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This article presents the results of a meta-analysis of hourly indoor summertime temperature datasets gathered during the summer of 2013 (May to September) from 63 dwellings located across the UK. The sample consisted of unmodified dwellings (existing), dwellings with varying levels of fabric improvements (retrofitted), and dwellings constructed to higher levels of the Code for Sustainable Homes (new). Indoor and outdoor temperature data from bedrooms and living rooms from these homes were collected at 5-min intervals using temperature sensors. These data were processed and analyzed for summertime overheating, using both static criteria (CIBSE Guide A) and the criteria associated with the EN 15251 adaptive thermal comfort model (CIBSE TM52). The results show that despite a relatively cool summer, sufficiently high temperatures were found in a high proportion of dwellings, which were overheated according to the static criteria, although the prevalence of overheating was found to be much lower when assessed by the adaptive method. Considerably higher temperatures were found in bedrooms, much higher than those in living rooms. Interestingly, dwellings with higher levels of insulation experienced overheating twice as frequently as uninsulated dwellings. It is necessary to consider the overheating risk during the design and retrofit of homes to avoid air-conditioning in future. [ABSTRACT FROM AUTHOR]

City authorities, community groups and retrofit installers need to identify suitable local areas and dwellings for installing energy retrofit measures. This paper presents a localised Geographical Information System (GIS) based approach that utilizes publicly-available national and local datasets on housing and energy to provide targeted low carbon measures across UK cities. The study uses a rapid city-level energy assessment approach to spatially identify suitable neighbourhoods for particular retrofit measures, based on relative energy use and fuel poverty ratings. A GIS-based carbon mapping model (called DECoRuM) is then used to estimate energy use and potential for energy reduction on a house-by-house level. The improvement measures are aggregated to encourage bulk installations and drive down installation costs. To identify an appropriate neighbourhood case study area, publicly available datasets were assessed for the town of Bicester (Oxfordshire, UK), which included Ordnance Survey Mastermap, Energy Performance Certificate data (EPC) and sub-national energy statistics available at lower layer super output area (LSOA). When the EPC data for Bicester were compared with the sub-national statistics for Bicester, the average difference was found to be ∼800 kWh. This is interesting as EPCs represent dwelling specific but modelled data whereas sub-national datasets represent actual but aggregated data. Superimposing the above datasets, a neighbourhood in southwest Bicester was selected as having the highest percentage of dwellings with energy consumption >300 kWh/m 2 /yr (EPC), most dwellings in need of wall insulation (EPC), second highest mean total energy consumption (sub-national), and third highest percentage of fuel poor dwellings (sub-national). House-level energy assessment in the selected area using DECoRuM showed that a package based approach comprising fabric and heating system upgrade and solar PVs emerged as the most effective. [ABSTRACT FROM AUTHOR]

This paper presents the methodological approach and findings of a simulation study of advanced energy conservation, generation and management technologies applied to two case study dwellings in the UK, so as to achieve net zero energy (NZE) target that includes a reduction of net regulated energy (HVAC) to 0 kWh/m 2 per year and energy generation of at least 50 kWh/m 2 per year. The performance of the dwellings are also tested for a change in energy use and risk of summertime overheating in future climates in the short (2030s), medium (2050s) and long term (2080s). The findings indicate that to meet the NZE targets, regulated loads need to reduce by about half (over current Building Regulations) with community (rather than building-level) renewables playing a major role. It is also found that the NZE targets, given current regulations, are not particularly difficult to achieve in design with regard to energy efficiency but are highly expectant with regard to renewable energy. Further, summertime overheating is projected to be a risk for net zero energy dwellings by the 2050s. Despite this the regulated energy use of both dwellings is projected to reduce by 11 kWh/m 2 /yr, accompanied by a small increase in renewable generation (2 kWh/m 2 /yr). [ABSTRACT FROM AUTHOR]

