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As governments worldwide address the climate crisis, energy systems are becoming both decarbonised and decentralised. In this study, we aim to increase understanding of the spatial dimensions of new forms of decentralised energy systems that integrate electricity, storage, transportation, and heating. Drawing on workshops and secondary data from three, early-stage case studies funded under a UK government programme, we examine how stakeholders responsible for development construct the ‘local’ in Smart Local Energy System (SLES) demonstrators. We employ three analytical concepts to address this aim: emplacement, place-framing, and place/boundary-making. In terms of emplacement, stakeholders use place-based narratives that draw on distinctive infrastructural, social, ecological, and political characteristics to argue that diverse locations (Oxford city, Oxfordshire, and the Orkney Islands) are ‘suitable’ places for decentralised energy. Stakeholders frame projects around non-local goals of creating technological and business models for replication across the UK and worldwide, even if some community-centred benefits are recognized. Lastly, our findings on place-making show pragmatism in flexing ‘local’ boundaries in order to align with project objectives. The three analytical concepts provide a useful framework to uncover ‘local’ complexities of early-stage decentralised energy projects, and emphasise intersections of space, place, and justice that deserve further scrutiny, notably in later stages of project implementation.
Chad Walker; Patrick Devine-Wright; Melanie Rohse; Luke Gooding; Hannah Devine-Wright; Rajat Gupta. What is ‘local’ about Smart Local Energy Systems? Emerging stakeholder geographies of decentralised energy in the United Kingdom. Energy Research & Social Science 2021, 80, 102182 .
AMA StyleChad Walker, Patrick Devine-Wright, Melanie Rohse, Luke Gooding, Hannah Devine-Wright, Rajat Gupta. What is ‘local’ about Smart Local Energy Systems? Emerging stakeholder geographies of decentralised energy in the United Kingdom. Energy Research & Social Science. 2021; 80 ():102182.
Chicago/Turabian StyleChad Walker; Patrick Devine-Wright; Melanie Rohse; Luke Gooding; Hannah Devine-Wright; Rajat Gupta. 2021. "What is ‘local’ about Smart Local Energy Systems? Emerging stakeholder geographies of decentralised energy in the United Kingdom." Energy Research & Social Science 80, no. : 102182.
This paper brings together objective and subjective data on indoor temperature and thermal comfort to examine the magnitude and perception of summertime overheating in two London-based care homes occupying modern and older buildings. Continuous monitoring of indoor and outdoor temperature, relative humidity and CO2 levels was conducted in summer 2019 along with thermal comfort surveys and semi-structured interviews with older residents and staff of the care settings. Indoor temperatures were found to be high (>30°C) with bedroom temperatures often higher at night than daytime across both care settings. Limited opening due to window restrictors constrained night-time ventilation. Overheating was prevalent with four out of the five monitored bedrooms failing all four overheating metrics investigated. While 35–42% of staff responses perceived indoor temperatures to be uncomfortably hot, only 13–19% of resident responses were found to do so, indicating that elderly residents tend to be relatively insensitive to heat, leaving them open to overheating without realising it. Residents and staff in the modern care setting were less satisfied with their thermal conditions. As hybrid buildings, care settings need to keep both residents and staff comfortable and healthy during hot weather through night-time ventilation, management of heating and supportive institutional practices. Practical application: Care home designs have focused on keeping residents warm through the winter, neglecting the risks of summertime overheating. Care homes are hybrid buildings serving as living spaces for vulnerable older residents and offices/workspaces for staff. Providing comfort to both groups during periods of hot weather is challenging. Opportunities for ventilation are limited by Health & Safety regulations that mandate up to 10 cm maximum window openings and institutional practices that result in windows routinely kept closed, particularly at night. Utilising natural and where possible cross-ventilation should be considered along with external shading. Heating should be managed to avoid unwanted heat gains in the summer.
Rajat Gupta; Alastair Howard; Mike Davies; Anna Mavrogianni; Ioanna Tsoulou; Eleni Oikonomou; Paul Wilkinson. Examining the magnitude and perception of summertime overheating in London care homes. Building Services Engineering Research and Technology 2021, 1 .
