I. Farrou, M. Kolokotroni, M. Santamouris
Bibliographic info:
Proceedings of the 34th AIVC - 3rd TightVent - 2nd Cool Roofs' - 1st venticool Conference , 25-26 September, Athens 2013

Future climate change might have a tremendous impact on energy use, ventilative cooling strategies and thermal comfort in buildings, since these parameters are strongly correlated with the external weather conditions.
This paper will present results of a study of the impact future climate change scenarios as developed by the Intergovermental Panel on Climate Change (IPPC) and implemented in weather files for specific future time slices (2020, 2050 and 2080) on the design of the external envelope of a hotel building in Greece. Three climatic regions of Greece are considered.
The impact of climate change on the building is assessed via hourly simulations using a calibrated model developed using the software TRNSYS. The model was calibrated using measured energy use data from an existing hotel building. Future climate weather files were constructed for the three climatic regions using METEONORM data and the ‘morphing’ method using a weather generator software (Weather Generator v1).. The heating and cooling loads (kWh/m2/yr) of the building are calculated using monitored climatic data for the years 1970-2010 and future climatic files for the years 2020, 2050 and 2080. Two modes of buildings are studied: a. all year operated, and b. seasonally operated. The effectiveness of the most energy efficient techniques is investigated for the three climatic zones of Greece via a parametric study. The climate change mitigation strategies examined are described by the principles: ‘blow away’ (intelligently controlled night and day ventilation), ‘switch off’; (shading), ‘reflect’ (cool materials) ‘reflect and switch off’ (glazing), ‘switch off & absorb’ (insulation) and ‘convection’ (ceiling fans). For each principle, a parametric analysis was carried out to define the ‘optimum’ buildings in each climatic period.
Results indicate an increase of the cooling load by 15% in year 2020, 34% in year 2050 and 63% in year 2080. On the other hand heating load is expected to decrease by 14% in year 2020, 29% in year 2050 and 46% in year 2080.
It was found that different strategies can be applied to all year and seasonally operated buildings for the most energy efficient performance. These include:
a. For all year operated buildings: high levels of insulation, double low e glazing, intelligently controlled night and day ventilation, ceiling fans and shading. The building of year 2050 would need more shading and the building of year 2080 would need additional shading and cool materials.
b.For seasonally operated buildings: Intelligently controlled night and day ventilation, cool materials, ceiling fans, shading and double low e glazing. Only the building of year 2080 would need insulation.