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• TT PS-TIM smart window provides dynamic regulation of solar admission. • Impacts of design factors of TT PS-TIM window on building performance are presented. • Evaluated an office performance with TT PS-TIM window using an inclusive approach. • Applying TT PS-TIM window results in energy saving of up to 27.1%. • The TT PS-TIM window offers significant improvement in daylight performance. With the increasing awareness of building energy efficiency, indoor environment quality for human wellbeing and working efficiency, efforts have intensified in to inventing intelligent building components. This paper provides a first step in developing a novel multi-effect smart window system, which achieves enhanced energy efficiency and an improved indoor luminous environment by integrating a Transparent Insulation Material (TIM) structure incorporating a Thermotropic material. This system automatically regulates the admittance of solar heat and natural light into the building by responding to a changing environment while taking advantage of the increased thermal resistance and scattered daylight of window integrated TIM. A comprehensive workflow via EnergyPlus and RADIANCE was used to accurately predict the luminous and energy performance of applying the smart window system on a typical south-facing office under selected climates (London, Stockholm, Rome and Singapore). The effect of the optical properties and transition temperature of thermotropic material on building performance was explored in detail. Annual simulation results predict that, with a careful selection of the Thermotropic material properties, installing the TT PS-TIM window system is able to yield up to a 27.1% energy saving when compared with a conventional double glazed window, under the modelled Rome climate. TT PS-TIM windows also provide dynamic daylight control, resulting in increased daylight availability with the percentage of working hours that fall into the UDI 500–2000 lx range increasing to 62.3%. The results of this research provide guidance for the next step of the material design and development that seek to balance energy efficiency and solar and daylight control through the use of thermotropic materials. [ABSTRACT FROM AUTHOR]

• Development of Hybrid Renewable Energy System model for off-grid RBS applications. • Definition of a multi-objective optimization methodology for design. • Study of the effects of local weather conditions on system performance. • Lowest LCOE achieved in the order of 0.48 €/kWh with low CO 2 emissions. • Highest LCOE for the worst-case scenario of about 0.66 €/kWh. The previous works on the use of PEM Fuel Cell based power supply system for the operation of off-grid RBS (Radio Base Stations) sites showed a strong influence of system design parameters on the energy conversion performance. In this paper a perturbation of system design is studied with validated models to understand the variability of performance over a full year operation. Moreover, a multi-objective optimal sizing methodology is proposed in terms of the minimization of a functional parameter taking into account costs, RES (Renewable Energy Sources) exploitation and pollutant emission factors. The influence of different weather conditions on the HRES (Hybrid Renewable Energy Systems) performance is analyzed investigating the system behavior for three different locations in Europe. The analysis of three real case studies showed that 20% ratio of the energy produced by fossil fuels over the energy produced by renewables sources can be obtained slightly increasing the PV (PhotoVoltaic) plant size with minor effects on the RES exploitation. Moreover, a lower LCOE (Levelized Cost Of Energy) can be achieved increasing the PV size and reducing battery size with an unavoidable reduction of the RES exploitation. Results for different sites highlighted the obtainment of different optimal sizings for each site. However, similar performance parameters can be obtained in the different case studies for Tilos, Rome and Brighton with an average LCOE of 0.5 €/kWh and a variability in the order of 0.1 €/kWh. [ABSTRACT FROM AUTHOR]

• Identification of solution sets to reduce construction costs in nearly zero energy houses. • 15% maximum reduction of energy related construction cost in Continental Italy. • 26% maximum reduction of energy related construction cost in Mediterranean Italy. • Net present values up to 163 €/m2 after 50 years building lifetime. Concerning Nearly Zero Energy Buildings, it is important to guarantee energy efficiency, thermal comfort and indoor environmental quality, while keeping construction and operational costs low. In this framework, this paper explores the efficacy of applying different scenarios, for reducing construction costs of new nearly zero energy multi-family houses in a life cycle perspective. Conversely to the standard cost-optimal approach, a real Italian case study building was chosen. Alternative and unconventional combinations of solutions for envelope and technical systems were adopted. Calculations were performed in two Italian cities (Rome and Turin). Three types of analysis were developed thermal comfort, energy performance and financial calculation. Results of the thermal analysis show that the installation of active cooling to prevent summer overheating can be avoided by applying low-cost passive strategies. All the proposed low-cost scenarios (4 alternative scenarios in Rome and 5 in Turin) reached the highest grade of energy performance, with a reduction of the non-renewable primary energy consumption up to 46% compared to the base case in Rome and 18% in Turin. From the economic perspective, all the scenarios in the two climate zones allow both reductions in the construction costs, up to 26% in Rome and 15% in Turin, and a Net Present Value after 50 years up to 163 €/m2 in Rome and 158 €/m2 in Turin. [ABSTRACT FROM AUTHOR]