1,720,979 research outputs found
Energy performance of PVC-Coated polyester fabric as novel material for the building envelope: Model validation and a refurbishment case study
Tensile materials are concurrently becoming more and more utilized in contemporary architecture design, despite a lack of experimental testing and numerical model development to assess their actual effect on the building behavior, even more, if considered integrated in a second-skin system. In this research, the PVC-coated polyester fabric has been selected and tested as tensile second-skin material by using two outdoor comparative test cells to evaluate its performance and to calibrate and validate a numerical model in TRNSYS 18. Then, the validated numerical model has been used in a case study as a second layer in a flexible façade system. In particular, a simulation refurbishment of a typical three-story office building, located in southern Italy, has been investigated with the aim to evaluate its potential benefits from an energy point of view. The results showed that the refurbishment by means of a second-skin system always allows for an energy saving, up to a maximum of 6.1%; also, by exploiting the semi-transparency and the flexibility offered by this material to implement a continuous whole-façade design on the south wall, thus covering with the second-skin both the walls and the openings, the solar gains across the year can be modulated, by minimizing the gains during the summer and maximizing them during the winter, consequently leading to a reduction of the cooling and heating energy demands, for an overall heating energy demand reduction of about 9.8%
Immersive virtual reality as a tool for lighting design: Applications and opportunities
Immersive virtual reality offers a wide range of applications. Immersive virtual reality in particular can play an important role in lighting design, thanks to its ability to allow a quick assessment between different design choices based on spaces, colours and light. However, immersive virtual reality has to guarantee a correct reproduction of light behaviour from photometric and visual points of view, in order to be effectively used for lighting analysis. This paper presents a literature review aimed to analyse the activities of the research groups operating in this field that have addressed, with different approaches and points of view, the issue of iVR applications in the reproduction of environments illuminated by either daylight or electric lighting, as well as a combination of them
Effectiveness of low-cost non-invasive solutions for daylight and electric lighting integration to improve energy efficiency in historical buildings
This article concerns a field study about the use of non-invasive manual lighting and shading control to save energy in listed buildings. The system was chosen to limit cabling and masonry work. The test room consists of an individual office located in a historical building in Southern Italy. The room was retrofitted with two roller shades (semi-transparent and blackout) and six LED-based pendants provided with step-dimming and three Correlated Colour Temperature options. Shading and lighting could be remotely controlled from the desk by six subjects who took part in the test for two weeks each. Behavioural interventions and a set back to default setting at the end of the working day were adopted to improve the test subjects’ energy behaviour. The results show that energy for lighting could be reduced between 15% and 71% compared to European benchmark, with wide range accounting for variability of individual preference and weather conditions. The savings are due to the computer-based work, the communication and engagement campaign, as well as the default settings. The findings suggest that simple manually controlled systems are energy and economic viable solution for listed buildings, since the system accommodates users’ needs, and proper training is provided to the users
Impact of seasonal thermal energy storage design on the dynamic performance of a solar heating system serving a small-scale Italian district composed of residential and school buildings
A centralized solar hybrid heating system serving a small-scale district composed of 6 typical Italian residential buildings and 3 schools located in Naples (southern Italy) has been modelled, simulated and analysed by means of the dynamic software TRNSYS over a 5-year period. The plant is based on the operation of solar thermal collectors connected to a seasonal double U-pipe vertical Borehole Thermal Energy Storage (BTES) in order to address the seasonal misalignment between solar energy supply and thermal energy demand for heating purposes. In this paper a parametric analysis has been performed in order to investigate the performance of the district heating network upon varying the characteristics of the BTES in terms of: (i) thermal conductivity of soil, (ii) thermal conductivity of grout, (iii) U-pipe spacing, (iv) heat carrier fluid, (v) number of Borehole Heat Exchangers (BHEs), as well as (vi) type of BHEs connection (series, parallel or mixed). The primary energy consumption, the equivalent carbon dioxide emissions and the operating costs of the proposed district heating plant have been evaluated based on the simulation results upon varying the plant configurations and then compared with those associated to a conventional Italian decentralized heating system assumed as reference with the main aims of (i) assessing the potential reduction of primary energy consumption, global CO2 equivalent emissions and operating costs, (ii) exploring the influence of BTES characteristics on the overall system performance as well as (iii) establishing some simple rules for the initial design of BTES
Energy performances assessment of extruded and 3d printed polymers integrated into building envelopes for a south Italian case study
Plastic materials are increasingly becoming used in the building envelope, despite a lack of investigation on their effects. In this work, an extruded Acrylonitrile-Butadiene-Styrene panel has been tested as a second-skin layer in a ventilated facade system using a full-scale facility. The experimental results show that it is possible to achieve performances very similar to conventional materials. A numerical model has then been developed and used to investigate the performances of plastic and composite polymer panels as second-skin layers. The experimental data has been used to verify the behavior of the numerical model, from a thermal point of view, showing good reliability, with a root mean square error lower than 0.40◦C. This model has then been applied in different refurbishment cases upon varying: The polymer and the manufacturing technology (extruded or 3D-printed panels). Eight refurbishment case studies have been carried out on a typical office building located in Napoli (Italy), by means of a dynamic simulation software. The simulation results show that the proposed actions allow the reduction of the thermal and cooling energy demand (up to 6.9% and 3.1%, respectively), as well as the non-renewable primary energy consumption (up to 2.6%), in comparison to the reference case study
Flexible and Lightweight Solutions for Energy Improvement in Construction: A Literature Review
Low-cost smart solutions for daylight and electric lighting integration in historical buildings
Research have shown that the correct integration of daylight and electric lighting reduces the energy use in buildings, while improving visual comfort. Smart shading systems, especially those electrically controlled, play an important role to control solar radiation. Similarly, smart and dimmable/tunable lighting can help to adjust the artificial light to the real users' needs. This paper presents preliminary results of an ongoing living lab study investigating how artificial lighting systems can be integrated with shading systems, placing human comfort at the heart of the study and yet saving energy. A manually controlled, commercial and low-cost smart system integrating two motorized shading devices and six dimmable LED luminaires with a different selection of CCT were installed in a private office in a historical building. Indoor and outdoor lighting conditions and energy consumption associated to the lighting system are constantly monitored to assess how the people use shading and lighting upon varying the boundary conditions.. Preliminary results highlight that users prefer to maximise daylight on the work plane as well as they generally use both shading and electric lighting systems in response to boundary conditions that cause serious discomfort
Thermal model validation of an electric-driven smart window through experimental data and evaluation of the impact on a case study
This study discusses a full-scale Electric-Driven smart window from both an experimental and numerical point of
view. The first part of this paper reports the experimental performances of the investigated smart window, using
a full-scale outdoor test-room. The tests are carried out during the summer under real sky conditions varying the
state of the Electric-Driven window (clear and milky). In the second part, a numerical model is developed and
validated using the data acquired during the in-situ experiments. Finally, the developed simulation model is used
to assess the performances of the Electric-Driven window varying the switching control strategies (from clear to
milky and vice versa) in a refurbishment case study of a building office façade located in the south of Italy. In
particular, the reduction of the indoor air temperature (up to 2.1 °C), the reduction of cooling energy demand (up
to about 41.0%), the primary energy saving (up to about 4.0%) and the reduction of carbon dioxide equivalent
emissions (up to about 2.2%) are evaluated. The analysis is performed comparing the simulation results associated
to a case with the Electric-Driven window with those where a typical double glass low-e window is used
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