Sustainability

20 pages, 3581 KiB

Open AccessEditor’s ChoiceArticle

Adaptive Management of Malkumba-Coongie Lakes Ramsar Site in Arid Australia—A Free Flowing River and Wetland System

by Richard T. Kingsford, Craig A. McLoughlin, Robert Brandle, Gilad Bino, Bernie Cockayne, David Schmarr, Travis Gotch, Vol Norris and Justin McCann

Sustainability 2021, 13(6), 3043; https://doi.org/10.3390/su13063043 - 10 Mar 2021

Cited by 6 | Viewed by 5917

Abstract

The Malkumba-Coongie Lakes Ramsar Site has extensive terrestrial and freshwater ecosystems (largest Ramsar Site in Oceania, 2,178,952 ha, designated in 1987), including freshwater and salt lakes, lignum swamps and river channels in central Australia. It is supplied by Cooper Creek, a free-flowing Lake [...] Read more.

The Malkumba-Coongie Lakes Ramsar Site has extensive terrestrial and freshwater ecosystems (largest Ramsar Site in Oceania, 2,178,952 ha, designated in 1987), including freshwater and salt lakes, lignum swamps and river channels in central Australia. It is supplied by Cooper Creek, a free-flowing Lake Eyre Basin river system. The area includes pastoral leases (97% of site grazed, including a regional conservation reserve (35%)) and a National Park (3%), with the largest oil and gas production field in Australia. We developed a Strategic Adaptive Management (SAM) Plan, linking science, monitoring and management of this social-ecological system, involving stakeholders and workshops. This involved developing a shared vision and hierarchy of objectives linked to management actions and identified outputs and outcomes. We exemplify this approach with explicit and measurable end-points (thresholds of potential concern) culminating from low level objectives for fish communities, particularly the alien sleepy cod Oxyeleotris lineolata. We describe this framework, highlighting the benefits in prioritizing management actions and monitoring in collaboration with a diverse range of stakeholders, driving adaptive feedback for learning. The whole approach is aimed at successfully achieving mutually agreed management objectives and the vision to maintain the ecological character of the Malkumba-Coongie Lakes Ramsar Site. Full article

(This article belongs to the Special Issue Durable Protections for Free-Flowing Rivers)

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12 pages, 3269 KiB

Open AccessEditor’s ChoiceArticle

Load Resistance Optimization of a Broadband Bistable Piezoelectric Energy Harvester for Primary Harmonic and Subharmonic Behaviors

by Sungryong Bae and Pilkee Kim

Sustainability 2021, 13(5), 2865; https://doi.org/10.3390/su13052865 - 6 Mar 2021

Cited by 6 | Viewed by 2572

Abstract

In this study, optimization of the external load resistance of a piezoelectric bistable energy harvester was performed for primary harmonic (period-1T) and subharmonic (period-3T) interwell motions. The analytical expression of the optimal load resistance was derived, based on the spectral analyses of the [...] Read more.

In this study, optimization of the external load resistance of a piezoelectric bistable energy harvester was performed for primary harmonic (period-1T) and subharmonic (period-3T) interwell motions. The analytical expression of the optimal load resistance was derived, based on the spectral analyses of the interwell motions, and evaluated. The analytical results are in excellent agreement with the numerical ones. A parametric study shows that the optimal load resistance depended on the forcing frequency, but not the intensity of the ambient vibration. Additionally, it was found that the optimal resistance for the period-3T interwell motion tended to be approximately three times larger than that for the period-1T interwell motion, which means that the optimal resistance was directly affected by the oscillation frequency (or oscillation period) of the motion rather than the forcing frequency. For broadband energy harvesting applications, the subharmonic interwell motion is also useful, in addition to the primary harmonic interwell motion. In designing such piezoelectric bistable energy harvesters, the frequency dependency of the optimal load resistance should be considered properly depending on ambient vibrations. Full article

(This article belongs to the Section Energy Sustainability)

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16 pages, 2320 KiB

Open AccessEditor’s ChoiceArticle

The Sustainability of Thailand’s Protected-Area System under Climate Change

by Nirunrut Pomoim, Robert J. Zomer, Alice C. Hughes and Richard T. Corlett

Sustainability 2021, 13(5), 2868; https://doi.org/10.3390/su13052868 - 6 Mar 2021

Cited by 11 | Viewed by 4138

Abstract

Protected areas are the backbone of biodiversity conservation but vulnerable to climate change. Thailand has a large and well-planned protected area system, covering most remaining natural vegetation. A statistically derived global environmental stratification (GEnS) was used to predict changes in bioclimatic conditions across [...] Read more.

