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

Passive Strategies for Building Retrofitting: Performances Analysis and Incentive Policies for the Iranian Scenario

A large amount of the Iranian energy demand is related to the building sector, mainly due to its obsolescence. In this paper, a second-skin system has been implemented as a retrofit action for an office building, evaluating the effect of a tensile material as second-skin in terms of primary energy saving, carbon dioxide equivalent emissions, and simple payback period. The analysis was carried out through numerical simulations across a whole year and for four Iranian cities (Tabriz, Teheran, Yazd, and Bandar Abbas) in four different climates (cold, temperate, hot-dry, and hot-wet), and with the building aligned at either north-south or east-west. Moreover, an economic analysis was carried out suggesting different incentive policies to promote building energy refurbishment. The simulation results highlighted a favorable orientation for buildings in Iran, suggesting a guideline for new constructions. Indeed, the best results were achieved for an east-west orientation of the building (up to a primary energy saving of 13.6% and reduction of carbon dioxide equivalent emissions of 45.5 MgCO2,eq, in Yazd), with a decrease of the annual specific total (cooling and thermal) energy demand of 37.9 kWh/m2 /year. The simple payback period values were also lower in the east-west orientation than the north-south one

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%

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