The building sector is known to have a significant environmental impact, considering that it is the largest contributor to global greenhouse gas emissions of around 36% and is also responsible for about 40% of global energy consumption. Of this, about 50% takes place during the building operational phase, while around 10–20% is consumed in materials manufacturing, transport and building construction, maintenance, and demolition. Increasing the necessity of reducing the environmental impact of buildings has led to enhancing not only the thermal performances of building materials, but also the environmental sustainability of their production chains and waste prevention. As a consequence, novel thermo-insulating building materials or products have been developed by using both locally produced natural and waste/recycled materials that are able to provide good thermal performances while also having a lower environmental impact. In this context, the aim of this work is to provide a detailed analysis for the thermal characterization of recycled materials for building insulation. To this end, the thermal behavior of different materials representing industrial residual or wastes collected or recycled using Sardinian zero-km locally available raw materials was investigated, namely: (1) plasters with recycled materials; (2) plasters with natural fibers; and (3) building insulation materials with natural fibers. Results indicate that the investigated materials were able to improve not only the energy performances but also the environmental comfort in both new and in existing buildings. In particular, plasters and mortars with recycled materials and with natural fibers showed, respectively, values of thermal conductivity (at 20 °C) lower than 0.475 and 0.272 W/(m⋅K), while that of building materials with natural fibers was always lower than 0.162 W/(m⋅K) with lower values for compounds with recycled materials (0.107 W/(m⋅K)). Further developments are underway to analyze the mechanical properties of these materials.

An estimation of a stand-alone solar PV and wind hybrid system for distributed power generation has been made based on the resources available at Sagar island, a remote area distant to grid operation. Optimization and sensitivity analysis has been made to evaluate the feasibility and size of the power generation unit. A comparison of the different modes of hybrid system has been studied. It has been estimated that Solar PV-Wind-DG hybrid system provides lesser per unit electricity cost. Capital investment is observed to be lesser when the system run with Wind-DG compared to Solar PV-DG.

Our research aims to achieve dual-positive effects in the presented study by raising photovoltaic (PV) panels over the water surface. With this, target experiments were primarily conducted to evaluate the efficiency increments of the PV panel while reducing its operating temperature through passive convective cooling obtained by raising it over water. The following objective was to estimate the reduction in water evaporation due to the shading effect induced by the panel placed inside the same basin. The performance of two PV panels was analyzed, one used for tests, the other as a reference. The characteristic curves were determined under the local environmental conditions of Cagliari, Italy. The true temperature reduction and efficiency gain calculations of panel P1 due to water cooling was achieved via the measured temperatures and calculated efficiencies of panel P2 at environmental conditions. The water height inside the basin was constantly monitored and maintained at approximately 7.5 cm below panel P1, which covered about 17% of the total water surface area. The presence of water underneath P1 leads to its efficiency increment on average by 2.7% (absolute) and about 17.22% (relative). At the same time, temperature of panel P1 dropped by 2.7 °C on average. The comparative water evaporation study conducted with and without P1 inside the basin showed a 30% reduction in water evaporation.

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Old masonry buildings represent the largest part of traditional constructions. Generally, they are both seismically vulnerable and thermally dispersive. Therefore, the need for seismic and thermal retrofitting aimed at reducing their vulnerability and environmental impact has motivated research efforts towards sustainable retrofitting solutions. This study presents a literature review of the approaches currently available for masonry retrofitting. Specifically, it highlights the use of fiber in textile form i.e., Textile Reinforcement Mortar (TRM), as Fiber Reinforced Polymer (FRP) and natural fibers (animal and plant sources) to masonry retrofitting. In addition, specific attention is devoted to the integrated (structural and thermal) fiber-based integrated retrofitting techniques that are becoming very important in the last years.

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This paper presents with an effective and fast approach to the optimization of the pretension forces in arched bridges with suspended deck, which makes use of the influence matrix method (IMM). The given cable-tensioning procedure leads to a linear system of equations with a reduced number of unknowns and can be effectively implemented within active control procedures that handle time-varying loading conditions. This method produces a target bending moment distribution (TBMD) over the structure, which significantly mitigates the state of stress of the deck. Numerical simulations referred to a Nielsen arch bridge illustrate the versatility of the proposed approach when dealing with different loading conditions.

For ages, natural fibers have been used as building materials. In the last centuries the man-made fibers, steel and concrete have predominantly dominated construction sector. Climate change has highlighted the importance of sustainable construction that can reduce the carbon footprint and the application of green, natural, recyclable and sustainable. In this work, the chemical composition and the effectiveness of jute fibers used as reinforcement in thermal and structural mortars. Therefore, the physical properties of both jute fiber and composite were determined by Scanning Electronic Microscope (SEM), which show a good compact microstructure in case of structural mortar and bonding inhomogeneity in case of thermal mortar. The fibers improved ductility of the mortars, yet reducing their flexural and compressive strengths.