Comprehensive analysis of HVAC control factors for elderly residents in hot and humid regions: A case study in Hong Kong

Abstract

Occupant behavior significantly impacts energy consumption and indoor comfort through HVAC (Heating, Ventilation, and Air Conditioning) system operation. Existing behavioral models in building energy simulations mainly focus on environmental parameters, often overlooking physiological and social factors. This study introduces a multidimensional model that incorporates environmental perception, societal, economic, familial, physiological, and psychological factors. Data from 344 participants aged 60 and above were collected using questionnaires and indoor sensors during hot-weather months in 2021 and 2022. Logistic regression was employed to develop an HVAC usage model integrating physiological and environmental factors, revealing the explanatory power of diverse variables on HVAC operations. The results indicate that age, gender, income, housing size, family relationships, and sleep patterns have the highest explanatory capacity for air conditioner and fan usage. Non-physical factors are as significant as physical environmental factors for fan usage. The air conditioning model is most sensitive to income level. Low to moderate-income elderly individuals use air conditioning for much shorter durations compared to high-income counterparts, and aging reduces activation times, with a more pronounced effect in males. Additionally, hotter weather will amplify the gaps in expected air conditioning usage times due to income, age, and gender differences.