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The processes of urbanisation and climate change are necessitating the transformation of cities towards sustainable cities that are robustly adapted to natural hazards, while simultaneously reducing energy and resource usage to mitigate further climatic change. Frequently such objectives conflict with each other, negatively affecting sustainability as a whole. For example, urban intensification with the intention of lowering transport energy costs has been found to exacerbate urban heat islands, increase flood risk and lead to poor health outcomes. This paper presents the use of an evolutionary computing spatial optimisation framework as one method by which multiple positively and negatively correlated sustainability objectives can be evaluated in time and space to assist urban planning. A coupled genetic algorithm and pareto optimisation approach is used to evaluate spatial configurations of future development against sustainability objectives (e.g., reduced heat risk, minimal flood risk, brown field development, optimal mobility). The developed approach is evaluated in a Greater London Authority (GLA) case study that simulates future urban development patterns that satisfy projected population growth whilst being sensitive to climate induced hazards and current planning policies. The spatial optimization framework developed significantly improves upon the existing urban development plan with the Pareto-front found to be 35% better than the proposed spatial plan for London. However, trade-offs between objectives were found to exist, most notably it was not possible to achieve a pairwise optimization between heat and flood risk and urban sprawl and heat risk. [ABSTRACT FROM AUTHOR]

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]

In this paper, driving strategy optimization for a track is proposed for an energy efficient battery electric vehicle dedicated to the Shell Eco-marathon. A measurement-based mathematical vehicle model was developed to simulate the behavior of the vehicle. The model contains complicated elements such as the vehicle's cornering resistance and the efficiency field of the entire powertrain. The validation of the model was presented by using the collected telemetry data from the 2019 Shell Eco-marathon competition in London (UK). The evaluation of applicable powertrains was carried out before the driving strategy optimization. The optimal acceleration curve for each investigated powertrain was defined. Using the proper powertrain is a crucial part of energy efficiency, as the drive has the most significant energy demand among all components. Two tracks with different characteristics were analyzed to show the efficiency of the proposed optimization method. The optimization results are compared to the reference method from the literature. The results of this study provide an applicable vehicle modelling methodology with efficient optimization framework, which demonstrates 5.5% improvement in energy consumption compared to the reference optimization theory. [ABSTRACT FROM AUTHOR]

Aviation emissions that are dispersed into the Earth's atmosphere affect the climate and air pollution, with significant spatiotemporal variation owing to heterogeneous aircraft activity. In this paper, we use historical flight trajectories derived from Automatic Dependent Surveillance–Broadcast (ADS-B) telemetry and reanalysis weather data for 2019–2021 to develop the Global Aviation emissions inventory based on ADS-B (GAIA). In 2019, 40.2 million flights collectively travelled 61 billion kilometres using 283 Tg of fuel, leading to CO2, NOX, non-volatile particulate matter (nvPM) mass and number emissions of 893 Tg, 4.49 Tg, 21.4 Gg, and 2.8×1026, respectively. Global responses to COVID-19 led to reductions in the annual flight distance flown, CO2, and NOX emissions in 2020 (-43 %, -48 % and -50 %, respectively relative to 2019) and 2021 (-31 %, -41 % and -43 %, respectively) with significant regional variability. Short-haul flights with duration < 3 h accounted for 83 % of all flights, yet only for 35 % of the 2019 CO2 emissions, while long-haul flights with duration > 6 h (5 % of all flights) were responsible for t43 % of CO2 and 49 % of NOX emissions. Globally, actual flight trajectories flown are, on average, ~5 % greater than the great-circle path between the origin-destination airport but this varies by region and flight distance. An evaluation of 8,705 unique flights between London and Singapore showed large variabilities in the flight trajectory profile, fuel consumption and emission indices. GAIA captures the spatiotemporal distribution of aviation activity and emissions and is provided for use in future studies to evaluate the negative externalities arising from global aviation. [ABSTRACT FROM AUTHOR]

Carbon emissions, being hazardous, are triggering social concerns which have led to the creation of international treaties to address climate change. Similarly, the United Kingdom under the Climate Change Act (2008) has committed to reducing its greenhouse gas emission by at least 80% over 1990 levels by 2050. However, being the oldest member of the EU states (before Brexit), the UK has the oldest housing stock, which contributes to 45% of its carbon emissions due to the older dwellings. To address this issue low carbon retrofitting is needed. Therefore, this paper seeks to investigate the barriers and enablers to energy efficiency retrofitting in social housing in London, UK based on the perception of experts employed in National and construction companies with an experience that ranges between 6 to 16 years. Initial literature suggested that the problem of energy efficiency retrofitting in the general building stock has been addressed, however little has been reported on its application to social housing. This paper, therefore, groups the barriers and enablers into seven categories that include: financial matters, Technical, IT, Government policy and regulation, social factors (including awareness of the energy efficiency agenda), quality of workmanship and disruption to residents, using literature review, interviews and surveys with key stakeholders within the housing sector, and draws recommendations to enable effective and efficient retrofitting for social housing projects. [ABSTRACT FROM AUTHOR]

