Energy Performance Assessment of COVID-19 Building Recommendations in Singapore

Several guidance recommendations on how to operate air-conditioned buildings have been provided to reduce risks of indoor COVID-19 transmission. These include increased outdoor air intake, before and after occupancy indoor air purging and enhanced air cleaning. Using a whole-building energy model to represent a typical large commercial office building in Singapore, we evaluate the energy impact of these recommendations. In univariate analyses, increasing outdoor air percentage beyond 30% is associated with increased energy consumption by 11% and raised prevalence of unmet cooling setpoint to 80%. Utilising MERV14 media filters, upper room UVGI and high clean air delivery rates (CADR) per power portable air cleaners increased modestly the energy use intensity (EUI) up to 6.3%. However, operating UVGI at the AHU and social distancing measures resulted in energy savings. Full factorial simulation resulted in a total of 576 recommendation combination options with 72 that have energy performance index higher than − 10% and prevalence of unmet cooling setpoint lower than 15%. Through multivariate analyses comparing all recommendations, the dominant variables that influence energy consumption and unmet cooling setpoint are social distancing and outdoor air percentage respectively. The most energy efficient combination options involve the recommendation of 30% outdoor air, AHU UVGI and MERV14 filters. The results from this full factorial simulation may provide different combination options for building managers or owners to select from.