Thermal Comfort and behaviour: The combination of ... · Thermal comfort - that condition of mind that expresses satisfaction with the thermal environment and is assessed by subjective

Thermal Comfort and behaviour: The combination of psychological incentives and personalised conditioning systems

Ziqiao LiSupervisors:

Prof. Dennis LovedayDr. Peter Demian

Doctoral Seminars

TermsThermal comfort - that condition of mind that expresses satisfaction with the thermal

environment and is assessed by subjective evaluation

Thermal sensation - a conscious feeling commonly graded using the categories cold,cool, slightly cool, neutral, slightly warm, warm, and hot;it requires subjective evaluation

Thermal evaluation - subjective evaluations include thermal comfort, sensation,acceptability and preference

Thermal comfort envelope - acceptable thermal environment from various combinationof environmental parameters

Injunctive norms - the circumstances that people would be expected to behave in acertain way, otherwise they would be judged as disapproval

Descriptive norms - the way that majority people behaved

Background

A Story about TomHi

Open-plan office;Central HVAC system;Operable windows

BackgroundA Story about Tom

ASHRAE 7-points scale

Sometimes:Tom felt warm and uncomfortable

Sometimes:Tom felt slightly warm but comfortable

Sometimes:Tom felt neutral and comfortable

Sometimes:Tom felt warm and uncomfortable but acceptable

BackgroundA Story about TomYou may want to ask…?

Hey Tom, when you felt uncomfortable, why didn’t you adjust thermostat?

Office workers have less motivation (Karjalainen, 2007)

Slow response speed (Dantsiou, 2015)

Conflict with other colleagues (Dantsiou, 2015)

Personalised conditioning systems (PCS)

Personal comfort system; Personalised ventilation system;Task ambient systems……

Providing individually cooling and heating;Satisfying own preference;Quick and perceivable response;

Background

Figure 1 Personalised Conditioning systems

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40

New thermal comfort zone with Personalised systems

Arens (1998) Zhai (2013) Arens (1998) Zhang (2010) Zhai (2013) (1.2 METs) (1.0 METs)(Floor fans) (Desk fans)

Figure 2 Comfort envelope affected by PCS

head/face/upper body local air jets overhead fans

side large-area air flows (including

window ventilation)conditioned chairs

footwarmers, legwarmers,

kneehole radiant panels

Corrective power (CP) (-1K ~ -4K) cooling (-0.5K ~ -7.5K)

cooling(-2K cooling/ 10K

heating)(-4K cooling/ 9K

heating) (2.2K~ 6K)

Table 1 Corrective power for various PCS (Zhang, 2015)

BackgroundA Story about TomYou may also want to ask…?

Hey Tom, when you felt slightly warm, why did you feel comfortable?

Thermal comfort adaptation

Physiological Adaptation

Behavioural Adaptation

Psychological Adaptation

Figure 3 Deviations of neutral temperatures from Predictions

Psychological incentivesEnergy feedbacksSocial norms

Encourage people to use adaptation options

BackgroundPsychological incentives

Energy feedbacks

Heating Setpoint: 22°C

Hey Tom, during the last one hour,You consumed 10kWh electricity. Hey Tom, during the last one hour,Your consumption is equivalent to 20 pages of A4 paper.

Heating Setpoint: 20°C

Social normsInjunctive norms and descriptive norms

Heating Setpoint: 22°C

Your energy-using behaviour is disapproval. Please help environment.

Hey Tom, Join your other colleagues to help with protecting environment.

Heating Setpoint: 20°C

People tend to behave like others who have similar features, and are more willing to follow the norms of groups in which they feel they are involved. (Goldstein, 2008)

Its effects have been proved in many aspects: Prevent smoking (Murray, 1984); Stop throwing litter (Keizer, 2011); Recycling and energy-saving behaviours in offices (Schultz, 2016)……

Figure 4 energy-saving potentials of various aspects

For example, adding social normative information in the personal energy report could lead to 6.4% of energy saving in the office. (Handgraaf, 2013)

Research Questions1. To what extent do psychological incentives affect the thermal evaluation of

office occupants?

