# Thermal Comfort and Sustainability in University Classrooms: A Study in Mediterranean Climate Zones
## 5 Conclusions and Future Research  
Thermal comfort is an essential factor in the design and operation of educational spaces, as it directly affects students' well-being, concentration and academic performance. In Mediterranean regions, where high temperatures during the summer and variable conditions during the rest of the year present particular challenges, it is essential to address thermal comfort in a context that also considers energy efficiency and the impact of climate change. Air-conditioning systems provide thermal stability, but their energy consumption underlines the importance of using more sustainable strategies such as natural ventilation where possible. In this paper, thermal comfort was assessed in university classrooms in southern Portugal with different modes of operation (natural ventilation and air conditioning). Through environmental measurements and subjective student surveys, thermal perceptions and preferences were analysed, as well as the influence of factors such as classroom position and individual characteristics, including differences in the thermal insulation of clothing. The main novelty of this study lies in the detailed exploration of how students' location within the classroom affects their thermal perception as a function of mode of operation, considering proximity to sources of ventilation and air conditioning. In addition, neutral and comfort temperatures were calculated, comparing the results with current regulations and showing significant thermal gradients in the space, which provides valuable information for the air-conditioning improvement strategies and the more comfortable design and efficient educational environments. After carrying out the analyses, the following conclusions can be drawn:  
* In NV classrooms, indoor temperatures were maintained in the range of 25-32 \({}^{\circ}\)C. It was observed that thermal comfort conditions can be achieved if the outside temperature does not exceed 28 \({}^{\circ}\)C, provided that appropriate strategies such as cross-ventilation, good distribution of openings and adequate clothing are designed. However, when the outside temperature reaches higher values, thermal discomfort increases significantly. * In classrooms with AC, indoor temperatures ranged from 22-26 \({}^{\circ}\)C, maintaining mostly \"Neutral\" to \"Slightly cool\" thermal sensations. However, cold areas were identified near air vents and warm areas near windows exposed to the sun, highlighting the importance of a design that minimises the thermal gradient. * Occupants' habits play a crucial role in thermal comfort. Choosing appropriate clothing for the environment and adopting adaptive behaviours (such as adjusting windows or positioning oneself strategically) can mitigate discomfort. * Differences in clothing levels between men and women reflect the importance of considering cultural and social characteristics when assessing thermal comfort. Promoting climate-appropriate clothing habits can improve the well-being of occupants. The results of this work underline the importance of designing classrooms that balance thermal comfort and energy efficiency. In this sense, a mixed approach is proposed that prioritises natural ventilation as the principal solution on days with moderate temperatures, with air conditioning only being used when outside temperatures exceed comfort limits. Future lines of research will include the analysis of hybrid strategies combining NV with passive and active systems, as well as the evaluation of the seasonal impact on thermal comfort. It will also be crucial to develop localised adaptive models for Mediterranean climates, which integrate not only environmental conditions, but also cultural factors, such as clothing habits, and adaptive behaviours of students. These approaches will contribute to designing sustainable educational spaces that optimise occupant well-being and minimise environmental impact. Conceptualisation, P.R., M.T.M. and V.V.-A. ; methodology, P.R., M.T.M. and V.V.-A. ; validation, P.R., M.T.M., R.I., J.I.A. and V.V.-A.