AMA StyleRajat Gupta, Alastair Howard, Mike Davies, Anna Mavrogianni, Ioanna Tsoulou, Eleni Oikonomou, Paul Wilkinson. Examining the magnitude and perception of summertime overheating in London care homes. Building Services Engineering Research and Technology. 2021; ():1.
Chicago/Turabian StyleRajat Gupta; Alastair Howard; Mike Davies; Anna Mavrogianni; Ioanna Tsoulou; Eleni Oikonomou; Paul Wilkinson. 2021. "Examining the magnitude and perception of summertime overheating in London care homes." Building Services Engineering Research and Technology , no. : 1.
This paper presents the methodology and results of in situ testing of building fabric thermal performance to calibrate as-built energy models of three low-energy dwellings in the UK, so as to examine the gap between as-designed and as-built energy performance. The in situ tests included repeat testing of air permeability (AP) integrated with thermal imaging survey and heat flux measurements of the building fabric elements, along with concurrent monitoring of indoor temperature during the pre-occupancy stage. Despite being designed to high thermal standards, wall and roof U-values were measured to be higher than expected. Thermal imaging surveys revealed air leakage pathways around door/window openings, penetrations and junctions between walls and ceilings, indicating poor detailing and workmanship. AP was found to have increased after the initial test due to post-completion alteration to the building fabric. Though the results did not meet design expectation, they were within the UK Building Regulations. Calibration of energy models with temperature monitoring provided a less extreme energy performance gap than simply replacing the designed values with test results. Insights from this study have reinforced the need for building regulations to require integrated testing of building fabric as part of housing delivery to ensure performance targets are realised.
Rajat Gupta; Matt Gregg. Integrated Testing of Building Fabric Thermal Performance for Calibration of Energy Models of Three Low-Energy Dwellings in the UK. Sustainability 2021, 13, 2784 .
AMA StyleRajat Gupta, Matt Gregg. Integrated Testing of Building Fabric Thermal Performance for Calibration of Energy Models of Three Low-Energy Dwellings in the UK. Sustainability. 2021; 13 (5):2784.
Chicago/Turabian StyleRajat Gupta; Matt Gregg. 2021. "Integrated Testing of Building Fabric Thermal Performance for Calibration of Energy Models of Three Low-Energy Dwellings in the UK." Sustainability 13, no. 5: 2784.
Measurement and verification (M&V) has become necessary for ensuring intended design performance. Currently, M&V procedures and calculation methods exist for the assessment of Energy Conservation Measures (ECM) for existing buildings, with a focus on reliable baseline model creation and savings estimation, as well as for reducing the computation time, uncertainties, and M&V costs. There is limited application of rigorous M&V procedures in the design, delivery and operation of low/zero energy dwellings and settlements. In the present paper, M&V for four pilot net-zero energy settlements has been designed and implemented. The M&V has been planned, incorporating guidance from existing protocols, linked to the project development phases, and populated with lessons learned through implementation. The resulting framework demonstrates that M&V is not strictly linked to the operational phase of a project but is rather an integral part of the project management and development. Under this scope, M&V is an integrated, iterative process that is accompanied by quality control in every step. Quality control is a significant component of the M&V, and the proposed quality control procedures can support the preparation and implementation of automated M&V. The proposed framework can be useful to project managers for integrating M&V into the project management and development process and explicitly aligning it with the rest of the design and construction procedures.
Angeliki Mavrigiannaki; Kostas Gobakis; Dionysia Kolokotsa; Kostas Kalaitzakis; Anna Pisello; Cristina Piselli; Rajat Gupta; Matt Gregg; Marina Laskari; Maria Saliari; Margarita-Niki Assimakopoulos; Afroditi Synnefa. Measurement and Verification of Zero Energy Settlements: Lessons Learned from Four Pilot Cases in Europe. Sustainability 2020, 12, 9783 .
