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The building and transportation sectors are responsible for the greatest proportion of energy consumption in cities. While they are intrinsically interlinked with urban built form and density, climate change and technological innovation are having an effect on their relative contributions. This paper aims to develop an optimisation framework to facilitate the identification of the most energy-efficient urban built forms and urban geometry for the future built environment that can be adapted to the changing climate and ongoing technological development. It examines future scenarios for the city of London as a temperate climate zone (as a case study), in 2050, and contrasts it with the present situation. Specifically, the impact of climate change along with the penetration of electric vehicles into the transportation system that can be charged via rooftop photovoltaics is investigated. This study initially develops the geometrical models of four selected urban built forms and, secondly, analyzes their energy performance using an urban energy simulation software. The results, showing the impact of future scenarios on building energy performance, urban built form and density, demonstrate that court and tunnel-court built forms show better energy performance for future development. It is therefore recommended that for future urban developments in London, deep plan court and tunnel-court buildings with a lower number of storeys and a large cut-off angle are more advantageous in terms of building energy to accommodate the expected climate change. Finally, results of simulation trials indicate that the total building energy demand in 2050 is considerably higher than in the present climate as a result of additional cooling load and electric vehicle charging load. [ABSTRACT FROM AUTHOR]

This paper reviews the historical research that has led to widespread policies on compact urban form, in particular, residential development, and collates evidence that demonstrates that dispersed urban form may be more energy efficient than compact form. This is counterintuitive but is supported by both challenging the conventional modelling of energy use of buildings as well as case studies with empirical evidence. The conclusion is that policies on urban form should be driven not by existing technologies but by the disruptive technologies of the future. The increased use in distributed energy generation in urban areas (generally roof-mounted photovoltaics), the growth in ownership of electric vehicles and the potential introduction of smart and micro-grids and the possibility of virtual power plants is changing the impact that energy has on built form and conflicts with current policies for denser, contained and compact development. [ABSTRACT FROM AUTHOR]

The domestic sector uses the majority of the energy consumed in Palestine. The Palestinian Central Bureau of statistics (PCBS) performs periodic statistics regarding the average energy consumption of the households, but there is no up to date breakdown of the energy consumption in the residential sector. The Palestinian energy sector main challenges are the high fuel prices, lack of sustainable consumption and energy insecurity. Developing energy policies and studying the potential of shifting towards more independent and sustainable energy sources need a clear understanding of the current energy consumption. A survey was used to collect relevant quantitative and qualitative data. The total number of households in Hebron who responded to the survey was 322 households. The survey covered physical characteristics of the dwellings, socioeconomic features of the households in addition to the pattern of heating the spaces, quantity and type of fuel used for heating. On average the households heated only 9.2% of the total area of their houses during the winter days. The survey revealed that households spend 3.5%–21.6% of their monthly income on space heating during winter. The main contribution to knowledge of this paper is a regression model to estimate energy consumption based on the data collected from the survey. The regression model is developed with an R 2 adjusted 0.606 indicating 60.6% accuracy of the predicted energy consumed for heating. The regression model depends on 14 parameters which include the type of settlement, physical characteristics of the dwelling that are housing typology, level of thermal insulation of the walls, the main building materials and the housing age. It also depends on socioeconomic parameters which are the family monthly income and the occupancy period. Moreover, the type of the heating system used, the number of heated months and the nominal heated area were influential parameters in this model. The significance of this paper stems from the methodology that propose an alternative to the energy audit and simulation methods. The proposed method can be used in contexts where a combination of energy resources is used with no proper metering system and with the absence of accurate data that is needed for simulation. [ABSTRACT FROM AUTHOR]

