In order to reduce greenhouse gas emissions and achieve global decarbonisation, it is essential to find sustainable and renewable alternatives for electricity production. In this context, the development of distributed generation systems, with the use of thermodynamic and photovoltaic solar energy, wind energy and smart grids, is fundamental. ORC power plants are the most appropriate systems for low-grade thermal energy recovery and power conversion, combining solar energy with electricity production. The application of a micro-scale ORC plant, coupled with Parabolic Trough Collectors as a thermal source, can satisfy domestic user demand in terms of electrical and thermal power. In order to develop a micro-scale ORC plant, a commercial hermetic scroll compressor was tested as an expander with HFC-245fa working fluid. The tests required the construction of an experimental bench with monitoring and control sensors. The aim of this study is the description of the scroll performances to evaluate the application and develop optimization strategies. The maximum isentropic effectiveness is reached for an expansion ratio close to the volumetric expansion ratio of the scroll, and machine isentropic effectiveness presents small variations in a wide range of working conditions. The filling factor is always higher than one, due to leakage in the mechanical seals of the scroll or other inefficiencies. This study demonstrates that using a commercial scroll compressor as an expander within an ORC system represents a valid option for such applications, but it is necessary to improve the mechanical seals of the machine and utilize a dedicated control strategy to obtain the maximum isentropic effectiveness.

Focus on the role of users is the heart of the ongoing research experience in the university Living Lab environment that investigates, systematises and tests the potential of the latest digital technologies in the construction sector (BIM-sensors-Digital Twin-IoT) to define enabling building-user interfaces that support the virtuous circle of energy efficiency/environmental well-being/proactive behaviour. Synchronising the real building/virtual model allows an augmented environmental experience and new levels of user involvement. It enriches the predictive systems of data-user experience, helping to calibrate the configuration of improvement scenarios in the design/operational phase on well-being objectives, expanding the awareness of the process actors for a new centrality of the decision as an ethical value.

This work presents a methodological approach for the assessment of the combined effects of air enthalpy variations due to the presence of green systems and building thermodynamics. It serves as a valuable tool for energy sustainability improvement of urban areas and for defining scenarios of integrated energy strategies with low environmental impact from the perspective of green energy transition and environmental sustainability. The proposed approach is based on two energy environmental methods, i.e., top-down and bottom-up. Using environmental thermodynamics, they allow for the evaluation of energy sustainability of green ecosystem services in urban areas and their areal distribution in different built-up zones. The proposed methodological approach is an effective operational tool for urban energy and environmental sustainability evaluations, focusing not only on the reduction of anthropogenic impacts, mitigation of urban heat islands, and climate change adaptation but also on promoting energy-efficient microclimate changes.

Although the literature is rich in studies of indoor thermal comfort, there is a lack of research on outdoor thermal comfort, despite its importance in response to global warming and the rise of urban heat islands. Physics models addressing spatial (urban energy form, green areas) and temporal (climate variability) factors are urgently needed. This study proposes a useful method for outdoor comfort evaluation at a district scale, based on the energy form of built-up areas and hyperlocal climatic conditions. It enables the determination of distributed Physiological Environmental Temperature values at a district scale, assessing the greenery effect and mutual radiative exchanges. Applied to a case study in Florence, Italy, it integrates multiple measurement techniques. The main results highlight the model’s ability to evaluate outdoor thermal perception through the new identified indicator of Virtual Physiological Environmental Temperature (PET*) spread, ranging from 23.5 to 101.0 °C, specifically referring to the worst climatic conditions inside an urban canyon in relation to different real scenarios. The results confirm the method’s effectiveness as a tool for thermodynamics and planning for the well-being of an urban built-up environment. It offers useful support for sustainability and human-centric design, oriented to UHI mitigation and climate change adaptation strategies.