AMA StyleAngeliki Mavrigiannaki, Kostas Gobakis, Dionysia Kolokotsa, Kostas Kalaitzakis, Anna Pisello, Cristina Piselli, Rajat Gupta, Matt Gregg, Marina Laskari, Maria Saliari, Margarita-Niki Assimakopoulos, Afroditi Synnefa. Measurement and Verification of Zero Energy Settlements: Lessons Learned from Four Pilot Cases in Europe. Sustainability. 2020; 12 (22):9783.
Chicago/Turabian StyleAngeliki Mavrigiannaki; Kostas Gobakis; Dionysia Kolokotsa; Kostas Kalaitzakis; Anna Pisello; Cristina Piselli; Rajat Gupta; Matt Gregg; Marina Laskari; Maria Saliari; Margarita-Niki Assimakopoulos; Afroditi Synnefa. 2020. "Measurement and Verification of Zero Energy Settlements: Lessons Learned from Four Pilot Cases in Europe." Sustainability 12, no. 22: 9783.
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.
Rajat Gupta; Matt Gregg. Assessing the Magnitude and Likely Causes of Summertime Overheating in Modern Flats in UK. Energies 2020, 13, 5202 .
AMA StyleRajat Gupta, Matt Gregg. Assessing the Magnitude and Likely Causes of Summertime Overheating in Modern Flats in UK. Energies. 2020; 13 (19):5202.
Chicago/Turabian StyleRajat Gupta; Matt Gregg. 2020. "Assessing the Magnitude and Likely Causes of Summertime Overheating in Modern Flats in UK." Energies 13, no. 19: 5202.
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.
Rajat Gupta; Matt Gregg. Domestic energy mapping to enable area-based whole house retrofits. Energy and Buildings 2020, 229, 110514 .
AMA StyleRajat Gupta, Matt Gregg. Domestic energy mapping to enable area-based whole house retrofits. Energy and Buildings. 2020; 229 ():110514.
Chicago/Turabian StyleRajat Gupta; Matt Gregg. 2020. "Domestic energy mapping to enable area-based whole house retrofits." Energy and Buildings 229, no. : 110514.
This paper uses a case study-based approach to comparatively evaluate the relationship between measured and perceived indoor environmental conditions in two office buildings, one naturally ventilated and one mechanically ventilated, located in south England. Environmental parameters (indoor and outdoor temperature and relative humidity, and indoor CO2 concentration) were continuously monitored at 5-minute intervals over a 19-month period (March 2017 to September 2018). During this time, occupant satisfaction surveys (both transverse and longitudinal) recorded occupant perceptions of their working environment, including thermal comfort, resulting in approximately 5700 survey responses from the two case studies combined. In the NV office, CO2 levels were high (often >2000 ppm) and indoor temperature was both high (>27 °C) and variable (up to 8 °C change in a working day). In contrast, the MV office environment was found to operate within much narrower temperature, RH and CO2 bands. This was particularly evident in the little seasonal variation observed in the CO2 levels in the MV office (rarely above 1200 ppm); whereas in the NV office, CO2 concentrations exceeded 2000 ppm on 12% of working days during the heating seasons and less than 1% in the non-heating season. Despite these differences in measured indoor environmental conditions, occupants’ overall satisfaction with their environment was similar in both buildings. Occupants of the NV building were found to be more tolerant of higher indoor temperatures while neutral thermal sensation corresponded to a higher indoor temperature, indicating the role of adaptation. This has important implications for energy use in managing the indoor environment.
Rajat Gupta; Alastair Howard. Comparative evaluation of measured and perceived indoor environmental conditions in naturally and mechanically ventilated office environments. Building Simulation 2020, 13, 1021 -1042.
AMA StyleRajat Gupta, Alastair Howard. Comparative evaluation of measured and perceived indoor environmental conditions in naturally and mechanically ventilated office environments. Building Simulation. 2020; 13 (5):1021-1042.
Chicago/Turabian StyleRajat Gupta; Alastair Howard. 2020. "Comparative evaluation of measured and perceived indoor environmental conditions in naturally and mechanically ventilated office environments." Building Simulation 13, no. 5: 1021-1042.