2. To what extent do psychological incentives potentially affect the heating-use

behaviours of office occupants?

3. How much energy potentially can be saved by applying psychological incentives

in workplaces?

4. What are the most acceptable approaches to deliver psychological incentives

to office workers?

Can Tom be more satisfied and acceptable to the local environment with the help of psychological incentives and personalised conditioning systems?

AimTo investigate whether psychological incentives influence the thermal comfort 'envelope' and behaviour of office workers who have access to localised, personal space-conditioning systems, leading to reduced energy demand.

Objectives(1) Identify the most common types of localised personalised conditioning systemscurrently available;

(2) Review the range of possible psychological incentives that could be adopted inrelation to management of personal thermal sensation and energy use;

(3) Using human subjects, conduct experiments in a controlled environment to compareenergy-use behaviours and thermal evaluations (thermal sensation, comfort, preferenceand acceptability) with and without the influence of psychological incentives forenergy saving;

(4) Conduct a field investigation to confirm the extent to which such incentives can beaccepted by office workers in actual offices in conjunction with personalisedconditioning systems;(5) Evaluate the results, and the impact of the findings, on office energy demand andthermal comfort, and make recommendations for future systems design and policy.

Methodology

Questionnaire-based experiment in Climate chamber

Objective 1 (Personalised conditioning systems) – literature reviewObjective 2 (Psychological incentives) – literature reviewObjective 3 (Psychological incentives experiment) – experimentObjective 4 (Effectiveness in real-world setting) – field studyObjective 5 (Analysis) – Statistical analysis & Simulation

Objective 3

Totally 60 clerical staffs as subjects

Typical office work

Questionnaire: thermal evaluationand behaviours

Gantt Chart

ReferenceStandard, A. S. H. R. A. E. (2010). Standard 55-2010:“Thermal Environmental Conditions for Human Occupancy”; ASHRAE. Atlanta USA.

Karjalainen, S., & Koistinen, O. (2007). User problems with individual temperature control in offices. Building and Environment, 42(8), 2880-2887.

Dantsiou, D. and Sunikka-Blank, M. (2015). Why does energy use feedback not work in workplaces? Insights from social practice theory. ECEEE 2015 Summer Study - First Fuel now, Toulon, France, 2227-2236

Zhang, H., Arens, E., & Zhai, Y. (2015). A review of the corrective power of personal comfort systems in non-neutral ambient environments. Building and Environment, 91, 15-41.

Arens, E., Xu, T., Miura, K., Hui, Z., Fountain, M., & Bauman, F. (1998). A study of occupant cooling by personally controlled air movement. Energy and buildings, 27(1), 45-59.

Zhai, Y., Zhang, H., Zhang, Y., Pasut, W., Arens, E., & Meng, Q. (2013). Comfort under personally controlled air movement in warm and humid environments. Building and environment, 65, 109-117.

Zhang, H., Arens, E., Kim, D., Buchberger, E., Bauman, F., & Huizenga, C. (2010). Comfort, perceived air quality, and work performance in a low-power task–ambient conditioning system. Building and Environment, 45(1), 29-39.

Goldstein, N. J., Cialdini, R. B., & Griskevicius, V. (2008). A room with a viewpoint: Using social norms to motivate environmental conservation in hotels. Journal of consumer Research, 35(3), 472-482.

Murray, D. M., Johnson, C. A., Luepker, R. V., & Mittelmark, M. B. (1984). The Prevention of Cigarette Smoking in Children: A Comparison of Four Strategies1. Journal of Applied Social Psychology, 14(3), 274-288.

Keizer, K., Lindenberg, S., & Steg, L. (2011). The reversal effect of prohibition signs. Group processes & intergroup relations, 14(5), 681-688.

Schultz, P. W., Messina, A., Tronu, G., Limas, E. F., Gupta, R., & Estrada, M. (2016). Personalized normative feedback and the moderating role of personal norms: A field experiment to reduce residential water consumption. Environment and Behavior, 48(5), 686-710.

Thank you!