integration configuration and technology. Relative errors of up to 0.07 % for the performance ratio equations and 0.30 % for the electrical energy production equations were obtained. Finally, a comparison of each BIPV system according to their locations on building envelope was performed in order to highlight their advantages and limitations. Thus, annual performance ratio values varied between 81 % and 89 % for inclined roof installations and 41% to 66% for façades systems. As further study, more equations would be selected in order to optimize the accuracy of the systems prediction at the thermal and electrical levels.

37th European Photovoltaic Solar Energy Conference and Exhibition; 1951-1955, Integration of photovoltaic components on building envelope is an essential solution to obtain Nearly Zero Energy Building. In order to permanently optimize electrical and thermal performances of photovoltaic facade, the facade functionalities should adapt and evolve with climatic and weather conditions. Bio-inspired design is a breakthrough approach to provide adaptability to physical, mechanical and optical properties of photovoltaic envelope. Therefore, this paper presents numerical parametric studies of a photovoltaic ventilated facade realized with the purpose to identify the properties that should acquire adaptive feature. In addition, physics related to the identified parameters allow paving the way for the search and the selection of suitable biological adaptive mechanisms. The results of this study indicate that radiative and optical properties of the photovoltaic ventilated facade are the most influential and conflict-inducing parameters on both its electrical and thermal performances. Thus, to provide adaptability to those properties, biological search should be led on live species dealing with extreme heat and radiation and developing adaptive functions aiming to control solar radiation intake.

36th European Photovoltaic Solar Energy Conference and Exhibition; 1746-1748, PVSITES project has developed an ambitious set of BIPV solutions specially tailored to provide a comprehensive and robust answer to market demands. One of these solutions is a low concentration PV solution with associated passive climate control properties for building integration in façades and skylights. Glass-glass semitransparent PV modules in conjunction with integrated optical elements are proposed to concentrate solar radiation onto the cells during the central part of the year and allow light passing towards the interior of the building during the winter. At the central part of the year, the lenses deviate solar radiation onto the cells with a double effect: (1) an increase in PV production in comparison with a traditional PV system of same installed power and (2) a reduction in cooling demands due to an enhanced solar control, with less radiation entering the building during the summer. The savings provided by the system are obviously greatly enhanced in locations with high direct irradiation conditions. The system is being demonstrated in three experimental outdoor set-ups with different climates: two experimental test benches in ACCIONA facilities (Seville, Spain), Field Lab Testing facility at Tecnalia site (Derio, Spain) and FACT building at CEA-INES (Chambéry, France).

In the framework of increasingly demanding legislation related to energy performance in buildings, the integration of photovoltaic systems in the building skin offers many possibilities. However, a continuous development of the building-integrated photovoltaics (BIPV) market in the next years necessarily demands the compliance with strict requirements in terms of design flexibility, aesthetics, durability, cost reduction, grid integration, testing standards and operation & maintenance. Within this context, a European consortium of 15 partners is developing the H2020 PVSITES project, “BIPV technologies and systems for large-scale market deployment”. The project will demonstrate an ambitious set of BIPV solutions, specially tailored to provide a comprehensive and robust answer to market demands. This paper focuses on some of the major results achieved at the time of writing. These include a detailed BIPV market and regulatory framework analysis and recommendations for the standardization of BIPV products. Novel developments of glazed crystalline silicon modules for BIPV integration are presented, with both opaque and see-thru variations. Also included are the selection of a battery technology best suited for inclusion in a custom-made building energy management system (BEMS), as well as a BIM-compatible software tool to assist the design of BIPV projects.

32nd European Photovoltaic Solar Energy Conference and Exhibition; 2746-2749, The thermal analysis of a building integrated photovoltaic/thermal prototype (BIPV/T) suitable for fodder drying is presented. This component consists in photovoltaic modules inserted in a metal absorber. Similar test models were installed at INES site at Le Bourget du Lac and at CSTB site at Sophia Antipolis and compared. The experimental setup in both sites was composed of two test benches differentiated by the insulation of the backside of one of the absorbers. A PV field was used as reference. The insulation of the test bench leads to the heating of PV modules of nearly 10°C in days considered. The overall thermal conductance of each test bench was determined using a linear equation representing the impact of solar radiation on the heating of PV modules. This parameter decreases with the level of PV modules cooling. Also, this linear equation could be used for a first prediction of PV modules temperature in various building integration configurations. As further studies, the BIPV/T component will be analyzed on longer periods on the two sites. Then, the prototype will be integrated into a 35m² test bench of fodder drying installation at INES site in order to optimize its design (air flow rate, ducts size…).