This paper describes the development and testing of a building performance evaluation based claims process that underpins a new insurance-backed energy performance warranty for guaranteeing the in-use performance of new homes in the UK. The insurance backed warranty is based on the principle that if there are deficiencies in the building fabric or energy systems (physical factors) of an insured dwelling which causes excessive energy consumption, the insurance will make good those deficiencies. However, excess energy consumption resulting from occupancy factors is not insured. To be able to accurately identify the cause (physical or occupancy factors) of excessive energy use, a socio-technical building performance evaluation based claims process is developed and tested for four low-energy new-build flats located in a development in Southeast England. Data on energy use, environment (temperature, relative humidity, CO2 levels) and occupant behaviour (opening-closing of windows, appliances’ use) were collected using high-frequency energy and environmental data loggers, questionnaires, interviews and activity logging diaries over a full heating season (October 2017–April 2018). The influence of physical (form, location) and occupant factors (occupancy patterns, heating schedules, hot water requirement, use of electrical appliances) on in-use energy consumption was investigated for three end uses: space heating, water heating and electrical appliances. Results suggest that in the four low-energy flats, occupant behaviour does not significantly affect actual space heating demand (which is mainly determined by physical factors), as much as hot water and use of electrical appliances, indicating that in low-energy gas-heated dwellings, excessive gas use is more likely to be eligible for an insurance claim than high electricity use. In future research the claims process could be less invasive using smart meter data to identify the influence of physical or occupant factors.
Rajat Gupta; Matt Gregg; Agnese Salvati. Performance Evaluation Based Claims Process for Insuring Energy Performance of New Dwellings. Sustainable Ecological Engineering Design 2020, 335 -349.
AMA StyleRajat Gupta, Matt Gregg, Agnese Salvati. Performance Evaluation Based Claims Process for Insuring Energy Performance of New Dwellings. Sustainable Ecological Engineering Design. 2020; ():335-349.
Chicago/Turabian StyleRajat Gupta; Matt Gregg; Agnese Salvati. 2020. "Performance Evaluation Based Claims Process for Insuring Energy Performance of New Dwellings." Sustainable Ecological Engineering Design , no. : 335-349.
Sunil Kumar Sansaniwal; Jyotirmay Mathur; Vishal Garg; Rajat Gupta. Review of studies on thermal comfort in Indian residential buildings. Science and Technology for the Built Environment 2020, 26, 727 -748.
AMA StyleSunil Kumar Sansaniwal, Jyotirmay Mathur, Vishal Garg, Rajat Gupta. Review of studies on thermal comfort in Indian residential buildings. Science and Technology for the Built Environment. 2020; 26 (6):727-748.
Chicago/Turabian StyleSunil Kumar Sansaniwal; Jyotirmay Mathur; Vishal Garg; Rajat Gupta. 2020. "Review of studies on thermal comfort in Indian residential buildings." Science and Technology for the Built Environment 26, no. 6: 727-748.
Residential energy (electricity) use in India is expected to grow four-fold by 2030, yet there is paucity of data that is essential for developing energy policy or programme. This paper undertakes a meta-study of residential energy studies in India to characterise their scope, data collection methods and findings. An in-depth review of literature was undertaken using Google Scholar, Web of Science, Scopus and ScienceDirect to identify relevant journal publications, conference papers and reports. A series of expert workshops were held to identify any data gaps and stakeholders' needs. The identified studies were characterised using a meta-data framework that included criteria such as climate, dwelling form, income group, methods and study duration. An online searchable platform (REACT) was created to make the identified studies more accessible using the meta-data criteria. Of the 29 studies identified, only 16 were published in peer-reviewed publications (10 in journals and 6 in conferences proceedings). About 11 studies focussed on dwelling-level energy use, while the remaining used econometric data and statistical modelling at a macro-scale. To develop evidence based energy policies, it is vital to gather empirical data on residential energy in different climatic zones. Robust data sharing policies should be implemented to avoid duplication of effort.
Rajat Gupta; Sanjoli Tuteja; Jyotirmay Mathur; Vishal Garg. Meta-study of residential energy studies in India. IOP Conference Series: Earth and Environmental Science 2020, 410, 012017 .