British cities and residential suburbs were originally developed under a modernist growth logic: separating home from work, with little concern for energy use. But recent political and social priorities such as climate change and energy security have created an imperative to reduce domestic energy use, with many existing dwellings rendered "obsolete" on account of their poor energy efficiency. This precipitated a need to develop domestic retrofit – the modification of building fabrics and systems to improve their energy efficiency – as an urban infrastructure. The UK Government responded in 2011 with policies such as the "Green Deal", through which coalitions of actors in cities including local authorities, voluntary sector organisations and private businesses were encouraged to experiment with place-based retrofit. This paper examines the challenges and effects of developing a domestic retrofit infrastructure in a North London borough under particularly challenging policy conditions. We develop a hybrid framework for understanding the process and product of this place-based experimentation and through this we ask two questions: 1. How did both local and national conditions enable and limit the development of this infrastructure? 2. Was the emerging urban infrastructure functional and equitable? In Haringey's case, a strong local political agenda positioned retrofit as a development opportunity and vehicle for reducing inequality, but national priorities around market-making and technological fixes dominated emerging responses. Whilst Haringey's efforts in a difficult policy context did result in retrofits and improvements to around a thousand properties, the emerging infrastructure of retrofit services was incomplete, inequitable and temporary. [ABSTRACT FROM AUTHOR]

Microgeneration technologies offer the potential for distributed energy supply and consumption resulting in reduced reliance on centralised generation. Adoption of microgeneration for use in community settings is usually understood as having a beneficial contribution to sustainable development. This is particularly relevant in urban environments which present specific challenges relating to the heterogeneity of building and land use. Small-scale installations in buildings also appear to offer technological flexibility at the ‘human’ level, necessary for local participation in shaping the direction of sustainable development. This paper reports on a project concerned with identifying on-site energy generation projects in Greater London. A database was compiled comprising renewable and energy efficient microgeneration installations in multi-occupancy buildings. The relationships between each project and its associated organisations are mapped as a social network, which illustrates the heterogeneity of technologies and actors involved, as well as the flows of funding and expertise. The structure of the resulting networks indicates a lack of participation by social or not-for-profit groups who are traditionally identified as community level actors. The findings indicate that large institutional actors on the supply side may become regarded as renewable energy experts. Hence, there is a need to consider how the concept of community level actors in urban microgeneration projects is applicable to local government and commercial organisations. [ABSTRACT FROM AUTHOR]

Over the past decade, a growing body of research has examined the role of cities in addressing climate change and the institutional and political challenges which they encounter. For the most part, in these accounts, the infrastructure networks, their material fabric, everyday practices and political economies, have remained unexamined. In this paper, it is argued that this is a critical omission and an approach is developed for understanding how urban responses to climate change both configure and are configured by infrastructure networks. Central to any such analysis is the conception of how and why (urban) infrastructure networks undergo change. Focusing on urban energy networks and on the case of London, the paper argues for an analysis of the ‘urban infrastructure regimes’ and ‘experiments’ through which climate change is governed. It is found that climate change experiments serve as a means through which dominant actors articulate and test new ‘low-carbon’ logics for urban infrastructure development. It is argued that experiments work by establishing new circuits, configuring actors in new sets of relations and through these means realising the potential for addressing climate change in the city. At the same time, experiments become sites of conflict, a means through which new forms of urban circulation can be confined and marginalised, leaving dominant energy regimes (relatively) intact. [ABSTRACT FROM PUBLISHER]

The environmental impact of the UK building stock has increased the pressure on architects, engineers and building operators to reduce the use of air conditioning in favour of more passive cooling solutions. Good progress has been made in this direction but many passive solutions are limited to new-build projects. For existing buildings, and those for which mechanical air conditioning cannot be avoided, low energy cooling capability can be incorporated to improve significantly overall efficiency. This paper focuses on one such example – cooling using groundwater, which has gained popularity in recent years in the London area. Among the reasons for this are the excellent energy efficiency and the increasing viability of water abstraction systems. [ABSTRACT FROM AUTHOR]

