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As regulatory constraints limit energy communities' (ECs) participation in wholesale markets, these might rely on retailers' supply when local generation falls short. As balancing responsible parties, retailers are financially responsible for matching the volumes traded in the market with customers' actual needs. However, inadequate information about ECs' operations may complicate this task. This paper explores the interactions and financial implications for retailers under contractual agreements with ECs. We design a novel modelling framework, consisting of: (1) a stochastic model of a strategic retailer participating in the day ahead market considering imbalance costs, (2) a community model optimising its operations based on the agreed tariff subscription with the retailer, and (3) a simulation of the imbalance settlement process. The frameworks' applicability is demonstrated via a case study in London (UK). Results indicate that retailers' primary source of profit loss arises from the increased self-sufficiency of customers belonging to EC. On the other hand, deviations from the market commitments exerts limited effects on retailers financial outcomes. This is explained by the earnings obtained by providing passive balancing services to system operators. Also, the paper underscores retailers' need to reassess their business models, looking beyond merely establishing operational data exchange with ECs. • A unique modelling framework representing retailers and Energy Communities (ECs) interactions. • EC increase in self-sufficiency is the main driver for retailers' loss of profits. • The single imbalance price mechanism reduces retailers' loss of profits. • Retailers' information on EC operations does not lead to substantial cost savings. • Retailers might rethink their business strategies with ECs to keep their profit level. [ABSTRACT FROM AUTHOR]

This paper estimates the negative effects of motorised road traffic on the travel and walking behaviour of local residents in Great Britain and the cost of the wider negative impacts on local economic activity, external effects of motorised transport, social exclusion, neighbourhood social capital, self-rated health, and subjective wellbeing. We use the results of a survey (n = 3038) and models linking the characteristics of roads and pedestrian crossing facilities in each participant's local area, travel and walking behaviour, and the level and monetary value of the wider impacts of travel behaviour. The costs of road traffic borne by local communities were estimated as £31.9 billion per year, i.e. 1.6% of the Gross Domestic Product, or £631 per person. This value varies within the interval £569-£698/person/year, depending on the assumptions made. The highest estimated costs of motorised road traffic are reduced neighbourhood social capital (£236) and reduced subjective wellbeing (£196/person/year). The costs for some population segments, such as London residents, city residents, and people aged 25–34 are higher than the average. The characteristic of roads causing the highest costs is volume of motorised traffic above low (£264/person/year), followed by multiple lanes (£148), traffic speeds above low (£119), and absence of a median strip (£60). By quantifying for the first time, at the national level, the costs of the negative community effects of motor vehicles, this study provides evidence supporting policies to reduce traffic volumes and speeds and reallocate roadspace to pedestrians. [ABSTRACT FROM AUTHOR]

This paper uses a large UK cohort to investigate the impact of early-life pollution exposure on individuals' human capital and health outcomes in older age. We compare individuals who were exposed to the London smog in December 1952 whilst in utero or in infancy to those born after the smog and those born at the same time but in unaffected areas. We find that those exposed to the smog have substantially lower fluid intelligence and worse respiratory health, with some evidence of a reduction in years of schooling. [ABSTRACT FROM AUTHOR]

Abstract: This paper analyses changes in accessibility that might result from a new High-Speed Rail (HSR) line in the UK. A proposal for such a line put forward by Network Rail in 2009 is used as the basis for the analysis. Using travel time to London as the main benchmark to measure accessibility of a station on the current (conventional) and future (high-speed) rail networks the paper examines the likely winners and losers from the construction of the new line. The results show that the accessibility benefits from the proposed line are relatively limited in terms of geographic spread and that many cities close to it would not see any travel time reductions on journeys to London, thus will not see any accessibility benefits in this respect. For such places, this will translate to a relative reduction in the accessibility to London, when compared to other locations, and thus to potentially adverse socioeconomic implications. The paper concludes by arguing that any examination of a HSR line must consider a wider geographic area than just the cities, and especially the stations, on the line and it therefore must give due consideration to integration between transport networks, and especially between the high-speed and conventional rail networks. Based on the current analysis, the paper concludes that the case for a HSR line in the UK from a regional accessibility perspective is questionable. [Copyright &y& Elsevier]

