The role of parenthood in worry about overheating in homes and implications for energy use - two online survey studies from the UK and the US

Climate change brings an increase in temperatures and a higher frequency of heatwaves. Both have been linked to a rise in suicide rates and violent crime on a population level. However, little is known about the link between mental health and ambient temperatures on an individual level and for particular subgroups. Overheating poses health risks to children and can cause disturbed sleep; leading to the expectation that parents are more worried about their homes getting too hot than non-parents. We conducted two online survey studies (N = 1000 each) in the UK and the US to understand to what extent parents and an age-matched comparison group without children are worried about overheating and how they differ in their mitigation actions. Findings did not support the main hypotheses around greater overheating concern amongst parents in general, mothers or those with very young children. However, parents indicated a greater likelihood to upgrade / install air-conditioning (US) and to get electric fans (UK). Parents in the UK indicated using more mitigation options to cope with overheating and parents in the US, whilst not reporting doing more actions, were more likely to use air-conditioning to deal with overheating than non-parents. Finally, those parents who mentioned health impacts for children as a reason for concern about overheating, were more concerned about overheating than parents who had other reasons than children’s health as a reason for being concerned about overheating. In summary, being or becoming a parent might have implications for cooling energy use and parental concern; however, many open questions remain

Emotions and thermal comfort – feeling warmer when feeling happier

Providing thermal comfort (TC) in buildings typically uses around 30% of developed nations’ energy and carbon emissions. Thermal comfort is provided by constraining ambient temperatures to within narrowly defined ‘comfortable’ ranges traditionally based on physiological heat balance models of the human body. Our understanding of what drives thermal comfort perception is still limited however, and while physiological parameters have been identified for decades, research on psychological parameters of comfort is still rather limited. The basic emotions have not been studied in relationship to thermal comfort, so in this study, we investigated the relationship between emotional state, i.e. feeling happy or sad, and thermal comfort perception. A recent study has shown that the various basic emotions are associated with specific perceived activation state of the body (Nummenmaa, Glerean, Hari, & Hietanen, 2014) which we hypothesized would translate in different comfort states. Feeling happy would, through higher perceived bodily activation, translate to feeling warmer or more thermally comfortable - whereas feeling sad would lead to feeling colder or less thermally comfortable, because of the associated perceived lower bodily activation. We designed an experimental study using Amazon Mechanical Turk (Paolacci, Chandler, & Ipeirotis, 2010). N = 300 Turkers were recruited and randomly assigned to recall either a happy autobiographical episode or a sad one to induce a happy or sad emotional state (Briñol, Petty, & Barden, 2007). The valid sample encompassed N = 273. A manipulation check revealed that the emotional manipulation worked. There was a significant effect of emotional state on the standard ASHRAE comfort survey question “How are you feeling in this moment from 1 (cold) to 7 (hot)?”. Those feeling happy reported feeling significantly warmer than those feeling sad [t(269) = 3.66, p < .001]. However, there was no difference in the two other outcomes variables, estimate of room temperature and rating of how thermally comfortable one felt - the latter also being a standard thermal comfort survey question. We conclude that there is some evidence for a relationship between emotional state and thermal perception in feeling of warm or cold that warrants further research on this topic. The data also indicate a dissociation between various thermal comfort related outcomes measures, posing a methodological challenge that needs addressing

Comparison of indoor temperatures of homes with recommended temperatures and effects of disability and age: an observational, cross-sectional study.

OBJECTIVES: We examine if temperatures in winter in English homes meet the recommendation of being at least 18°C at all times. We analyse how many days meet this criterion and calculate the hours per day and night being at/above 18°C. These metrics are compared between households with occupants aged above 64 years or having a long-term disability (LTD) and those younger and without disability. DESIGN: Cross-sectional, observational. SETTING: England. PARTICIPANTS: 635 households. OUTCOMES MEASURES: (1) Mean temperatures, (2) proportion of days of the measurement period meeting the criterion, (3) average hours at/above 18°C, (4) average hours at night at/above 18°C. RESULTS: Mean winter temperatures in the bedroom were MBR=18.15°C (SD=2.51), the living room MLR=18.90°C (SD=2.46) and the hallway MHall=18.25°C (SD=2.57).The median number of days meeting the criterion was 19-31%. For the living room, more days meet the criterion in the group with a LTD (Mdisability=342 vs Mno_disability=301, 95% CI 8 to 74), and with someone over 64 years present (Mabove64=341, Mbelow65=301 95%, CI 8 to 74).The median number of hours/day meeting the criterion was 13-17. In the living room, households with a disability had more hours at 18°C (Mdisability=364, Mno_disability=297, 95% CI 17 to 83) as did the older age group (Mabove64=347, Mbelow65=296, 95% CI 18 to 84). In the hallway, more hours met the criterion in households with a disability (Mdisability=338, Mno_disability=302, 95% CI 3 to 70).247 homes had at least nine hours of at least 18°C at night; no effect of age or disability. CONCLUSIONS: Many households are at risk of negative health outcomes because of temperatures below recommendations