The density of the domestic building stock of London is explored, moving from the scale of individual house and blocks of flats, through larger geographical units, to complete boroughs. The description of the stock is highly detailed and is made using the 3DStock method, which derives building geometry from digital maps and LiDAR (laser measurements from overflying aircraft). This means that accurate estimates of floor areas can be made and used to measure densities as Floor Space Index (FSI) values. Ground coverage or Ground Space Index (GSI) values are calculated from building footprints and land boundaries. The Spacemate tool, devised by Berghauser Pont and Haupt, is used to plot the types and ages of dwellings in terms of FSI, GSI and numbers of storeys. Figures for actual annual gas and electricity consumption are attached to each dwelling. Analysis shows that, in general, energy-use intensities--and especially the intensity of gas use for heating--decrease with increasing density, and with the transition between house types, from detached, to semi-detached, to terraces, to (low-rise) flats. [ABSTRACT FROM AUTHOR]

Heating and cooling in high-rise buildings devour about one-third of overall energy consumption. Skycourts is increasingly integrated in high-rise buildings, in particular offices. Skycourts are perceived as transitional and social nodes. This paper aims to investigate potentials of a skycourt when perform as a ventilated buffer zone in offices in a temperate climate. Using a hypothetical office building in London, a coupled approach of energy simulation and CFD was carried out for two ventilation modes; air-conditioned skycourt, and alternative models that incorporate combined ventilation strategies with the adjacent offices' zones of the skycourt. Furthermore, to determine the most critical ventilation conditions, different parameters were investigated. Overall, the results highlight that the incorporation of a ventilated skycourt potentially has a significant impact on the annual energy consumption. The optimized parameters enhance comfort temperature ranges of skycourts. Finally, the study developed guidelines to define the most effective configurations of ventilated skycourts. [ABSTRACT FROM AUTHOR]

Significant heat is generated by underground trains, particularly when braking, stopping at platforms and accelerating away from stations. A complex ventilation system including shaft, fans and under-platform extraction thus has to be designed to manage the rising temperature in tunnels and stations. This conventional approach results in high energy consumption for running the fans and neglects the possibility to use the extracted heat above ground in buildings. Lining underground rail tunnels with heat-exchange segments can provide an alternative solution to cool the tunnels and surrounding ground, and transfer the harvested heat to adjacent buildings for heating. It will also bring benefits in terms of reduction of energy consumption for tunnel ventilation operations. This paper reports on the work carried out in designing thermal energy segments for use on the tunnelled sections of the Crossrail project in London, UK. [ABSTRACT FROM AUTHOR]

With a changing climate, London is expected to experience more frequent periods of intense rainfall and tidal surges, leading to an increase in the risk of flooding. This paper describes the simulation of the drying of flooded building archetypes representative of the London building stock using the EnergyPlus-based hygrothermal tool ‘University College London-Heat and Moisture Transfer (UCL-HAMT)’ in order to determine the relative drying rates of different built forms and envelope designs. Three different internal drying scenarios, representative of conditions where no professional remediation equipment is used, are simulated. A mould model is used to predict the duration of mould growth risk following a flood on the internal surfaces of the different building types. Heating properties while keeping windows open dried dwellings fastest, while purpose built flats and buildings with insulated cavity walls were found to dry slowest. [ABSTRACT FROM PUBLISHER]

Abstract: In this paper an attempt has been made to assess the performance of an office building located in London (one of the case study buildings in CIBSE TM36: 2005) in relation to energy consumption, carbon emissions and potential for adaptability to the 2050s climate. Overheating is a particular issue in office buildings due to internal heat gains from computers and other electrical equipmen t. In addition, buildings in London are affected by the urban heat island, which is likely to intensify with warmer summer temperatures, reducing the capacity for night-time cooling of buildings. This paper proposes various passive design strategies which aim to address both mitigation (by reducing carbon emissions) and adaptation (by improving human comfort and reducing energy consumption). [Copyright &y& Elsevier]

Abstract: This paper presents the results of a computational study on the energy consumption and related CO2 emissions for heating and cooling of an office building within the Urban Heat Island of London, currently and in the future. The study developed twenty weather files in an East-West axis through London; the weather files were constructed according to future climate change scenario for 2050 suitable for the UK which have been modified to represent specific locations within the London UHI based on measurements and predictions from a program developed for this purpose (LSSAT). The study simulated an office with typical construction, heat gains and operational patterns with an advanced thermal simulation program (IESVE). The predictions confirm that heating load decreases, cooling load and overheating hours increase as the office location moves from rural to urban sites and from present to future years. It is shown that internal heat gains are an important factor affecting energy performance and that night cooling using natural ventilation will have a beneficial effect at rural and city locations. As overheating will increase in the future, more buildings will use cooling; it is shown that this might lead to a five-fold increase of CO2 emission for city centre offices in London in 2050. The paper presents detailed results of the typical office placed on the East-West axis of the city, arguing the necessity to consider using weather files based on climate projections and urban heat island for the design of current buildings to safeguard their efficiency in the future. [Copyright &y& Elsevier]