Protected areas are the backbone of biodiversity conservation but vulnerable to climate change. Thailand has a large and well-planned protected area system, covering most remaining natural vegetation. A statistically derived global environmental stratification (GEnS) was used to predict changes in bioclimatic conditions across the protected area system for 2050 and 2070, based on projections from three CMIP5 earth system models and two representative concentration pathways (RCPs). Five bioclimatic zones were identified composed of 28 strata. Substantial spatial reorganization of bioclimates is projected in the next 50 years, even under RCP2.6, while under RCP8.5 the average upward shift for all zones by 2070 is 328–483 m and the coolest zone disappears with two models. Overall, 7.9–31.0% of Thailand’s land area will change zone by 2070, and 31.7–90.2% will change stratum. The consequences for biodiversity are less clear, particularly in the lowlands where the existing vegetation mosaic is determined largely by factors other than climate. Increasing connectivity of protected areas along temperature and rainfall gradients would allow species to migrate in response to climate change, but this will be difficult in much of Thailand. For isolated protected areas and species that cannot move fast enough, more active, species-specific interventions may be necessary. Full article

(This article belongs to the Section Air, Climate Change and Sustainability)

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23 pages, 1523 KiB

Open AccessEditor’s ChoiceArticle

The Constrained Air Transport Energy Paradigm in 2021

by Abel Jiménez-Crisóstomo, Luis Rubio-Andrada, María Soledad Celemín-Pedroche and María Escat-Cortés

Sustainability 2021, 13(5), 2830; https://doi.org/10.3390/su13052830 - 5 Mar 2021

Cited by 7 | Viewed by 4275

Abstract

The increasing relevance of air transport as a contributor to climate change requires the development of emissions reduction technologies in a socio-economic and cultural context, where demand and air traffic have traditionally held sustained growth rates. However, the irruption of COVID-19 in 2020 [...] Read more.

The increasing relevance of air transport as a contributor to climate change requires the development of emissions reduction technologies in a socio-economic and cultural context, where demand and air traffic have traditionally held sustained growth rates. However, the irruption of COVID-19 in 2020 has had an enormous negative impact on air travel demand and traffic volumes. Coincidentally, during 2020, new technology proposals for emissions reduction based on use of hydrogen and synthetic fuels have emerged from the aviation stake holders. By following a novel approach connecting the analysis of expectations of technology developments and their deployment into the fleet to market constraints, this study discusses how, even considering the new technology proposals and even if the COVID-19 has led to a completely different scenario in tourism and aviation, the air transport energy paradigm will remain unchanged in the upcoming decades as a consequence of market constraints, aircraft complexity, compliance with safety requirements, and extended life cycles. In this frame, aviation needs to keep on pursuing the abatement of its emissions while managing social expectations in a realistic manner and leaning on compensation schemes to achieve emissions contention while new technologies become serviceable in the longer term. Full article

(This article belongs to the Special Issue The Future of Sustainable Mobility Air Transport Systems: Challenges and Approaches)

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19 pages, 3403 KiB

Open AccessEditor’s ChoiceArticle

Sustainability Assessment of Intensified Forestry—Forest Bioenergy versus Forest Biodiversity Targeting Forest Birds

by Ulla Mörtberg, Xi-Lillian Pang, Rimgaudas Treinys, Renats Trubins and Gintautas Mozgeris

Sustainability 2021, 13(5), 2789; https://doi.org/10.3390/su13052789 - 4 Mar 2021

Cited by 5 | Viewed by 3117

Abstract

Intensified forestry can be seen as a solution to climate change mitigation and securing energy supply, increasing the production of forest bioenergy feedstock as a substitution for fossil fuels. However, it may come with detrimental impacts on forest biodiversity, especially related to older [...] Read more.

Intensified forestry can be seen as a solution to climate change mitigation and securing energy supply, increasing the production of forest bioenergy feedstock as a substitution for fossil fuels. However, it may come with detrimental impacts on forest biodiversity, especially related to older forests. The aim of this study was to assess the sustainability of intensified forestry from climate-energy and biodiversity perspectives, targeting forest bird species. For this purpose, we applied the Landscape simulation and Ecological Assessment (LEcA) tool to the study area of Lithuania, having high ambitions for renewables and high forest biodiversity. With LEcA, we simulated forest growth and management for 100 years with two forest management strategies: Business As Usual (BAU) and Intensive forestry (INT), the latter with the purpose to fulfil renewable energy goals. With both strategies, the biomass yields increased well above the yields of the reference year, while the biodiversity indicators related to forest bird habitat to different degrees show the opposite, with lower levels than for the reference year. Furthermore, Strategy INT resulted in small-to-no benefits in the long run concerning potential biomass harvesting, while substantially affecting the biodiversity indicators negatively. The model results have the potential to inform policy and forest management planning concerning several sustainability goals simultaneously. Full article

(This article belongs to the Special Issue Integrated Sustainability Assessment of Forest Bioenergy Options)

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17 pages, 3915 KiB

Open AccessEditor’s ChoiceArticle

Implementation of a Stable Solar-Powered Microgrid Testbed for Remote Applications

by Hossein Saberi, Hamidreza Nazaripouya and Shahab Mehraeen

Sustainability 2021, 13(5), 2707; https://doi.org/10.3390/su13052707 - 3 Mar 2021

Cited by 3 | Viewed by 2065

Abstract

An intrinsically stable microgrid, operated by inverter-interfaced distributed energy resources (I-DERs) is introduced in this paper. The microgrid is built upon a systematic design method, which is adapted from the operation of the synchronous machine (SM). The proposed method analogizes the dynamics of [...] Read more.