31st European Photovoltaic Solar Energy Conference and Exhibition; 2696-2698, This article presents the numerical and experimental analysis of the performance of two rooftop building integrated solar PV/T hybrid air collectors (BIPV/T) and a BIPV façade. Some main problematic of this kind of component is that energy needs and their production are not always concomitant. Moreover, their configurations don’t always permit to obtain optimal operative conditions for both thermal and electrical production. Thus, the objective of this work is to propose area for improvement of their performance based on three applications. The first system was designed to be coupled with a ventilation system. The second system comprising a metal absorber was designed for fodder drying. The advantage of this application is that it is realized during summertime, when PV modules most need to be cooled. The third application was a bifacial BIPV double-skin façade. For each system, the thermal and electrical numerical models developed are presented as well as their validation on various test benches and a demonstrator. Numerical and experimental parametric studies permitted to define first area of improvement of solar components performance. Thus, some influencing parameters were defined: the thickness of air gap, the air velocity and the optical properties (emissivity) of layers, especially PV modules front glass.

The SOPHIA project has developed a Strategic Research Infrastructure Agenda for photovoltaics in Europe, with an analysis of existing RIs, current trends in their access and use as well as recommendations for future, upgrading.. It is hoped that these will be addressed by public and private funding. Where appropriate these should be taken up by ESFRI (European Strategy Forum on Research Infrastructure) in the next update of its roadmap), with a view to set up a whole range of multi-purpose RI, addressing the whole PV value chain form the lab to the fab all along the TRL scale. It should further enable flexible cooperation and optimal use by European user communities. The work on the SRIA document has led to the following provisional recommendations, which will be refined after stakeholder feedback for publication in January 2015, JRC.F.7-Renewables and Energy Efficiency

28th European Photovoltaic Solar Energy Conference and Exhibition; 3986-3988, This work presents a feedback of the experimental and numerical analyses of an innovative solar PV/T hybrid air collector integrated into a fodder drying installation of 770 m² mounted on a roof of a farm at Puygros in Savoy. At the moment, only 220m² of PV field include an insulated air gap of 330mm thick at the underside. The preheated air extracted is blown using two extractors into drying areas through ducts. The PV field of 70.61kWp is connected to seven inverters. Thermal, electrical and aerodynamic measurements are performed. The first experimental and numerical estimations of the thermal and electrical performances of the solar system according to some parameters permitted to highlight areas for improvement of this installation. Thus, many observations have been made. Wind seems to have a predominant effect on the air velocities at the inlets of the air gap, even in drying periods. With the partial installation of the air gap, natural ventilation seems to be sufficient for the cooling of PV modules. Moreover, the daily thermal production is greater than the electrical production. As further studies, technical solutions will be sought in order to optimize the heat extraction and the PV modules cooling.

27th European Photovoltaic Solar Energy Conference and Exhibition; 3916-3921, The global Building Integrated Photovoltaic (BIPV) market was estimated at 1.2 GW in 2010 and is expected to increase at more than 50% compound annual growth rate to reach a capacity of 11 GW in 2015. In particular in France the feed-in tariffs greatly favour such BIPV systems, with an increasing variety of integration structures. One of the specificities of such systems is their potential increased temperature due to lower ventilation, associated loss of performances and possible long-term degradation effects. This temperature increase can be difficult to quantify, therefore altering the reliability in the rate of return of an installation. The purpose of this work is to study experimentally the thermal behaviour of photovoltaic systems integrated into building rooftops (BIPV technology) to calibrate advanced thermo-electric model (subject to a second communication) to determine guide lines of good practice for simulations of BIPV systems. This analysis also permits the identification of effective methods to characterize and compare different technologies and installation practices, in terms of energy losses or energy incertitude.