AMA StyleRajat Gupta, Sanjoli Tuteja, Jyotirmay Mathur, Vishal Garg. Meta-study of residential energy studies in India. IOP Conference Series: Earth and Environmental Science. 2020; 410 (1):012017.
Chicago/Turabian StyleRajat Gupta; Sanjoli Tuteja; Jyotirmay Mathur; Vishal Garg. 2020. "Meta-study of residential energy studies in India." IOP Conference Series: Earth and Environmental Science 410, no. 1: 012017.
Most studies linking indoor environments and productivity have been conducted in controlled, static conditions often unrepresentative of the real world. This paper uses a case-study-based, real-world approach to empirically investigate the link between indoor environment and workplace productivity in a mechanically-ventilated office environment in southern England. Environmental parameters were monitored continuously. Transverse and longitudinal surveys recorded perceptions of the working environment and self-reported productivity. Performance tasks provided proxy measures of performance. Productivity was perceived to decrease when occupants perceived thermal discomfort and stuffy air. Correlations with perceived changes in productivity were stronger for perceived rather than measured environmental conditions, implying occupants’ subjective feelings impacted perceived productivity more than objective environmental conditions. Task scores were 15% lower when conducted at CO2 levels above 800 ppm compared to below 800 ppm. Insights from the study can help to optimize indoor office environments and improve workplace productivity.
Rajat Gupta; Alastair Howard; Sahar Zahiri. Defining the link between indoor environment and workplace productivity in a modern UK office building. Architectural Science Review 2020, 63, 248 -261.
AMA StyleRajat Gupta, Alastair Howard, Sahar Zahiri. Defining the link between indoor environment and workplace productivity in a modern UK office building. Architectural Science Review. 2020; 63 (3-4):248-261.
Chicago/Turabian StyleRajat Gupta; Alastair Howard; Sahar Zahiri. 2020. "Defining the link between indoor environment and workplace productivity in a modern UK office building." Architectural Science Review 63, no. 3-4: 248-261.
This paper uses a case study-based approach to empirically investigate the relationship between indoor environment and workplace productivity in two contrasting office environments: one naturally ventilated, the other mechanically ventilated. Environmental parameters were continuously monitored over 19 months. Transverse and longitudinal surveys recorded occupants’ perception of their working environment and self-reported productivity, while performance tasks (numerical and proofreading) measured cognitive capability as proxy for measured productivity. Indoor temperatures and CO2 concentrations were found to be higher and more variable in the naturally ventilated office. However, the correlation between occupant perception of their indoor environment and perceived productivity was stronger in the mechanically ventilated office. Occupants of the naturally ventilated office were found to be more tolerant of their environment than their counterparts in the mechanically ventilated office. Task performance was affected by indoor environmental conditions such as indoor temperature and CO2 concentration. Interestingly in the naturally ventilated office, the median scores were up to 12% higher for tests conducted at CO2 concentrations The study showed that higher concentrations of CO2 were associated with lower task scores and longer task durations, reinforcing the need for good levels of ventilation in workspaces. It was found that occupants in NV workspaces were able to adapt to a broader range of environmental conditions. Therefore, controlling the indoor environment within narrow ranges (expending significant amounts of energy in the process) may not always be necessary to improve comfort and productivity. On the other hand, controlling indoor environment within a narrow range – as is common in MV workspaces – may be counterproductive, creating occupants who are less tolerant of small changes in their environmental conditions. The study also demonstrates occupant surveys can provide useful feedback on perceived comfort and productivity at relatively low cost. Insights from such surveys can be used to improve indoor environment in workspaces.
Rajat Gupta; Alastair Howard; Sahar Zahiri. Investigating the relationship between indoor environment and workplace productivity in naturally and mechanically ventilated office environments. Building Services Engineering Research and Technology 2019, 41, 280 -304.
AMA StyleRajat Gupta, Alastair Howard, Sahar Zahiri. Investigating the relationship between indoor environment and workplace productivity in naturally and mechanically ventilated office environments. Building Services Engineering Research and Technology. 2019; 41 (3):280-304.