Decarbonization of marine transport is a key global issue, with the carbon emissions of international shipping projected to increase 23% to 1090 million tonnes by 2035 in comparison to 2015 levels. Optimization of the energy system (especially propulsion system) in these vessels is a complex multi-objective challenge involving economical maintenance, environmental metrics, and energy demand requirements. In this paper, data from instrumented vessels on the River Thames in London, which includes environmental emissions, power demands, journey patterns, and variance in operational patterns from the captain(s) and loading (passenger numbers), is integrated and analyzed through automatic, multi-objective global optimization to create an optimal hybrid propulsion configuration for a hybrid vessel. We propose and analyze a number of computational techniques, both for monitoring and remaining useful lifetime (RUL) estimation of individual energy assets, as well as modeling and optimization of energy use scenarios of a hybrid-powered vessel. Our multi-objective optimization relates to emissions, asset health, and power performance. We show that, irrespective of the battery packs used, our Relevance Vector Machine (RVM) algorithm is able to achieve over 92% accuracy in remaining useful life (RUL) predictions. A k-nearest neighbors algorithm (KNN) is proposed for prognostics of state of charge (SOC) of back-up lead-acid batteries. The classifier achieved an average of 95.5% accuracy in a three-fold cross validation. Utilizing operational data from the vessel, optimal autonomous propulsion strategies are modeled combining the use of battery and diesel engines. The experiment results show that 70% to 80% of fuel saving can be achieved when the diesel engine is operated up to 350 kW. Our methodology has demonstrated the feasibility of combination of artificial intelligence (AI) methods and real world data in decarbonization and optimization of green technologies for maritime propulsion. [ABSTRACT FROM AUTHOR]

Buildings are responsible for one‐third of the UK's greenhouse gas (GHG) emissions. The move to reduce emissions has resulted in recent stringent building regulations primarily aimed at reducing heating and associated energy use, often by improving the building fabric's airtightness. However, internal gains dominated, highly–insulated and airtight non‐domestic buildings will likely overheat in the projected warming climate, requiring energy‐intensive cooling, thus diminishing the effectiveness of heating efficiency focused regulations. This research investigated the effects of the warming climate on overheating and energy use and resulting emissions in representative urban office spaces in London in the present‐day and projected future climates using hourly dynamic thermal simulations. Findings suggest that airtight and highly–insulated office buildings in the temperate UK will overheat in the 2050s. Heating demand reduces by at least 36% in the 2050s but electricity consumption and summertime space conditioning will increase by at least 13% and 55% respectively when hybrid cooling is adopted to ameliorate overheating. Despite the increase, a mixed‐mode ventilation strategy is one of the ways of achieving overall energy efficiency while meeting benchmark overheating and emissions targets. Current heating‐focused legislation needs to be re‐evaluated to account for the effects of the warming climate and overheating risks. [ABSTRACT FROM AUTHOR]

Abstract: One of the primary reasons for the application of cool materials is their energy and associated environmental impact on the built environment. Cool materials are usually applied on the roof of buildings to reduce cooling energy demand. The relative benefits of this reduction depend on the construction of the building, external weather conditions and use of the building. This paper examines the impact from the application of a reflective paint on a flat roof in a naturally ventilated office building in the area of London, UK where the climate is moderate with high heating demand by buildings. The environmental conditions (internal/external air and surface temperatures) of the building were monitored before and after the application of the cool roof during the summer. It was found that internal temperatures were reduced after the application of the cool roof. The building was modelled using TRNSYS and the model was calibrated successfully using the measurements. A parametric analysis was carried out by varying the reflectivity and insulation of the roof and ventilation rate; the heating and cooling demand for a year was calculated using the Summer Design Year for London as the weather file. It was found that cooling demand is significantly reduced, heating demand is increased and the total energy savings vary between 1 and 8.5% relative to an albedo of 0.1 for the same conditions. In free floating (naturally ventilated) buildings summer comfort is improved but there is a penalty of increased heating energy during the winter. Thermal comfort can be improved by an average of 2.5°C (operative temperature difference for a change of 0.5 in albedo) but heating demand could be increased by 10% for a ventilation rate of 2 air changes per hour. The results indicate that in the case of temperate climates the type, operation and thermal characteristics of the building should be considered carefully to determine potential benefits of the application of cool roof technology. For the examined case-study, it was found that a roof reflectivity of 0.6–0.7 is the optimum value to achieve energy savings in a cooled office, improve summer internal thermal conditions in a non-cooled office (albeit with some heating energy penalty). It indicates that it is a suitable strategy for refurbishment of existing offices to improve energy efficiency or internal environmental conditions in the summer and should be considered in the design of new offices together with other passive energy efficient strategies. [Copyright &y& Elsevier]

