Thermal Comfort and Energy Efficiency: Challenges, Barriers, and Step towards Sustainability

With the increasing number of people living in cities, the demand for energy in office buildings and homes is constantly increasing; thus, smart buildings were created to provide users with better comfort conditions. However, using artificial systems becomes an unsustainable alternative for these environments. This research conducted a literature review of studies published in Scopus and Web of Science between 1970 and 2022 to identify studies that contained strategies to promote thermal comfort and energy efficiency in buildings, as well as the main challenges and barriers to sustainability. A total of 9195 articles related to the topic were identified, and after applying the defined criteria, 105 were included in this review. Three research questions were investigated, and the main findings of this research are: (i) it is more difficult to assess thermal comfort and thermal sensation than energy efficiency; (ii) to promote a thermally comfortable environment, it is necessary to consider numerous aspects to reduce environmental impacts and energy consumption and to increase sustainability; (iii) actual thermal conditions are influenced by factors such as energy levels, climate, setpoint types, building type, size and orientation, and economic factors, among others; (iv) new technologies found in smart buildings showed distinct performances according to the climates of each region, and their evaluations can cover thermal comfort, energy savings, and payback time.