Abstract Urban areas face a conundrum, they need to reduce their greenhouse gas emissions and consumption of resources, whilst also increasing their resilience to climate change and extreme weather, and improving wellbeing. However, it is widely recognized that well intended intervention to address one of these sustainability objectives in isolation can undermine other objectives. This paper presents a framework to efficiently identify spatial development strategies that provide the best outcomes against multiple objectives. The framework has been applied to London (UK) to identify strategies that can simultaneously: (i) minimize exposure to future heat wave events; (ii) minimize the risk from flood events; (iii) minimize transport emissions; (iv) minimize urban sprawl; (v) maximize brownfield development; and, (vi) prevent development of greenspace that is recognized as important to wellbeing. Prioritizing each objective in isolation leads to considerably different spatial planning structures, exposing conflicts between many objectives. These include tradeoffs between urban heat risk and transport emissions; and also previously undocumented conflicts between minimizing flood and heat risks. Allowing greater flexibility in development density is shown to provide benefits in terms of heat risk reduction, whilst not significantly affecting mitigation objectives. The framework is shown to significantly improve upon the London Spatial Development Strategy for the objectives analyzed. Further analysis identifies optimal spatial strategies to achieve a Low Carbon, Low Risk or Low Density city - however, these cannot be simultaneously maximized. This work shows there are difficult, and often irreconcilable, choices to be made in the spatial planning of sustainable cities. Spatial search and optimization tools strengthen the evidence-base for planning. Rapid identification of development strategies that satisfy, and minimize conflicts between, multiple objectives helps planners to develop strategies that simultaneously improve urban sustainability and reduce the risks from natural hazards. Highlights • Cities must reduce climate risks and greenhouse gas emissions, and improve wellbeing. • A spatial optimization framework has been developed and applied to London, U.K. • It is possible to optimize development for individual objectives. • There are tradeoffs between low risk, low carbon, low living density priorities. • Changing development density can have significant benefits for heat risk reduction. [ABSTRACT FROM AUTHOR]

Although district heat network schemes provide a pragmatic solution for reducing the environmental impact of urban energy systems, there are additional benefits that could arise from servicing electric vehicles. Using the electricity generated on-site to power electric vehicles can make district heating networks more economically feasible, while also increasing environmental benefits. This paper explores the potential integration of electric vehicle charging into large-scale district heating networks with the aim of increasing the value of the generated electricity and thereby improving the financial feasibility of such systems. A modelling approach is presented composed of a diverse range of distributed technologies that considers residential and commercial electric vehicle charging demands via agent-based modelling. An existing district heating network system in London was taken as a case study. The energy system was modelled as a mixed integer linear program and optimised for either profit maximisation or carbon dioxide emissions minimisation. Commercial electric vehicles provided the best alternative to increase revenue streams by about 11% against the current system configuration with emissions effectively unchanged. The research indicates that district heating network systems need to carefully analyse opportunities for transport electrification in order to improve the integration, and sustainability, of urban energy systems. • Framing of a modern district energy system as a mixed integer linear program. • Agent-based modelling used to simulate electric vehicle charging demands. • Electric vehicle charging in a district heating network simulated for a London area. • District heating integration with electric vehicles improves revenues by 11%. [ABSTRACT FROM AUTHOR]