• A novel energy-water ratio is developed for assessment of energy-water nexus. • A thermal model is developed to energy-water nexus. • The thermal model can be used to evaluate the value of energy-water nexus. • Different interdependence between energy-water at the building level are found. • The improved energy efficiency of boiler can save not only energy but also water. Energy and water are two critical resources, and their security has been becoming a regional, national and global priority. The paper investigates the energy-water nexus at the building level through developing a novel energy-water ratio and a thermal model, to provide insight about the interaction mechanism between energy and water at the building level. The developed energy-water ratio has clear physical meaning. The thermal model developed can be used to explore the dynamic interdependences and feedback mechanism between energy and water, and to evaluate the value of interdependence and the real value of infrastructure through linking to business model. The dynamic of energy-water nexus for three kinds of buildings in London is then examined under present and future climate scenarios. Results show that the interdependences of energy-water for these three kinds of buildings vary over time and are different each other. The different interdependences are shaped by the combined effect of both the configurations of infrastructures for building and the environmental condition. The improved energy efficiency of boiler can save not only energy but also water, indicating the positive interaction between energy and water. Results have informative implications for sustainable building and investment in household infrastructures, and suggest an integrated way for co-managing both energy and water effectively. [ABSTRACT FROM AUTHOR]

Urban water systems can be highly energy intensive. Yet, they are also excellent candidates for demand-response since they possess readily controllable operations and large amounts of storage. However, real-worlds trials have delivered mixed results, which implies the need to understand the underlying mechanisms of flexibility in water operations. This paper studies the potential to shift energy demand in an urban water system located in the River Thames basin, a region encompassing the city of London, England. Results show that the system could theoretically shift up to 20.1% of its annual energy demand for pumping (2.1 GWh), saving the local water utility around £5.6 million in electricity costs. However, the water system's flexibility is shown to be highly variable due to the variability in water demands and electricity prices, in-turn affecting the financial returns from demand-response. Sensitivity analysis reveals that factors such as the seasonal reservoir control strategies and total storage capacity are key determinants of system flexibility. A relationship between water storage capacity and flexibility is also derived, which could be used to estimate water sector flexibility in other regions. • Potential for demand-side response studied in London water supply system. • Dynamics in demands, prices and reservoir management are modelled. • Results showed substantial cost reduction as 2.5–20.1% of demand could be shifted. • Benefits of flexibility are volatile due to variability in water system. • Trade-offs between operational risk and flexibility are explored. [ABSTRACT FROM AUTHOR]

Metabolic energy consumption has long been thought to play a major role in the aging process (Pearl, The rate of living. University of London Press, London, 1928). Across species, a gram of tissue expends approximately the same amount of energy during the lifespan on average (Speakman, J Exp Biol 208:1717–1730, 2005). Energy restriction has also been shown to increase the maximum lifespan (McCay et al. J Nutr 10:63–79, 1935) and to retard age-associated changes (Weindruch and Walford, The retardation of aging and disease by dietary restriction. CC Thomas, Springfield, 1988). However, there are significant exceptions to universal energy consumption during the lifespan, mainly found by interclass comparison (Ramsey et al. Free Rad Biol Med 29:946–968, 2000; Atanasov, Trakia J Sci 10(3):1–14, 2012). Here, we present a universal relation that relates lifespan energy consumption to several physiological variables, such as body mass, temperature and the ratio of heart rate to respiratory rate, which have been shown to be valid for ∼ 300 species representing different classes of living organisms, from unicellular organisms to the largest mammals. This relation has an average scattered pattern restricted to factors of 2, with 95% ( 2 - σ ) of the organisms having departures of less than a factor of π from the relation, despite the difference of ∼ 20 orders of magnitude in body mass, reducing any possible interclass variation in the relation to only a geometrical factor. This result can be interpreted as supporting evidence for the existence of an approximately constant total number N r ∼ 10 8 of respiration cycles per lifetime for all organisms studied, effectively predetermining the extension of life through the basic energetics of respiration (quantified by t life = N r / f resp ); this is an incentive to conduct future studies on the relation of such a constant number N r of cycles per lifetime due to the production rates of free radicals and oxidants or alternative mechanisms, which may yield definite constraints on the origin of aging. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the key findings of a study conducted by London South Bank University for the Greater London Authority on the performance of the energy policies contained in the London Plan. These policies require developers to demonstrate how new developments within London will meet specific energy efficiency and renewable energy targets in order to gain planning permission. The study shows that 10% savings on CO2 emissions using renewable energy technologies were routinely met a year after the introduction of the policy. The study also shows that the largest CO2 savings are due to the use of combined heat and power. [Copyright &y& Elsevier]