An intrinsically stable microgrid, operated by inverter-interfaced distributed energy resources (I-DERs) is introduced in this paper. The microgrid is built upon a systematic design method, which is adapted from the operation of the synchronous machine (SM). The proposed method analogizes the dynamics of the dc-link in I-DERs to the rotor dynamics in synchronous generators (SGs) and utilizes the capacitor as energy storage. Thus, the proposed mechanism relaxes battery usage for frequency control, and by using the capacitive stored energy, provides a high fault ride-through capability, which is suitable for both on-grid and off-grid applications. Based on stability analysis of the SG and the dynamic state matrix eigenvalues for multimachine power system, the dc-link capacitor of I-DERs is characterized in the context of microgrid. The dc-link capacitor stores kinetic energy similar to the rotor of the SG and provides inertia in transients without the need of battery storage. The inverter angle responds to the change of the dc link voltage (energy). The dc-link voltage is then controlled similar to the field control pertaining to the SG. Finally, a governor-like mechanism is applied to maintain dc-link voltage stability. Simulation and experimental results are provided to show the effectiveness of the proposed design mechanisms. Full article

(This article belongs to the Special Issue Innovative Solutions for Integration of Distributed Energy Resources)

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20 pages, 7731 KiB

Open AccessEditor’s ChoiceArticle

Climate-Responsive Green-Space Design Inspired by Traditional Gardens: Microclimate and Human Thermal Comfort of Japanese Gardens

by Lihua Cui, Christoph D. D. Rupprecht and Shozo Shibata

Sustainability 2021, 13(5), 2736; https://doi.org/10.3390/su13052736 - 3 Mar 2021

Cited by 14 | Viewed by 5207

Abstract

Urban green spaces can provide relaxation, exercise, social interaction, and many other benefits for their communities, towns, and cities. However, green spaces in hot and humid regions risk being underutilized by residents unless thermal environments are designed to be sufficiently comfortable. Understanding what [...] Read more.

Urban green spaces can provide relaxation, exercise, social interaction, and many other benefits for their communities, towns, and cities. However, green spaces in hot and humid regions risk being underutilized by residents unless thermal environments are designed to be sufficiently comfortable. Understanding what conditions are needed for comfortable outdoor spaces, particularly how people feel in regard to their thermal environment, is vital in designing spaces for public use. Traditional gardens are excellent examples of successful microclimate design from which we can learn, as they are developed over the generations through observation and modification. This study analyzed how Japanese gardens affect people’s thermal stress on extremely hot summer days. Meteorological data was collected in three Japanese gardens, and human thermal comfort was evaluated through physiological equivalent temperature (PET). Statistical analysis examined the relationship between spatial configurations of the gardens and thermal comfort. Our study revealed that Japanese gardens can efficiently ameliorate thermal stress. Spatial analysis showed that garden elements affect thermal comfort variously depending on time of the day and spatial distribution. Full article

(This article belongs to the Special Issue Urban Green Infrastructure (UGI): Biodiversity, Ecosystem Services and Human Well-Being)

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15 pages, 705 KiB

Open AccessEditor’s ChoiceArticle

An Integrated Approach of Multi-Criteria Decision-Making and Grey Theory for Evaluating Urban Public Transportation Systems

by Ahmad Alkharabsheh, Sarbast Moslem, Laila Oubahman and Szabolcs Duleba

Sustainability 2021, 13(5), 2740; https://doi.org/10.3390/su13052740 - 3 Mar 2021

Cited by 59 | Viewed by 6006

Abstract

Improving the local urban transport system’s quality is often seen as one of the critical points for the government and the local operator. An amelioration of the system can improve users’ satisfaction and attract new users while simultaneously decreasing traffic congestion and pollution. [...] Read more.

Improving the local urban transport system’s quality is often seen as one of the critical points for the government and the local operator. An amelioration of the system can improve users’ satisfaction and attract new users while simultaneously decreasing traffic congestion and pollution. Efficient methodologies are required to achieve sustainable development regarding complex issues associated with traffic congestion and pollution. In this study, we propose using the analytic hierarchy process (AHP) grey values to overcome the limitations of the uncertainty in the classical AHP approach. The presented grey-AHP model assumes an efficient contrivance to facilitate the public transport system’s supply quality evaluation, especially when respondents are non-experts. Finally, we estimate and rank the public transport system’s supply quality criteria by adopting the proposed model for a real-world case study (Amman city, Jordan). The study’s outcome shows the effectiveness and the applicability of the developed approach for enhancing the quality of the public transport system. Full article

(This article belongs to the Collection Sustainability in Urban Transportation Planning)

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19 pages, 827 KiB

Open AccessEditor’s ChoiceArticle

Adopting Multiactor Multicriteria Analysis for the Evaluation of Energy Scenarios

by Sebastian Schär and Jutta Geldermann

Sustainability 2021, 13(5), 2594; https://doi.org/10.3390/su13052594 - 1 Mar 2021

Cited by 14 | Viewed by 3652

Abstract

The assessment of future options and pathways for sustainable energy systems requires considering multiple techno-economic, ecological and social issues. Multicriteria analysis methods, which are useful tools that aid decision processes involving various and even conflicting qualitative and quantitative criteria, could support such comprehensive [...] Read more.

