Formation analysis of cooling load from envelopes under air-conditioning intermittent operation

• Air-conditioning intermittent operation is considered. • Formation analysis of cooling load is discussed from envelopes. • Interior envelopes contribute to 75 % of total cooling load. • The interior envelopes had the high energy-saving potential. Air-conditioning intermittent operation is commonly employed in office buildings due to occupancy regulations. However, existing research on intermittent operation has mainly focused on individual walls or rooms, with limited investigation into cooling load formation from a whole-building perspective, which is crucial for enhancing energy efficiency in both interior and exterior envelopes. Therefore, this study constructed three representative office buildings and conducted numerical simulation to analyze the formation of cooling load within these buildings. The results demonstrated that optimizing the envelope while considering air-conditioning intermittent operation could significantly reduce the cooling load of the building, including the cooling load of the exterior wall, interior wall and floor slab by 25.57 %, 17.92 %–30.81 % and 58.85 %, respectively. The cooling load of the three office buildings studied can be reduced by 31.98 %–35.11 %, with interior walls and floor slabs contributing up to 82.28 %–89.53 %. This study provides valuable insights into future building design and energy-efficient retrofitting of existing buildings and identifies substantial energy-saving potential.