Abstract: This paper identifies the vulnerabilities of operations at Heathrow airport to a short airport closure. The system disruptions assessed are delays, flight rerouting or diversions to alternate airports, and flight cancellations. In addition, the impact on fuel consumption, and hence CO2 emissions, is quantified using the Reorganized Air Traffic Control Mathematical Simulator Plus simulation model and the Advanced Emission Model tool. The results have implications for assessing how increased severe weather events associated with climate change may disrupt airport operations. [Copyright &y& Elsevier]

• Inclusion of multiple and diverse factors influencing domestic gas consumption. • Two-stage analysis to incorporate various geographical resolutions. • Different cluster algorithms to address different focus at each stage. • Provided localised domestic energy efficiency indicators for local authorities. Space heating with gas as the primary fuel is a dominant contributor of residential energy consumption in UK and hence important for achieving UK's 2050 carbon targets. Whilst most cities in the UK have reduced their emissions per capita, there is a large variation of domestic gas consumption within cities. Past research suggests that the variations in gas consumption are as much as function of the quality of built environment, as it is of wider socio-economic-demographic features of households. Their combined influence on variations of residential heating consumption is however not well understood. This paper proposes a novel two-layer clustering framework to address this gap. The proposed framework constitutes of Gaussian Mixture Models and Hierarchical clustering and is illustrated through the analysis of residential gas consumption across London. Results show eight clusters of London Lower Super Output Areas (LSOAs) explained along 18 dimensions that include built-environment, social-economic and demographic information. These 8 clusters are used as variables to further cluster four groups of local authorities. The distinct gas consumption related properties of the resulting clusters explain the sources of variations in gas consumption across clusters and indicate possible directions for future fine-tuning of local policies. [ABSTRACT FROM AUTHOR]

The article focuses on underground transportation in London, England. Climate change will have serious implications for the underground. Very hot weather increases the likelihood of rails buckling in the heat and hotter conditions for passengers. To address the effects of future climate change, London Underground Ltd. (LUL) has been working with the Greater London Authority on a project to examine the effects of climate change on the London transport network. LUL is also working with the University of Newcastle-upon-Tyne on a study into the effects of climate change on embankments and earth structures. LUL is also committed to waste minimization. Energy needs will continue to rise as the renewal of the underground system progresses, but LUL is taking steps to reduce consumption wherever possible and to purchase more electricity from renewable sources.

Minimization of the costs with simultaneous increase in the raw materials and energy use efficiency is a challenge for the modern world. One of the most effective tools to solve this task is the use of process intensification (PI), first proposed by Ramshaw C. The incentive for process intensification, Proceedings, 1st Intl. Conf. Proc. Intensif. for Chem. Ind., 18, BHR Group, London, 1995, p. 1. and then extended by Stankiewicz AI, Moulijn JA. Process intensification: transforming chemical engineering. Chem Eng Prog 2000: 22–34. In the presented review, some principles of PI in chemical engineering and their application for wide variety of processes is discussed. The role of the Russian scientist with a research background is carried out in other countries. [ABSTRACT FROM AUTHOR]

Specific combinations of energy flows, material flows and stocks are responsible for those services that support societal function and development. In this paper, we develop the concept and accounting method for material services, which we define as "those functions that materials contribute to personal or societal activity with the purpose of obtaining or facilitating desired end goals or states, regardless of whether or not a material flow or stock is supplied by the market". In this respect, material services are an intermediate step that incorporates stock to bridge the gap between resource consumption, accumulation and aspects of wellbeing. We provide a material service case study, which identifies the level of lighting experienced by urban Ancient Romans relative to that enjoyed by inhabitants of 1820s London (the Georgians). Our results show that the average Roman experienced 41,102 lm-hour/year, which is more lighting than the Georgian value per capita (at 35,698 lm-hour/year). In terms of fuel consumption, Georgians were four times more efficient than their Roman counterparts, but there was a trade-off between materials and energy, given that stock efficiency was 53 times lower than that of the Romans. This trend of improving fuel efficiency at the expense of materials appears to have continued into the 21st century, which holds important implications for sustainable development. Further research needs to be undertaken to ascertain whether this holds true for other material services such as heating, transport and shelter. [ABSTRACT FROM AUTHOR]