• A micro-CHP system integrating PVT collectors, a SE and energy storage is considered. • A transient model is developed to evaluate technoeconomic and environmental performance. • The primary energy savings and carbon emission reduction amount to 35% and 37%. • The discounted payback period of the system is 28 years. • The system has greater environmental benefits and a longer payback period than alternatives. This paper presents a comprehensive analysis of the energetic, economic and environmental performance of a micro-combined heat and power (CHP) system that comprises 29.5 m2 of hybrid photovoltaic-thermal (PVT) collectors, a 1-kW e Stirling engine (SE) and energy storage. First, a model for the solar micro-CHP system, which includes a validated transient model for the SE micro-CHP unit, is developed. Parametric analyses are performed throughout a year to evaluate the effects of key component sizes and operating parameters, including collector flow rate, storage tank size, SE micro-CHP flow rate, and battery capacity, on the energetic, economic and environmental performance of the proposed system using real hourly weather data, and thermal and electrical energy demand profiles of a detached house located in London (UK). The optimum component sizes and operating parameters are determined accordingly. The daily and monthly operating characteristics of the system are evaluated, and its annual performance is compared to those of a reference system (gas boiler plus grid electricity), as well as of other alternative solar-CHP systems including a PVT-assisted heat pump system and a standalone PVT system. The results indicate that the installation of such a system can achieve an annual electricity self-sufficiency of 87% and an annual thermal energy demand coverage of 99%, along with annual primary energy savings and carbon emission reduction rate of 35% and 37% relative to the reference system. Over 30 years of operation, the net present value (NPV) of the proposed system is £1990 and the discounted payback period is 28 years. The economics of the proposed system is very sensitive to utility prices, especially the electricity purchase price. Relative to the alternative solar systems, the proposed system offers greater environmental benefits but has a longer payback period. This implies that although the energy saving and emission reduction potential of the proposed system is significant, the initial/capital investment, especially of the SE CHP unit and the PVT collector array, are currently high, so efforts should focus on the cost reduction of these technologies. [ABSTRACT FROM AUTHOR]

In the drive to contain urban sprawl and the desire to promote sustainable urban development that enhances the quality of inner city life, urban regeneration in London and in other major cities of the United Kingdom (UK) is facing ever more stringent scrutiny by planning authorities. With increasing emphasis on recreational use of outdoor areas in the vicinity of major urban new-build developments, designers and developers are facing up to the need to shape the external wind microclimate to ensure suitability for future use of open spaces and to deliver a low impact on public areas within the vicinity of the site. In the UK, tall buildings are drawing the attention of planning authorities like no other type of development due to their potential to cause downdrafts of fast upper-level winds, strong flow accelerations around building corners and funneling between neighbors. Planners expect to see due consideration from an early stage, not only via a comprehensive and robust wind assessment but also by demonstrating inbuilt design measures that offset or even prevent unacceptable impacts within an existing ‘present-day’ context plus, importantly, within a future context where other equally tall structures are expected to emerge. This technical paper will document the challenges of the planning process for wind assessment of tall buildings in the UK and in particular discuss the requirements of Environmental Impact Assessments (EIA) and the intricacies of wind engineering approaches that support this process. [ABSTRACT FROM AUTHOR]

• Data-driven and comprehensive thermodynamic technology models are developed. • Multi-fidelity approaches are used to compare heat-generation solutions. • Centralised CHP systems appear to be the most profitable option at present. • Heat pumps can achieve a significant degree of heat decarbonisation (55–62%). • Thermodynamic models reduce uncertainty by 75% compared to black-box approaches. This paper presents a multi-scale framework for the design and comparison of centralised and distributed heat generation solutions. An extensive analysis of commercially available products on the UK market is conducted to gather information on the performance and cost of a range of gas-fired combined heat and power (CHP) systems, air-source heat pumps (ASHPs) and ground-source heat pumps (GSHPs). Data-driven models with associated uncertainty bounds are derived from the collected data, which capture cost and performance variations with scale (i.e. , size and rating) and operating conditions. In addition, a comprehensive thermoeconomic (thermodynamic and component-costing) heat pump model, validated against manufacturer data, is developed to capture design-related performance and cost variations, thus reducing technology-related model uncertainties. The novelty of this paper lies in the use of multi-fidelity approaches for the comparison of the economic and environmental potential of important heat-generation solutions: (i) centralised gas-fired CHP systems associated with district heating network; (ii) gas-fired CHP systems or GSHPs providing heat to differentiated energy communities; and (iii) small-scale micro-CHP systems, ASHPs or GSHPs, installed at the household level. The pathways are evaluated for the case of the Isle of Dogs district in London, UK. A centralised CHP system appears as the most profitable option, achieving annual savings of £13 M compared to the use of decentralised boilers and a levelised cost of heat equal to 31 £/MWh th. However, if the carbon intensity of the electrical grid continues to reduce at current rates, CHP systems will only provide minimal carbon savings compared to boilers (<6%), with heat pumps achieving significant heat decarbonisation (55–62%). Differentiating between high- and low-performance and cost heat pump designs shows that the former, although 25% more expensive, have significantly lower annualised costs (£4.9 M vs. £7.7 M) and 12% higher CO 2 -equivalent savings. The uncertainty propagation reveals that data-driven and detailed thermoeconomic models can reduce the uncertainty in the total annualised energy cost and emissions by more than 75% compared to simplified black-box approaches, while the economic comparison of centralised CHP systems and domestic heat pumps for various electricity and gas price scenarios provides guidance to support energy policy. [ABSTRACT FROM AUTHOR]

