## 3 Results
### Mid-Season Warm  
Mid-season warm occurs commonly in spring. Cooling is necessary from the end of September. During this season, sunny and partly cloudy days cause a similar time duration of PCM phase change as in the summer season. However, the temperature was not enough to activate the PCM on cloudy days (Figure 10b). Figure 11: Results for representative days of mid-season cold. (**a**) Outdoor temperature and global horizontal radiation (GHI); (**b**) global vertical radiation; (**c**) HVAC power and energy consumption; (**d**) indoor air temperature & mean radiant temperature (MRT); (**e**) heat flux; (**f**) PMV; (**g**) PMV; (**h**) DGP. Figure 12: Results for representative days of winter. (**a**) Outdoor temperature and global horizontal radiation (GHI); (**b**) global vertical radiation; (**c**) HVAC power and energy consumption; (**d**) indoor air temperature & mean radiant Temperature (MRT); (**e**) heat flux; (**f**) PMV; (**g**) PMV\({}^{*}\); (**h**) DGP. Regarding the daily cooling energy consumption during mid-season warm, the PCM room shows less energy consumption than the AIR room (Figure 6). Thus, the cooling energy saving was 18.4%. There is a slight reduction in the energy consumption in the PCM room during partly cloudy and sunny days (Figure 10c) due to lower heat conduction (Figure 10e) and solar heat gains (Figure 10b) through the PCM window. On the other hand, the peak loads in both rooms are similar (Figure 10c). Otherwise, on cloudy days, there is almost no cooling and heating energy consumption in either office because the thermal inertia of the facade can keep the indoor air temperature within the comfort range, even at lower outdoor temperatures. For partly cloudy and sunny days, PCM glazing helps to keep the PMV and PMV* (Figure 10f,g) values close to 0 during the morning because solid PCM can maintain the mean radiant temperature in the comfort range (Figure 10d). Indeed, PCM glazing has the same impact on thermal comfort on partly cloudy and sunny days of mid-season warm, as during summer. On the other hand, there is no difference between the two rooms on cloudy days because PMV is mainly dependent on air temperature (controlled by the HVAC) instead of mean radiant temperature. Moreover, Figure 7 shows a significant reduction in the highest PMV and PMV* values, such as in summer, due to the PCM in solid-state blocks of direct solar radiation for a few hours in the morning. Concerning the impact of PCM glazing on visual comfort, no noticeable difference between the two rooms was observed during partly cloudy and sunny days, similar to the summer season. However, the DGP in the PCM room was slightly higher than that in the AIR room (Figure 10h). The interreflections of the daylight within the PCM in the solid-state cause high luminance, which turns into occupant discomfort due to glare. Figure 10h also shows that the DGP is below 0.25 in both rooms on cloudy days, so there was no glare. Nevertheless, during the first and last hours of the day, the daylight availability decreased in the PCM room, which meant artificial lighting was needed to provide enough indoor illuminance. Consequently, the DGP variation during the whole monitoring period was higher in the PCM room (Figure 8). afternoon allow PCM to solidify, releasing heat into the indoor environment. On the other hand, the PCM phase change does not occur during cloudy days, as shown in Figure 11b. The total heating energy savings in the mid-season cold are 36.2%. The longer time of the phase change reduced the heating demand of the PCM room, which mainly occurred early in the morning and in the evening (Figure 11c). During the afternoon, the PCM usually turns solid and helps to reduce energy consumption, releasing stored heat into the indoor environment. Additionally, Figure 6 shows that the lowest energy consumption takes place in autumn for both rooms.