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[en] Polyfluorene materials have demonstrated to be important components in the fabrication of organic solar cell devices, in both: the active and electron transport layers. The oxidative synthesis as well as optical and electrical properties of new polyfluorene copolymers containing 2,2′-(9,9-dioctyl-9H-fluorene-2,7-diyl) bistiophene and 3-alkylthiophene, alkyl = hexyl (PA1) and octyl (PA2) or 3,4-ethylenedioxythiophene (EDOT) (PM) were investigated. Changes in the HOMO–LUMO energy gap promoted for the insertion of EDOT ring were studied in thick film by using cyclic-voltammetry measurements and compared with the optical properties analyzed by UV–Visible spectroscopy. DFT calculations were used to investigate the possible electronic density distribution and conformational parameter for repetition units into the polymeric structure. Finally, these polymer were preliminary evaluated as donor materials into organic solar cells with architecture ITO/PEDOT:PSS/co-polymer:PC71BM/Field’s metal. Photovoltaic devices showed a very acceptable open circuit voltage (Voc) value, up to 0.92 V.
[en] The awareness and preservation of the vernacular heritage and traditional construction techniques and materials is crucial as a key element of cultural identity. However, vernacular architecture located in earthquake prone areas can show a particularly poor seismic performance because of inadequate construction practices resulting from economic restraints and lack of resources. The horizontal diaphragms are one of the key aspects influencing the seismic behavior of buildings because of their major role transmitting the seismic actions to the vertical resisting elements of the structure. This paper presents a numerical parametric study adopted to understand the seismic behavior and resisting mechanisms of vernacular buildings according to the type of horizontal diaphragm considered. Detailed finite element modeling and nonlinear static (pushover) analyses were used to perform the thorough parametric study aimed at the evaluation and quantification of the influence of the type of diaphragm in the seismic behavior of vernacular buildings. The reference models used for this study simulate representative rammed earth and stone masonry vernacular buildings commonly found in the South of Portugal. Therefore, this paper also contributes for a better insight of the structural behavior of vernacular earthen and stone masonry typologies under seismic loading.
[en] After opening speeches, a first set of contributions, herein presented under the form of Power Point presentations, addresses the new deal for solar heat, and more particularly the new French and European regulatory frameworks, and technical and economic innovations in collective and individual housing (energy saving certificates, interest-free loans, innovating techniques of integration of solar heat into buildings, production simulations and returns on experience). The second session reports innovating actions undertaken by local actors in French regions for local production and for the struggle against climate change, outlines the development of good practices in the solar heat sector (in terms of installation follow-up, of guaranteed quality, of exploitation, and of commitment for quality and performance) with also a presentation of the SHIP2FAIR European project for a high-performance industrial solar heat. It finally proposes a discussion on the role of thermal solar energy in a sustainable building.
[en] Highlights: • A novel organic-inorganic hybrid solar energy storage cell was developed. • AQDS' positive equilibrium potential and fast kinetics facilitate photoelectrons injection. • The photoelectrochemical performance is pH dependent. • Improved unassisted photocharging was demonstrated. - Abstract: Greater levels of solar energy storage provide a promising path for sustainable and reliable utilization of the renewable energy source. One of the greatest challenges towards large-scale implementation of this technology is improving storage capacity and efficiency. The conventional solar-storage architecture, where rechargeable batteries and solar cells are externally coupled, typically results in addition of unnecessary efficiency and reliability margins in design, redundancy of resources (i.e. higher cost), and missed opportunities to increase performance through synergistic integration. Here we overcome these challenges by developing an organic-inorganic hybrid photoelectrochemical storage cell (PESC) to capture and store energy at the point of solar energy generation. The PESC was built by integrating a TiO2 photoelectrode and a Quinone-Vanadium redox flow battery (RFB), which gives rise to superior photoelectrochemical reversibility and stability of the PESC. We demonstrated that photoelectron injection from the TiO2 photoelectrode to the catholyte during unbiased photocharging was significantly enhanced by adjusting pH of the supporting electrolyte. The important charge separation at the semiconductor electrolyte interfaces was also analyzed through electrochemical and photoelectrochemical studies.