• Tunnel construction works to calibrate 3D FE models of impact on heritage buildings. • Semi-coupled approach for modelling tunnel-building interaction during excavation. • A crack in the masonry façade was modelled as a discontinuity in equivalent solid. • Numerical models used to control construction works in conjunction with monitoring. • Advanced numerical modelling improves methodology to design and build urban tunnels. Controlling building displacements induced by tunnelling is a major issue in densely urbanised areas, particularly for listed heritage structures. Major tunnelling projects provide opportunities to assess the ability of advanced numerical models to address this issue, in conjunction with the large amount of monitoring data that are gathered during the works. This paper considers the case of two Grade-I listed buildings (St. Mary Abchurch and Mansion House) affected by the Bank Station Capacity Upgrade in London (UK) where complex excavation works were conducted to improve the existing underground infrastructure. Both conventional and innovative monitoring was carried out to control the effect of tunnel construction on these buildings. Following the works, three-dimensional finite element analyses were conducted by adopting a semi-coupled modelling approach. In these analyses, the pre-existing damage in the buildings prior to tunnelling has been considered by adjusting the properties of embedded solids that are used to idealise the structure. The analyses also considered salient aspects that are often neglected in routine risk-assessment procedures, such as the excavation modelling sequence covering both pilot tunnelling and enlargement, the skew building-tunnel alignment, and the effect of closely spaced tunnel excavations on surface ground deformations. The results highlight the challenges associated with idealising historic structures with semi-coupled models; nevertheless, they encourage the integrated use of innovative monitoring systems and advanced numerical modelling as a tool to control the process of tunnel excavation in complex urban environments. [ABSTRACT FROM AUTHOR]

The provision of subsidised workspace for small enterprises has been a public sector concern in many developed economies since the 1960s. In recent years, the focus of economic development initiatives has shifted away from supply side initiatives, such as fiscal incentives and the direct provision of premises, towards a consideration of the collective provision of infrastructure and services, in order to meet demands of businesses and workers in cities where there is already strong demand and growth. As well as this shift from supply- to demand-side initiatives, there has been a change in the political ideological approach to land and property development, away from public sector direct provision and funding, to place greater onus on the private sector to deliver development, infrastructure and services. The introduction of ‘affordable workspace’ planning policies by local authorities in London from the early 2000s is part of this shift – building on more established key worker and affordable housing policies. This paper evaluates the success of affordable workspace planning policies in thirteen mixed use schemes in London, from the perspectives of developers and workspace providers, who are responsible for delivering and managing the affordable workspace. First, it finds that the perspective of the developer, in particular whether it sees affordable workspace policy as (a) an opportunity, (b) a ‘tool’ to secure planning permission or (c) a burden, is mostly influenced by the way in which the affordable workspace emerged within the proposal. Developers’ perspectives and the success of their partnerships with workspace providers are critical to the successful delivery of affordable workspace within the scheme. Second, the findings show that ‘affordable workspace’ is difficult to define and deliver, with different interpretations used by delivery partners and the ability of workspace providers to deliver affordability depends critically on their organisational model. Finally, the research shows that although there are clear benefits of the policy for artists and small, creative industry businesses, it is not benefiting low-value manufacturers or small family-run retail and service businesses, nor is it generally benefiting start-ups. The implications of policy outcomes for economic development are considered; overall the beneficial impacts are limited. The research concludes that the predominant model of affordable workspace policy being promoted in London will fail to meet the aspirations of policy makers, with the limited success of policy further compounded by the global recession of the late-2000s. Alternative or complementary strategies are discussed. [ABSTRACT FROM AUTHOR]

