Experimental and numerical studies to assess the energy performance of naturally ventilated PV façade systems

This paper presents a holistic approach to assess the energy performance of a naturally ventilated PV façade system. A rigorous combined experimental and numerical approach is established. The real energy performance of the system has been evaluated through a long-term high resolution monitoring of a typical ventilated PV façade system. A numerical model based on TRaNsient SYstem Simulation (TRNSYS) package was developed to assess the thermal and energy performance of the system, which has been verified by a series of statistical analysis using the data collected from the experiment. The validated model was then used to assess the energy and thermal performance of a 7.4 kWp prototype ventilated PV façade system in Izmir, Turkey. The results of this study demonstrated that ventilation in the air cavity of the PV façade system could significantly improve energy performance of the system even in a southeast facing façades. The quantitative analysis provides useful guidance to the system designers for the improvement of energy efficiency of the PV facade system

Silicon PV module customization using laser technology for new BIPV applications

It is well known that lasers have helped to increase efficiency and to reduce production costs in the photovoltaic (PV) sector in the last two decades, appearing in most cases as the ideal tool to solve some of the critical bottlenecks of production both in thin film (TF) and crystalline silicon (c-Si) technologies. The accumulated experience in these fields has brought as a consequence the possibility of using laser technology to produce new Building Integrated Photovoltaics (BIPV) products with a high degree of customization. However, to produce efficiently these personalized products it is necessary the development of optimized laser processes able to transform standard products in customized items oriented to the BIPV market. In particular, the production of semitransparencies and/or freeform geometries in TF a-Si modules and standard c-Si modules is an application of great interest in this market. In this work we present results of customization of both TF a-Si modules and standard monocrystalline (m-Si) and policrystalline silicon (pc-Si) modules using laser ablation and laser cutting processes. A discussion about the laser processes parameterization to guarantee the functionality of the device is included. Finally some examples of final devices are presented with a full discussion of the process approach used in their fabrication

PERFORMANCE OF A LARGE SIZE PHOTOVOLTAIC MODULE FOR FACADE INTEGRATION

International audienceBuilding integration of solar photovoltaic components is a relevant approach for contributing to energy decarbonisation of building applications and so, to reach European climate goals. Thus, in this paper, a large size solar component is studied experimentally and numerically to validate its suitability as building construction element, from the thermal, energy and mechanical points of view. Moreover, a simple linear model of its monthly electrical performance and temperature is developed. After its integration in landscape position using a metal structure on the southern insulated concrete wall of a real building, the solar system was instrumented and monitored during more than one year. Its thermal behaviour and electrical production, and the visible mechanical deformation of the mounting structure were assessed. Monthly photovoltaic performance ratios between 0.5 and 0.7, and efficiencies between 5.9% and 8.3%, were obtained during tests. The module maximum temperature was between 46.5 °C in November 2018 and 63.0 °C in September 2019. No visual degradation was noted. Then, numerical studies of the system in three sites, using the linear model, highlighted most relevant installation configurations, like a south -orientation at Nice. As further study, the system performance reliability will be evaluated after at least three years of operation

Thermoeconomic analysis and evaluation of a Building-Integrated Photovoltaic (BIPV) system based on actual operational data

In this chapter, we considered a building-integrated photovoltaic (BIPV) system, which was installed at Yasar University in Izmir, Turkey, within the framework of an EU/FP7-funded project and has been successfully operated since February 8, 2016. The BIPV system consists of 48 crystalline silicon (c-Si) modules in 4 rows and 12 columns, and the total capacity is 7.44 kWp. We applied the specific exergy costing (SPECO) method to the BIPV system for the first time to the best of the authors’ knowledge. In this regard, we briefly introduced the BIPV system in this study first. We then used the SPECO method for assessing the performance of the BIPV system. Exergetic costs associated with the generated electricity varied between 0.21 and 0.36 €/kWhex for the selected days, with an average exergetic cost of 0.368 €/kWhex for the whole year

Composite material incorporating protective coatings for photovoltaic cell encapsulation

Photovoltaic modules consisting of one back-contact cell were manufactured by vacuum resin infusion process using glass reinforced epoxy composite as encapsulant where the cells are embedded. Incorporation of three coatings onto the composite surface was studied with the aim to improve the electrical performance stability of the modules under ultraviolet (UV), thermal cycling and damp-heat environmental weathering. Photovoltaic and aging performance were examined through the short-circuit current density values and colour change of the composite. Decrease in the initial photovoltaic performance of the modules was caused by the coating deposition. The highest drop in the initial values was observed for the varnish type coating, showing a decrease of 2.6% in short-circuit current. Regarding the performance stability, the decrease was more pronounced in the damp-heat test, presenting the varnish type coating the minimum loss of 1.4% in short-circuit current and a variation of 87% in b* chromatic parameter after 1000 h exposure at 85 °C and 85% relative humidity. The study concluded that the protective coating should be selected to provide the composite modules with an optimal trade-off between the initial electrical performance and the desired stability, with further research work targeted to improve moisture barrier properties.This work was supported by Eurostars Programme (Grant Agreement E12409) and Basque Government Elkartek 2021 Programme (Grant Agreement KK-2021/00066)