The role of thermostatic radiator valves for the control of space heating in UK social-rented households

This paper provides an analysis of the relationships between dwelling, household and motivation, behaviour and perception characteristics and thermostatic radiator valve (TRV) settings in living rooms (n = 187) and bedrooms (n = 159) in UK social housing. The work capitalises on primary data from a socio-technical household survey undertaken in Plymouth, UK during 2015, which was coupled with building audit data. The mean reported TRV setpoint temperatures in the living rooms and bedrooms were 23.4 °C and 21.9 °C, implying that occupants prefer cooler conditions in bedrooms. There were systematic variations according to dwelling, household, and motivation, behaviour and perception characteristics. In general, the setpoint temperatures in individual rooms were higher than the whole house thermostat setpoint temperature, implying that there may be a misunderstanding of the role of TRVs in the home heating system. The research could enable social housing providers, the government and commercial organisations to target energy efficiency measures (i.e. thermal upgrades) and social interventions (i.e. behaviour change) at those dwellings and households where their impact may be most beneficial. The results presented could also be used to improve the assumptions of zonal heating behaviour in energy models, which could result in more realistic predictions of the heating demands of social housing.

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title: A national field survey of house temperatures
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title: Estimating space heating determinants: An analysis of Greek households
abstract: The purpose of this paper is to estimate the main determinants of households’ residential consumption for space heating in Greece employing cross-section data for 2003. In the empirical analysis household space heating consumption models are employed, using OLS, probit, tobit and quantile regression techniques. The results show that demographic and economic variables such as age of the respondent, family size and households’ annual income are suitable to explain differences towards oil consumption for space heating. In addition, the results suggest that dwelling's size and rate of occupancy are positively associated with the amount of oil that Greek households consumed in order to achieve a significant level of heat comfort for their house. By evaluating household's decision-making process with regard to space heating consumption we are able to propose an effective energy policy framework.

title: Domestic energy consumption—What role do comfort, habit, and knowledge about the heating system play?
abstract: Abstracts The aim of this study was to gain a better understanding of human factors potentially related to energy consumption in domestic households. In particular, the focus was on the meaning of comfort and comfort actions, barriers to and motivators for saving energy, and knowledge about the heating system. Data were collected using surveys, interviews, and monthly energy meter readings. The data of the main sample, social housing tenants, were supplemented by a sample of University staff to test if similar results would be obtained in two very different samples. Findings largely overlapped in the two groups. In summary, the main results were that (1) warmth was given most often as the meaning of comfort, (2) comfort practices were to a large extent defined as temperature-related actions with low energy use, (3) a deficit in the quality and quantity of instruction on how to use the heating system was reported, (4) being used to behaving in a certain way was seen as the most important barrier to behaviour change and was also related to actual energy consumption and self-reported energy consumption actions, and (5) willingness for behaviour change was greatest in order to save money.

title: How People Actually Use Thermostats
abstract: Residential thermostats have been a key element in controlling heating and cooling systems for over sixty years. However, today’s modern programmable thermostats (PTs) are complicated and difficult for users to understand, leading to errors in operation and wasted energy. Four separate tests of usability were conducted in preparation for a larger study. These tests included personal interviews, an on-line survey, photographing actual thermostat settings, and measurements of ability to accomplish four tasks related to effective use of a PT. The interviews revealed that many occupants used the PT as an on-off switch and most demonstrated little knowledge of how to operate it. The on-line survey found that 89% of the respondents rarely or never used the PT to set a weekday or weekend program. The photographic survey (in low income homes) found that only 30% of the PTs were actually programmed. In the usability test, we found that we could quantify the difference in usability of two PTs as measured in time to accomplish tasks. Users accomplished the tasks in consistently shorter times with the touchscreen unit than with buttons. None of these studies are representative of the entire population of users but, together, they illustrate the importance of improving user interfaces in PTs.

title: On the control of heating systems in the UK
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