The assessment of future options and pathways for sustainable energy systems requires considering multiple techno-economic, ecological and social issues. Multicriteria analysis methods, which are useful tools that aid decision processes involving various and even conflicting qualitative and quantitative criteria, could support such comprehensive analyses. With regard to energy policies, the key actors and stakeholders’ acceptance of emerging and innovative technologies for generating, converting and storing electricity, heat and fuels is crucial for their future implementation. The multiactor multicriteria (MAMCA) methodology was developed to involve stakeholders with vastly different views and objectives when addressing complex societal problems. We extend the MAMCA methodology to include the outranking approach PROMETHEE, which allows us to explicitly consider the stakeholders’ objectives in the evaluation process. The MAMCA method with PROMETHEE is applied to a case study of four different transition pathways of providing electricity to a bioenergy village in Germany. The explicit mapping at hand of an illustrative case study could help researchers and decision makers greatly in the assessment of pathways for sustainable energy systems; it is also applicable in other contexts requiring extensive stakeholder involvement and where qualitative and quantitative criteria are to be considered simultaneously. The detailed sensitivity analysis provided by the extension of the MAMCA method with PROMETHEE not only reveals the stakeholders’ crucial trade-offs when allowing each stakeholder group to develop its own set of criteria and weights but also indicates compromise options. Full article

(This article belongs to the Special Issue Analyzing Development Paths of Emerging Energy Technologies)

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20 pages, 1997 KiB

Open AccessEditor’s ChoiceArticle

Social Sustainability of Compact Neighbourhoods Evidence from London and Berlin

by M. Reza Shirazi and Ramin Keivani

Sustainability 2021, 13(4), 2340; https://doi.org/10.3390/su13042340 - 22 Feb 2021

Cited by 24 | Viewed by 5755

Abstract

This article revisits social sustainability of compact urban neighbourhoods based on first-hand evidence from four case studies in London and Berlin. It suggests a working definition for socially sustainable neighbourhoods, develops a tripartite integrative evaluation framework for measuring social sustainability of urban neighbourhoods, [...] Read more.

This article revisits social sustainability of compact urban neighbourhoods based on first-hand evidence from four case studies in London and Berlin. It suggests a working definition for socially sustainable neighbourhoods, develops a tripartite integrative evaluation framework for measuring social sustainability of urban neighbourhoods, and applies it to four case studies in London and Berlin. Findings of this research are in line with some dominant arguments made in favour of social sustainability of compact urban form, but challenges some others. Research findings suggest that compact urban form is not an urban orthodoxy, but has multiple and contrasting social meanings and perceptions in different contexts and places. Full article

(This article belongs to the Collection Social Sustainability and New Urban Residential Spaces)

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23 pages, 7866 KiB

Open AccessEditor’s ChoiceArticle

Global Analysis of Durable Policies for Free-Flowing River Protections

by Denielle Perry, Ian Harrison, Stephannie Fernandes, Sarah Burnham and Alana Nichols

Sustainability 2021, 13(4), 2347; https://doi.org/10.3390/su13042347 - 22 Feb 2021

Cited by 27 | Viewed by 8528

Abstract

Freshwater ecosystems are poorly represented in global networks of protected areas. This situation underscores an urgent need for the creation, application, and expansion of durable (long-term and enforceable) protection mechanisms for free-flowing rivers that go beyond conventional protected area planning. To address this [...] Read more.

Freshwater ecosystems are poorly represented in global networks of protected areas. This situation underscores an urgent need for the creation, application, and expansion of durable (long-term and enforceable) protection mechanisms for free-flowing rivers that go beyond conventional protected area planning. To address this need, we must first understand where and what types of protections exist that explicitly maintain the free-flowing integrity of rivers, as well as the efficacy of such policy types. Through policy analysis and an in-depth literature review, our study identifies three main policy mechanisms used for such protections: (1) River Conservation Systems; (2) Executive Decrees and Laws; and (3) Rights of Rivers. We found that globally only eight counties have national river conservation systems while seven countries have used executive decrees and similar policies to halt dam construction, and Rights of Rivers movements are quickly growing in importance, relative to other protection types. Despite the current extent of protection policies being insufficient to tackle the freshwater and biodiversity crises facing the world’s rivers, they do provide useful frameworks to guide the creation and expansion of protections. Ultimately, as countries act on global calls for protections, policy mechanisms must be tailored to their individual social and ecological geographies. Full article

(This article belongs to the Special Issue Durable Protections for Free-Flowing Rivers)

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25 pages, 4041 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Assessment of Mechanical Properties and Structural Morphology of Alkali-Activated Mortars with Industrial Waste Materials

by Iman Faridmehr, Chiara Bedon, Ghasan Fahim Huseien, Mehdi Nikoo and Mohammad Hajmohammadian Baghban

Sustainability 2021, 13(4), 2062; https://doi.org/10.3390/su13042062 - 14 Feb 2021

Cited by 22 | Viewed by 3752

Abstract

Alkali-activated products composed of industrial waste materials have shown promising environmentally friendly features with appropriate strength and durability. This study explores the mechanical properties and structural morphology of ternary blended alkali-activated mortars composed of industrial waste materials, including fly ash (FA), palm oil [...] Read more.

