Forces

Abstract

Humans spend 90% of their lives inside buildings, but often the Heating, Ventilation, and Air Conditioning (HVAC) systems of commercial buildings do not properly maintain occupant comfort. Use of feedback through comfort voting applications has been shown to improve the quality of service, but the effects of application feedback and user interface design has not been investigated. In this work, we present several methods of feedback that use data presentation and environmental interaction in comfort voting applications. Through a 40 week user study of 61 University employees across 3 buildings, we show that feedback systems can be used to increase user satisfaction with thermal conditions from 33.9% to 93.3% and reduce energy consumption up to 18.99% compared to a system without voting. In addition, we find that by including a drifting control strategy, we find energy savings up to 37% can be realized without a significant reduction in satisfaction.

Upscaling participatory thermal sensing: Lessons from an interdisciplinary case study at University of California for improving campus efficiency and comfort

“…The general strategy is to solicit thermal comfort "votes" (e.g., hot, cold) from building occupants and integrate that data into the HVAC management system. Most prior studies of PTS focused on university buildings ( [3][4][5][6][7][8][9][10]23,11,16,24,14,12]), although a company called Comfy has commercialized PTS and produced reports and publications on their system (e.g., [13]).…”

“…However, PTS programs at universities have often been based on simulations, not actual occupant behavior. A few field experiments are the exception ( [3,4,5,16,12]), but these were relatively limited in terms of the testbed, participation, and/or duration of the experiment.…”

“…Lam et al [16] deployed their system in three testbeds: a classroom with 87 students for 3 h; a room in an office building with 13 occupants for 10 days; and a conference room with 12 people for the duration of 4 meetings. Winkler et al [12] tested their control system across 3 buildings with 61 people for 40 weeks. The relatively small and controlled testbed in these studies was reasonable given the difficult task of developing an automated closed-loop PTS system.…”

Occupants’ Interaction With an Occupant Voting System for Thermal and Indoor Air Quality Feedback – Case Studies in Office Spaces

“…The authors concluded that the OVS was not suitable for benchmarking but appropriate for collecting occupants' complaints on the thermal environment. Winkler et al (2016) explored different implementations and designs of a smartphone app to collect thermal sensation votes. The votes were used as an input to the thermal comfort model developed by Fanger (ANSI/ASHRAE, 2013) which was used to determine the preferred indoor temperature for controlling heating, ventilation and air-conditioning (HVAC).…”

“…First, very few studies were identified (e.g., Lassen et al, 2020) that evaluated the reliability of occupant votes (Lee and Karava, 2020;Sheikh Khan et al, 2020). Second, most studies used smartphone apps (e.g., Winkler et al, 2016) without considering other alternatives of user interfaces (Lee and Karava, 2020;Sheikh Khan et al, 2020) and how that might affect the collected occupant votes. Finally, researchers in some studies actively encouraged and reminded occupants to frequently vote (e.g., Jazizadeh et al, 2014;Lee and Karava, 2020;Sheikh Khan et al, 2020).…”