2017
Author(s): Schiavon S, Yang B, Donner Y, Chang VW, Nazaroff WW
In a warm and humid climate, increasing the temperature set point offers considerable energy benefits with low first costs. Elevated air movement generated by a personally controlled fan can compensate for the negative effects caused by an increased temperature set point. Fifty-six tropically acclimatized persons in common Singaporean office attire (0.7 clo) were exposed for 90 minutes to each of five conditions: 23, 26, and 29 degrees C and in the latter two cases with and without occupant-controlled air movement. Relative humidity was maintained at 60%. We tested thermal comfort, perceived air quality, sick building syndrome symptoms, and cognitive performance. We found that thermal comfort, perceived air quality, and sick building syndrome symptoms are equal or better at 26 degrees C and 29 degrees C than at the common set point of 23 degrees C if a personally controlled fan is available for use. The best cognitive performance (as indicated by task speed) was obtained at 26 degrees C; at 29 degrees C, the availability of an occupant-controlled fan partially mitigated the negative effect of the elevated temperature. The typical Singaporean indoor air temperature set point of 23 degrees C yielded the lowest cognitive performance. An elevated set point in air-conditioned buildings augmented with personally controlled fans might yield benefits for reduced energy use and improved indoor environmental quality in tropical climates.
DOI: 10.1111/ina.12352
Journal: Indoor Air