• Energy Research

Abstract This paper compares the central heating settings and the heating energy use performance of six flats and two houses built to low energy standards (Code for Sustainable Homes Levels 4 and 5) with a near identical flat and house built to minimum compliance only (2006 Building Regulations). As low energy houses are only recently emerging in the United Kingdom’s social housing stock, and even fewer are subject to Post Occupancy Evaluation, little is known about their performance in terms of heating behaviour and energy demand. The results show that in general, the mean weekday and weekend setpoint temperatures, heating durations and heating energy use are lower in the low energy dwellings compared to the building regulations dwellings.

This paper investigates the opportunities and barriers to business engagement in the UK domestic retrofit sector. There are approximately 28 million UK dwellings accounting for 30% of UK total energy consumption. Almost all of the existing housing stock will require some form of retrofit in order to meet the UK Government’s Net Zero emissions target by 2050. However, adoption has been much lower than required. Semi-structured interviews were undertaken with industry professionals to investigate the key barriers and opportunities for businesses in the retrofit market. The results suggest that there is significant opportunity for businesses, but engagement has been suppressed by three main categories of barriers: (1) Those that cause lack of consumer demand; (2) Those that constrain retrofit projects, limiting their volume and scalability; (3) Those resulting from a lack of government will or direction. Business opportunity for retrofit was seen to extend globally, with substantial market growth possible. The paper suggests potential roles and solutions key stakeholders could take to achieve the volume of retrofit required. The findings should be of interest to all stakeholders who wish to overcome the multitude of barriers to business engagement in the retrofit sector and realise the potential opportunities. Practical application: This study aims to understand the barriers preventing the large-scale adoption of domestic retrofit in the UK in order to identify avenues for increasing business engagement in the sector. Potential areas believed to present significant opportunity for businesses when engaging in, developing and upscaling the retrofit process and solutions are highlighted. This paper should be of interest to building industry professionals already or wanting to undertake domestic retrofit works in future. The paper also gathers the views of current building industry professionals through semi-structured interviews providing an industry centric assessment of the sector’s challenges and possible solutions.

Abstract The construction sector accounts for a significant portion of the total final energy use and carbon emissions worldwide. Despite efforts to reduce energy consumption through energy efficiency improvements in buildings, the measures proposed by the construction sector are falling short. Among several causes which lead buildings to perform differently to what was defined in the design stage, commonly referred to as the ‘energy performance gap’, the occurrence of quality defects has been acknowledged. This paper aims to identify through an in-depth literature review, quality defects which undermine the thermal performance of buildings by comparing the studies’ findings with regard to defect characteristics and attributes; major causes and influencing factors; and their impact on the energy performance of construction projects. This review also aims to highlight areas where more research is needed if the expected thermal performance of buildings is to be achieved. Understanding the generation process and effects of defects on the energy efficiency of buildings can support the implementation of appropriate quality management systems in construction projects and thus contribute to the achievement of the intended energy performance targets.

Concerns about climate change associated with the combustion of fossil fuels urge a call for widespread reductions in household energy use. Determining means of achieving this is a key challenge faced by environmental scientists. The current research presents insights gained from a 12-month empirical trial of new serious game for energy, ‘EnergyCat’; which was designed to encourage household energy reductions in the UK social housing sector. Effects of gameplay on consumption behaviours and energy awareness were explored using 82 UK social housing households (versus a no-game control). Results indicated the intervention did not lead to any substantive changes in awareness or consumption practices. However, post-intervention feedback highlighted several issues in terms of game design and usability that may explain why the game failed to change behaviour in this instance. We provide a framework of suggestions as to how the game design process could be improved in order to engage residents in future, including use of adaptive fonts for older residents, and provision of clearer instructions on gameplay objectives at the outset. In addition, researchers should ensure close collaboration is maintained with residents throughout the design process in future efforts, in order to maximise likelihood of ongoing engagement from this population.

Abstract This paper presents essential empirical data on heating setpoint temperatures and durations from UK social housing built to low energy standards. The data was derived from living room air temperature measurements. There were single, double and multiple heating periods per day in the dwellings with mean setpoint temperatures of 20.9°C and 21.0°C on weekdays and weekends respectively. The weekday mean heating duration was 8.4 hours and for weekends, it was 9.1 hours. The results could be used to better inform the assumptions of space heating behaviour used in energy models in order to more accurately predict the space heating energy demands of dwellings.

Abstract This paper presents the development of stochastic models of occupants' main bedroom window operation based on measurements collected in ten UK dwellings over a period of a year. The study uses multivariate logistic regression to understand the probability of opening and closing windows based on indoor and outdoor environment factors (physical environmental drivers) and according to the time of the day and season (contextual drivers). To the authors' knowledge, these are the first models of window opening and closing behaviour developed for UK residential buildings. The work reported in this paper suggests that occupants' main bedroom window operation is influenced by a range of physical environmental (i.e. indoor and outdoor air temperature and relative humidity, wind speed, solar radiation and rainfall) and contextual variables (i.e. time of day and season). In addition, the effects of the physical environmental variables were observed to vary in relation to the contextual factors. The models provided in this work can be used to calculate the probability that the main bedroom window will be opened or closed in the next 10 min. These models could be used in building performance simulation applications to improve the inputs for occupants' window opening and closing behaviour and thus the predictions of energy use and indoor environmental conditions of residential buildings.

The application of gamification to encourage energy conservation behaviour in house occupants is an emerging field of research. However, empirical evidence of its effectiveness is lacking. This paper presents lessons learnt from the EU-funded EnerGAware research project, in which an innovative serious game (a game designed for purposes other than purely entertainment) was developed to promote reduced energy consumption and carbon emissions by changing social housing tenants’ energy efficiency behaviour. The game was validated in a sample of European social housing using a longitudinal, two-stage experimental design, employing both pre-post and control group approaches. While some aspects of the game did not work as intended, there were nevertheless some positive impacts. The intervention increased social housing tenants’ awareness and engagement in certain energy saving behaviour and provided an average electricity saving of 3.46% and an average gas saving of 7.48%. Although savings were found not to be statistically significant, an effect size was detected (0.2). Therefore, future steps should exploit all available opportunities to replicate the pilot and increase the sample size so as to gain stronger evidence of the game’s impact. Preliminary results support the utility of gaming investment in the household energy efficiency field, and provide useful insights and pathways that could be incorporated into the development of future serious game interventions to foster their effectiveness. Peer Reviewed