It has been claimed that high social capital contributes to both positive public health outcomes and to climate change adaptation. Strong social networks have been said to support individuals and collective initiatives of adaptation and enhance resilience. As a result, there is an expectation that social capital could reduce vulnerability to risks from the impacts of climate change in the health sector. This paper examines evidence on the role social networks play in individuals’ responses to heat wave risk in a case study in the UK. Based on interviews with independently living elderly people and their primary social contacts in London and Norwich, we suggest that strong bonding networks could potentially exacerbate rather than reduce the vulnerability of elderly people to the effects of heat waves. Most respondents interviewed did not feel that heat waves posed a significant risk to them personally, and most said that they would be able to cope with hot weather. Bonding networks could perpetuate rather than challenge these narratives and therefore contribute to vulnerability rather than ameliorating it. These results suggest a complex rather than uniformly positive relationship between social capital, health and adaptation to climate change. [Copyright &y& Elsevier]

Abstract: This paper presents a comparison of the characteristics of the electricity demand for London, UK and Athens, Greece and explores its relationship with both climate and non-climate related factors. Year-to-year trends for both cities are identified, associated mainly with economic, social and demographic factors. In addition, several other effects such as weekly and holiday effects, unrelated to weather conditions are detected and are examined in comparison for the two cities. Gross National Product (GNP) per capita has been employed to aid de-trend the data in order to isolate the weather/climate influence on electricity demand. Temperature has been found to play the most important role in controlling the electricity load demand, especially for Athens. For both cities electricity demand peaks in winter but for Athens a second significant peak is apparent in the summer, not present in London. Thermal comfort levels for both cities have also been identified and compared. The optimum ambient temperature for low levels of electricity demand is found to be 20°C for Athens and 16°C for London. Using the approach of cooling and heating degree-days, it was identified that the sensitivity of the system electricity-demand/air-temperature is greater during the cold period of the year for both cities. [Copyright &y& Elsevier]

This paper considers the relationship between city-size and growth in a UK context. This has a number of elements. Using population data from 62 cities with an extended Turok and Mykhnenko (2007) classification of time paths, aligned ranks of population shares reveals that persistent advantageous or disadvantageous trends are in the majority. These persistent paths are at odds with the proposition that Zipf's law for cities is perpetuated by shocks being randomly distributed across the size spectrum. Three contributions in the field of convergence that can be applied here are: intra-distributional mobility; convergence, where there are persistent trends, implies eventual leapfrogging and divergence; which is explored by Boyle and McCarthy's (1997) concordance-based tests for beta-convergence. As population growth is found to be inversely related to city-prominence, there is evidence for convergence, but only in part. There is a U -shape in the size-growth relationship that is obscured by a decline in prominence among the very large cities whilst the primate city, London, is pulling away from the rest of UK urban system. It is argued that 'path-dependency' that reflects the inheritance of deindustrialisation is more appropriate than a Gibrat-type stochastic model of growth for the north and west. • A majority of cities are continuously declining or growing in prominence, implying a persistent cause. • With the notable exception of London, large centres are declining in prominence. • Movement down the size hierarchy more common than movement up but the latter is more rapid than the former. • There is prominence-convergence among the smaller cities. • There is a U -shape in the size-growth relationship, obscured by a decline in prominence among very large cities. [ABSTRACT FROM AUTHOR]

• 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]