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Editor's Choice Articles

Editor’s Choice articles are based on recommendations by the scientific editors of MDPI journals from around the world. Editors select a small number of articles recently published in the journal that they believe will be particularly interesting to authors, or important in this field. The aim is to provide a snapshot of some of the most exciting work published in the various research areas of the journal.

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Editorial

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Editorial
Collaboration, Adaptation, and Scaling: Perspectives on Environmental Governance for Sustainability
Sustainability 2018, 10(3), 679; https://0-doi-org.brum.beds.ac.uk/10.3390/su10030679 - 02 Mar 2018
Cited by 20
Abstract
In preview of the special issue on “Environmental Governance for Sustainability”, this manuscript examines three key themes on governance and sustainability. Governance for sustainability, by its nature, requires long-enduring institutional arrangements. Given the complex adaptive systems in which governance decision-making takes place, we [...] Read more.
In preview of the special issue on “Environmental Governance for Sustainability”, this manuscript examines three key themes on governance and sustainability. Governance for sustainability, by its nature, requires long-enduring institutional arrangements. Given the complex adaptive systems in which governance decision-making takes place, we explore three key characteristics of successful, long-term governance. The first of these is working across scale. This includes nested institutions as well as communication and coordination both horizontally and vertically between diverse governance groups. Second, we highlight the importance of collaboration. Building on the previous point, we draw on literature from collaborative governance and co-management to emphasize how collaboration can help to build more enduring governance structures. Third, we examine the importance of adaptation and evolution in the resolution of collective action dilemmas in complex systems filled with nonlinearities, unclear causal chains, and environments in which we have less than a full understanding of the ramifications of governance actions. Full article
(This article belongs to the Special Issue Environmental Governance for Sustainability)

Research

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Article
Food Connects Washington DC in 2050—A Vision for Urban Food Systems as the Centerpieces of a Circular Economy
Sustainability 2021, 13(14), 7821; https://0-doi-org.brum.beds.ac.uk/10.3390/su13147821 - 13 Jul 2021
Abstract
This article presents a vision for an urban food system in Washington DC in 2050 that serves as the centerpiece of a circular economy for the capital region of the United States. Food serves as the connecting link for an inclusive, adaptive, and [...] Read more.
This article presents a vision for an urban food system in Washington DC in 2050 that serves as the centerpiece of a circular economy for the capital region of the United States. Food serves as the connecting link for an inclusive, adaptive, and resilient urban economy embedded in the region. This food economy values natural resources, cultural diversity, and commitment to nature-based innovations. The vision is the result of a three-pronged methodology of: (1) community engagement; (2) a thoughtful, process-focused transformation; and (3) the scaling up of existing urban food initiatives. We argue that small, hyperlocal, neighborhood-based initiatives can become crucial game changers and catalysts of change for entire neighborhoods, cities, and regions. Therefore, we propose a design-based approach to advance our 2050 vision of a circular food system. Our design-based approach consists of three building blocks: (A) systems thinking; (B) the ability to manage wins and tradeoffs; and (C) transitional leadership and cooperation. We explain these building blocks and the way in which they are incorporated in the 2050 vision of Washington DC. We further argue that the food economy is an ideal sector to embark on such a design-based approach due to its systemic nature, its critical position as an indispensable economic sector, and the complex connections it brings to multiple other sectors of the economy. An urban food system can therefore offer the ideal starting point for a transition towards a circular economy. Full article
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Article
Sustainability Understanding and Behaviors across Urban Areas: A Case Study on Istanbul City
Sustainability 2021, 13(14), 7711; https://0-doi-org.brum.beds.ac.uk/10.3390/su13147711 - 09 Jul 2021
Abstract
The success of urban sustainability is very much dependent on a number of human factors. Therefore, it becomes even more important to explore how people understand urban sustainability and how they behave accordingly. Based on a formerly developed conceptual framework and on specified [...] Read more.
The success of urban sustainability is very much dependent on a number of human factors. Therefore, it becomes even more important to explore how people understand urban sustainability and how they behave accordingly. Based on a formerly developed conceptual framework and on specified influencing factors, this study aimed to evaluate and elucidate the urban sustainability understanding and behavior of individuals in the city of Istanbul. This was assessed through the use of a quantitative questionnaire survey of 535 respondents. Therein, socio-psychological processes of sustainability understanding (i.e., determinants of awareness, perception, and attitude) and sustainability behaviors along with personality traits and influential factors were assessed and analyzed through the use of bivariate and multivariate methods (i.e., correlation tests, ANOVA, t-tests, and multiple linear regression). The results showed that sustainability awareness was more strongly correlated with attitude than perception, whereas behavior was found to be strongly correlated with both awareness and attitude and was (significantly) predicted by all determinants. The associations/influences of personality traits with determinants were found to be mostly insignificant. Conversely, for behavior, they were significant. The most influential factors found (in hierarchical ordering) were awareness of consequences, trust in society, social appraisement, world-mindedness, willingness to pay, trust in science and technology, ascription of responsibility, age and gender. Full article
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Article
The Role of Community-Led Food Retailers in Enabling Urban Resilience
Sustainability 2021, 13(14), 7563; https://0-doi-org.brum.beds.ac.uk/10.3390/su13147563 - 06 Jul 2021
Abstract
Our research examines the extent to which community-led food retailers (CLFRs) contribute to the resilience and sustainability of urban retail systems and communities in the UK, contributing to existing debates on the sustainability and resilience of the UK’s urban retail sector. While existing [...] Read more.
Our research examines the extent to which community-led food retailers (CLFRs) contribute to the resilience and sustainability of urban retail systems and communities in the UK, contributing to existing debates on the sustainability and resilience of the UK’s urban retail sector. While existing literature has predominantly focused on larger retail multiples, we suggest more attention be paid to small, independent retailers as they possess a broader, more diffuse spatiality and societal impact than that of the immediate locale. Moreover, their local embeddedness and understanding of the needs of the local customer base provide a key source of potentially sustainable competitive advantage. Using spatial and relational resilience theories, and drawing on 14 original qualitative interviews with CLFRs, we establish the complex links between community, place, social relations, moral values, and resilience that manifest through CLFRs. In doing so, we advance the conceptualization of community resilience by acknowledging that in order to realise the networked, resilient capacities of a community, the moral values and behavior of the retail community need to be ascertained. Implications and relevant recommendations are provided to secure a more sustainable set of capacities needed to ensure resilient, urban retail systems which benefit local communities. Full article
(This article belongs to the Special Issue Urban Retail Systems: Vulnerability, Resilience and Sustainability)
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Article
Is Agent-Based Simulation a Valid Tool for Studying the Impact of Nature-Based Solutions on Local Economy? A Case Study of Four European Cities
Sustainability 2021, 13(13), 7466; https://0-doi-org.brum.beds.ac.uk/10.3390/su13137466 - 04 Jul 2021
Abstract
Implementing nature-based solutions (NBSs) in cities, such as urban forests, can have multiple effects on the quality of life of inhabitants, acting on the mitigation of climate change, and in some cases also enhancing citizens’ social life and the transformation of customer patterns [...] Read more.
Implementing nature-based solutions (NBSs) in cities, such as urban forests, can have multiple effects on the quality of life of inhabitants, acting on the mitigation of climate change, and in some cases also enhancing citizens’ social life and the transformation of customer patterns in commercial activities. Assessing this latter effect is the aim of this paper. An agent-based model (ABM) was used to assess change in commercial activities by small and midsize companies in retail due to the development of parks. The paper focuses on the potential capacity of NBS green spaces to boost retail companies’ business volumes, thus increasing their revenues, and at the same time create a pleasant feeling of space usability for the population. The type of NBS is not specified but generalized into large green spaces. The simulation contains two types of agents: (1) residents and (2) shop owners. Factors that attract new retail shops to be established in an area are simplified, based on attractor points, which identify areas such as large green spaces within and around which shops can form. The simulations provided insights on the number of retail shops that can be sustained based on the purchasing behavior of citizens that walk in parks. Four European cities were explored: Szeged (Hungary), Alcalá de Henares (Spain), Çankaya Municipality (Turkey) and Milan (Italy). The model allowed analyzing the indirect economic benefit of NBSs (i.e., large green spaces in this case) on a neighborhood’s economic structure. More precisely, the presence of green parks in the model boosted the visits of customers to local small shops located within and around them, such as cafés and kiosks, allowing for the emergence of 5–6 retail shops (on average, for about 800 walking citizens) in the case of Szeged and an average 12–14 retail shops for a simulated population of 2900 persons that walk in parks in the case of Milan. Overall, results from this modeling exercise can be considered representative for large urban green areas usually visited by a substantial number of citizens. However, their pertinence to support for local policies for NBS implementation and other decision-making related activities of socioeconomic nature is hampered by the low representativeness of source data used for the simulations. Full article
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Article
Collaboration for Community-Based Cultural Sustainability in Island Tourism Development: A Case in Korea
Sustainability 2021, 13(13), 7306; https://0-doi-org.brum.beds.ac.uk/10.3390/su13137306 - 30 Jun 2021
Abstract
Constructive collaboration with host communities while maintaining their traditional culture is crucial when planning tourism ventures, particularly if ensuring sustainability is considered important. This paper investigates the cultural sustainability of Jeju Island in South Korea and whether collaboration with community-based tourism ensures this [...] Read more.
Constructive collaboration with host communities while maintaining their traditional culture is crucial when planning tourism ventures, particularly if ensuring sustainability is considered important. This paper investigates the cultural sustainability of Jeju Island in South Korea and whether collaboration with community-based tourism ensures this sustainability through in-depth interviews with local residents. The first part of the interview focuses on cultural components to assess the current situation of cultural sustainability on the island, and the second part is related to that collaboration. The findings of the interviews indicate that: (i) there are certain negative indications of cultural sustainability in that Jeju people holding informal power became vulnerable in the face of tourism demand; (ii) several barriers exist in the facilitation of community-based tourism collaboration notwithstanding the beneficial trends, and (iii) there is a strong relationship between collaboration and cultural sustainability. It is also noted that the collaboration itself does not coincide with the actualization of cultural sustainability so long as current power disparities exist. The study delivers significant implications to the tourism policymakers and practitioners on how sustainable tourism development should be planned and operated to secure a long-term benefit especially focused on how the local community should be involved in the overall development process. Full article
(This article belongs to the Collection Culture and Development in Small and Medium-Sized Cities)
Article
Assessment of the Annual Transmission Heat Loss Reduction of a Refurbished Existing Building with an Advanced Solar Selective Thermal Insulation System
Sustainability 2021, 13(13), 7336; https://0-doi-org.brum.beds.ac.uk/10.3390/su13137336 - 30 Jun 2021
Abstract
A numerical parameter sensitivity analysis of the design parameters of the recently published solar selective thermal insulation system (SATIS) has been carried out to enhance its thermal and optical properties. It turned out that the insulation properties of SATIS can be effectively improved [...] Read more.
A numerical parameter sensitivity analysis of the design parameters of the recently published solar selective thermal insulation system (SATIS) has been carried out to enhance its thermal and optical properties. It turned out that the insulation properties of SATIS can be effectively improved by reducing the length of the glass closure element. Increasing the area share of the light conducting elements (LCEs) and decreasing their length-to-diameter (L/D) ratio were identified as key parameters in order to increase the solar gain. Two SATIS variants were compared with the same wall insulation without SATIS in a yearly energetic performance assessment. The SATIS variant with 10 mm length of the closure element, 44.2% area share of LCE, as well as front and rear diameters of 12 mm/9 mm shows an 11.8% lower transmission heat loss over the heating period than the wall insulation without SATIS. A new methodology was developed to enable the implementation of the computed solar gains of SATIS in 1D simulation tools. The result is a radiant heat flow map for integration as a heat source in 1D simulation models. A comparison between the 1D and 3D models of the inside wall heat fluxes showed an integral yearly agreement of 98%. Full article
(This article belongs to the Special Issue Thermal Behavior and Energy Efficiency of Buildings)
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Article
Mind the Gap: Why the Landscape Planning System in Sardinia Does Not Work
Sustainability 2021, 13(13), 7300; https://0-doi-org.brum.beds.ac.uk/10.3390/su13137300 - 29 Jun 2021
Abstract
In Italy, after the introduction of the Code of Cultural Heritage and Landscape in 2004, the Regional Landscape Plan (RLP) has acquired a coordination role in the urban planning system, for the implementation of policies for landscape protection and valorisation. The case study [...] Read more.