27th European Photovoltaic Solar Energy Conference and Exhibition; 4143-4149, The advantage of BIPV systems is to obtain multifunctional building envelope by adding functions such as weather impact protection in addition to electro-technical properties. Based on the results of the BIPV task of SOPHIA research program, the main purpose of this work is to analyze the thermal related electrical behaviour of BIPV systems according to environmental conditions. Various steady state and dynamic numerical models have been realized by the partners. CEA INES developed in TRNSYS software a 2D steady-state model of PV modules integrated into roof. AIT uses different approaches of modeling: a stochastic volumetric path tracing of spectral light, infrared and visible absorption and emission of surfaces, local average of illumination respecting local climate, surrounding buildings. Fraunhofer ISE realized a steady-state temperature model for BIPV systems, including the dependence on the cell operation mode. In order to evaluate all relevant aspects in BIPV applications, a real-time power balance model has been developed at Fraunhofer IWES in holistic approach. In order to evaluate the accuracy and the relevance of numerical models, they present an overview and an analysis of the existing optical, thermal and electrical models.

26th European Photovoltaic Solar Energy Conference and Exhibition; 3808-3811, This work concerns a solar PV/T hybrid air collector which can be integrated into a building roof. It is composed of photovoltaic modules that can be ventilated or not on the underside through an insulated air gap. Firstly, a steady state 2D model of the component following a nodal approach is presented. The pressure gradient of temperature within the layers is supposed to exist only in the direction of drainage of the stream of air. The temperature at each node can be considered as a mean temperature. The air gap is discretized through the collector length. Then, the prototype is studied under a full building integration setup in order to determine its influence on the building energy demands. The addition of 4 m² of this solar collector in a building double flow ventilation system enables to reduce the heat demands by nearly 1%. As further step, this numerical study will be carried out on a test bench in situ.

25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 5150-5152, This work deals with an integrated solar PV/T hybrid air collector suitable for applications such as heating and drying of hay and industrial products. The main purpose of this study is to evaluate and optimize the thermal and electrical performances of this PV component and its integration system. A 2D mathematical model describing the thermal behaviour of the component is presented. The simulation values are compared to the measured data obtained under steady conditions on a solar PV/T air collector. Then, a description is provided regarding the in situ experimental studies which are carried out on three various models of the same component, in order to validate the thermal model previously developed. As further steps, various simulations will be performed on a drying system under a full building integration setup.

25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 4116-4118, This study concerns a solar PV/T hybrid air collector which can be integrated into a building roof. It is composed of photovoltaic modules that can be ventilated or not on the underside through an insulated air gap. Firstly, a steady state 2D model of the component following a nodal approach is presented. Secondly, the experimental study carried out under controlled radiation conditions on a test bench mounted in the laboratory under a solar simulator is described. An experimental comparison is performed between the calculated and the measured data. Finally, an experimental parametric study is realized in order to determine the influence of factors such as the thickness of the air gap on the thermal performance of the system. In a further step, the prototype will be studied under a full building integration setup.

33rd European Photovoltaic Solar Energy Conference and Exhibition; 2882-2887, In the framework of increasingly demanding legislation related to energy performance in buildings, the integration of photovoltaic systems in the building skin offers many possibilities. However, a continuous development of the building-integrated photovoltaics (BIPV) market in the next years necessarily demands the compliance with strict requirements in terms of design flexibility, aesthetics, durability, cost reduction, grid integration, testing standards and operation & maintenance. Within this context, a European consortium of 15 partners is developing the H2020 PVSITES project, “BIPV technologies and systems for large-scale market deployment”. The project will demonstrate an ambitious set of BIPV solutions, specially tailored to provide a comprehensive and robust answer to market demands. This paper focuses on some of the major results achieved at the time of writing. These include a detailed BIPV market and regulatory framework analysis and recommendations for the standardization of BIPV products. Novel developments of glazed crystalline silicon modules for BIPV integration are presented, with both opaque and see-thru variations. Also included are the selection of a battery technology best suited for inclusion in a custom-made building energy management system (BEMS), as well as a BIM-compatible software tool to assist the design of BIPV projects.