Alkali-activated products composed of industrial waste materials have shown promising environmentally friendly features with appropriate strength and durability. This study explores the mechanical properties and structural morphology of ternary blended alkali-activated mortars composed of industrial waste materials, including fly ash (FA), palm oil fly ash (POFA), waste ceramic powder (WCP), and granulated blast-furnace slag (GBFS). The effect on the mechanical properties of the Al₂O₃, SiO₂, and CaO content of each binder is investigated in 42 engineered alkali-activated mixes (AAMs). The AAMs structural morphology is first explored with the aid of X-ray diffraction, scanning electron microscopy, and Fourier-transform infrared spectroscopy measurements. Furthermore, three different algorithms are used to predict the AAMs mechanical properties. Both an optimized artificial neural network (ANN) combined with a metaheuristic Krill Herd algorithm (KHA-ANN) and an ANN-combined genetic algorithm (GA-ANN) are developed and compared with a multiple linear regression (MLR) model. The structural morphology tests confirm that the high GBFS volume in AAMs results in a high volume of hydration products and significantly improves the final mechanical properties. However, increasing POFA and WCP percentage in AAMs manifests in the rise of unreacted silicate and reduces C-S-H products that negatively affect the observed mechanical properties. Meanwhile, the mechanical features in AAMs with high-volume FA are significantly dependent on the GBFS percentage in the binder mass. It is also shown that the proposed KHA-ANN model offers satisfactory results of mechanical property predictions for AAMs, with higher accuracy than the GA-ANN or MLR methods. The final weight and bias values given by the model suggest that the KHA-ANN method can be efficiently used to design AAMs with targeted mechanical features and desired amounts of waste consumption. Full article

(This article belongs to the Special Issue Sustainable Structural Design for High-Performance Buildings and Infrastructures)

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11 pages, 1680 KiB

Open AccessEditor’s ChoiceReview

Up-To-Date Challenges for the Conservation, Rehabilitation and Energy Retrofitting of Higher Education Cultural Heritage Buildings

by Luisa Dias Pereira, Vanessa Tavares and Nelson Soares

Sustainability 2021, 13(4), 2061; https://doi.org/10.3390/su13042061 - 14 Feb 2021

Cited by 41 | Viewed by 8988

Abstract

In higher-education world heritage sites, the conservation and energy retrofitting of heritage buildings (HBs) is an important vector for their development, competitiveness and welfare. To guarantee their ongoing use, these buildings must be adapted to face current and emerging societal challenges: (i) the [...] Read more.

In higher-education world heritage sites, the conservation and energy retrofitting of heritage buildings (HBs) is an important vector for their development, competitiveness and welfare. To guarantee their ongoing use, these buildings must be adapted to face current and emerging societal challenges: (i) the conservation of cultural heritage and the maintenance of their original characteristics and identity; (ii) the transformation of heritage sites into tourist centers that energize the local economy, generating revenue and jobs; (iii) the adaptation of the buildings to new uses and functions that demand energy retrofitting strategies to satisfy today’s standards of thermal comfort, indoor environmental quality (IEQ) and energy efficiency; (iv) tackling impacts of climate change, particularly global warming and extreme weather events; and finally, (v) the implementation of strategies to mitigate the impact of a growing number of tourists. The combined implications of these challenges require a comprehensive approach with interrelated measures strongly reliant on the use of technology and innovation. This work aims to discuss how higher-education cultural HBs can be rethought to serve these expectations. Moreover, a multidisciplinary intervention framework is provided to discuss how HBs can respond to the challenges and risks of rehabilitation, energy retrofitting, climate change and increasing tourism. Full article

(This article belongs to the Special Issue Thermal Behavior and Energy Efficiency of Buildings)

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23 pages, 20806 KiB

Open AccessEditor’s ChoiceArticle

LCA and Exergo-Environmental Evaluation of a Combined Heat and Power Double-Flash Geothermal Power Plant

by Vitantonio Colucci, Giampaolo Manfrida, Barbara Mendecka, Lorenzo Talluri and Claudio Zuffi

Sustainability 2021, 13(4), 1935; https://doi.org/10.3390/su13041935 - 11 Feb 2021

Cited by 23 | Viewed by 4729

Abstract

This study deals with the life cycle assessment (LCA) and an exergo-environmental analysis (EEvA) of the geothermal Power Plant of Hellisheiði (Iceland), a combined heat and power double flash plant, with an installed power of 303.3 MW for electricity and 133 MW for [...] Read more.

This study deals with the life cycle assessment (LCA) and an exergo-environmental analysis (EEvA) of the geothermal Power Plant of Hellisheiði (Iceland), a combined heat and power double flash plant, with an installed power of 303.3 MW for electricity and 133 MW for hot water. LCA approach is used to evaluate and analyse the environmental performance at the power plant global level. A more in-depth study is developed, at the power plant components level, through EEvA. The analysis employs existing published data with a realignment of the inventory to the latest data resource and compares the life cycle impacts of three methods (ILCD 2011 Midpoint, ReCiPe 2016 Midpoint-Endpoint, and CML-IA Baseline) for two different scenarios. In scenario 1, any emission abatement system is considered. In scenario 2, re-injection of CO₂ and H₂S is accounted for. The analysis identifies some major hot spots for the environmental power plant impacts, like acidification, particulate matter formation, ecosystem, and human toxicity, mainly caused by some specific sources. Finally, an exergo-environmental analysis allows indicating the wells as significant contributors of the environmental impact rate associated with the construction, Operation & Maintenance, and end of life stages and the HP condenser as the component with the highest environmental cost rate. Full article

(This article belongs to the Special Issue Sustainability of Geothermal Energy Conversion—Life Cycle Analysis)

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24 pages, 7780 KiB

Open AccessEditor’s ChoiceArticle

Innovative Renewable Technology Integration for Nearly Zero-Energy Buildings within the Re-COGNITION Project

by Giulia Mancò, Elisa Guelpa, Alessandro Colangelo, Alessandro Virtuani, Tommaso Morbiato and Vittorio Verda

Sustainability 2021, 13(4), 1938; https://doi.org/10.3390/su13041938 - 11 Feb 2021

Cited by 18 | Viewed by 4152

Abstract

With the 2010/31/EU directive, all new buildings shall be nearly zero-energy buildings (nZEB) from 2020 onward, with the aim of strongly reducing the energy consumption related to the building sector. To achieve this goal, it is not sufficient to focus on the design [...] Read more.