A strong correlation exists between occupant behaviour and space heating energy use. In particular, the occupancy status (e.g., daytime absence) is known to have a significant influence on residential heating load profiles, as well as on cumulative heating energy consumption. In the literature, many occupancy models have been utilised to predict occupancy profiles of individual dwellings as part of the larger residential building stock. However, none of the existing models consider diversity associated with occupancy-integrated archetypes to generate high-temporal resolution heating load profiles. The current paper uses Time Use Survey (TUS) data to develop a high-temporal resolution residential building occupancy model. The key feature of the proposed model, implemented using MATLAB, is the ability to generate stochastic occupancy time-series data for national population subgroups characterised by specific occupancy profiles. It is shown that the results are capable of closely approximating data available from TUS. The developed model can be applied to improve the quality of modelled high-temporal resolution heating load profiles for generic building stock characterised by population subgroups represented by different occupancy-integrated archetypes. A case study is performed on a building stock sample located in London, UK. The developed occupancy model has been implemented in MATLAB and is available for download. [ABSTRACT FROM AUTHOR]

A warming climate, increasing frequency and severity of extreme heat events, and the heat island effect are cumulatively expected to exacerbate climate thermal loading on urban buildings. This in turn could lead to increased summertime overheating risk, with any active means for addressing this likely to influence future energy consumption and CO 2 emission patterns. This paper examines how the microclimatic loading presented by the heat island (UHI) effect influences summertime adaptive comfort in traditional urban residential buildings. The method for addressing this utilises the novel approach of coupling a computationally efficient urban climate model with an established building energy model to simulate a residential street canyon within the London heat island. Key findings highlighted adaptive capabilities to achieve summertime 'comfort' in most rooms without the need for energy intensive mechanical cooling. The alternative of using indiscriminate and widespread mechanical cooling within the canyon length is estimated to result in a 0.4 K increase in nocturnal canyon temperatures, and an additional 4.4% of CO 2 released to the climate. In contrast, a targeted approach of cooling rooms where adaptive capacity is insufficient more than halves the canyon CO 2 emission estimate; which in turn highlights the necessity for detailed overheating assessments in managing energy use in such traditional residential neighbourhoods within UHIs. [ABSTRACT FROM AUTHOR]

Overheating in buildings is one of the increasing concerns related to climate change and can lead to an increase in heat-related health issues and higher energy consumption due to the use of air conditioning systems. Literature shows that internal conditions and demand on environmental control systems can vary with height within buildings. However, an architectural trend towards highly glazed façades for tall buildings suggests the vertical gradient of performance is not always considered in the design process. By simulating a high-rise residential building in London, a comparative analysis of the overheating risks and daylighting at different levels in the building was conducted. In this study the model was able to consider the influence of surrounding built environment on solar gain and so influence of urban location on overheating risk was taken into account. Simulations were conducted using typical reference years as well as meteorological data for specific heat-wave periods experienced in London and that are expected to become more intense and frequent due to climate change. Passive mitigation options (external shading) are demonstrated to help reduce overheating occurrence by 74%, at the same time the impact of decreased daylighting (30%) is less problematic at higher levels where daylight factor is greater. [ABSTRACT FROM AUTHOR]

Urban metabolism is an important technique for understanding the relationship between cities and the wider environment. Such analyses are typically performed at the scale of the whole city using annual average data, a feature that is driven largely by restrictions in data availability. However, in order to assess the resource implications of policy interventions and to design and operate efficient urban infrastructures such as energy systems, greater spatial and temporal resolutions are required in the underlying resource demand data. As this information is rarely available, we propose that these demand profiles might be simulated using activity-based modeling. This is a microsimulation approach that calculates the activity schedules of individuals within the city and then converts this information into resource demands. The method is demonstrated by simulating electricity and natural gas demands in London and by examining how these nontransport energy demands might change in response to a shift in commuting patterns, for example, in response to a congestion charge or similar policy. The article concludes by discussing the strengths and weaknesses of the approach, as well as highlighting future research directions. Key challenges include the simulation of in-home activities, assessing the transferability of the complex data sets and models supporting such analyses, and determining which aspects of urban metabolism would benefit most from this technique. [ABSTRACT FROM AUTHOR]

The urban heat island (UHI) is a well-known effect of urbanisation and is particularly important in world megacities. Overheating in such cities is expected to be exacerbated in the future as a result of further urban growth and climate change. Demonstrating and quantifying the impact of individual design interventions on the UHI is currently difficult using available software tools. The tools developed in the LUCID (‘The Development of a Local Urban Climate Model and its Application to the Intelligent Design of Cities’) research project will enable the related impacts to be better understood, quantified and addressed. This article summarises the relevant literature and reports on the ongoing work of the project.Practical applications: There is a complex relationship between built form, urban processes, local temperature, comfort, energy use and health. The UHI effect is significant and there is a growing recognition of this issue. Developers and planners are seeking advice on design decisions at a variety of scales based on scientifically robust, quantitative methods. The LUCID project has thus developed a series of tools that (1) quantify the effect of urbanisation processes on local environmental conditions, and (2) quantify the impact of such conditions on comfort, energy use and health. The use of such tools is vital, both to inform policy but also to be able to demonstrate compliance with it. [ABSTRACT FROM PUBLISHER]