Chicago/Turabian StyleRajat Gupta; Alastair Howard; Sahar Zahiri. 2019. "Investigating the relationship between indoor environment and workplace productivity in naturally and mechanically ventilated office environments." Building Services Engineering Research and Technology 41, no. 3: 280-304.
This paper uses a case study-based approach to comparatively evaluate the relationship between measured and perceived indoor environmental conditions in two office buildings, one naturally ventilated (NV) and one mechanically ventilated (MV) located in southeast England. Environmental parameters (indoor and outdoor relative humidity (RH), CO2 and indoor and outdoor temperature) were continuously monitored at 5 minute intervals over a period of 19 months (March 2017 to September 2018). During the monitoring period, occupant satisfaction surveys (snapshot and longitudinal) were conducted to record occupant perceptions of their working environment, including thermal comfort, resulting in approximately 2600 survey responses from each case study. In the NV office, CO2 levels were high (>2000ppm) and indoor temperature was both high (>27°C) and variable (up to 8°C change). The MV office environment was found to operate within much narrower indoor temperature, RH and CO2 bands. This was evident in the little seasonal variation observed in the indoor CO2 levels in the MV office; whereas in the NV office, CO2 concentrations were over 1400 ppm for 20% of the working hours during the heating seasons and decreasing to 3% in the non-heating seasons, when windows were frequently opened. Occupants were found to have different levels of tolerance to measured indoor temperatures - neutral thermal sensation votes corresponded to a higher indoor temperature in the NV building, indicating the role of adaptation. Insights from the study can help in improving indoor environments of NV and MV offices.
Rajat Gupta; Alastair Howard. Comparative evaluation of the link between measured and perceived indoor environmental conditions in naturally and mechanically ventilated office environments. IOP Conference Series: Materials Science and Engineering 2019, 609, 042080 .
AMA StyleRajat Gupta, Alastair Howard. Comparative evaluation of the link between measured and perceived indoor environmental conditions in naturally and mechanically ventilated office environments. IOP Conference Series: Materials Science and Engineering. 2019; 609 (4):042080.
Chicago/Turabian StyleRajat Gupta; Alastair Howard. 2019. "Comparative evaluation of the link between measured and perceived indoor environmental conditions in naturally and mechanically ventilated office environments." IOP Conference Series: Materials Science and Engineering 609, no. 4: 042080.
This paper 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 five-minute intervals using temperature sensors. These data were processed and analysed for summertime overheating, using both static criteria (CIBSE Guide A) and the criteria associated with the EN15251 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 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.
Rajat Gupta; Matt Gregg; Robert Irving. Meta-analysis of summertime indoor temperatures in new-build, retrofitted, and existing UK dwellings. Science and Technology for the Built Environment 2019, 25, 1212 -1225.
AMA StyleRajat Gupta, Matt Gregg, Robert Irving. Meta-analysis of summertime indoor temperatures in new-build, retrofitted, and existing UK dwellings. Science and Technology for the Built Environment. 2019; 25 (9):1212-1225.
Chicago/Turabian StyleRajat Gupta; Matt Gregg; Robert Irving. 2019. "Meta-analysis of summertime indoor temperatures in new-build, retrofitted, and existing UK dwellings." Science and Technology for the Built Environment 25, no. 9: 1212-1225.
This paper empirically evaluates the extent of energy resilience achieved in a socially-deprived community in Oxford, through deployment of solar photovoltaic (PV) systems and smart batteries (internet enabled and controllable) across a cluster of 82 dwellings (households). The methodological approach comprised dwelling and household surveys, along with high frequency monitoring of household electricity consumption, solar PV generation, battery charge and discharge data. In the monitored households, average daily electricity consumption was found to be positively related with dwelling size, number of occupants and number of appliances used. Although 117MWh of PV electricity was generated within a year across 74 dwellings, peak generation did not match peak consumption, demonstrating the need for battery storage. Home batteries were found to increase self-consumption of PV electricity and offset grid demand through discharge of stored PV electricity marginally at an average of 6%, depending on the size of the PV system, surplus PV electricity available and size of the battery. Aggregating solar generation and storage at a community level showed that peak grid electricity demand between 17:00 and 19:00 was reduced by 8% through the use of smart batteries across 74 dwellings. In future, a local energy sharing scheme could be developed, wherein not all dwellings would need to have solar PV systems, but rather have internet enabled batteries that could be monitored and controlled virtually.
