A refined theoretical method for reducing overestimation in building-level design cooling load derived from temporal misalignment of room-level design cooling loads

The design cooling load is a decisive factor in air-conditioning system design, with significant impacts on equipment sizing, energy use, and carbon emission. However, directly summing room-level design cooling loads (r-DCLs) generally produces an overestimated building-level design cooling load (b-DCL) due to the temporal misalignment. In this study, a refined theoretical method was proposed based on a process of temporal decomposition and reconstruction. Specifically, the r-DCL (calculated using the heat balance method) and temporal characteristics (extracted via Fourier-based frequency-domain analysis) are used to generate 24-hour hourly cooling load profiles for each room. These profiles are then temporally aggregated to obtain the building-level hourly cooling load profile. Finally, the maximum value of the aggregated profile is selected as the b-DCL. The results show that the MAE ranges from 3.10 W/m 2 to 11.27 W/m 2 . The MAPE varies between 1.67% and 4.21%, while the MedAE falls within 2.60 W/m 2 to 7.81 W/m 2 . Future work would focus on the development of an accurate r-DCL calculation method in the absence of sufficient meteorological data and the exploration of more robust statistical approaches for selecting DWD.