In Italy, after the introduction of the Code of Cultural Heritage and Landscape in 2004, the Regional Landscape Plan (RLP) has acquired a coordination role in the urban planning system, for the implementation of policies for landscape protection and valorisation. The case study of the RLP of Sardinia is a paradigmatic application to the coastal area of the island, which is considered most vulnerable and subject to settlement pressure. The objectives of preservation and valorisation of the territorial resources should be transferred into local planning instruments by adopting strategies aimed at the preservation of the consolidated urban fabric, at the requalification and completion of the existing built-up areas according to the principles of land take limitation and increase in urban quality. The paper investigates the state of implementation and the level of integration of landscape contents in the local plans that have been adapted to the RLP, using a qualitative comparative method. In addition, the results of the plan coherence checks, elaborated by the regional monitoring bodies after the adaptation process, have been analysed to identify the common criticalities and weaknesses. The results highlight the lack of effectiveness of the RLP, after more than a decade since its approval, considering the limited number of adequate local plans and the poor quality of their analytical and regulative contents in terms of landscape protection and valorisation. Conclusions suggest some possible ways to revise the RLP, focusing on the participation of local communities and the development of a new landscape culture. Full article
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Article
Optimal Operation of Low-Capacity Heat Pump Systems for Residential Buildings through Thermal Energy Storage
Sustainability 2021, 13(13), 7200; https://0-doi-org.brum.beds.ac.uk/10.3390/su13137200 - 27 Jun 2021
Abstract
The paper provides results from a hardware-in-the-loop experimental campaign on the operation of an air-source heat pump (HP) for heating a reference dwelling in Pisa, Italy. The system performances suffer from typical oversizing of heat emission devices and high water-supply temperature, resulting in [...] Read more.
The paper provides results from a hardware-in-the-loop experimental campaign on the operation of an air-source heat pump (HP) for heating a reference dwelling in Pisa, Italy. The system performances suffer from typical oversizing of heat emission devices and high water-supply temperature, resulting in HP inefficiencies, frequent on-off cycles, and relevant thermal losses on the hydronic loop. An experimentally validated HP model under different supply temperatures and part-load conditions is used to simulate the installation of a thermal storage between heat generator and emitters, in both series and parallel arrangements. Results relative to a typical residential apartment show that the presence of the thermal storage in series configuration ensures smoother heat pump operation and energy performance improvement. The number of daily on-off cycles can be reduced from 40 to 10, also saving one-third of electric energy with the same building loads. Preliminary guidelines are proposed for correctly sizing the tank in relation to the HP capacity and the average daily heating load of the building. A storage volume of about 70 L for each kilowatt of nominal heating capacity is suggested. Full article
(This article belongs to the Special Issue Optimized Energy and Comfort Management in Shared Smart Buildings)
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Article
Determination of NPS Pollutant Unit Loads from Different Landuses
Sustainability 2021, 13(13), 7193; https://0-doi-org.brum.beds.ac.uk/10.3390/su13137193 - 26 Jun 2021
Abstract
This study aimed to estimate pollutant unit loads for different landuses and pollutants that reflected long-term runoff characteristics of nonpoint source (NPS) pollutants and recent environmental changes. During 2008–2014, 2026 rainfall events were monitored. The average values of antecedent dry days, total rainfall, [...] Read more.
This study aimed to estimate pollutant unit loads for different landuses and pollutants that reflected long-term runoff characteristics of nonpoint source (NPS) pollutants and recent environmental changes. During 2008–2014, 2026 rainfall events were monitored. The average values of antecedent dry days, total rainfall, rainfall intensity, rainfall duration, runoff duration, and runoff coefficient for each landuse were 3.8–5.9 d, 35.2–65.0 mm, 2.9–4.1 mm/h, 12.5–20.4 h, 12.4–27.9 h, and 0.24–0.45, respectively. Uplands (UL) exhibited high suspended solids (SS, 606.2 mg/L), total nitrogen (TN, 7.38 mg/L), and total phosphorous (TP, 2.27 mg/L) levels, whereas the runoff coefficient was high in the building sites (BS), with a high impervious surface ratio. The event mean concentration (EMC) for biological oxygen demand (BOD) was the highest in BS (8.0 mg/L), while the EMC was the highest in BS (in the rainfall range <10 mm) and UL and forest land (in the rainfall range >50 mm). The unit loads for BOD (1.49–17.76 kg/km2·d), TN (1.462–10.147 kg/km2·d), TP (0.094–1.435 kg/km2·d), and SS (15.20–327.70 kg/km2·d) were calculated. The findings can be used to manage NPS pollutants and watershed environments and implement relevant associated management systems. Full article
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Article
Setting Thresholds to Define Indifferences and Preferences in PROMETHEE for Life Cycle Sustainability Assessment of European Hydrogen Production
Sustainability 2021, 13(13), 7009; https://0-doi-org.brum.beds.ac.uk/10.3390/su13137009 - 22 Jun 2021
Abstract
The Life Cycle Sustainability Assessment (LCSA) is a proven method for sustainability assessment. However, the interpretation phase of an LCSA is challenging because many different single results are obtained. Additionally, performing a Multi-Criteria Decision Analysis (MCDA) is one way—not only for LCSA—to gain [...] Read more.
The Life Cycle Sustainability Assessment (LCSA) is a proven method for sustainability assessment. However, the interpretation phase of an LCSA is challenging because many different single results are obtained. Additionally, performing a Multi-Criteria Decision Analysis (MCDA) is one way—not only for LCSA—to gain clarity about how to interpret the results. One common form of MCDAs are outranking methods. For these type of methods it becomes of utmost importance to clarify when results become preferable. Thus, thresholds are commonly used to prevent decisions based on results that are actually indifferent between the analyzed options. In this paper, a new approach is presented to identify and quantify such thresholds for Preference Ranking Organization METHod for Enrichment Evaluation (PROMETHEE) based on uncertainty of Life Cycle Impact Assessment (LCIA) methods. Common thresholds and this new approach are discussed using a case study on finding a preferred location for sustainable industrial hydrogen production, comparing three locations in European countries. The single LCSA results indicated different preferences for the environmental, economic and social assessment. The application of PROMETHEE helped to find a clear solution. The comparison of the newly-specified thresholds based on LCIA uncertainty with default thresholds provided important insights of how to interpret the LCSA results regarding industrial hydrogen production. Full article
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Article
People’s Avoidance of Neighboring Agricultural Urban Green Infrastructure: Evidence from a Choice Experiment
Sustainability 2021, 13(12), 6930; https://0-doi-org.brum.beds.ac.uk/10.3390/su13126930 - 20 Jun 2021
Abstract
This study evaluates people’s preferences regarding the proximity of their residence to agricultural urban green infrastructure (UGI), such as agricultural land and satoyama, and discusses the availability of these types of land as UGI. UGI is vital for reducing the negative environmental impacts [...] Read more.
This study evaluates people’s preferences regarding the proximity of their residence to agricultural urban green infrastructure (UGI), such as agricultural land and satoyama, and discusses the availability of these types of land as UGI. UGI is vital for reducing the negative environmental impacts of urban areas, as these impacts are too large to ignore. In this study, we conducted an online survey and a choice experiment to investigate people’s perceptions regarding the proximity of their residence to agricultural UGI (AUGI). The respondents of the choice experiment were 802 inhabitants of Ishikawa Prefecture, Japan, which has rich agricultural resources. To examine explicitly the spatial autocorrelation of people’s preferences, in this study, we used the spatial econometrics method. The main empirical findings are that people prefer agricultural land far away from their residence—more than 1000 m, not within 1000 m—which reflects the not-in-my-backyard phenomenon. Meanwhile, people’s preferences regarding proximity to satoyama are complicated and their preferences are positively spatially autocorrelated. The results indicate that policymakers and urban planners should manage and provide AUGI far away from residential areas; otherwise, they must address people’s avoidance of neighboring AUGI. Full article
(This article belongs to the Special Issue Non-market Valuation of Urban Green Space)
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Article
Numerical Analysis of Enhanced Conductive Deep Borehole Heat Exchangers
Sustainability 2021, 13(12), 6918; https://0-doi-org.brum.beds.ac.uk/10.3390/su13126918 - 19 Jun 2021
Abstract
Geothermal energy is a reliable and mature energy source, but it represents less than 1% of the total renewable energy mix. While the enhanced geothermal system (EGS) concept faces technical validation challenges and suffers from public acceptance issues, the development of unconventional deep-well [...] Read more.
Geothermal energy is a reliable and mature energy source, but it represents less than 1% of the total renewable energy mix. While the enhanced geothermal system (EGS) concept faces technical validation challenges and suffers from public acceptance issues, the development of unconventional deep-well designs can help to improve their efficiency and reliability. Modelling single-EGS-well designs is key to assessing their long-term thermal performances, particularly in unconventional geological settings. Numerical results obtained with the T2WELL/EOS1 code have been validated with available experimental data from a deep borehole heat exchanger (DBHE), where a temperature of 358 C has been measured at a depth of 1962 m. Based on a calibrated model, the thermal performances of two enhanced thermal conductive DBHEs with graphite were compared for high geothermal gradients. The analysis highlights the potential recovery of a variable fraction of vapour. Graphite used along the well appears to be the most suitable solution to enhance the thermal output by 5 to 8% when compared to conventional wells. The theoretical implementation of such well in the Newberry volcano field was investigated with a single and doublet DBHE. The findings provide a robust methodology to assess alternative engineering solutions to current geothermal practices. Full article
(This article belongs to the Special Issue Numerical Simulations and Optimization of Renewable Energy Systems)
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Article
CFD Investigation of Vehicle’s Ventilation Systems and Analysis of ACH in Typical Airplanes, Cars, and Buses
Sustainability 2021, 13(12), 6799; https://0-doi-org.brum.beds.ac.uk/10.3390/su13126799 - 16 Jun 2021
Cited by 1
Abstract
The simulation of the ventilation and the heating, ventilation, and air conditioning (HVAC) systems of vehicles could be used in the energy demand management of vehicles besides improving the air quality inside their cabins. Moreover, traveling by public transport during a pandemic is [...] Read more.
The simulation of the ventilation and the heating, ventilation, and air conditioning (HVAC) systems of vehicles could be used in the energy demand management of vehicles besides improving the air quality inside their cabins. Moreover, traveling by public transport during a pandemic is a concerning factor, and analysis of the vehicle’s cabin environments could demonstrate how to decrease the risk and create a safer journey for passengers. Therefore, this article presents airflow analysis, air changes per hour (ACH), and respiration aerosols’ trajectory inside three vehicles, including a typical car, bus, and airplane. In this regard, three vehicles’ cabin environment boundary conditions and the HVAC systems of the selected vehicles were determined, and three-dimensional numerical simulations were performed using computational fluid dynamic (CFD) modeling. The analysis of the airflow patterns and aerosol trajectories in the selected vehicles demonstrate the critical impact of inflow, outflow, and passenger’s locations in the cabins. The CFD model results exhibited that the lowest risk could be in the airplane and the highest in the bus because of the location of airflows and outflows. The discrete CFD model analysis determined the ACH for a typical car of about 4.3, a typical bus of about 7.5, and in a typical airplane of about 8.5, which were all less than the standard protocol of infection prevention, 12 ACH. According to the results, opening windows in the cars could decrease the aerosol loads and improve the low ACH by the HVAC systems. However, for the buses, a new design for the outflow location or an increase in the number of outflows appeared necessary. In the case of airplanes, the airflow paths were suitable, and by increasing the airflow speed, the required ACH might be achieved. Finally, in the closed (recirculating) systems, the role of filters in decreasing the risk appeared critical. Full article
(This article belongs to the Special Issue Feature Papers in Energy Sustainability)
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Article
Exploring Climate-Change Impacts on Energy Efficiency and Overheating Vulnerability of Bioclimatic Residential Buildings under Central European Climate
Sustainability 2021, 13(12), 6791; https://0-doi-org.brum.beds.ac.uk/10.3390/su13126791 - 16 Jun 2021
Abstract
Climate change is expected to expose the locked-in overheating risk concerning bioclimatic buildings adapted to a specific past climate state. The study aims to find energy-efficient building designs which are most resilient to overheating and increased cooling energy demands that will result from [...] Read more.