Rajat Gupta; Adorkor Bruce-Konuah; Alastair Howard. Achieving energy resilience through smart storage of solar electricity at dwelling and community level. Energy and Buildings 2019, 195, 1 -15.
AMA StyleRajat Gupta, Adorkor Bruce-Konuah, Alastair Howard. Achieving energy resilience through smart storage of solar electricity at dwelling and community level. Energy and Buildings. 2019; 195 ():1-15.
Chicago/Turabian StyleRajat Gupta; Adorkor Bruce-Konuah; Alastair Howard. 2019. "Achieving energy resilience through smart storage of solar electricity at dwelling and community level." Energy and Buildings 195, no. : 1-15.
The green building movement in India is lacking an important link: ensuring that the design intent of such buildings is actually realized. This paper undertakes an exploratory investigation to develop and test a customized building performance evaluation (BPE) approach (I-BPE framework) for the Indian context. As academia is considered to be an initial primary outlet of BPE, a survey of experts is conducted to investigate the drivers and barriers for implementing BPE-based methods in educational curricula. The I-BPE approach is tested in a case study building to gain insights for refining the underlying methods and processes for conducting further BPE studies in the context of India. The expert survey reveals the lack of trained people for teaching BPE as a key challenge to its adoption, implying that trained people are needed as much as frameworks. To enable widespread adoption of I-BPE in India, what will be necessary is a new cadre of building performance evaluators who can be trained (or up-skilled) through formal or continuing education. This will need to be driven by both policy (energy code) and market transformation (‘green’ rating systems). A series of delivery routes are suggested to enable rapid and deeper learning.
Rajat Gupta; Matt Gregg; Sanyogita Manu; Prasad Vaidya; Maaz Dixit. Customized performance evaluation approach for Indian green buildings. Building Research & Information 2018, 47, 56 -74.
AMA StyleRajat Gupta, Matt Gregg, Sanyogita Manu, Prasad Vaidya, Maaz Dixit. Customized performance evaluation approach for Indian green buildings. Building Research & Information. 2018; 47 (1):56-74.
Chicago/Turabian StyleRajat Gupta; Matt Gregg; Sanyogita Manu; Prasad Vaidya; Maaz Dixit. 2018. "Customized performance evaluation approach for Indian green buildings." Building Research & Information 47, no. 1: 56-74.
This chapter presents a novel localized Geographical Information System (GIS) based approach to rapidly model, map, and manage energy use and carbon emissions on a house-by-house level, from 1659 dwellings located across six low carbon communities in the UK, before and after low carbon community action. Incremental packages of energy saving measures and low carbon technologies are assessed for their impact on energy and carbon reduction to reveal further potential for low energy refurbishment in the local area. The results show that there has been a decrease of about 10%–14% in average annual energy consumption per dwelling from 2008 to 2012 across the six communities, which is likely to be due to improvement measures installed as a result of community action. To achieve further savings, solid wall insulation measure is found to provide the greatest energy reduction amongst individual measures, while a package based approach comprising building fabric improvement, heating system upgrade, and solar photovoltaics emerged as the most effective in reducing carbon emissions. The spatial visualization of the results is considered particularly helpful for local authorities and community groups in planning for future local energy action.
Rajat Gupta; Matt Gregg. Modeling and Mapping Domestic Energy Refurbishment Measures on a Community Scale. Urban Energy Transition 2018, 661 -676.
AMA StyleRajat Gupta, Matt Gregg. Modeling and Mapping Domestic Energy Refurbishment Measures on a Community Scale. Urban Energy Transition. 2018; ():661-676.
Chicago/Turabian StyleRajat Gupta; Matt Gregg. 2018. "Modeling and Mapping Domestic Energy Refurbishment Measures on a Community Scale." Urban Energy Transition , no. : 661-676.
