PSI - Issue 55

Francesca Frasca et al. / Procedia Structural Integrity 55 (2024) 32–38 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 3. Energy demand for heating (red bars) and cooling (blue bars) in Trondheim (left panel) and Rome (right panel) during the RP period in an un-retrofitted case and two retrofitted cases with thermal insulation of the same building.

Fig. 4 shows that in FF period the total ED of buildings in Trondheim keeps higher than that in Rome, even though the gap tends to be smaller. In Trondheim, the total ED will tend to significantly decrease (around 66%) but with the occurrence of a very small extent of cooling ED (less than 1 kWh·m -3 ·year -1 , not visible in Fig. 4). In Rome, the expected increase of the outdoor temperatures will be responsible for tripling the cooling ED (blue bars) that will be in turn compensated by a significant decrease in the heating ED (red bars). However, the final effect on the total ED is a slight increase of only 8% with respect to RP.

Fig. 4. Energy demand for heating (red bars) and cooling (blue bars) in Trondheim (left panel) and Rome (right panel) during the FF period under SSP5-8.5 scenario in an un-retrofitted case and two retrofitted cases with thermal insulation of the same building.

It is worth noting that the ED is here calculated taking into account only the conduction heat transfer through the opaque building components. It means that the effect of solar gains and ventilation is completely neglected. It follows that although low thermal transmittance values allow to reduce the energy demand (retrofit 1 and retrofit 2), overheating issues can be encountered in high solar gains and poor ventilation conditions, thus leading to an increase of cooling ED. In addition, such conditions can further be exacerbated by urban heat island and urban canyoning effects which are typical in urban contexts (Lopez-Cabeza et al., 2022) like the densely populated Rome (Battista et

al., 2023; Salata et al., 2022). 4. Discussion and Conclusions

This study has investigated the potential changes in heating and cooling energy demands in museums under the extreme Shared Socio-economic Pathways climate scenarios SSP5-8.5 (corresponding to the highest greenhouse gases emissions with a radiative forcing reaching 8.5 W∙m -2 by 2100). For the first time, degree-days were computed, taking