This paper presents the findings of a post-occupancy evaluation (POE) applied to a building in the UK. The design of the building was generated through an externally funded research project over two years from 2005 to 2007. The construction of the building was completed in 2010. After a period of occupancy, a POE of the building was carried out in 2015. The POE offered an opportunity to investigate the effect of occupant behaviour on the performance of the building and their level of comfort and satisfaction. We adopted a field survey method to evaluate the comfort and satisfaction of users by asking them a series of questions to analyse how they felt in different parts of the building throughout the course of the year. In our analysis, the users were prompted to provide a subjective measure of the building regarding a range of internal conditions such as air temperature, humidity, air movement, air quality, daylight, artificial light, and noise. The analysis supports the notion that in naturally-ventilated buildings some users may find the building to be hot in summer while cold in winter. The high level of control the users have over the operation of the building contributes to their comfort and satisfaction. The users demonstrated a tendency to be satisfied despite environmental factors and to forgive some aspects of the building which are not performing as they should. The paper offers a perspective on statistical user satisfaction in a low occupancy building and attempts to explain the role of workplace wellbeing on occupant perception of comfort in this case. [ABSTRACT FROM AUTHOR]

The benefits of choosing refurbishment over new build have recently been brought into focus for reducing environmental impacts of buildings. This is due to the fact that the existing buildings will comprise the majority of the total building stocks for years to come and hence will remain responsible for the majority of greenhouse gas emissions from the sector. This paper investigates the total potentials of sustainable refurbishment and conversion of the existing buildings by adopting a holistic approach to sustainability. Life Cycle Assessment (LCA) and questionnaires have been used to analyse the environmental impact savings (Co2e), improved health and well-being, and satisfaction of people living in refurbished homes. The results reported in the paper are based on a two year externally funded research project completed in January 2013. [ABSTRACT FROM AUTHOR]

Abstract: Building energy use accounts for almost 50% of the total CO2 emissions in the UK. Most of the research has focused on reducing the operational impact of buildings, however in recent years many studies have indicated the significance of embodied energy in different building types. This paper primarily focuses on illustrating the relative importance of operational and embodied energy in a flexible use light distribution warehouse. The building is chosen for the study as it is relatively easy to model and represents many distribution centres and industrial warehouses in Europe. A carbon footprinting study was carried out by conducting an inventory of the major installed materials with potentially significant carbon impact and material substitutions covering the building structure. Ecotect computer simulation program was used to determine the energy consumption for the 25 years design life of the building. This paper evaluates alternative design strategies for the envelope of the building and their effects on the whole life emissions by investigating both embodied and operational implications of changing the envelope characteristics. The results provide an insight to quantify the total amount of CO2 emissions saved through design optimisation by modeling embodied and operational energy. [Copyright &y& Elsevier]

The role of straw bale as a construction material for reducing the whole-life impacts of housing is examined. The embodied and operational CO2 emissions in a recently completed UK social housing project are compared using alternative domestic external wall constructions and the effects on the resulting CO2 emissions. It is estimated that over 15 tonnes of CO2 may be stored in biotic materials of each of the semi-detached houses, of which around 6 tonnes are sequestered by straw and the remaining by wood and wood products. This suggests the carbon lock-up potential of renewable construction materials is capable of reducing the case study house's whole-life CO2 emissions of the house over its 60-year design life by 61% when compared with the case without sequestration. The practical implications of construction, detailing, maintenance, cost and self-build potentials of straw-bale construction are also considered. The potential for load-bearing straw-bale walls is examined through the whole-life performance of straw-bale construction with alternative conventional external walling systems. Le role de la balle de paille comme materiau de construction pour reduire l'impact des logements en termes de cycle de vie est examine. Les emissions de CO2 intrinseques et operationnelles dans un ensemble de logements sociaux recemment acheve au Royaume-Uni sont comparees, en utilisant des methodes differentes de construction des murs exterieurs des logements et les effets des emissions de CO2 qui en resultent. Il est estime qu'il est possible de stocker plus de 15 tonnes de CO2 dans les materiaux biotiques de chacun de ces pavillons jumeles, dont 6 tonnes environ sont sequestrees par la paille, le reste l'etant par le bois et les produits ligneux. Ceci suggere que les possibilites de sequestration du carbone offertes par les materiaux de construction renouvelables sont capables de reduire de 61 % les emissions de CO2 durant le cycle de vie des maisons de cette etude de cas, pour une duree de vie nominale des maisons de 60 ans, par comparaison avec le cas de figure sans sequestration. Sont egalement envisagees les implications pratiques des possibilites qu'offre une construction utilisant des balles de paille en termes de construction, de details de construction, d'entretien, de cout et d'autoconstruction. Le potentiel d'utilisation de balles de paille pour les murs porteurs est etudie sous l'angle des performances, tout au long du cycle de vie, de constructions en balles de paille faisant appel a differents systemes classiques de construction des murs exterieurs. Mots cles: emissions de CO2, cout, energie intrinseque, energie operationnelle, CO2 sequestre, logement social, balle de paille [ABSTRACT FROM AUTHOR]

