## 4 Conclusions  
This paper analyzed the influence of the improvement in users' thermal expectation levels by using adaptive setpoint temperatures. The analysis was based on the category for new buildings included in EN 16798-1:2019 and was conducted in an international context by analyzing the main cities of four countries of southern Europe and in three different climate scenarios. The results based on 4116 simulations showed the following aspects:  
* The use of adaptive thermal comfort models with a tolerance of 0.00 \({}^{\circ}\)C led to significant energy consumption savings with respect to a highly effective static model. The improvement in users' expectation level implied that, from the narrowing of the comfort zone in 3 \({}^{\circ}\)C (i.e., applying the model with a tolerance of 1.50 \({}^{\circ}\)C), there were no savings in the energy consumption with respect to the static model. However, this tendency was different according to the type of consumption analyzed, demonstrating that the cooling energy consumption had a greater possibility of tolerance. This aspect would imply that, in certain moments, users do not need to set the internal spaces with the linear correlations from EN 16798-1:2019 when the running mean outdoor temperature is near or greater than 30 \({}^{\circ}\)C.
* The application of strategies of adaptive setpoint temperatures for new buildings obtained energy savings greater than 1000 kWh/year in most cities analyzed. Furthermore, there were similar energy-saving tendencies among the countries which were near each other. In this regard, the energy saving was similar between Greece and Italy, and between Spain and Portugal. Spain was the country which was characterized by presenting the greatest and the lowest energy-saving values due to the huge variety of existing climate typologies in the countries, some of which were characterized by a minimum energy demand with the static model.
* The progressive improvement in users' thermal expectations in 0.25 \({}^{\circ}\)C implied a rise with respect to the energy consumption obtained in the previous tolerance level between 6.57 and 9.31% in all the scenarios analyzed.
* In future climate change scenarios, the rise in external temperatures meant that the saving in cooling degrees with respect to the static model increased, thus implying that the maximum tolerance, from which an energy saving was obtained with respect to the static model, increased from 1.50 \({}^{\circ}\)C of the current scenario to 1.75 \({}^{\circ}\)C of future scenarios. This aspect is useful to corroborate the possibilities of using a less demanding upper limit when average external temperatures are near or higher than 30 \({}^{\circ}\)C.  
To conclude, the results of this research give greater knowledge about the possibilities of using adaptive setpoint temperatures and the possible impact the improvement in users' thermal expectations. The research results may provide an opportunity for architects or engineers to establish operational patterns of the most efficient HVAC systems. Furthermore, local governments can design user awareness campaigns to recommend a more appropriate use of HVAC systems by family units. Due to the possible influence of users, further steps of this research will be focused on performing actual monitoring of users using adaptive setpoint temperatures. In addition, the analysis of the combination of adaptive setpoint temperatures and natural ventilation would imply an adaptive strategy framework for mixed-mode buildings. Finally, the case studies from other continents or regions (e.g., United States of America or China) should be analyzed in future works.  
Conceptualization, methodology, investigation, writing--original draft preparation, and editing and visualization, D.B.-H., D.S.-G., C.R.-B. and J.A.P.-A. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
The authors declare no conflict of interest.