The Effect of Seasons and Prevailing Environments on Adaptive Comfort Temperatures in Open Plan Offices

Abstract

Creating comfortable indoor climates is one of fundamental functions of buildings and buildings use a large amount of energy to fulfill their function. Therefore, it is important to understand how and under what thermal environments, the occupants can achieve their comfort in their normal lives. This paper reports the results from a longitudinal field investigation, which has been conducted to reveal the comfort temperatures of occupants in open plan offices in summer, autumn and winter in Seoul, Korea and to identify the environmental factors that could affect comfort temperatures. The survey results confirm that comfort temperature would vary with seasons. This research provides the evidence to link the indoor and outdoor temperatures along with past thermal experience with comfort temperatures. An adaptive comfort model has been developed by this study for building occupants in Seoul, Korea based on the field investigation. Comparisons between the new adaptive comfort model and existing models have been also made. The establishment of an adaptive thermal comfort model for Seoul would have a significant impact on energy saving and for setting of thermal comfort standard for office buildings in Korea.

A review of human thermal comfort in the built environment

“…Authors highlighted the increased air velocity by fans as one of the measures participants used to improve their comfort conditions [232]. Thermal comfort temperatures were also determined for an office building with hybrid ventilation in Seoul, South Korea and a new adaptive comfort model to that climate was proposed [233]. Nicol and Humphreys [234] determined adaptive comfort models (thermal acceptability ranges relating the outdoor running mean temperature and the indoor comfort temperature) for European office buildings operating with natural ventilation or during the heating or cooling operation, based on SCATs database.…”

Development of the adaptive PMV model for improving prediction performances

“…(13) and (14) give the revised form of Adaptive PMV model (aPMV model) for cool and warm conditions, then aPMV model was presented by the following equation:…”

“…Recent field studies show that adaptive comfort models have a large potential in evaluating and predicting actual thermal comfort sensation of people [13][14][15][16][17]. Adaptive thermal comfort models for naturally ventilated buildings are now well developed and included in international standards such as EN 15251 [18] and ASHRAE Standard 55 [3].…”

Cooling Energy Implications of Occupant Factor in Buildings under Climate Change

“…Previous studies [25,26] show that occupant behavior is a critical factor in determining comfort temperatures, and thus occupant behavior has significant energy implications. In Scenario 3, the setpoint temperatures for the VRF system during the cooling season from May 1 to October 31 were determined by the adaptive comfort model of air-conditioned buildings located in South Korea [19]. Scenario 4 addressed practices of occupant use of nighttime free cooling for the ERV.…”

“…For example, the use of windows by building occupants has been shown to be closely related to prevailing indoor and outdoor conditions [16,17]. Field studies on the use of air-conditioning systems by building occupants are relatively rare, but the existing research reveals that occupant control of air-conditioning systems is a key determinant in changes in building energy consumption [18,19]. Thus, it is evident that occupant behavior should be considered in any analysis of the effects of climate change on energy use in buildings.…”