Climate change is expected to expose the locked-in overheating risk concerning bioclimatic buildings adapted to a specific past climate state. The study aims to find energy-efficient building designs which are most resilient to overheating and increased cooling energy demands that will result from ongoing climate change. Therefore, a comprehensive parametric study of various passive building design measures was implemented, simulating the energy use of each combination for a temperate climate of Ljubljana, Slovenia. The approach to overheating vulnerability assessment was devised and applied using the increase in cooling energy demand as a performance indicator. The results showed that a B1 heating energy efficiency class according to the Slovenian Energy Performance Certificate classification was the highest attainable using the selected passive design parameters, while the energy demand for heating is projected to decrease over time. In contrast, the energy use for cooling is in general projected to increase. Furthermore, it was found that, in building models with higher heating energy use, low overheating vulnerability is easier to achieve. However, in models with high heating energy efficiency, very high overheating vulnerability is not expected. Accordingly, buildings should be designed for current heating energy efficiency and low vulnerability to future overheating. The paper shows a novel approach to bioclimatic building design with global warming adaptation integrated into the design process. It delivers recommendations for the energy-efficient, robust bioclimatic design of residential buildings in the Central European context, which are intended to guide designers and policymakers towards a resilient and sustainable built environment. Full article
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Article
Evaluation of Thermal Comfort Performance of a Vertical Garden on a Glazed Façade and Its Effect on Building and Urban Scale, Case Study: An Office Building in Barcelona
Sustainability 2021, 13(12), 6706; https://0-doi-org.brum.beds.ac.uk/10.3390/su13126706 - 12 Jun 2021
Abstract
The aim of this paper is to investigate the thermal performance of vertical gardens by comparing the thermal comfort of bare (glazed) and green façades in the Mediterranean climate. The proposal consists of applying a vegetation layer on a glazed façade that could [...] Read more.
The aim of this paper is to investigate the thermal performance of vertical gardens by comparing the thermal comfort of bare (glazed) and green façades in the Mediterranean climate. The proposal consists of applying a vegetation layer on a glazed façade that could control solar radiation and reduce indoor air temperatures. This study investigates the thermal performance of green façades of an office building in the Mediterranean climate. For this purpose, the Gas Natural Fenosa Office Building as a case study was simulated, that is located on a site next to the coastline in Barcelona. Dynamic building energy simulation was used to determine and assess indoor thermal conditions and, for this reason, the IES VE as a simulation tool has been utilized. Thermal comfort was assessed through the adaptive comfort approach and results were analyzed and presented in the terms of indoor comfort conditions during occupied hours. As a result, the article shows that applying a green façade as a vegetation layer caused a reduction in the internal and external façade surface temperatures, as well as the indoor air temperature of the workplace. Additionally, enhancing indoor comfort in summer is closely associated with reducing the external surface temperature. In winter, it also protects the exterior surface from the low temperature of the outside, and all of this greatly increases thermal comfort performance. Full article
(This article belongs to the Special Issue Green Energy and Sustainable Development)
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Article
Dilemma of Geoconservation of Monogenetic Volcanic Sites under Fast Urbanization and Infrastructure Developments with Special Relevance to the Auckland Volcanic Field, New Zealand
Sustainability 2021, 13(12), 6549; https://0-doi-org.brum.beds.ac.uk/10.3390/su13126549 - 08 Jun 2021
Abstract
Geoheritage is an important aspect in developing workable strategies for natural hazard resilience. This is reflected in the UNESCO IGCP Project (# 692. Geoheritage for Geohazard Resilience) that continues to successfully develop global awareness of the multifaced aspects of geoheritage research. Geohazards form [...] Read more.
Geoheritage is an important aspect in developing workable strategies for natural hazard resilience. This is reflected in the UNESCO IGCP Project (# 692. Geoheritage for Geohazard Resilience) that continues to successfully develop global awareness of the multifaced aspects of geoheritage research. Geohazards form a great variety of natural phenomena that should be properly identified, and their importance communicated to all levels of society. This is especially the case in urban areas such as Auckland. The largest socio-economic urban center in New Zealand, Auckland faces potential volcanic hazards as it sits on an active Quaternary monogenetic volcanic field. Individual volcanic geosites of young eruptive products are considered to form the foundation of community outreach demonstrating causes and consequences of volcanism associated volcanism. However, in recent decades, rapid urban development has increased demand for raw materials and encroached on natural sites which would be ideal for such outreach. The dramatic loss of volcanic geoheritage of Auckland is alarming. Here we demonstrate that abandoned quarry sites (e.g., Wiri Mountain) could be used as key locations to serve these goals. We contrast the reality that Auckland sites are underutilized and fast diminishing, with positive examples known from similar but older volcanic regions, such as the Mio/Pliocene Bakony–Balaton UNESCO Global Geopark in Hungary. Full article
(This article belongs to the Special Issue Urban Disaster Risk Reduction)
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Article
Benthic Community Assessment of Commercial Oyster (Crassostrea virginica) Gear in Delaware Inland Bays
Sustainability 2021, 13(11), 6480; https://0-doi-org.brum.beds.ac.uk/10.3390/su13116480 - 07 Jun 2021
Abstract
Oyster aquaculture is one of several methods for the restoration of Delaware Inland Bays; however, little is known about its potential impacts on the benthic community of the bays. In this study, water quality parameters were measured and polychaetes were collected from 24 [...] Read more.
Oyster aquaculture is one of several methods for the restoration of Delaware Inland Bays; however, little is known about its potential impacts on the benthic community of the bays. In this study, water quality parameters were measured and polychaetes were collected from 24 sampling locations at Rehoboth, Indian River, and Little Assawoman Bays from July to October 2016 and 2017. We aimed to assess the impact of Eastern oyster farming under different stocking densities (50 and 250 oysters/gear) and distances away from the sites where the off-bottom gears are implemented (under gears, one meter, and five meters away). No significant impact was detected on polychaetes’ abundance and richness in regard to the presence of oyster gears. The number of polychaetes and species richness was significantly higher in Little Assawoman Bay in comparison to the Indian River and Rehoboth Bays. Results showed that the Ulva lactuca bloom that happened in 2016 could negatively impact the low abundance and richness observed in the polychaetes community. Similarly, the values of polychaetes abundance and species richness did not change significantly in samples that were taken far from the oyster gears. Dominant polychaetes families were Capitellidae and Glyceridae contributing to more than 70% of polychaetes’ number of individuals. Our results help to understand the role of oyster aquaculture in restoring the viability in the natural habitat of the Delaware Inland Bays. Full article
(This article belongs to the Collection Aquaculture and Environmental Impacts)
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Smart and Resilient Urban Futures for Sustainability in the Post COVID-19 Era: A Review of Policy Responses on Urban Mobility
Sustainability 2021, 13(11), 6486; https://0-doi-org.brum.beds.ac.uk/10.3390/su13116486 - 07 Jun 2021
Abstract
The COVID-19 pandemic has put lifestyles in question, changed daily routines, and limited citizen freedoms that seemed inalienable before. A human activity that has been greatly affected since the beginning of the health crisis is mobility. Focusing on mobility, we aim to discuss [...] Read more.
The COVID-19 pandemic has put lifestyles in question, changed daily routines, and limited citizen freedoms that seemed inalienable before. A human activity that has been greatly affected since the beginning of the health crisis is mobility. Focusing on mobility, we aim to discuss the transformational impact that the pandemic brought to this specific urban domain, especially with regards to the promotion of sustainability, the smart growth agenda, and the acceleration towards the smart city paradigm. We collect 60 initial policy responses related to urban mobility from cities around the world and analyze them based on the challenge they aim to address, the exact principles of smart growth and sustainable mobility that they encapsulate, as well as the level of ICT penetration. Our findings suggest that emerging strategies, although mainly temporary, are transformational, in line with the principles of smart growth and sustainable development. Most policy responses adopted during the first months of the pandemic, however, fail to leverage advancements made in the field of smart cities, and to adopt off-the-shelf solutions such as monitoring, alerting, and operations management. Full article
(This article belongs to the Section Sustainable Urban and Rural Development)
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Article
Psychological Restoration and the Effect of People in Nature and Urban Scenes: A Laboratory Experiment
Sustainability 2021, 13(11), 6464; https://0-doi-org.brum.beds.ac.uk/10.3390/su13116464 - 07 Jun 2021
Abstract
It is well-evidenced that exposure to natural environments increases psychological restoration as compared to non-natural settings, increasing our ability to recover from stress, low mood, and mental fatigue and encouraging positive social interactions that cultivate social cohesion. However, very few studies have explored [...] Read more.
It is well-evidenced that exposure to natural environments increases psychological restoration as compared to non-natural settings, increasing our ability to recover from stress, low mood, and mental fatigue and encouraging positive social interactions that cultivate social cohesion. However, very few studies have explored how the inclusion of people within a given environment—either urban or natural settings—affect restorative health outcomes. We present three laboratory-based studies examining, first, the effect of nature vs. urban scenes, and second, investigating nature ‘with’ vs. ‘without’ people—using static and moving imagery—on psychological restoration and social wellbeing. Our third study explores differences between urban and natural settings both with vs. without people, using video stimuli to understand potential restorative and social wellbeing effects. Outcome measures across all studies included perceived social belonging, loneliness, subjective mood, and perceived restorativeness. Studies 1 and 2 both used a within group, randomized crossover design. Study 1 (n = 45, mean age = 20.7) explored static imagery of environmental conditions without people; findings were consistent with restorative theories showing a positive effect of nature exposure on all outcome measures. Study 2 compared nature scenes with vs. without people (n = 47, mean age = 20.9) and we found no significant differences on our outcome measures between either social scenario, though both scenarios generated positive wellbeing outcomes. Study 3, conducted on Amazon Mechanical Turk, employed an independent group design with subjects randomly assigned to one of four conditions; an urban vs. nature setting, with vs. without people. We explored the effect of moving imagery on psychological restoration (n = 200, mean age = 35.7) and our findings showed no impact on belonging, loneliness, or mood between conditions, but did show that—regardless of the inclusion of people—the nature settings were more restorative than the urban. There were no differences in psychological restoration between nature conditions with vs. without people. We discuss the implications for restorative environment research exploring social-environmental interactions. Full article
(This article belongs to the Special Issue Landscape Architecture Design to Promote Well-Being)
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Article
Conventional and Conservation Seedbed Preparation Systems for Wheat Planting in Silty-Clay Soil
Sustainability 2021, 13(11), 6506; https://0-doi-org.brum.beds.ac.uk/10.3390/su13116506 - 07 Jun 2021
Abstract
Conventional seedbed preparation is based on deep ploughing followed by lighter and finer secondary tillage of the superficial layer, normally performed by machines powered by the tractor’s Power Take-Off (PTO), which prepares the seedbed in a single pass. Conservation methods are based on [...] Read more.
Conventional seedbed preparation is based on deep ploughing followed by lighter and finer secondary tillage of the superficial layer, normally performed by machines powered by the tractor’s Power Take-Off (PTO), which prepares the seedbed in a single pass. Conservation methods are based on a wide range of interventions, such as minimum or no-tillage, by means of machines with passive action working tools which require two or more passes The aim of this study was to assess both the power-energy requirements of conventional (power harrows and rotary tillers with different working width) and conservation implements (disks harrow and combined cultivator) and the soil tillage quality parameters, with reference to the capability of preparing an optimal seedbed for wheat planting. Field tests were carried out on flat, silty-clay soil, using instrumented tractors. The test results showed significant differences among the operative performances of the two typologies of machines powered by the tractor’s PTO: the fuel consumption, the power and the energy requirements of the rotary tillers are strongly higher than power harrows. However, the results also showed a decrease of these parameters proceeding from conventional to more conservation tillage implements. The better quality of seedbed was provided by the rotary tillers. Full article
(This article belongs to the Special Issue Soil Tillage Systems and Wheat Yield under Climate Change)
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Article
Dwelling Is a Key Idea in Traditional Residential Architecture’s Sustainability: A Case Study at Yangwan Village in Suzhou, China
Sustainability 2021, 13(11), 6492; https://0-doi-org.brum.beds.ac.uk/10.3390/su13116492 - 07 Jun 2021
Abstract
Previous studies have failed to grasp the essence of traditional building habits responding to natural challenges. Therefore, contradictions arise between unified regulations protecting traditional residential architecture proposed by experts and the diverse construction transformation performed by locals. To resolve these contradictions, fieldwork was [...] Read more.