[en] The contributions of this conference first proposed an overview of the status and perspectives of the solar thermal energy sector with a presentation of the present situation and perspectives for the French market, and an overview of situations and initiatives in neighbouring European countries. A second session addressed the possible new economical and marketing models able to face challenges of solar thermal energy in 2018 with focuses on heat kWh purchase, on supply portage through a global operator contract (design-realisation-exploitation-maintenance contracts or CREM contracts, energy performance contracts or CPE), and on issues related to building renovation (solar-gas synergy) and to new buildings (regulatory evolution, E+C label). The third session proposed examples of local good practices: development of solar thermal networks in Auvergne-Rhone-Alpes with the development of these networks and a support to commissioners, ADEME's support with patrimony-rehabilitation contracts, and the solar policy implemented by the Brest metropole. A technological focus was then proposed. It addressed communications about the SOCOL approach, concentration-based solar technology (technology, applications, realisations), and solar heating (assets in new and renovated buildings). Before a synthesis, two interventions addressed the production of solar electron and calories, and works performed on the increase of the solar coverage rate
[en] Highlights: • Solar radiation evaluation is integrated with the thermal transfer in clothed humans. • Thermal models are developed for clothed humans exposed in indoor solar radiation. • The effect of indoor solar radiation on humans can be predicted in different situations in living. • The green solar energy can be efficiently utilized in the building development. - Abstract: Solar radiation is a valuable green energy, which is important in achieving a successful building design for thermal comfort in indoor environment. This paper considers solar radiation indoors into the transient thermal transfer models of a clothed human body and offers a new numerical method to analyze the dynamic thermal status of a clothed human body under different solar radiation incidences. The evaluation model of solar radiation indoors and a group of coupled thermal models of the clothed human body are developed and integrated. The simulation capacities of these integrated models are validated through a comparison between the predicted results and the experimental data in reference. After that, simulation cases are also conducted to show the influence of solar radiation on the thermal status of individual clothed body segments when the human body is staying indoors in different seasons. This numerical simulation method provides a useful tool to analyze the thermal status of clothed human body under different solar radiation incidences indoors and thus enables the architect to efficiently utilize the green solar energy in building development.
[en] After an introducing contribution which discussed the difficult evolution of the solar thermal energy sector in 2015, contributions addressed development plans for SOCOL (a plan for collective solar thermal and solar heat) which aims at reviving the market and at opening new markets. A next set of contributions discussed how solar thermal energy can be at the service of energy transition. Following sessions addressed issues like innovation at the service of solar thermal energy, energetic display of solar systems and application of the Ecodesign and Labelling directives, and the reduction of carbon footprint and the energy dependence of territories
[en] The solar photovoltaic installing is a new market in which three types of contractors intervene: the 'solar defenders', characterized by their ecological belief; the traditional craftsmen, and the subcontracting installers. It has been noticed that qualification was not an element in which the firms were involved, but it is socially embedded reality. As to the 'solar defenders', the most legitimate to 'testify' (according convention school) in favor of the ecological order of worth of their activity, they remain few. The reason is the lack of social networks able to support them
[en] The research presented in this paper is an example of application of biologically inspired design in the course of development of a solar device for thermal processing with improved capabilities and efficiency. This research demonstrates the complexity of the design process which necessarily includes parallel application of bionics principles and engineering methods and techniques. In the first part of the research a bionic survey was performed in order to recognize solutions in natural systems with the ability to control the intensity of sunlight. In the second part the basic requirements for an improved design of the solar device for thermal processing were established, according to the extracted bionic principles, as well as in line with the conclusions of the review of the advantages and disadvantages of existing solar devices. The adopted principles were applied in the process of concepts generation. The best concept was selected and developed with application of additional engineering methods. (author)