Thermal Comfort and Perceived Air Quality (Paq) Using Automatic Ceiling Fans in Residential Buildings

Abstract

In a warming climate, resilient and low-energy methods for cooling the occupants are needed to ensure energy efficient and adaptive thermal comfort. Air movement, particularly through ceiling fans, is an effective way to provide comfort in warm conditions, potentially minimizing or even avoiding the need for more energy-intensive air conditioning systems. While several studies have provided evidence on the cooling potential of elevated air speed in various climate conditions and office settings, little attention has been paid to the method of air delivery and its automatic control in residential buildings. Considering the need for energy-efficient cooling solutions to achieve plus energy buildings, and the growing expectations for smart systems, this study demonstrates how automatic ceiling fans can effectively reduce cooling needs. This study aims to validate an algorithm for automatically adapting ceiling fan speed based on room thermal conditions, focusing on subjective thermal satisfaction and perceived air quality (PAQ). A comprehensive environmental chamber study was conducted with 30 participants across three different indoor air temperatures conditions (27°C, 29°C and 31°C). Participants provided feedback on thermal satisfaction and IAQ perception for four fan operational modes: Automatic (downward flow), Manual Direct (downward flow), Manual Reverse (upward flow), and Off. The automatic operation achieved comfort levels comparable to manual control, with no statistically significant differences in thermal satisfaction. Direct flow mode (downward) significantly outperformed reverse flow mode in thermal satisfaction, especially at higher temperatures (31°C). Air movement improved perceived air quality in fan On modes compared to fan Off condition across all temperatures. These findings validate the effectiveness of the automatic control algorithm in maintaining thermal satisfaction and highlight the performance of direct flow mode, particularly at higher temperatures. In the face of climate change challenges, this study contributes to the development of resilient and smart personalised control systems for cooling in residential environments.

Keywords: Personalized Environmental Control Systems (PECS), Ceiling Fans, thermal comfort, Perceived Air Quality, Automatic Control, Technologies for Plus Energy Buildings