Previous studies have failed to grasp the essence of traditional building habits responding to natural challenges. Therefore, contradictions arise between unified regulations protecting traditional residential architecture proposed by experts and the diverse construction transformation performed by locals. To resolve these contradictions, fieldwork was conducted in Yangwan, a famous village in South China. The traditional residential architectural characteristics in three periods were obtained and compared. Peirce’s interpretation of the three natures of habit and Heidegger’s dwelling help determine the essence of building habits. The logic in traditional residential architecture is analysed through the “four-layer integrated into one” framework (including the natural environment, livelihood form, institution and ideology), yielding the following results. (1) The characteristics of the residential architectural form change with local livelihood form, institution and ideology. Nevertheless, the process by which local residents think, judge and respond to natural challenges remains unchanged (Thirdness of Habit), forming the core of dwelling. (2) The characteristics of the architectural form are determined by the causal chain of “four-layer integrated into one”. Stable causal chains are formed by the Thirdness of Habit, which represents people’s initiative in addressing natural challenges. Therefore, the protection of traditional residential architecture should centre on dwelling and people’s agency in response to the natural environment rather than on maintaining a unified physical form. Full article
(This article belongs to the Special Issue Habit, Cultural Landscape and Sustainability)
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The Post-Pandemic Recovery of Transport Activity: Emerging Mobility Patterns and Repercussions on Future Evolution
Sustainability 2021, 13(11), 6359; https://0-doi-org.brum.beds.ac.uk/10.3390/su13116359 - 03 Jun 2021
Cited by 2
Abstract
The expectations for post-COVID recovery of transport activity point towards a gradual return to normality, once the pandemic is under control and mobility restrictions end. The shock to society and economy has, however, caused a number of behavioural changes that can influence the [...] Read more.
The expectations for post-COVID recovery of transport activity point towards a gradual return to normality, once the pandemic is under control and mobility restrictions end. The shock to society and economy has, however, caused a number of behavioural changes that can influence the evolution of the transport sector. We analyse the main factors that can influence future supply and demand and explore how they may affect trip generation, distribution and modal split in passenger transport. We combine several conventional and innovative data sources with a detailed strategic transport model at the EU level, in order to present quantitative estimates under various scenarios. New remote work patterns or personal risk avoidance attitudes can lead to increased levels of car ownership and use. Public policy priorities in the aftermath of the pandemic would need to address the emerging challenges and adopt measures that can sustain the shift to active travel, support public transport, railways and aviation and stimulate innovation in transport technologies and services. Full article
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Article
Data-Driven Analysis on Inter-City Commuting Decisions in Germany
Sustainability 2021, 13(11), 6320; https://0-doi-org.brum.beds.ac.uk/10.3390/su13116320 - 02 Jun 2021
Abstract
Understanding commuters’ behavior and influencing factors becomes more and more important every day. With the steady increase of the number of commuters, commuter traffic becomes a major bottleneck for many cities. Commuter behavior consequently plays an increasingly important role in city and transport [...] Read more.
Understanding commuters’ behavior and influencing factors becomes more and more important every day. With the steady increase of the number of commuters, commuter traffic becomes a major bottleneck for many cities. Commuter behavior consequently plays an increasingly important role in city and transport planning and policy making. Although prior studies investigated a variety of potential factors influencing commuting decisions, most of them are constrained by the data scale in terms of limited time duration, space and number of commuters under investigation, largely owing to their dependence on questionnaires or survey panel data; as such only small sets of features can be explored and no predictions of commuter numbers have been made, to the best of our knowledge. To fill this gap, we collected inter-city commuting data in Germany between 1994 and 2018, and, along with other data sources, analyzed the influence of GDP, housing and the labor market on the decision to commute. Our analysis suggests that the access to employment opportunities, housing price, income and the distribution of the location’s industry sectors are important factors in commuting decisions. In addition, different age, gender and income groups have different commuting patterns. We employed several machine learning algorithms to predict the commuter number using the identified related features with reasonably good accuracy. Full article
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A Method for the Automated Construction of 3D Models of Cities and Neighborhoods from Official Cadaster Data for Solar Analysis
Sustainability 2021, 13(11), 6028; https://0-doi-org.brum.beds.ac.uk/10.3390/su13116028 - 27 May 2021
Abstract
3D city models are a useful tool to analyze the solar potential of neighborhoods and cities. These models are built from buildings footprints and elevation measurements. Footprints are widely available, but elevation datasets remain expensive and time-consuming to acquire. Our hypothesis is that [...] Read more.
3D city models are a useful tool to analyze the solar potential of neighborhoods and cities. These models are built from buildings footprints and elevation measurements. Footprints are widely available, but elevation datasets remain expensive and time-consuming to acquire. Our hypothesis is that the GIS cadastral data can be used to build a 3D model automatically, so that generating complete cities 3D models can be done in a short time with already available data. We propose a method for the automatic construction of 3D models of cities and neighborhoods from 2D cadastral data and study their usefulness for solar analysis by comparing the results with those from a hand-built model. The results show that the accuracy in evaluating solar access on pedestrian areas and solar potential on rooftops with the automatic method is close to that from the hand-built model with slight differences of 3.4% and 2.2%, respectively. On the other hand, time saving with the automatic models is significant. A neighborhood of 400,000 m2 can be built up in 30 min, 50 times faster than by hand, and an entire city of 967 km2 can be built in 8.5 h. Full article
(This article belongs to the Section Sustainable Urban and Rural Development)
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Hydrogen vs. Battery-Based Propulsion Systems in Unipersonal Vehicles—Developing Solutions to Improve the Sustainability of Urban Mobility
Sustainability 2021, 13(10), 5721; https://0-doi-org.brum.beds.ac.uk/10.3390/su13105721 - 20 May 2021
Abstract
The percentage of the population in urban areas has increased by ten points from 2000 (46%) to 2020 (56%); it is expected to reach up to 70% by 2050. This undoubtedly will encourage society to use alternative transports. On the other hand, the [...] Read more.
The percentage of the population in urban areas has increased by ten points from 2000 (46%) to 2020 (56%); it is expected to reach up to 70% by 2050. This undoubtedly will encourage society to use alternative transports. On the other hand, the widespread fear of pandemics seems to be here to stay, and it is causing most people to leave public transport to use private cars, and a few have chosen unipersonal electric vehicles. As a consequence, the decision of using private cars negatively affects the air quality, and consequently urban population health. This paper aims to demonstrate a sustainable solution for urban mobility based on a hydrogen powered unipersonal electric vehicle, which, as shown, provides great advantages over the conventional battery powered unipersonal electric vehicle. To show this, the authors have developed both vehicles in comparable versions, using the same platform, and ensuring that the total weight of the unipersonal electric vehicle was the same in both cases. They have been subjected to experimental tests that support the features of the hydrogen-based configuration versus the battery-based one, including higher specific energy, more autonomy, and shorter recharge time. Full article
(This article belongs to the Section Energy Sustainability)
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Urban Structure in Troubled Times: The Evolution of Principal and Secondary Core/Periphery Gaps through the Prism of Residential Land Values
Sustainability 2021, 13(10), 5722; https://0-doi-org.brum.beds.ac.uk/10.3390/su13105722 - 20 May 2021
Abstract
The structure of modern cities is characterized by the uneven spatial distribution of people and activities. Contrary to economic theory, it is neither evenly distributed nor entirely monocentric. The observed reality is the result of various feedbacks in the context of the interactions [...] Read more.
The structure of modern cities is characterized by the uneven spatial distribution of people and activities. Contrary to economic theory, it is neither evenly distributed nor entirely monocentric. The observed reality is the result of various feedbacks in the context of the interactions of attraction and repulsion. Heretofore, there is no agreement concerning the means to measuring the dimensions of these interactions, nor the framework for explaining them. We propose a simple model and an associated method for testing the interactions using residential land values. We claim that land values reflect the attractiveness of each location, including its observable and unobservable characteristics. We extract land values from prices of residences by applying a dedicated hedonic model to extensive residential real estate transaction data at a detailed spatial level. The resulting land values reflect the attractiveness of each urban location and are an ideal candidate to measure the degree of centrality or peripherality of each location. Moreover, assessment of land values over time indicates ongoing centralization and peripheralization processes. Using the urban structure of a small and highly urbanized country as a test case, this paper illustrates how the dynamics of the gap between central and peripheral urban areas can be assessed. Full article
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Spatial Heterogeneity and Complexity of the Impact of Extreme Climate on Vegetation in China
Sustainability 2021, 13(10), 5748; https://0-doi-org.brum.beds.ac.uk/10.3390/su13105748 - 20 May 2021
Abstract
The impact of extreme climate on natural ecosystems and socioeconomic systems is more serious than that of the climate’s mean state. Based on the data of 1698 meteorological stations in China from 2001 to 2018, this study calculated the 27 extreme climate indices [...] Read more.
The impact of extreme climate on natural ecosystems and socioeconomic systems is more serious than that of the climate’s mean state. Based on the data of 1698 meteorological stations in China from 2001 to 2018, this study calculated the 27 extreme climate indices of the Expert Team on Climate Change Detection and Indices (ETCCDI). Through correlation analysis and collinearity diagnostics, we selected two representative extreme temperature indices and three extreme precipitation indices. The spatial scale of the impact of extreme climate on Normalized Difference Vegetation Index (NDVI) in China during the growing season from 2001 to 2018 was quantitatively analyzed, and the complexity of the dominant factors in different regions was discussed via clustering analysis. The research results show that extreme climate indices have a scale effect on vegetation. There are spatial heterogeneities in the impacts of different extreme climate indices on vegetation, and these impacts varied between the local, regional and national scales. The relationship between the maximum length of a dry spell (CDD) and NDVI was the most spatially nonstationary, and mostly occurred on the local scale, while the effect of annual total precipitation when the daily precipitation amount was more than the 95th percentile (R95pTOT) showed the greatest spatial stability, and mainly manifested at the national scale. Under the current extreme climate conditions, extreme precipitation promotes vegetation growth, while the influence of extreme temperature is more complicated. As regards intensity and range, the impact of extreme climate on NDVI in China over the past 18 years can be categorized into five types: the humidity-promoting type, the cold-promoting and drought-inhibiting compound type, the drought-inhibiting type, the heat-promoting and drought-inhibiting compound type, and the heat-promoting and humidity-promoting compound type. Drought is the greatest threat to vegetation associated with extreme climate in China. Full article
(This article belongs to the Section Air, Climate Change and Sustainability)
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Article
Circular Cities: What Are the Benefits of Circular Development?
Sustainability 2021, 13(10), 5725; https://0-doi-org.brum.beds.ac.uk/10.3390/su13105725 - 20 May 2021
Abstract
If cities could become regenerative and adaptive urban ecosystems, in which resource loops were closed and waste was obsolete, their ecological footprint would diminish. In addition, urban resource security would increase, the health of urban populations would improve and urban greenhouse gas emissions [...] Read more.
If cities could become regenerative and adaptive urban ecosystems, in which resource loops were closed and waste was obsolete, their ecological footprint would diminish. In addition, urban resource security would increase, the health of urban populations would improve and urban greenhouse gas emissions would be reduced. These are the principle goals under-pinning the circular city. Circular cities emerge through the process of circular development. Circular development alters cities’ systems of provision to enable circular practices of inhabitants to develop. This manifests as circular food systems and construction, water and nutrient recycling; adaptive reuse of spaces and pop-up activities; bioremediation of contaminated sites and integration of blue-green infrastructure throughout cities. To transform our cities will require significant investment, political support and public engagement. If the benefits of adopting such an approach can be identified, this will begin to make the case for support. The research presented in this paper draws on an inductive and deductive content analysis of relevant literature and interviews with those implementing circular projects in European cities (London, Paris, Amsterdam and Stockholm). It provides a clear definition of the normative concept of circular development. It creates a framework of benefits which are likely to accrue from adopting this approach. It points to the synergistic benefits emerging from circular development. It also highlights problems around valuation of those benefits, the unintended consequences of circular development and the inequalities in accessing benefits across society. Full article
(This article belongs to the Section Sustainable Urban and Rural Development)
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Article
Stochastic Expansion Planning of Various Energy Storage Technologies in Active Power Distribution Networks
Sustainability 2021, 13(10), 5752; https://0-doi-org.brum.beds.ac.uk/10.3390/su13105752 - 20 May 2021
Abstract
This work aims to minimize the cost of installing renewable energy resources (photovoltaic systems) as well as energy storage systems (batteries), in addition to the cost of operation over a period of 20 years, which will include the cost of operating the power [...] Read more.
