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Rising global temperatures have increased the need for research into human adaptability and comfort in buildings. To reduce comfort-related energy demands, low-energy-consumption alternatives for space cooling, such as personal environmental control systems (PECS), are being investigated. The implementation of PECS in office buildings is still underway, and little is known about how occupants' expectations can influence their satisfaction with PECS and indoor environmental quality. This study examines the influence of tailored information and occupants' comfort expectations on their thermal perceptions and satisfaction with a personal ceiling fan. Seventy-six participants completed an online questionnaire and attended a half-day session at 30 °C in a climate chamber in Germany. A manipulation technique to activate personal norms was used to test the influence of information on expectations. Results indicated higher reported thermal comfort in participants with more positive thermal expectations, regardless of their expectations of the building systems. These effects were largely moderated by personal norms, indicating the importance of activating normative motivations to increase thermal comfort. Occupants with negative expectations improved their perceptions of the fan when making personal adjustments to stay comfortable. However, this effect was not moderated by personal norms. Practical implications focus on manipulating occupants' comfort expectations, e.g., by providing occupants with normative messages and individual control, to achieve greater comfort and acceptance of personal building controls in naturally ventilated buildings. [ABSTRACT FROM AUTHOR]

An expected increase in the use of air conditioning by 2050 will significantly increase electricity demand and come at a cost to the environment. Implementing passive cooling strategies and focusing on personal environmental control systems (PECSs) could help to address this issue. While numerous studies have investigated the positive impact of PECSs on thermal comfort and energy savings, their overall economic benefit has been poorly addressed. We present an economic evaluation of personal fans for an office building in Germany. Building performance simulation was used to compare passive and active cooling concepts, and sensitivity analysis was performed for different climate scenarios. A cost-benefit analysis was carried out, including an assessment of investment and operating costs and the monetary value of relative performance. The transferability of comfort and productivity into costs is the novelty of this paper. The results showed that by supplementing night ventilation with personal fans, discomfort hours could be reduced by up to 50%. However, the initial investment of the fan is not compensated by savings in productivity losses compared to night ventilation alone. A reduction in the cost of the technology could help to economically offset the investment. The results contribute to the literature on the economic evaluation of a PECS by proposing a framework to motivate its implementation in buildings. [ABSTRACT FROM AUTHOR]

Research related to personal comfort systems is growing due to their potential to increase an individual's satisfaction with indoor environmental conditions and energy efficiency. At moderately high indoor temperatures, the use of ceiling fans can be a low-energy cooling strategy to enhance comfort in a working environment. This paper studies the performance of a personal ceiling fan and its influence on occupants' satisfaction with the indoor environment, focusing on the effects of personal control, previous experience with fans, variations on participants' activity level and air coming from different directions. In a laboratory study, 41 participants from two age groups were exposed to six different ceiling fan configurations either in sitting or standing positions, with and without control over the ceiling fan speed, and under two thermal conditions (balanced order of in total 24 conditions). Results showed that participants' thermal comfort at indoor temperatures of 28 °C and 31 °C was fulfilled when they used the personal ceiling fan, independent of the direction of the supplied air coming from above. The possibility to control the fan speed showed a significant influence on the thermal perception of participants at a slightly higher activity level compared to fully sedentary. The influence of previous experiences with fans had a positive effect on the rating of the analyzed ceiling fan and thermal comfort. The positive acceptance of personal ceiling fans encourages its use in retrofitted office buildings to increase thermal comfort and motivate energy savings. [ABSTRACT FROM AUTHOR]