This paper empirically investigates the influence of building fabric, services and occupant related factors on actual energy use of six case study dwellings, located in three new low energy social housing developments in UK, covering a variety of built forms and construction systems (timber frame, hempcrete, steel-frame). Physical monitoring of indoor environment and window-opening is cross-related with building fabric and systems’ performance, and qualitative data gathered through occupant surveys, review of control interfaces and handover guidance, to understand the causes of the gap between modelled and measured energy use. Actual energy use is found to exceed design expectations by a factor of three, questioning the need for whole-house mechanical ventilation heat recovery (MVHR) systems at measured air permeability rates of 6m³/(h.m²) against the design target of 3m³/(h.m²). Lack of proper commissioning of MVHR and heating systems, combined with inadequate user comprehension about their operation and control leads to occupant ‘misuse’ wherein systems are de-activated, thereby negatively affecting indoor air quality. This is confounded by occupant factors related to higher demand temperatures, unexpected opening of windows during winters due to under-performance of MVHR combined with habitual behaviours, and over-use of heating systems to compensate for higher than expected air permeability.
Rajat Gupta; Mariam Kapsali; Alastair Howard. Evaluating the influence of building fabric, services and occupant related factors on the actual performance of low energy social housing dwellings in UK. Energy and Buildings 2018, 174, 548 -562.
AMA StyleRajat Gupta, Mariam Kapsali, Alastair Howard. Evaluating the influence of building fabric, services and occupant related factors on the actual performance of low energy social housing dwellings in UK. Energy and Buildings. 2018; 174 ():548-562.
Chicago/Turabian StyleRajat Gupta; Mariam Kapsali; Alastair Howard. 2018. "Evaluating the influence of building fabric, services and occupant related factors on the actual performance of low energy social housing dwellings in UK." Energy and Buildings 174, no. : 548-562.
This paper presents new evidence from a nationwide cross-project meta-study investigating the magnitude and extent of the difference between designed and measured thermal performance of the building fabric of 188 low energy dwellings in the UK. The dataset was drawn from the UK Government’s national Building Performance Evaluation programme, and comprises 50 Passivhaus (PH) and 138 non-Passivhaus (NPH) dwellings, covering different built forms and construction systems. The difference between designed and measured values of air permeability (AP), external wall/roof thermal transmittance (U-value) and whole house heat loss were statistically analysed, along with a review of thermal imaging data to explain any discrepancies. The results showed that fabric thermal performance gap was widespread especially in terms of AP, although the magnitude of underperformance was much less in PH dwellings. While measured AP had good correlation with measured space heating energy for PH dwellings, there was no relationship between the two for NPH dwellings. The regression analysis indicated that for every 1 m3/h/m2 reduction in designed air permeability, the gap increased by 0.8 m3/h/[email protected] Pa. Monte Carlo analysis showed that likelihood of AP gap was 78% in NPH dwellings designed to 5 m3/h/[email protected] Pa or lower. The study provides useful evidence for improving the fabric thermal performance of new housing through in-situ testing.
Rajat Gupta; Alkis Kotopouleas. Magnitude and extent of building fabric thermal performance gap in UK low energy housing. Applied Energy 2018, 222, 673 -686.
AMA StyleRajat Gupta, Alkis Kotopouleas. Magnitude and extent of building fabric thermal performance gap in UK low energy housing. Applied Energy. 2018; 222 ():673-686.
Chicago/Turabian StyleRajat Gupta; Alkis Kotopouleas. 2018. "Magnitude and extent of building fabric thermal performance gap in UK low energy housing." Applied Energy 222, no. : 673-686.
Rajat Gupta; Matthew Gregg. Targeting and modelling urban energy retrofits using a city-scale energy mapping approach. Journal of Cleaner Production 2018, 174, 401 -412.
AMA StyleRajat Gupta, Matthew Gregg. Targeting and modelling urban energy retrofits using a city-scale energy mapping approach. Journal of Cleaner Production. 2018; 174 ():401-412.
Chicago/Turabian StyleRajat Gupta; Matthew Gregg. 2018. "Targeting and modelling urban energy retrofits using a city-scale energy mapping approach." Journal of Cleaner Production 174, no. : 401-412.