This work aims to minimize the cost of installing renewable energy resources (photovoltaic systems) as well as energy storage systems (batteries), in addition to the cost of operation over a period of 20 years, which will include the cost of operating the power grid and the charging and discharging of the batteries. To this end, we propose a long-term planning optimization and expansion framework for a smart distribution network. A second order cone programming (SOCP) algorithm is utilized in this work to model the power flow equations. The minimization is computed in accordance to the years (y), seasons (s), days of the week (d), time of the day (t), and different scenarios based on the usage of energy and its production (c). An IEEE 33-bus balanced distribution test bench is utilized to evaluate the performance, effectiveness, and reliability of the proposed optimization and forecasting model. The numerical studies are conducted on two of the highest performing batteries in the current market, i.e., Lithium-ion (Li-ion) and redox flow batteries (RFBs). In addition, the pros and cons of distributed Li-ion batteries are compared with centralized RFBs. The results are presented to showcase the economic profits of utilizing these battery technologies. Full article
(This article belongs to the Special Issue Energy Management of Multi-Energy Storage Systems)
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Article
Urban Planning Policies to the Renewal of Riverfront Areas: The Lisbon Metropolis Case
Sustainability 2021, 13(10), 5665; https://0-doi-org.brum.beds.ac.uk/10.3390/su13105665 - 18 May 2021
Abstract
Urban planning offers various design possibilities to solve fundamental challenges faced in urban areas. These include the need to physically renew old industrial and harbour riverside areas into liveable, inclusive and sustainable living spaces. This paper investigates the way urban planning policies have [...] Read more.
Urban planning offers various design possibilities to solve fundamental challenges faced in urban areas. These include the need to physically renew old industrial and harbour riverside areas into liveable, inclusive and sustainable living spaces. This paper investigates the way urban planning policies have helped to renew the waterfront areas in the Lisbon metropolis in the past decades. For this purpose, the contribution of the European Union (EU) and national urban development plans over the past decades are analysed. The results demonstrate an intense renewal of the waterfront areas in the Lisbon metropolitan area (LMA), particularly in Lisbon over the past three decades into leisure, ecologic and touristic areas, vis-à-vis the previous industrial and harbour vocation. Full article
(This article belongs to the Special Issue Urban Legacies of the Late 20th Century)
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Article
Towns, High Streets and Resilience in Scotland: A Question for Policy?
Sustainability 2021, 13(10), 5631; https://0-doi-org.brum.beds.ac.uk/10.3390/su13105631 - 18 May 2021
Cited by 1
Abstract
The “death of the high street” has become a common refrain, particularly in the United Kingdom, often accompanied by calls for action and demands for improved resilience in town centres and high streets. This paper considers the policy context for towns and town [...] Read more.
The “death of the high street” has become a common refrain, particularly in the United Kingdom, often accompanied by calls for action and demands for improved resilience in town centres and high streets. This paper considers the policy context for towns and town centres in Scotland and the recent review of the country’s approach to towns, town centres and places. With the adoption of National Outcomes linked to the United Nations Sustainable Development Goals and the declaration of a Climate Emergency, the conclusion is drawn that a more fundamental and radical shift in policy is needed, if the resilience of town centres is to have any meaning, and that a clearer and more widely understood conceptualisation of resilience needs to be developed. Full article
(This article belongs to the Special Issue Urban Retail Systems: Vulnerability, Resilience and Sustainability)
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Article
Stakeholder Expectations of Future Policy Implementation Compared to Formal Policy Trajectories: Scenarios for Agricultural Food Systems in the Mekong Delta
Sustainability 2021, 13(10), 5534; https://0-doi-org.brum.beds.ac.uk/10.3390/su13105534 - 15 May 2021
Cited by 1
Abstract
The development of a coherent and coordinated policy for the management of large socio-agricultural systems, such as the Mekong delta in southern Vietnam, is reliant on aligning the development, delivery, and implementation of policy on national to local scales. Effective decision making is [...] Read more.
The development of a coherent and coordinated policy for the management of large socio-agricultural systems, such as the Mekong delta in southern Vietnam, is reliant on aligning the development, delivery, and implementation of policy on national to local scales. Effective decision making is linked to a coherent, broadly-shared vision of the strategic management of socio-agricultural systems. However, when policies are ambiguous, and at worst contradictory, long-term management and planning can consequently suffer. These potential adverse impacts may be compounded if stakeholders have divergent visions of the current and future states of socio-agricultural systems. Herein we used a transferable, scenario-based methodology which uses a standard quadrant matrix in order to explore both anticipated and idealized future states. Our case study was the Mekong delta. The scenario matrix was based upon two key strategic choices (axis) for the delta, derived from analysis of policy documents, literature, stakeholder engagement, and land use models. These are: (i) who will run agriculture in the future, agri-business or the established commune system; and (ii) to what degree sustainability will be incorporated into production. During a workshop meeting, stakeholders identified that agri-business will dominate future agricultural production in the delta but showed a clear concern that sustainability might consequently be undermined despite policy claims of the contrary. As such, our study highlights an important gap between national expectations and regional perspectives. Our results suggest that the new development plans for the Mekong delta (which comprise a new Master Plan and a new 5-year socio-economic development plan), which emphasize agro-business development, should adopt approaches that address concerns of sustainability as well as a more streamlined policy formulation and implementation that accounts for stakeholder concerns at both provincial and national levels. Full article
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Geo-Crowdsourced Sound Level Data in Support of the Community Facilities Planning. A Methodological Proposal
Sustainability 2021, 13(10), 5486; https://0-doi-org.brum.beds.ac.uk/10.3390/su13105486 - 14 May 2021
Abstract
To reduce environmental noise pollution and to safeguard people’s well-being, it is urgently necessary to move towards sustainable urban development and reconcile demographic and economic growth with the protection and restoration of the environment and the improvement of the quality of human lives. [...] Read more.
To reduce environmental noise pollution and to safeguard people’s well-being, it is urgently necessary to move towards sustainable urban development and reconcile demographic and economic growth with the protection and restoration of the environment and the improvement of the quality of human lives. This challenge should be a concern to policymakers, who must issue regulations and define the appropriate actions for noise monitoring and management, and citizens, who must be sensitive to the problem and act accordingly. Starting from an analysis of several crowdsourcing noise data collection tools, this paper focuses on the definition of a methodology for data analysis and mapping. The sound sensing system, indeed, enables mobile devices, such as smartphones and tablets, to become a low-cost data collection for monitoring environmental noise. For this study, the “NoiseCapture” application developed in France by CNRS and IFSTTAR has been utilized. The measurements acquired in 2018 and 2019 at the Fisciano Campus at the University of Salerno were integrated with the kernel density estimation. This is a spatial analysis technique that allows for the elaboration of sound level density maps, defined spatially and temporally. These maps, overlaid on a campus facilities map, can become tools to support the appropriate mitigation actions. Full article
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Article
Analysis of District Heating and Cooling Energy Systems in Spain: Resources, Technology and Management
Sustainability 2021, 13(10), 5442; https://0-doi-org.brum.beds.ac.uk/10.3390/su13105442 - 13 May 2021
Abstract
District heating and cooling (DHC) systems play an important role under the new European Union (EU) energy transition strategy. Thermal energy networks are helping to stimulate the development of alternative technologies based on a broad range of renewable energy sources. The present study [...] Read more.
District heating and cooling (DHC) systems play an important role under the new European Union (EU) energy transition strategy. Thermal energy networks are helping to stimulate the development of alternative technologies based on a broad range of renewable energy sources. The present study analysed the current situation of DHC systems in Spain and provides an overview of the challenges and future opportunities that their use will entail. Its objective is to assess thermal energy conversion and management from a holistic perspective, including a study of existing energy infrastructures. The focus of this study lies on Spain given the country’s abundance of natural resources such as renewable energy sources including solar energy, biomass and geothermal energy, among others, as well as its strategic location on the map of the EU. Based on the analysis of the three factors for energy conversion in a district heating system, namely resources, technology, and management, the methodology provided an assessment of the different factors involved in running a DHC system. The results show an estimated total production for DHC networks of 1448 MWth, of which 72% is supplied purely by renewable energy sources. Full article
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Article
Perceived Sensory Dimensions of Green Areas: An Experimental Study on Stress Recovery
Sustainability 2021, 13(10), 5419; https://0-doi-org.brum.beds.ac.uk/10.3390/su13105419 - 12 May 2021
Abstract
Natural environments have been shown to promote health, and are, therefore, important for achieving social sustainability in cities. As cities grow and become denser, it is important to develop knowledge about the characteristics of natural environments that work to promote health. Perceived Sensory [...] Read more.
Natural environments have been shown to promote health, and are, therefore, important for achieving social sustainability in cities. As cities grow and become denser, it is important to develop knowledge about the characteristics of natural environments that work to promote health. Perceived Sensory Dimensions (PSDs) is a tool that defines eight different cultural ecosystem services. They correspond to different human needs (rest, exercise, socialising, pleasure, or security) resulting in rehabilitation and health and well-being promotion. An experiment was conducted to study the potential of PSDs to restore people who experienced stressful accidents. One hundred and fifty-seven participants were recruited and asked first to watch a film clip of serious accidents, then to look at the pictures, depicting one particular type of PSDs, while listening to its respective audio recording. Their stress levels were measured before exposure to the stressor (baseline), after exposure to the stressor (pre-test), and after exposure to a particular type of PSDs (post-test). The results show that all eight PSDs effectively provide mental recovery, but there are statistical differences in their potentials. As such, it is proposed that the combined potential of the PSDs is needed, and should be used to increase the capacity and supply of health-promoting urban green areas. Full article
(This article belongs to the Special Issue Landscape Architecture Design to Promote Well-Being)
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Article
Transport Airships for Scheduled Supply and Emergency Response in the Arctic
Sustainability 2021, 13(9), 5301; https://0-doi-org.brum.beds.ac.uk/10.3390/su13095301 - 10 May 2021
Abstract
As climate change progresses, the Arctic Ocean creates opportunities for new resource development and navigation routes. Such economic opportunities are attractive, but carry with them an increased risk of accidents and oil spills. Existing methods of emergency response face enormous challenges in the [...] Read more.
As climate change progresses, the Arctic Ocean creates opportunities for new resource development and navigation routes. Such economic opportunities are attractive, but carry with them an increased risk of accidents and oil spills. Existing methods of emergency response face enormous challenges in the Arctic because of its lack of transportation infrastructure and support services. Cargo airships offer a practical solution. Many airship designs are proposed that can carry over 30 tons, travel long distances at 150 km per hour, and land close to the emergency site. However, it is difficult to justify the economics of having enough capacity waiting and available to be marshaled in response to infrequent events. One solution is to develop a synergy with a new civilian cargo airship industry that can serve the regular transport needs of remote communities and mining operations. Through contingency contracts with these civilian operations, the Government of Canada could stretch its budgets and have access to the latest airship models and trained crews at locations across the Arctic. This paper gives valuable insight into the development of cargo airships. Advances in technology that make cargo airships a practical option in the 21st century are reviewed, and five competing airship designs are discussed. A case study of an existing rare earth mine proposal is used to illustrate the cost comparison of roads versus airships that could provide contingency services. Full article
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Life Cycle Assessment (LCA) of an Innovative Compact Hybrid Electrical-Thermal Storage System for Residential Buildings in Mediterranean Climate
Sustainability 2021, 13(9), 5322; https://0-doi-org.brum.beds.ac.uk/10.3390/su13095322 - 10 May 2021
Abstract
The buildings sector is one of the least sustainable activities in the world, accounting for around 40% of the total global energy demand. With the aim to reduce the environmental impact of this sector, the use of renewable energy sources coupled with energy [...] Read more.
The buildings sector is one of the least sustainable activities in the world, accounting for around 40% of the total global energy demand. With the aim to reduce the environmental impact of this sector, the use of renewable energy sources coupled with energy storage systems in buildings has been investigated in recent years. Innovative solutions for cooling, heating, and domestic hot water in buildings can contribute to the buildings’ decarbonization by achieving a reduction of building electrical consumption needed to keep comfortable conditions. However, the environmental impact of a new system is not only related to its electrical consumption from the grid, but also to the environmental load produced in the manufacturing and disposal stages of system components. This study investigates the environmental impact of an innovative system proposed for residential buildings in Mediterranean climate through a life cycle assessment. The results show that, due to the complexity of the system, the manufacturing and disposal stages have a high environmental impact, which is not compensated by the reduction of the impact during the operational stage. A parametric study was also performed to investigate the effect of the design of the storage system on the overall system impact. Full article
(This article belongs to the Special Issue Life-Cycle Assessment of Energy Storage in Building Applications)
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Article
Automatic Detection of Photovoltaic Farms Using Satellite Imagery and Convolutional Neural Networks
Sustainability 2021, 13(9), 5323; https://0-doi-org.brum.beds.ac.uk/10.3390/su13095323 - 10 May 2021
Abstract
The number of solar photovoltaic (PV) arrays in Greece has increased rapidly during the recent years. As a result, there is an increasing need for high quality updated information regarding the status of PV farms. This information includes the number of PV farms, [...] Read more.