A conceptual framework and methodological approach are developed to understand the potential linkage between urban domestic heat demand and the heatwave vulnerability index, using the London building stock as a case study. A geographic information system (GIS)-based systematic approach towards exploring the impact of the urban built form and the heat island phenomenon on domestic space heating needs and heat-related mortality is demonstrated. The physical properties of individual dwellings were inferred from existing GIS databases as a function of given attributes (such as the form and age of the property). Localized annual heating degree-days (HDD) across London were predicted using a site-specific model. Each dwelling was modelled using a modified version of the steady-state annual domestic energy model. The energy consumption profiles generated were subsequently compared with existing top-down regional energy statistics. In addition, local environmental factors such as built density, green coverage ratio, and land surface temperature were extracted from a combination of GIS and satellite image data sources. By mapping these factors across the Greater London Area, their influence on the risk of heat death during the 2006 heatwave was examined. The model could potentially be utilized to inform urban-scale policies relating to the reduction of CO2 emissions and the identification of heat-vulnerable population groups across London. Un cadre conceptuel et une approche methodologique sont developpes afin de comprendre le lien potentiel entre la demande urbaine en chauffage domestique et l'indice de vulnerabilite aux vagues de chaleur, en utilisant le parc bati de Londres comme etude de cas. La demonstration est faite d'une approche systematique basee sur des systemes d'information geographique (SIG) visant a explorer l'impact de la forme batie urbaine et du phenomene de l'ilot de chaleur sur les besoins en chauffage de l'espace domestique et la mortalite liee a la chaleur. Les proprietes physiques des logements individuels ont ete deduites des bases de donnees SIG existantes utilisees comme une fonction d'attributs donnees (tels que la forme et l'age des biens immobiliers). La prevision des degres-jours de chauffage (DJC) annuels localises sur Londres s'est faite en utilisant un modele specifique au site. Chaque logement a ete modelise en utilisant une version modifiee du modele d'energie domestique annuelle en regime continu. Les profils de consommation d'energie generes ont ete compares ulterieurement aux statistiques energetiques regionales descendantes existantes. De plus, les facteurs environnementaux locaux tels que la densite du bati, le coefficient d'espaces verts et la temperature superficielle des terres ont ete extraits d'une combinaison de sources de donnees provenant de SIG et d'images satellite. En dressant des cartes de ces facteurs sur la Region du Grand Londres, leur influence sur le risque de mortalite par la chaleur pendant la vague de chaleur de 2006 a ete examinee. Ce modele pourrait potentiellement etre utilise pour influencer les politiques a l'echelle urbaine qui sont liees a la reduction des emissions de CO2 et a l'identification des groupes de populations vulnerables a la chaleur sur Londres. Mots cles: parc bati, changement climatique, parc de logements, consommation d'energie, systeme d'information geographique (SIG), demande de chaleur, mortalite liee a la chaleur, surchauffe, planification durable, ilot de chaleur urbaine [ABSTRACT FROM AUTHOR]

Biofuels as alternative fuels in today's world are becoming increasingly important for the reduction of greenhouse gases. Here, we present and evaluate the potential of a new alternative fuel based on the conversion of medium-chain fatty acids to biojet (MBJ), which was produced from coconut oil using hydrotreated processes. MBJ is produced by using both deoxygenation and isomerization processes. Several blends of this type of biojet fuel with Jet A-1 were run in a gas-turbine engine (Rover 1S/60, ROTAX LTD., London, England) for the purpose of investigating engine performance and emissions. Performance results showed almost the same results as those of Jet A-1 fuel for these fuels in terms of thermal efficiency, brake-specific fuel consumption, turbine-inlet temperature, and exhaust-gas temperature. The results of exhaust-gas emissions also showed no significant effects on carbon monoxide, unburned hydrocarbon, and nitrogen oxides, while a decrease in smoke opacity was found when blending MBJ with Jet A-1. MBJ performed well in both performance and emissions tests when run in this engine. Thus, MBJ brings hope for the development of aviation biofuels in tropical regions that have an abundance of bioresources, but are limited in technology and investment capital. [ABSTRACT FROM AUTHOR]