Saving energy through changing light: The impact of illumination on thermal comfort

The ‘Hue-Heat Hypothesis’ states that light with wavelengths predominantly at the red end of the spectrum (or of a low colour temperature) are felt as warmer, whilst light with wavelengths mainly in the blue end (or of a high colour temperature) are felt as cooler. If confirmed, the Hue-Heat-Hypothesis could be a powerful tool for energy savings: Temperatures could be lowered under a reddish light in the heating season. Conversely, less air-conditioning might be needed during the cooling season if higher temperatures were accepted under a bluish light. Even a transitory effect would be beneficial in managing power demand by allowing building temperatures to drift over a wider range of temperatures before heating or cooling was required. We used an experimental design to study the Hue-Heat-Hypothesis. Testing took place in a climate chamber, in which ambient temperature, relative humidity, and air speed can be controlled. We installed a LED-lighting system in the chamber covering the range of correlated colour temperatures from 2700K, a warm, reddish light, to 6500K which appears bluish-cold. Participants (age range 18 to 35 years) were exposed to combinations of colour temperature and ambient temperature and completed standard thermal comfort surveys at specific time-points. Prior to testing, participants filled in a survey that asked about other factors potentially impacting on thermal comfort. In Study 1, temperature in the climate chamber was cooled continuously from 24°C to 20°C over a 60-minute period. Comfort ratings were obtained every 10 minutes. Participants (N = 32) were either exposed to a colour temperature of 2700K or 6500K (between-subjects design). Thermal comfort was higher under the warm colour temperature (2700K) than under the cold one (6500K). This difference was particularly pronounced for temperatures around 21 and 22°C. For the same subjective thermal comfort rating, ambient temperatures differed by around half a degree under the different lighting conditions. The magnitude of the effect varied with temperature (greatest effects observed around 22-23˚C) and by comfort question asked. In Study 2, a within-subject design was used. Subjects were exposed to three different lights (2700K, 4440K,6500 K) with temperature decreasing from 23°C to 19°C. Preliminary results were similar to those of Study 1 with higher comfort under the warm-appearing light. Comfort ratings under the medium colour temperature of 4400K were positioned between the higher ratings obtained for 2700K and lower ratings for 6500K, again, only in a limited corridor of ambient temperature. In Study 3, light was changed gradually from a cold to a warm colour temperature whilst ambient temperature decreased from 23°C to 19°C. Testing is on-going, but initial results indicate that the changes in self-reported comfort under decreasing temperatures are slower in the condition of changing light dynamically than under a stable Our studies support the Hue-Heat-Hypothesis. Varying the ambient light has an effect on thermal comfort and hence may be a suitable tool for energy savings and reducing of peak power demand

Evaluating assumptions of scales for subjective assessment of thermal environments – Do laypersons perceive them the way, we researchers believe?

International audienc

Conceptual and Visual Features Contribute to Visual Memory for Natural Images

We examined the role of conceptual and visual similarity in a memory task for natural images. The important novelty of our approach was that visual similarity was determined using an algorithm [1] instead of being judged subjectively. This similarity index takes colours and spatial frequencies into account. For each target, four distractors were selected that were (1) conceptually and visually similar, (2) only conceptually similar, (3) only visually similar, or (4) neither conceptually nor visually similar to the target image. Participants viewed 219 images with the instruction to memorize them. Memory for a subset of these images was tested subsequently. In Experiment 1, participants performed a two-alternative forced choice recognition task and in Experiment 2, a yes/no-recognition task. In Experiment 3, testing occurred after a delay of one week. We analyzed the distribution of errors depending on distractor type. Performance was lowest when the distractor image was conceptually and visually similar to the target image, indicating that both factors matter in such a memory task. After delayed testing, these differences disappeared. Overall performance was high, indicating a large-capacity, detailed visual long-term memory

Energy saving practices, barriers against and reasons for change among social housing tenants

The poster shows results of a survey on energy saving practices, perceived barriers to and motivation for change. This knowledge is essential in designing adequate behaviour-focused interventions to save energy. Social housing tenants constitute an important target group as they are more likely to suffer from fuel poverty, and have little control over stock condition. Tenants report engagement in energy-saving behaviours, and willingness to engage in energy-saving practices. Perceived barriers to change are mainly having an established habit of behaviour and a lack of knowledge. Money was not reported as a stronger motivator for saving energy than protecting the environment or securing a liveable planet for future generations. Replacing habits and providing more information on energy saving are thus important steps towards lower energy consumption. Analysis of stock condition and of actual consumption needs to show if reduction via behaviour change are possible