The number of solar photovoltaic (PV) arrays in Greece has increased rapidly during the recent years. As a result, there is an increasing need for high quality updated information regarding the status of PV farms. This information includes the number of PV farms, power capacity and the energy generated. However, access to this data is obsolete, mainly due to the fact that there is a difficulty tracking PV investment status (from licensing to investment completion and energy production). This article presents a novel approach, which uses free access high resolution satellite imagery and a deep learning algorithm (a convolutional neural network—CNN) for the automatic detection of PV farms. Furthermore, in an effort to create an algorithm capable of generalizing better, all the current locations with installed PV farms (data provided from the Greek Energy Regulator Authority) in the Greek Territory (131,957 km2) were used. According to our knowledge this is the first time such an algorithm is used in order to determine the existence of PV farms and the results showed satisfying accuracy. Full article
(This article belongs to the Special Issue Energy Transition and Climate Change in Decision-making Processes)
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Article
How to Sustain Sustainability Monitoring in Cities: Lessons from 49 Community Indicator Initiatives across 10 Latin American Countries
Sustainability 2021, 13(9), 5133; https://0-doi-org.brum.beds.ac.uk/10.3390/su13095133 - 04 May 2021
Abstract
Since the 1990s, many countries have witnessed the emergence of organizations publishing environmental, social, and quality-of-life indicators at a city level in order to promote public awareness, democratic participation, and sustainability policies. Many such initiatives are short-lived, however, and reasons for their success [...] Read more.
Since the 1990s, many countries have witnessed the emergence of organizations publishing environmental, social, and quality-of-life indicators at a city level in order to promote public awareness, democratic participation, and sustainability policies. Many such initiatives are short-lived, however, and reasons for their success and failure under-researched. Using interviews, surveys, and documental data, we explored the survival rates, obstacles, and achievements of 49 initiatives in 10 Latin American countries. Contrary to those in other world regions, most initiatives have civil society stakeholders (notably universities, media, and businesses), excluding governments. Implementing citizen perception surveys proved effective to gain public attention. Several initiatives obtained name recognition and policy influence, which are significant achievements in megacities such as Bogotá, São Paulo, and Lima, where numerous NGOs vie for attention. Frequent obstacles include a lack of finances. After a seven-year period (2014–2021), 55% of the sampled initiatives remained active, ranging from 90% in Colombia to none in other countries. Organizational continuity appeared to be associated with network membership and discontinuity with diverging obstacles, including political pressures in some countries (e.g., Mexico), data scarcity in poorer ones (e.g., Bolivia), and a lack of sustained interest in relatively richer ones (e.g., Chile). Recent increases in socio-economic inequalities are strengthening the potential of community indicators. Full article
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Article
Nature-Based Solutions and Sustainable Urban Planning in the European Environmental Policy Framework: Analysis of the State of the Art and Recommendations for Future Development
Sustainability 2021, 13(9), 5021; https://0-doi-org.brum.beds.ac.uk/10.3390/su13095021 - 29 Apr 2021
Abstract
Sustainable urban planning (SUP) is crucial in the development of sustainable cities, as also underlined by the New Urban Agenda. Nature-based solutions (NBS) are increasingly being recognized for their potential to offer multiple benefits that are necessary in order to cope with present [...] Read more.
Sustainable urban planning (SUP) is crucial in the development of sustainable cities, as also underlined by the New Urban Agenda. Nature-based solutions (NBS) are increasingly being recognized for their potential to offer multiple benefits that are necessary in order to cope with present and future urban challenges. The European policy framework, including the recently released European Green Deal, could strongly boost the role and recognition of NBS and SUP as drivers of sustainable and inclusive urban transition. Through a content analysis of current environmental European policies, strategies and agreements, this paper provides (i) an overview of the state of the art of the environmental European policy framework and the recognized role of NBS and SUP in reaching defined objectives, and (ii) insights on where NBS and SUP could play a larger role within this framework. On this basis, the paper identifies gaps and develops recommendations for a better integration of such concepts into the current framework. Full article
(This article belongs to the Special Issue Towards a Sustainable Urban Planning for the Green Deal Era)
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Article
Environmental Sustainability of Building Retrofit through Vertical Greening Systems: A Life-Cycle Approach
Sustainability 2021, 13(9), 4886; https://0-doi-org.brum.beds.ac.uk/10.3390/su13094886 - 27 Apr 2021
Abstract
Urban greening provides a wide range of ecosystem services to address the main challenges of urban areas, e.g., carbon sequestration, evapotranspiration and shade, thermal insulation, and pollution control. This study evaluates the environmental sustainability of a vertical greening system (VGS) built in 2014 [...] Read more.
Urban greening provides a wide range of ecosystem services to address the main challenges of urban areas, e.g., carbon sequestration, evapotranspiration and shade, thermal insulation, and pollution control. This study evaluates the environmental sustainability of a vertical greening system (VGS) built in 2014 in Italy, for which extensive monitoring activities were implemented. The life-cycle assessment methodology was applied to quantify the water–energy–climate nexus of the VGS for 1 m2 of the building’s wall surface. Six different scenarios were modelled according to three different end-of-life scenarios and two different useful lifetime scenarios (10 and 25 years). The environmental impact of global-warming potential and generated energy consumption during the use phase in the VGS scenarios were reduced by 56% in relation to the baseline scenario (wall without VGS), and showed improved environmental performance throughout the complete life cycle. However, the water-scarcity index (WSI) of the VGS scenarios increased by 42%. This study confirms that the installation of VGSs offers a relevant environmental benefit in terms of greenhouse-gas emissions and energy consumption; however, increased water consumption in the use phase may limit the large-scale application of VGSs. Full article
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Article
Local and Application-Specific Geodemographics for Data-Led Urban Decision Making
Sustainability 2021, 13(9), 4873; https://0-doi-org.brum.beds.ac.uk/10.3390/su13094873 - 26 Apr 2021
Abstract
This work seeks to introduce improvements to the traditional variable selection procedures employed in the development of geodemographic classifications. It presents a proposal for shifting from a traditional approach for generating general-purpose one-size-fits-all geodemographic classifications to application-specific classifications. This proposal addresses the recent [...] Read more.
This work seeks to introduce improvements to the traditional variable selection procedures employed in the development of geodemographic classifications. It presents a proposal for shifting from a traditional approach for generating general-purpose one-size-fits-all geodemographic classifications to application-specific classifications. This proposal addresses the recent scepticism towards the utility of general-purpose applications by employing supervised machine learning techniques in order to identify contextually relevant input variables from which to develop geodemographic classifications with increased discriminatory power. A framework introducing such techniques in the variable selection phase of geodemographic classification development is presented via a practical use-case that is focused on generating a geodemographic classification with an increased capacity for discriminating the propensity for Library use in the UK city of Leeds. Two local classifications are generated for the city, one a general-purpose classification, and the other, an application-specific classification incorporating supervised Feature Selection methods in the selection of input variables. The discriminatory power of each classification is evaluated and compared, with the result successfully demonstrating the capacity for the application-specific approach to generate a more contextually relevant result, and thus underpins increasingly targeted public policy decision making, particularly in the context of urban planning. Full article
(This article belongs to the Special Issue Advanced Modelling Tools to Support Urban and Regional Planning)
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Article
Cycling in the Era of COVID-19: Lessons Learnt and Best Practice Policy Recommendations for a More Bike-Centric Future
Sustainability 2021, 13(9), 4620; https://0-doi-org.brum.beds.ac.uk/10.3390/su13094620 - 21 Apr 2021
Cited by 2
Abstract
The COVID-19 pandemic has affected our cities in monumental ways with no sector likely being more severely impacted than transport. Lockdowns, physical spacing, transport restrictions and stay-at-home guidelines have transformed personal mobility and highlighted the mistakes of an unbalanced pro-car culture that defined [...] Read more.
The COVID-19 pandemic has affected our cities in monumental ways with no sector likely being more severely impacted than transport. Lockdowns, physical spacing, transport restrictions and stay-at-home guidelines have transformed personal mobility and highlighted the mistakes of an unbalanced pro-car culture that defined a century of urban planning. One immediate effect of the virus in relation to travel demand and supply was the emergence of active travel modes because of their unique ability to provide a socially distanced way of transport. Cycling is one of the modes that has enjoyed significant attention. Numerous cities have reallocated street and public space to cyclists and introduced pro-bike interventions like pop-up cycle lanes, e-bike subsidies, free bike-share use and traffic calming measures. This newly found outbreak-induced momentum creates an opportunity to establish a new ethos that allows the promotion of potentially permanent strategies that may help cycling to be (re-)established as a robust, mainstream and resilient travel mode for inner city trips and not as a second-class alternative operating under the automobile’s giant shadow. This paper provides a state-of-the-art description of the anti-COVID cycling-friendly initiatives that have been introduced globally, the successes and failures of these initiatives, the lessons learnt that can help us redefine the bicycle’s role in local societies today and a best cycling practice policy guide for planning a more bike-centric future. Full article
Article
How the SP System May Promote Sustainability in Energy Consumption in IT Systems
Sustainability 2021, 13(8), 4565; https://0-doi-org.brum.beds.ac.uk/10.3390/su13084565 - 20 Apr 2021
Abstract
The SP System (SPS), referring to the SP Theory of Intelligence and its realisation as the SP Computer Model, has the potential to reduce demands for energy from IT, especially in AI applications and in the processing of big data, in addition [...] Read more.
The SP System (SPS), referring to the SP Theory of Intelligence and its realisation as the SP Computer Model, has the potential to reduce demands for energy from IT, especially in AI applications and in the processing of big data, in addition to reductions in CO2 emissions when the energy comes from the burning of fossil fuels. The biological foundations of the SPS suggest that with further development, the SPS may approach the extraordinarily low (20 W)energy demands of the human brain. Some of these savings may arise in the SPS because, like people, the SPS may learn usable knowledge from a single exposure or experience. As a comparison, deep neural networks (DNNs) need many repetitions, with much consumption of energy, for the learning of one concept. Another potential saving with the SPS is that like people, it can incorporate old learning in new. This contrasts with DNNs where new learning wipes out old learning (‘catastrophic forgetting’). Other ways in which the mature SPS is likely to prove relatively parsimonious in its demands for energy arise from the central role of information compression (IC) in the organisation and workings of the system: by making data smaller, there is less to process; because the efficiency of searching for matches between patterns can be improved by exploiting probabilities that arise from the intimate connection between IC and probabilities; and because, with SPS-derived ’Model-Based Codings’ of data, there can be substantial reductions in the demand for energy in transmitting data from one place to another. Full article
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Article
Particulate Matter Short-Term Exposition, Mobility Trips and COVID-19 Diffusion: A Correlation Analyses for the Italian Case Study at Urban Scale
Sustainability 2021, 13(8), 4553; https://0-doi-org.brum.beds.ac.uk/10.3390/su13084553 - 20 Apr 2021
Cited by 2
Abstract
The conjecture discussed in this paper was that the daily number of certified cases of COVID-19 is direct correlated to the average particular matter (PM) concentrations observed several days before when the contagions occurred (short-term effect), and this correlation is higher for areas [...] Read more.
The conjecture discussed in this paper was that the daily number of certified cases of COVID-19 is direct correlated to the average particular matter (PM) concentrations observed several days before when the contagions occurred (short-term effect), and this correlation is higher for areas with a higher average seasonal PM concentration, as a measure of prolonged exposure to a polluted environment (long-term effect). Furthermore, the correlations between the daily COVID-19 new cases and the mobility trips and those between the daily PM concentrations and mobility trips were also investigated. Correlation analyses were performed for the application case study consisting in 13 of the main Italian cities, through the national air quality and mobility monitoring systems. Data analyses showed that the mobility restrictions performed during the lockdown produced a significant improvement in air quality with an average PM concentrations reduction of about 15%, with maximum variations ranging between 25% and 42%. Estimation results showed a positive correlation (stronger for the more highly polluted cities) between the daily COVID-19 cases and both the daily PM concentrations and mobility trips measured about three weeks before, when probably the contagion occurred. The obtained results are original, and if confirmed in other studies, it would lay the groundwork for the definition of the main context variables which influenced the COVID-19 spread. The findings highlighted in this research also supported by the evidence in the literature and allow concluding that PM concentrations and mobility habits could be considered as potential early indicators of COVID-19 circulation in outdoor environments. However, the obtained results pose significant ethical questions about the proper urban and transportation planning; the most polluted cities have not only worst welfare for their citizens but, as highlighted in this research, could lead to a likely greater spread of current and future respiratory and/or pulmonary health emergencies. The lesson to be learned by this global pandemic will help planners to better preserve the air quality of our cities in the post-COVID-19 era. Full article
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Article
A Comparison of Different Approaches for Assessing Energy Outputs of Combined Heat and Power Geothermal Plants
Sustainability 2021, 13(8), 4527; https://0-doi-org.brum.beds.ac.uk/10.3390/su13084527 - 19 Apr 2021
Abstract
In this paper, we assess using two alternative allocation schemes, namely exergy and primary energy saving (PES) to compare products generated in different combined heat and power (CHP) geothermal systems. In particular, the adequacy and feasibility of the schemes recommended for allocation are [...] Read more.