This paper uses a socio-technical building performance evaluation (BPE) approach to assess the pre- and post- actual performance of two discrete deep low energy retrofits in the UK – a Victorian solid-wall house and modern 1990s cavity-wall house. A ‘low-energy first, then low-carbon’ approach was adopted in both cases, to achieve an 80% reduction in annual CO 2 emissions. Pre-retrofit, both houses had lower measured annual gas consumption as compared to predictions made by energy models, although the electricity consumption in the modern house was higher than modelled, due to occupancy pattern and occupant behaviour. Post-retrofit, it was found that the Victorian house achieved nearly 75% CO 2 reduction, while the modern house achieved only 57% CO 2 reduction over the baseline emissions. Key reasons were higher than expected air permeability rates, installation issues with micro-renewable systems, lack of proper commissioning, usability of controls, occupant preferences and behaviour. Despite the gap between expected and actual carbon emissions, occupant comfort and satisfaction was significantly improved across both retrofits. This evidence-based understanding of the process and outcomes of deep low carbon retrofits is vital not only for learning and innovation, but also for scaling-up deep retrofit programmes for meeting national and international carbon targets. [ABSTRACT FROM AUTHOR]

This paper presents a systematic, socio-technical and empirical evaluation of the actual energy and environmental performance of a sustainably-designed institutional building (Southeast England), intended to be a teaching tool and ‘living laboratory’ of sustainability. Despite the building being designed to high sustainability standards (Energy Performance Certificate rating of A, low reliance on fossil fuels, natural ventilation and rainwater harvesting) and also being under-utilised during the in-use stage (lower hours of occupation and number of occupants), its actual energy-related carbon dioxide-equivalent emissions are four times more than predicted. This is due to poor energy management of the building, underperformance of the biomass boiler and wasteful energy practices in terms of excessive winter overheating in the atrium, inappropriate lighting controls, and electrical equipment being left on standby. Due to lack of training and understanding of the energy manager, the building management system was not used adequately and issues with installation, commissioning and maintenance of the biomass boiler led to its disuse; however the photovoltaic system generated electricity as expected. Findings from the study show how a mixed-methods approach of building performance evaluation (BPE) should be embedded as part of the build process, to ensure that performance outcomes are met in reality. [ABSTRACT FROM AUTHOR]

• Domestic energy mapping can rapidly and accurately target appropriate dwellings. • Dwelling-level data collection by local community improved input for energy model. • Multiple routes of targeting using high energy use, fuel poverty and typologies. • Projected 89–94% mean energy reduction using whole house retrofit package. • Funding programmes need to be customised for different household segments. A long-standing challenge for area-based mass retrofits has been the ability to rapidly and accurately target appropriate dwellings for energy improvements. This paper demonstrates the application of a data-driven localised Geographical Information System (GIS)-based domestic energy mapping approach to create house-by-house baseline energy models and predict the potential for whole house energy retrofits in a case study of 431 dwellings in Oxford (UK). Top - down spatial datasets on energy, housing, socioeconomics and fuel poverty are combined with bottom-up energy modelling underpinned by actual dwelling details gathered through questionnaire surveys by the local community group. Multiple routes to identify suitable dwellings were tested such as grouping dwellings with high energy use, those with high levels of fuel poverty and by common dwelling characteristics. About 300 dwellings were found to be suitable for a whole house retrofit package, equating to 89–94% mean energy reduction over baseline. While the most common dwelling typology, 1930s semi-detached had high retrofit need, it fell in an area with low annual household income. The second most common dwelling typology, 1930s terrace, was dominant in areas with median level of household income. Funding programmes will need to be customised for different household segments to increase the take-up of energy retrofits. [ABSTRACT FROM AUTHOR]

There has been increasing recognition that climate change may lead to risk of summertime overheating in UK dwellings with potentially adverse consequences for human comfort and health. This paper investigates the magnitude of summertime overheating over one month in 2017, in four new flats built to identical thermal standards, with similar occupancy patterns and located in the same block in a development in Southeast England. Both static and adaptive methods were used to assess the overheating risk, while the variation in indoor temperatures across the flats was examined through key building characteristics including floor level, glazing orientation, exposed surface area to floor area ratio (SA/FA), glazing area to floor area ratio, and ventilation. Data collection included continuous monitoring of indoor and outdoor temperature, relative humidity, CO2 levels and opening/closing of windows. Summertime overheating was found to be prevalent in all four flats but was most pronounced in two top floor flats with high SA/FA ratio and east/west facing glazing. Due to limited window opening and locational limitations of one flat, some conclusions were derived from three flats. Though the study sample is small, it is clear that overheating in new housing is a current issue and designing for avoidance of summertime overheating should become mainstream. [ABSTRACT FROM AUTHOR]