[Display omitted] Urban built form and density are crucial parameters for the optimization of building energy performance. However, a cohesive framework which correlates building energy with urban built form and density is lacking, with no unified agreement on the concept of urban density. This study establishes the subtle interrelationships between urban built forms, density and building energy performance using two density indicators, specifically, site coverage and plot ratio. This paper initially considers geometrical variables of four customary urban built forms to investigate their relationship with the density indicators. Energy analyses are performed on the geometrical models representing residential buildings using the City of London as an example of a temperate climate. Annual building energy demands of pavilion, terrace, court and tunnel-court forms are calculated. The findings are used to produce a heat map of energy intensity on the Form Signature graphs. Results show that high-rise buildings with greater plan depths achieve higher energy efficiency. Moreover, it is shown that greater cut-off angles correspond to higher energy demands under temperate climatic conditions. An energy indicator, termed Energy Equity is introduced which represents the ratio between PV energy generation installed on roofs with respect to the total energy demand of the building. Further analyses show that by considering energy demand and PV energy generation simultaneously, low-rise buildings with greater plan depths provide improved energy performance. A comparative analysis of the energy performance of different built forms with similar geometric parameters demonstrates that the tunnel-court and the pavilion built forms provide the best and worst energy performance, respectively. However, when constraining density whilst changing other geometric parameters, this converse is true. Finally, the study illustrates that the same density for the same built form can be achieved by different combinations of geometric parameters that certainly affects energy performance of buildings. Graphic display of the analysis results provide urban planning guidelines that represent the database of major findings of this study. It can be used by designers, planners and architects to identify the most energy-efficient built form and density for promoting more sustainable cities. [ABSTRACT FROM AUTHOR]

Several studies have demonstrated the capability of data-driven modelling based on on-site measurements to characterise the thermal performance of building envelopes. Currently, such methods include steady-state and dynamic heating experiments and have mainly been applied to scale models and unoccupied test buildings. Nonetheless, it is proposed to upscale these concepts to characterise the thermal performance of in-use buildings based on on-board monitoring (OBM) devices which gather long-term operational data (e.g., room temperatures, gas and electricity consumption...). It remains, however, to be proven whether in-use data could be a cost-effective, practical and reliable alternative for the dedicated tests whose more intrusive measurements require on-site inspections. Furthermore, it is presently unclear what the optimal experimental design of the OBM would be and which data analysis methods would be adequate. This paper presents a first step in bridging this knowledge gap, by using on-board monitoring data to characterise the overall heat loss coefficient (HLC) [W/K] of an occupied, well-insulated single-family house in the UK. With the aid of a detailed building physical framework and specifically selected data subsets a sensitivity analysis is carried out to analyse the impact of the measurement set-up, the duration of the measurement campaign and the applied data analysis method. Although the exact HLC of the building is unknown and no absolute errors could hence be calculated, this paper provides a new understanding of the decisions that have to be made during the process from design of experiment to data analysis. It is demonstrated that such judgements can lead to differences in the mean HLC estimate of up to 89.5%. [ABSTRACT FROM AUTHOR]