In this paper, we assess using two alternative allocation schemes, namely exergy and primary energy saving (PES) to compare products generated in different combined heat and power (CHP) geothermal systems. In particular, the adequacy and feasibility of the schemes recommended for allocation are demonstrated by their application to three relevant and significantly different case studies of geothermal CHPs, i.e., (1) Chiusdino in Italy, (2) Altheim in Austria, and (3) Hellisheidi in Iceland. The results showed that, given the generally low temperature level of the cogenerated heat (80–100 °C, usually exploited in district heating), the use of exergy allocation largely marginalizes the importance of the heat byproduct, thus, becoming almost equivalent to electricity for the Chiusdino and Hellisheidi power plants. Therefore, the PES scheme is found to be the more appropriate allocation scheme. Additionally, the exergy scheme is mandatory for allocating power plants’ environmental impacts at a component level in CHP systems. The main drawback of the PES scheme is its country dependency due to the different fuels used, but reasonable and representative values can be achieved based on average EU heat and power generation efficiencies. Full article
(This article belongs to the Special Issue Sustainable Geothermal Energy)
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Article
Adaptive Volt-Var Control Algorithm to Grid Strength and PV Inverter Characteristics
Sustainability 2021, 13(8), 4459; https://0-doi-org.brum.beds.ac.uk/10.3390/su13084459 - 16 Apr 2021
Abstract
The high-penetration of Distributed Energy Resources (DER) in low voltage distribution grids, mainly photovoltaics (PV), might lead to overvoltage in the point of common coupling, thus, limiting the entrance of renewable sources to fulfill the requirements from the network operator. Volt-var is a [...] Read more.
The high-penetration of Distributed Energy Resources (DER) in low voltage distribution grids, mainly photovoltaics (PV), might lead to overvoltage in the point of common coupling, thus, limiting the entrance of renewable sources to fulfill the requirements from the network operator. Volt-var is a common control function for DER power converters that is used to enhance the stability and reliability of the voltage in the distribution system. In this study, a centralized algorithm provides local volt-var control parameters to each PV inverter, which are based on the electrical grid characteristics. Because accurate information of grid characteristics is typically not available, the parametrization of the electrical grid is done using a local power meter data and a voltage sensitivity matrix. The algorithm has different optimization modes that take into account the minimization of voltage deviation and line current. To validate the effectiveness of the algorithm and its deployment in a real infrastructure, the solution has been tested in an experimental setup with PV emulators under laboratory conditions. The volt-var control algorithm successfully adapted its parameters based on grid topology and PV inverter characteristics, achieving a voltage reduction of up to 25% of the allowed voltage deviation. Full article
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Article
Public Norms in Practices of Transitional Planning—The Case of Energy Transition in The Netherlands
Sustainability 2021, 13(8), 4454; https://0-doi-org.brum.beds.ac.uk/10.3390/su13084454 - 16 Apr 2021
Cited by 1
Abstract
The fallibility of intervening in complex realities is widely recognized in planning theory. The prevailing planning approaches of the last two decades may be summarized as attempts to make planning more responsive, corrective, and resilient, and also more sociocratic vis à vis the [...] Read more.
The fallibility of intervening in complex realities is widely recognized in planning theory. The prevailing planning approaches of the last two decades may be summarized as attempts to make planning more responsive, corrective, and resilient, and also more sociocratic vis à vis the traditional government-centric rationalization of planning. These adaptations make sense, yet keep planning within the pragmatic scope of purposive aspirations and pragmatic problem solving. The pivotal statement of the article is that purposive systems run down in complex societies when not adequately sustained by institutionalizing sets of public norms. Public norms fulfil a different function than goal orientation. They provide a normative compass in times of uncertainty and set conditions to social interaction rather than organizing the performance of objectives or solving problems. The article aims to highlight the interrelationships of public norms and pragmatic strategies of planning. Empirically, the article addresses the major turning points of Dutch climate policy concerning the transitions of the electricity market, the major municipal–entrepreneurial initiatives of city-heating, and the decentralization of climate policies. The method of analysis is based on policy analysis of legislation, policy documents, and published contributions to public debates. The results of the analysis highlight the differences between the high policy aspirations and the outcomes. The results give evidence of the wicked problems in the complex energy transition. The discussion questions the mischievousness of ‘good’ planning intentions in complex social figurations, and critically examines the institutionalization of the material norms and the norms of politico-ordinance. The conclusions suggest that the social normalization of public norms in Dutch climate policies is not yet adequately materialized to effectively cope with wicked problems. Full article
Article
Flood Hazard Assessment Mapping in Burned and Urban Areas
Sustainability 2021, 13(8), 4455; https://0-doi-org.brum.beds.ac.uk/10.3390/su13084455 - 16 Apr 2021
Cited by 3
Abstract
This study proposes a simple method to produce a flood hazard assessment map in burned and urban areas, where primary data are scarce. The study area is a municipal unit of Nea Makri, a coastal part of the eastern Attica peninsula (central Greece), [...] Read more.
This study proposes a simple method to produce a flood hazard assessment map in burned and urban areas, where primary data are scarce. The study area is a municipal unit of Nea Makri, a coastal part of the eastern Attica peninsula (central Greece), which has been strongly urbanized and suffered damage from urban fires in 2018. Six factors were considered as the parameters most controlling runoff when it overdraws the drainage system’s capacity. The analytical hierarchy process (AHP) method and a geographical information system (GIS) were utilized to create the flood hazard assessment map. The outcome revealed that the areas with highest flood hazard are distributed in the eastern and southern parts of the study area, as a result of the combination of lowlands with gentle slopes, torrential behavior of the streams, streams covered by construction, increasing urbanization and burned areas. The uncertainty and the verification analyses demonstrate a robust behavior for the model predictions, as well as reliability and accuracy of the map. Comparing the existing urban fabric and road network to the potential flood hazard areas showed that 80% of the urban areas and 50% of the road network were situated within areas prone to flood. The method may be applied to land use planning projects, flood hazard mitigation and post-fire management. Full article
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Article
Improving Energy Efficiency in Buildings Using an Interactive Mathematical Programming Approach
Sustainability 2021, 13(8), 4436; https://0-doi-org.brum.beds.ac.uk/10.3390/su13084436 - 15 Apr 2021
Abstract
Improving energy efficiency in buildings is a major priority and challenge worldwide. The employed measures vary in nature, and the decision analyst, who is typically the architect, the engineer, or the building expert that has undertaken the task to suggest energy efficient solutions, [...] Read more.
Improving energy efficiency in buildings is a major priority and challenge worldwide. The employed measures vary in nature, and the decision analyst, who is typically the architect, the engineer, or the building expert that has undertaken the task to suggest energy efficient solutions, faces a complex decision problem comprising numerous decision variables and multiple, usually competitive objectives. The solution of such multi-objective problems typically involves some sort of objectives aggregation, which reflects the preferences of the involved final decision maker that is the building’s user, occupant, and/or owner. The preferences elicitation, however, is a difficult task, and this paper aims to provide an interactive framework that will allow their consideration in a relatively easy manner. More specifically, a mathematical programming approach is proposed herein, which allows the elicitation and incorporation of the decision maker’s preferences in the decision model via the assessment of his/her utility function with the assistance of the multicriteria decision aid method UTASTAR. To study the feasibility and efficiency of the proposed approach, the case of a simple building is examined as an application example. The study results suggest that the proposed approach is capable of helping the decision analyst to suggest energy measures that satisfy, as much as possible, the decision maker’s preferences, without having to precisely prescribe them beforehand. Full article
(This article belongs to the Special Issue Energy Transition and Climate Change in Decision-making Processes)
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Article
An Approach to the Operation Modes and Strategies for Integrated Hybrid Parabolic Trough and Photovoltaic Solar Systems
Sustainability 2021, 13(8), 4402; https://0-doi-org.brum.beds.ac.uk/10.3390/su13084402 - 15 Apr 2021
Abstract
Concentrated solar power (CSP) and photovoltaic (PV) solar systems can be hybridized, creating synergies: on one hand procuring dispatchability by storing thermal energy, and on the other hand generating electricity at a highly competitive prize. In this paper, we present an approach to [...] Read more.
Concentrated solar power (CSP) and photovoltaic (PV) solar systems can be hybridized, creating synergies: on one hand procuring dispatchability by storing thermal energy, and on the other hand generating electricity at a highly competitive prize. In this paper, we present an approach to the operation strategies and modes for integrated hybrid CSP + PV systems. We focus on parabolic trough (PT) solar plants, especially those operating in the south of Spain. Our study consists in the definition of suitable states for each of the subsystems that constitute a hybrid solar plant. We then propose modes from the combination of suitable states and establish the conditions for the transition between modes depending on the operation strategy. We propose two operation strategies: demand coverage and base load production. The results of this paper can be used in decision making for hybrid solar system simulation programs. Full article
(This article belongs to the Special Issue Solar Power System and Sustainability)
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Article
Aerodynamic Characteristics of Airfoil and Vertical Axis Wind Turbine Employed with Gurney Flaps
Sustainability 2021, 13(8), 4284; https://0-doi-org.brum.beds.ac.uk/10.3390/su13084284 - 12 Apr 2021
Abstract
In the present studies, the effects of Gurney flaps on aerodynamic characteristics of a static airfoil and a rotating vertical axis wind turbine are investigated by means of numerical approaches. First, mesh and time step studies are conducted and the results are validated [...] Read more.
In the present studies, the effects of Gurney flaps on aerodynamic characteristics of a static airfoil and a rotating vertical axis wind turbine are investigated by means of numerical approaches. First, mesh and time step studies are conducted and the results are validated with experimental data in good agreement. The numerical solutions demonstrate that the usage of Gurney flap increases the airfoil lift coefficient CL with a slight increase in drag coefficient CD. Furthermore, mounting a Gurney flap at the trailing edge of the blade increases the power production of the turbine considerably. Increasing the Gurney flap height further increases the power production. The best performance found is obtained for the maximum height used in this study at 6% relative to the chord. This is in contrast to the static airfoil case, which shows no further improvement for a flap height greater than 0.5%c. Increasing the angle of the flap decreases the power production of the turbine slightly but the load fluctuations could be reduced for the small value of the flap height. The present paper demonstrates that the Gurney flap height for high solidity turbines is allowed to be larger than the classical limit of around 2% for lower solidity turbines. Full article
(This article belongs to the Special Issue Consistent Computational Approaches for Wind Energy Applications)
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Article
Energy Transition toward Cleaner Energy Resources in Nepal
Sustainability 2021, 13(8), 4243; https://0-doi-org.brum.beds.ac.uk/10.3390/su13084243 - 11 Apr 2021
Abstract
Energy is an important input for socioeconomic development and human well-being. The rationality of energy transitions toward cleaner energy resources is not only to improve individual living conditions, but also to enhance the economic growth of a nation. Nepal is considered to be [...] Read more.
