The Influence of Solar Control Films on Energy and Daylighting Performance by Means of Experimental Data and Preliminary Unsteady Simulations

Abstract Solar control films were investigated as a strategy to improve thermal comfort, lighting conditions, and energy performance in non-residential buildings. The case study follows two adjacent similar offices with large window in the south-west facade of a building in Perugia, investigated by numerical and experimental approaches. The solar control films could strongly reduce the window heat gain (40-60%) and the indoor air temperature (1-1.5 °C), whereas the daily average illuminance level was lowered by about 50-60%. Finally the yearly cooling energy demand decreases of about 25% (only South- West facade) and 39% (all the facades), whereas the heating energy demand increases of about 10-15% thanks to solar control films

Masonry wall panels retrofitted with thermal-insulating GFRP-reinforced jacketing

Today there is a need to provide thermally efficient walls, while at the same time to increase the mechanical properties of old unreinforced masonry walls that will not require large amounts of energy in the retrofitting or deconstruction processes. To address this problem, this paper gives the results of shear tests carried out on masonry panels made of solid bricks retrofitted with a new technique based on the use of glass fiber-reinforced polymers (GFRP) grids inserted into a thermal insulating jacketing. This was made of different low-strength lime-based mortars. Tests were carried out in laboratory and results were used for the determination of the shear modulus and strength of the wall panels before and after the application of the GFRP reinforcement. Retrofitted panels exhibited a significant enhancement in the lateral capacity when compared to the control panels. The thermal performance of the proposed mortars was also investigated both with and without GFRP. Low values of thermal conductivity were found, especially for the samples with GFRP; a reduction of the thermal transmittance value in the 34–45 % range was also obtained by applying 45 mm layer of coating in conventional masonry walls

Thermal and Acoustic Performance Evaluation of New Basalt Fiber Insulation Panels for Buildings

Abstract Thermal insulation of building envelope is very important in energy saving: a growing interest is focused on using insulating recycled and sustainable materials. The thermal and acoustic properties of innovative basalt natural fiber insulating panels were investigated. The thermal conductivity was evaluated by means of a Heat Flow meter apparatus: it is included in 0.030-0.034 W/mK range. The acoustic absorption coefficient was measured by means of Kundt's Tube. The results were compared to traditional solutions with similar chemical composition, but worse mechanical resistance. The easy application of this solution could be useful especially for refurbishments

Development of Innovative Aerogel Based Plasters: Preliminary Thermal and Acoustic Performance Evaluation

The thermal and acoustic properties of innovative insulating systems used as building coatings were investigated: Granular silica aerogel was mixed with natural plaster in different percentages. This coating solution is transpiring and insulating, thanks to the use of a natural lime coat and aerogel, a highly porous light material with very low thermal conductivity. The thermal conductivity of the proposed solution was evaluated by means of a Heat Flow meter apparatus (EN ISO 12667), considering different percentages of aerogel. The natural plaster without aerogel has a thermal conductivity of about 0.50 W/m

Experimental and Numerical Energy Assessment of a Monolithic Aerogel Glazing Unit for Building Applications

In the last few decades, the attention of researchers has been focused on the characterization of aerogels in order to improve the thermal performance of transparent building envelopes. Granular aerogel is already spread in the market thanks to the easy manufacturing system, whereas the difficulty in producing monoliths without defects, cracks, and inhomogeneity limited the diffusion of monolithic aerogel systems. A new production process for the monolithic panels was developed at Union College (Schenectady, NY, USA); it is a rapid supercritical extraction technique which allows a reduction in production time (only a few hours) and results in less solvent waste. Panes with maximum dimensions of about 100 × 100 mm were fabricated and composed in a unique glazing system, with external dimensions 300 × 300 mm. The thermal characterization of the innovative monolithic aerogel glazing system (simple float glazing 4.7-mm-thick monolithic aerogel pane 15-mm-thick simple float glazing 4.7 mm thick), which was carried out by means of a Small Hot Box apparatus, showed a thermal transmittance value of about 1.1 W/(m2K). Data was used in dynamic simulations of a typical non-residential building. They showed that the new investigated solution allows a valuable reduction with respect to a low-e double glazing system in terms of heating energy demand (about 5–7% for Helsinki, 8–12% for Paris, and 10–15% for Turin), for different window-to-wall ratios

Prediction Of Indoor Conditions And Thermal Comfort Using CFD Simulations: A Case Study Based On Experimental Data

Abstract In the present paper CFD tool was used for thermal comfort evaluation in natural convection and in transient conditions in a room by setting only the external weather conditions as input parameters. A survey in a classroom at the Department of Engineering, University of Perugia, was carried out and data required for the thermal comfort evaluation and CFD simulation model set up was acquired. The simulation model was validated with experimental data and it was used for the thermal and velocity profiles simulation and for the thermal comfort indexes calculation, according to UNI 7730

Thermal Behaviour and Energy Saving Evaluation of Innovative Reinforced Coatings

Abstract The use of fibre-reinforced interlayer structures as coatings is very spread in building refurbishment, but it is important to find effective solutions both for mechanical and thermal performance. In the present paper the thermal behaviour of innovative fiber-reinforced coatings was investigated in order to find the best solutions in terms of mechanical strength and energy saving in buildings. Four different coatings (with and without the internal reinforced structure) were considered and their thermal conductivities were preliminary investigated by using an innovative measurement apparatus (Small Hot Box). A thermal analysis was carried out for the evaluation of the effects of the coatings on the building envelope, especially the thermal transmittance, calculated for different thickness. Preliminary results showed that 3-4 cm of coatings allowed to reduce thermal transmittance of building envelope by about 60-70%. In order to evaluate the energy saving, one building was considered and simulated by means of Trnsys software: it was chosen for the evaluation of the refurbishment of the building by using the selected solutions. The simulation model was implemented in SketchUp and the energy demand with and without the innovative coatings was simulated; the simulation model was also used for the evaluation of energy saving in different climate conditions. Results show that for two coatings an important reduction of the heat loss through of the building envelope can be obtained

Thermal and Acoustic Properties of Aerogels: Preliminary Investigation of the Influence of Granule Size

8th International Conference on Sustainability in Energy and Buildings, SEB 2016 The influence of granules size in silica aerogels is experimentally investigated in terms of thermal and acoustic performance characteristics. The transmission loss (TL) is measured at normal incidence in a traditional impedance tube, whereas the thermal conductivity (?) is evaluated using a Hot Plate apparatus, setting up an appropriate methodology, due to the nature of the sample. The results reveal that the small granules (granules size in the 0.01-1.2 mm range), which have the highest density, have the best performance both in terms of thermal and acoustic properties. Depending on the granules size, ? varies in 19-22 mW/mK range at 10°C, whereas a TL equal to 13 dB at about 6400 Hz for 20 mm thickness is obtained for small granules. © 2017 The Authors

Energy and Environmental Performance Analysis of Biomass-fuelled Combined Cooling and Heating System for Commercial Building Retrofit: An Italian Case Study

Abstract This study focuses on the operating performance of a biomass boiler (100 kW) coupled with an absorption chiller machine at the service of a commercial building in central Italy. A detailed life cycle environmental assessment (LCA) was performed by comparing the biomass-fuelled system to conventional system, using the SimaPro software. To assess the environmental impact, experimental data, such as energy consumptions and emission factors of the biomass boiler, were used as input data. Biomass-fuelled system was found to have the lowest impact in cumulative energy demand (CED), global warming potential (GWP), and ReCiPe single score method