With the 2010/31/EU directive, all new buildings shall be nearly zero-energy buildings (nZEB) from 2020 onward, with the aim of strongly reducing the energy consumption related to the building sector. To achieve this goal, it is not sufficient to focus on the design of the building envelope; smart and efficient energy management is necessary. Moreover, to ensure the adoption of RES systems in the built environment, innovative technologies need to be further developed in order to increase their cost-effectiveness, energy efficiency and integration capability. This paper proposes a synthesis, design and operation optimization of an integrated multi-energy system composed of traditional and innovative renewable technologies, developed within the European project Re-COGNITION. A biogas-based micro cogeneration unit, lightweight glass-free photovoltaic modules, a passive variable geometry small wind turbine optimized for an urban environment and latent heat thermal storage based on phase change materials are some of the technologies developed within the Re-COGNITION project. The optimization problem is solved to contemporarily evaluate (a) the optimal design and (b) the optimal operations of the set of technologies considering both investment and operating costs, using mixed integer non-linear programming. The optimization is applied to the four pilots that are developed during the project, in various European cities (Turin (Italy), Corby (United Kingdom), Thessaloniki (Greece), Cluj-Napoca (Romania). Simulation results show that the development and optimal exploitation of new technologies through optimization strategies provide significant benefits in terms of cost (between 11% and 42%) and emissions (between 10% and 25%), managing building import/export energy and charge/discharge storage cycles. Full article

(This article belongs to the Special Issue Thermal Energy Storage, District Heating and Optimization in a Multi Energy System Context)

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18 pages, 4052 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Alkaline Fractionation and Subsequent Production of Nano-Structured Silica and Cellulose Nano-Fibrils for the Comprehensive Utilization of Rice Husk

by Hyun Jin Jung, Hyun Kwak, Jinyoung Chun and Kyeong Keun Oh

Sustainability 2021, 13(4), 1951; https://doi.org/10.3390/su13041951 - 11 Feb 2021

Cited by 10 | Viewed by 2984

Abstract

The parameters of the alkaline fractionation process were investigated and optimized using a statistical analysis method to simultaneously remove hemicellulose and ash from rice husk (RH) concomitantly. After the alkaline fractionation process, the residual solid contained high cellulose, and the recovery yield of [...] Read more.

The parameters of the alkaline fractionation process were investigated and optimized using a statistical analysis method to simultaneously remove hemicellulose and ash from rice husk (RH) concomitantly. After the alkaline fractionation process, the residual solid contained high cellulose, and the recovery yield of hemicellulose was enhanced in the fractionated liquid hydrolyzate. The hemicellulosic sugar recovery yield (71.6%), de-ashing yield (>99%), and lignin removal (>80%) were obtained at the reaction conditions of 150 °C of temperature, 40 min of reaction time, and 6% (w/v) of NaOH concentration. Subsequently, nano-structured silica was synthesized using black liquor obtained as a by-product of this fractionation process. For the production of nano-structured silica, it was observed that the pH of a black liquor and the heat treatment temperature significantly influenced the textural properties of silica product. In addition, the two-stage bleaching of solid residue followed by colloid milling for the production of high value-added CNF with was attempted. As a result, in addition to 119 g of fermentable sugar, 143 g of high-purity (>98%) silica with a surface area of 328 m²g⁻¹ and 273.1 g of high-functional CNF with cellulose content of 80.1% were simultaneously obtained from 1000 g of RH. Full article

(This article belongs to the Special Issue Valorization of Residues from Energy Conversion of Biomass for Advanced and Sustainable Material Applications)

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17 pages, 1546 KiB

Open AccessEditor’s ChoiceReview

Water-Energy-Food Nexus: Critical Review, Practical Applications, and Prospects for Future Research

by Aries Purwanto, Janez Sušnik, Franciscus X. Suryadi and Charlotte de Fraiture

Sustainability 2021, 13(4), 1919; https://doi.org/10.3390/su13041919 - 10 Feb 2021

Cited by 76 | Viewed by 12909

Abstract

This paper presents knowledge gaps and critiques on the water–energy–food (WEF) nexus that have emerged since the concept of the WEF nexus was proposed by the World Economic Forum and the Bonn 2011 Conference. Furthermore, this study analyses current innovations on the WEF [...] Read more.

This paper presents knowledge gaps and critiques on the water–energy–food (WEF) nexus that have emerged since the concept of the WEF nexus was proposed by the World Economic Forum and the Bonn 2011 Conference. Furthermore, this study analyses current innovations on the WEF nexus concept, applications, and impacts during the period of 2012–2020. This begins by reviewing ten WEF nexus frameworks developed by international organizations and researchers. On this basis, several gaps and omissions in nexus frameworks are obvious in almost all developed frameworks. Studies that start to address some of these gaps are analysed, but they are relatively few and do not address all gaps. Several proposed improvements to nexus frameworks are identified to narrow the gaps and put the concept into practical implementation in WEF resources management and governance. Four principles and the perspective of “from local to global” for future WEF nexus framework development and analysis are suggested to ensure that the security of water, energy, and food resources can be achieved sustainably in local communities. This will improve the impact of national and global ambitions on WEF security. Full article

(This article belongs to the Section Energy Sustainability)

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30 pages, 4305 KiB

Open AccessEditor’s ChoiceArticle

Optimized Physical Properties of Electrochromic Smart Windows to Reduce Cooling and Heating Loads of Office Buildings

by Jae-Hyang Kim, Jongin Hong and Seung-Hoon Han

Sustainability 2021, 13(4), 1815; https://doi.org/10.3390/su13041815 - 8 Feb 2021

Cited by 14 | Viewed by 3522

Abstract

The concept of smart windows that can change the properties of windows and doors in response to external stimuli has recently been introduced. Smart windows provide superior energy savings and control of indoor environments. This concept can advance sustainable architecture, and it will [...] Read more.

