Air conditioning is crucial for maintaining thermal comfort and health for the elderly during cooling seasons, particularly given their reduced adaptability. It is essential to first explore and establish the users’ demand profile to meet the elderly's unique needs, due to their weakened physiological and psychological adaptation abilities. This study aimed to characterize the users’ demand profile of indoor air conditioners for the Chinese elderly during cooling seasons. Fifteen elderly individuals at a care facility in Chongqing were selected. Moreover, 534 air conditioners’ operation datasets were collected from the Internet of Things platform and were clustered by the K-means algorithm. The results showed that the users predominantly turned on and operated air conditioners during midday, post-meal and sleep periods. They preferred setting temperatures between 26.0°C and 28.0°C, automatic wind speed and no-wind direction modes. Minimal adjustments were increasing temperature by 1.0°C –2.0°C, reducing wind speed and reverting to no-wind direction settings. Three usage demand profiles were identified by considering single operation duration and named evening comfort with moderate adjustment demand, dual-peak short-duration stable maintenance demand and sleep comfort long-duration no-wind direction demand. These findings directly inform age-optimized air conditioning technologies, emphasizing adaptive automation, sleep-optimized modes and energy efficiency for future aging-friendly residential and care facilities design.
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