Energy is an important input for socioeconomic development and human well-being. The rationality of energy transitions toward cleaner energy resources is not only to improve individual living conditions, but also to enhance the economic growth of a nation. Nepal is considered to be one of the countries with a low per-capita electricity use, heavily relying on traditional energy resources such as firewood and agricultural residues. The country is rich in hydropower resources. However, various economic and socioeconomic constraints have left the significant potential for hydroelectricity untapped. This study describes the energy transition patterns in Nepal based on a literature review and field survey of household energy use in the winter. We collected data from 516 households in the Solukhumbu, Panchthar, and Jhapa districts of Nepal. The rate of per-capita electricity consumption was 330 kWh/capita/year, which is significantly lower than that of other contemporary global societies such as India 1000 and China 4900 kWh/capita/year. The increasing trend in hydroelectricity production has optimistically transformed the energy sector toward cleaner resources; this correlates with the GDP per capita. Solar home systems, mini- and micro-hydropower plants, biogas technology, and improved cook stoves have been widely used, which has lowered the health and environmental burdens in rural areas. By analysing the survey data, we found that 25% of the households only relied on traditional cooking fuel, while 67% and 8% of the households relied on mixed and commercial cooking fuels, respectively. Moreover, 77% and 48% of traditional and mixed-fuel-using households were unhappy with current cooking fuels while 40% and 66% of these households preferred to use clean cooking fuels. The share of traditional energy resources decreased from 78% to 68%, while that of commercial energy resources increased from 20% to 28% from 2014/15 to 2019/20. This study suggests that future energy policies and programs should acknowledge the reality of energy transition to achieve sustainability by establishing reliable and clean sources of energy. Full article
(This article belongs to the Special Issue Sustainable Integration of Renewable Power Generation Systems)
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Article
Economizing the Uneconomic: Markets for Reliable, Sustainable, and Price Efficient Electricity
Sustainability 2021, 13(8), 4197; https://0-doi-org.brum.beds.ac.uk/10.3390/su13084197 - 09 Apr 2021
Abstract
Current electricity markets do not efficiently achieve policy targets i.e., sustainability, reliability, and price efficiency. Thus, there are debates on how to achieve these targets by using either market mechanisms e.g., carbon and capacity markets, or non-market mechanisms such as offer-caps, price-caps, and [...] Read more.
Current electricity markets do not efficiently achieve policy targets i.e., sustainability, reliability, and price efficiency. Thus, there are debates on how to achieve these targets by using either market mechanisms e.g., carbon and capacity markets, or non-market mechanisms such as offer-caps, price-caps, and market-monitoring. At the same time, major industry changes including demand response management technologies and large scale batteries bring more elasticity to demand; such changes will impact the methodology needed to achieve the above mentioned targets. This work provides market solutions that capture all three policy targets simultaneously and take into account the above-mentioned industry changes. The proposed solutions are based on: (i) a model of electricity markets that captures all the above mentioned electricity policy targets; (ii) mechanism design and the development of a framework for design of efficient auctions with constraints (individual, joint homogeneous, and joint non-homogeneous). The results show that, within the context of the proposed model, all policy targets can be achieved efficiently by separate capacity and carbon markets in addition to efficient spot markets. The results also highlight that all three policy targets can be achieved without any offer-cap, price-cap, or market monitoring. Thus, within the context of the proposed model, they provide clear answers to the above-mentioned policy debates. Full article
(This article belongs to the Special Issue Renewable Energy Technologies for Sustainable Development)
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Article
Human Dimensions of Urban Blue and Green Infrastructure during a Pandemic. Case Study of Moscow (Russia) and Perth (Australia)
Sustainability 2021, 13(8), 4148; https://0-doi-org.brum.beds.ac.uk/10.3390/su13084148 - 08 Apr 2021
Abstract
Significant challenges of the COVID-19 pandemic highlighted that features of a modern, sustainable and resilient city should not only relate to fulfilling economic and social urban strategies, but also to functional urban design, in particular, related to urban blue and green infrastructure (BGI). [...] Read more.
Significant challenges of the COVID-19 pandemic highlighted that features of a modern, sustainable and resilient city should not only relate to fulfilling economic and social urban strategies, but also to functional urban design, in particular, related to urban blue and green infrastructure (BGI). Using results from a web-based questionnaire survey conducted May–July 2020 in Moscow (Russia) and Perth (Australia), this paper provides insights regarding citizens’ needs for and values of urban BGI as well as their changes during and after the COVID-19 restrictions. Survey data collected during the lockdown period have captured information about people’s ability to access green and blue spaces within urban BGI, inequalities in access, feelings, and values as well as needs and perceived pathways of future development of urban natural environment. In both cities, lockdowns limited access of people to green spaces which affected their mental and physical health. Survey results revealed that the quality, functionality, and location of open green spaces illustrated a disparity in distribution, meaning that in many cases several communities from particular neighborhoods suffered from limited access to BGI. Furthermore, in addition to analyzing perceptions and values of urban nature during the COVID-19 pandemic, some suggestions for improvement of urban BGI based on the survey responses are provided. Full article
(This article belongs to the Special Issue Sustainable Urban Water Landscapes and Blue-Green Infrastructure)
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Article
Cogeneration Supporting the Energy Transition in the Italian Ceramic Tile Industry
Sustainability 2021, 13(7), 4006; https://0-doi-org.brum.beds.ac.uk/10.3390/su13074006 - 03 Apr 2021
Cited by 1
Abstract
Ceramic tile production is an industrial process where energy efficiency management is crucial, given the high amount of energy (electrical and thermal) required by the production cycle. This study presents the preliminary results of a research project aimed at defining the benefits of [...] Read more.
Ceramic tile production is an industrial process where energy efficiency management is crucial, given the high amount of energy (electrical and thermal) required by the production cycle. This study presents the preliminary results of a research project aimed at defining the benefits of using combined heat and power (CHP) systems in the ceramic sector. Data collected from ten CHP installations allowed us to outline the average characteristics of prime movers, and to quantify the contribution of CHP thermal energy supporting the dryer process. The electric size of the installed CHP units resulted in being between 3.4 MW and 4.9 MW, with an average value of 4 MW. Data revealed that when the goal is to maximize the generation of electricity for self-consumption, internal combustion engines are the preferred choice due to higher conversion efficiency. In contrast, gas turbines allowed us to minimize the consumption of natural gas input to the spray dryer. Indeed, the fraction of the dryer thermal demand (between 600–950 kcal/kgH2O), covered by CHP discharged heat, is strictly dependent on the type of prime mover installed: lower values, in the range of 30–45%, are characteristic of combustion engines, whereas the use of gas turbines can contribute up to 77% of the process’s total consumption. Full article
(This article belongs to the Special Issue Industrial Energy Management and Sustainability)
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Article
The Importance of Stud Flanges Size and Shape on the Thermal Performance of Lightweight Steel Framed Walls
Sustainability 2021, 13(7), 3970; https://0-doi-org.brum.beds.ac.uk/10.3390/su13073970 - 02 Apr 2021
Cited by 1
Abstract
Energy production still relies considerably on fossil fuels, and the building sector is a major player in the energy consumption market, mainly for space heating and cooling. Thermal bridges (TBs) in buildings are very relevant for the energy efficiency of buildings and may [...] Read more.
Energy production still relies considerably on fossil fuels, and the building sector is a major player in the energy consumption market, mainly for space heating and cooling. Thermal bridges (TBs) in buildings are very relevant for the energy efficiency of buildings and may have an impact on heating energy needs of up to 30%. Given the high thermal conductivity of steel, the relevance of TBs in lightweight steel framed (LSF) components could be even greater. No research was found in the literature for evaluating how important the size and shape of steel studs are on the thermal performance of LSF building elements, which is the main objective of this work. This assessment is performed for the internal partitions and exterior façade of load-bearing LSF walls. The accuracy of the numerical model used in the simulations was verified and validated by comparison experimental measurements. Three reference steel studs were considered, six stud flange lengths and four steel thicknesses were evaluated, and five flange indentation sizes and four indent filling materials were assessed, corresponding to a total of 246 modelled LSF walls. It was concluded that the R-value decreases when the flange length and the steel studs’ thickness increases, being that these variations are more significant for bigger flange sizes and for thicker steel studs. Additionally, it was found that a small indentation size (2.5 or 5 mm) is enough to provide a significant R-value increase and that it is preferable not to use any flange indentation filling material rather than using a poor performance one (recycled rubber). Full article
(This article belongs to the Special Issue Thermal Behavior and Energy Efficiency of Buildings)
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Article
Aiming Strategy on a Prototype-Scale Solar Receiver: Coupling of Tabu Search, Ray-Tracing and Thermal Models
Sustainability 2021, 13(7), 3920; https://0-doi-org.brum.beds.ac.uk/10.3390/su13073920 - 01 Apr 2021
Abstract
An aiming point strategy applied to a prototype-scale power tower is analyzed in this paper to define the operation conditions and to preserve the lifetime of the solar receiver developed in the framework of the Next-commercial solar power (CSP) H2020 project. This innovative [...] Read more.
An aiming point strategy applied to a prototype-scale power tower is analyzed in this paper to define the operation conditions and to preserve the lifetime of the solar receiver developed in the framework of the Next-commercial solar power (CSP) H2020 project. This innovative solar receiver involves the fluidized particle-in-tube concept. The aiming solution is compared to the case without the aiming strategy. Due to the complex tubular geometry of the receiver, results of the Tabu search for the aiming point strategy are combined with a ray-tracing software, and these results are then coupled with a simplified thermal model of the receiver to evaluate its performance. Daily and hourly aiming strategies are compared, and different objective normalized flux distributions are applied to quantify their influence on the receiver wall temperature distribution, thermal efficiency and particle outlet temperature. A gradual increase in the solar incident power on the receiver is analyzed in order to keep a uniform outlet particle temperature during the start-up. Results show that a tradeoff must be respected between wall temperature and particle outlet temperature. Full article
(This article belongs to the Special Issue Advances in Solar Thermal Energy)
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Article
Improvement of Self-Starting Capabilities of Vertical Axis Wind Turbines with New Design of Turbine Blades
Sustainability 2021, 13(7), 3854; https://0-doi-org.brum.beds.ac.uk/10.3390/su13073854 - 31 Mar 2021
Cited by 1
Abstract
A lift-driven vertical axis wind turbine (VAWT) generates peak power when it is rotating at high tip-speed ratios (TSR), at which time the blades encounter angles of attack (AOA) over a small range from zero to 30 degrees. However, its ability to self-start [...] Read more.
A lift-driven vertical axis wind turbine (VAWT) generates peak power when it is rotating at high tip-speed ratios (TSR), at which time the blades encounter angles of attack (AOA) over a small range from zero to 30 degrees. However, its ability to self-start is dependent upon its performance at low TSRs, at which time the blades encounter a range of AOAs from zero to 180 degrees. A novel vented aerofoil is presented with the intention of improving the performance of a lift-driven VAWT at low TSRs without hampering the performance of the wind turbine at high TSRs. Computational fluid dynamics (CFD) simulation is used to predict the aerodynamic characteristics of a new vented aerofoil based on the well documented NACA0012 profile. Simulations are performed using the SST turbulence model. The results obtained show a reduction in the coefficient of tangential force (the force that generates torque on the wind turbine) at low AOAs (less than 90 degrees) of no more than 30%, while at high AOAs (more than 90 degrees) an improvement in the tangential force of over 100% is observed. Using a simple momentum based performance prediction model, these results suggest that this would lead to an increase in torque generation by a theoretical three-bladed VAWT of up to 20% at low TSRs and a minor reduction in coefficient of performance of up to 9% at TSR of 2 and closer to 1% at higher TSRs. Full article
(This article belongs to the Special Issue Design and Optimization of Renewable Energy Systems)
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Article
Applying PCA to Deep Learning Forecasting Models for Predicting PM2.5
Sustainability 2021, 13(7), 3726; https://0-doi-org.brum.beds.ac.uk/10.3390/su13073726 - 26 Mar 2021
Cited by 3
Abstract
Fine particulate matter (PM2.5) is one of the main air pollution problems that occur in major cities around the world. A country’s PM2.5 can be affected not only by country factors but also by the neighboring country’s air quality factors. [...] Read more.
Fine particulate matter (PM2.5) is one of the main air pollution problems that occur in major cities around the world. A country’s PM2.5 can be affected not only by country factors but also by the neighboring country’s air quality factors. Therefore, forecasting PM2.5 requires collecting data from outside the country as well as from within which is necessary for policies and plans. The data set of many variables with a relatively small number of observations can cause a dimensionality problem and limit the performance of the deep learning model. This study used daily data for five years in predicting PM2.5 concentrations in eight Korean cities through deep learning models. PM2.5 data of China were collected and used as input variables to solve the dimensionality problem using principal components analysis (PCA). The deep learning models used were a recurrent neural network (RNN), long short-term memory (LSTM), and bidirectional LSTM (BiLSTM). The performance of the models with and without PCA was compared using root-mean-square error (RMSE) and mean absolute error (MAE). As a result, the application of PCA in LSTM and BiLSTM, excluding the RNN, showed better performance: decreases of up to 16.6% and 33.3% in RMSE and MAE values. The results indicated that applying PCA in deep learning time series prediction can contribute to practical performance improvements, even with a small number of observations. It also provides a more accurate basis for the establishment of PM2.5 reduction policy in the country. Full article
(This article belongs to the Section Environmental Sustainability and Applications)
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