The concept of smart windows that can change the properties of windows and doors in response to external stimuli has recently been introduced. Smart windows provide superior energy savings and control of indoor environments. This concept can advance sustainable architecture, and it will make it possible to connect with the fourth industry, which has developed recently. However, unlike the relevant hardware, is advancing rapidly, research on methods of adjusting smart windows is slow. Therefore, in this study, an analysis of energy use over time was conducted on electrochromic windows, one of the main types of smart windows. Through this analysis, the optimal properties of electrochromic smart windows were identified, and an operation schedule was created. In addition, energy saving rates were derived through a comparison with existing architectural windows. Full article

(This article belongs to the Special Issue Sustainable Conversion of Renewable Energy Sources)

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15 pages, 4175 KiB

Open AccessEditor’s ChoiceArticle

Quantitative Assessment of Energy Supply Security: Korea Case Study

by Herie Park and Sungwoo Bae

Sustainability 2021, 13(4), 1854; https://doi.org/10.3390/su13041854 - 8 Feb 2021

Cited by 14 | Viewed by 4821

Abstract

Ensuring energy supply security has become one of the most important purposes for many countries. To make the strategies for ensuring the energy supply security of a country, it is essential to quantitatively assess the security. This paper aims to present a methodology [...] Read more.

Ensuring energy supply security has become one of the most important purposes for many countries. To make the strategies for ensuring the energy supply security of a country, it is essential to quantitatively assess the security. This paper aims to present a methodology to evaluate the energy supply security of a country by using different indices of energy dependence and energy diversity, which have been raised as two main paradigms of energy supply security. This study also proposes two indices reflecting the correlation between a country’s energy diversity and energy import dependence to evaluate its energy supply security based on easily accessible data. The presented methodology and indices were applied to the evaluation of the primary energy supply security of Korea from 1991 to 2018. The results show that a country highly dependent on energy imports is not evaluated as secure enough in terms of energy supply even if it obtains higher energy diversity. This finding supports the importance of the correlation of energy dependence and energy diversity of a country to ensure its energy supply security. This approach could be further adapted to other countries and help them to make their energy policy and strategies. Full article

(This article belongs to the Collection Secure and Sustainable Energy System)

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18 pages, 2080 KiB

Open AccessEditor’s ChoiceArticle

Application of Multi-Actor Multi-Criteria Analysis for Transition Management in Energy Communities

by Maria Luisa Lode, Geert te Boveldt, Cathy Macharis and Thierry Coosemans

Sustainability 2021, 13(4), 1783; https://doi.org/10.3390/su13041783 - 7 Feb 2021

Cited by 18 | Viewed by 5620

Abstract

Energy communities (ECs) play a role in the transition towards a low-carbon economy by 2050 and receive increasing attention from stakeholders within the energy sector. To foster ECs, transition management (TM) is a promising managerial approach to steer and guide the transition towards [...] Read more.

Energy communities (ECs) play a role in the transition towards a low-carbon economy by 2050 and receive increasing attention from stakeholders within the energy sector. To foster ECs, transition management (TM) is a promising managerial approach to steer and guide the transition towards more sustainable practices. However, TM lacks a consistent methodology that addresses the criticism of the current application. To investigate what a structured and replicable TM approach for ECs can look like, this paper applies the multi-actor multi-criteria analysis (MAMCA), a participative multi-criteria decision method, to a case study EC in the Netherlands involving various stakeholders. The impact of the application on power relations, the political sphere, sustainability conceptualization, guidance of transitions, and representation was analyzed. MAMCA was found useful for multi-stakeholder settings seen in potential ECs, offering a unifying methodology for the practical application of TM. In the EC setting, the added value of MAMCA within TM lies more in the social representation, insight into stakeholder viewpoints, and communication rather than in final decision-making. Full article

(This article belongs to the Special Issue Energy Communities in the Changing Energy Landscape)

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16 pages, 5146 KiB

Open AccessEditor’s ChoiceArticle

Analysis of PV Self-Consumption in Educational and Office Buildings in Spain

by Ángel José Ordóñez Mendieta and Esteban Sánchez Hernández

Sustainability 2021, 13(4), 1662; https://doi.org/10.3390/su13041662 - 4 Feb 2021

Cited by 12 | Viewed by 3570

Abstract

As grid parity is reached in many countries, photovoltaic self-consumption is raising great interest. Currently, there is a big number of new projects being developed in Spain thanks to the new regulation. From the experience of the monitoring of one full year of [...] Read more.

As grid parity is reached in many countries, photovoltaic self-consumption is raising great interest. Currently, there is a big number of new projects being developed in Spain thanks to the new regulation. From the experience of the monitoring of one full year of operation of a self-consumption PV plant in a university building, a regulatory, energy, and economic analysis is made for this type of building. It has been carried out by simulating the behavior of the building with installations within the range of PV powers allowed in the Spanish regulation. The analysis shows the good fitting between the new Royal Decree of Self-Consumption and the new Building Code. The economic analysis proves that the new simplified compensation method gives the best economic return for this use of the buildings when the PV production is matched with the consumption. The time of return of investment is between 8 and 9 years, and the levelized cost of electricity (LCOE) is into the range of the pool market price of electricity. These results show the profitability of PV self-consumption for this type of building. Full article

(This article belongs to the Collection Smart Energy for a Sustainable Future. Experiences in Photovoltaic System Monitoring)

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21 pages, 411 KiB

Open AccessEditor’s ChoiceArticle

Crop Wild Relatives (CWR) Priority in Italy: Distribution, Ecology, In Situ and Ex Situ Conservation and Expected Actions

by Enrico Vito Perrino and Robert Philipp Wagensommer

Sustainability 2021, 13(4), 1682; https://doi.org/10.3390/su13041682 - 4 Feb 2021

Cited by 55 | Viewed by 4951

Abstract

The study presents an updated overview of the 14 non-endemic threatened crop wild relatives (CWR) in Italy: Aegilops biuncialis, Ae. uniaristata, Ae. ventricosa, Asparagus pastorianus, Beta macrocarpa, Brassica insularis, B. montana, Crambe hispanica subsp. hispanica, [...] Read more.

The study presents an updated overview of the 14 non-endemic threatened crop wild relatives (CWR) in Italy: Aegilops biuncialis, Ae. uniaristata, Ae. ventricosa, Asparagus pastorianus, Beta macrocarpa, Brassica insularis, B. montana, Crambe hispanica subsp. hispanica, C. tataria subsp. tataria, Ipomoea sagittata, Lathyrus amphicarpos, L. palustris, Vicia cusnae and V. serinica. Geographical distribution, ecology (with plant communities and habitat 92/43/EEC aspects), genetics (focused on gene pools), property, and in situ and ex situ conservation were analyzed. In addition, with the aim of their protection and valorization, specific actions are recommended. Full article

(This article belongs to the Special Issue Biodiversity 2021: Agriculture, Environment and Wellbeing)

22 pages, 9497 KiB

Open AccessEditor’s ChoiceArticle

Evaluation of Urban-Scale Building Energy-Use Models and Tools—Application for the City of Fribourg, Switzerland

by Valeria Todeschi, Roberto Boghetti, Jérôme H. Kämpf and Guglielmina Mutani

Sustainability 2021, 13(4), 1595; https://doi.org/10.3390/su13041595 - 3 Feb 2021

Cited by 33 | Viewed by 6243

Abstract

Building energy-use models and tools can simulate and represent the distribution of energy consumption of buildings located in an urban area. The aim of these models is to simulate the energy performance of buildings at multiple temporal and spatial scales, taking into account [...] Read more.

Building energy-use models and tools can simulate and represent the distribution of energy consumption of buildings located in an urban area. The aim of these models is to simulate the energy performance of buildings at multiple temporal and spatial scales, taking into account both the building shape and the surrounding urban context. This paper investigates existing models by simulating the hourly space heating consumption of residential buildings in an urban environment. Existing bottom-up urban-energy models were applied to the city of Fribourg in order to evaluate the accuracy and flexibility of energy simulations. Two common energy-use models—a machine learning model and a GIS-based engineering model—were compared and evaluated against anonymized monitoring data. The study shows that the simulations were quite precise with an annual mean absolute percentage error of 12.8 and 19.3% for the machine learning and the GIS-based engineering model, respectively, on residential buildings built in different periods of construction. Moreover, a sensitivity analysis using the Morris method was carried out on the GIS-based engineering model in order to assess the impact of input variables on space heating consumption and to identify possible optimization opportunities of the existing model. Full article

(This article belongs to the Special Issue Models and Tools for Buildings’ Energy-Use Mapping and Planning at Urban Scale)

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13 pages, 3668 KiB

Open AccessEditor’s ChoiceArticle

Interaction Boundary Determination of Renewable Energy Sources to Estimate System Strength Using the Power Flow Tracing Strategy

by Namki Choi, Byongjun Lee, Dohyuk Kim and Suchul Nam

Sustainability 2021, 13(3), 1569; https://doi.org/10.3390/su13031569 - 2 Feb 2021

Cited by 7 | Viewed by 2606

Abstract

System strength is an important concept in the integration of renewable energy sources (RESs). However, evaluating system strength is becoming more ambiguous due to the interaction of RESs. This paper proposes a novel scheme to define the actual interaction boundaries of RESs using [...] Read more.

System strength is an important concept in the integration of renewable energy sources (RESs). However, evaluating system strength is becoming more ambiguous due to the interaction of RESs. This paper proposes a novel scheme to define the actual interaction boundaries of RESs using the power flow tracing strategy. Based on the proposed method, the interaction boundaries of RESs were identified at the southwest side of Korea Electric Power Corporation (KEPCO) systems. The test results show that the proposed approach always provides the identical interaction boundaries of RESs in KEPCO systems, compared to the Electric Reliability Council of Texas (ERCOT) method. The consistent boundaries could be a guideline for power-system planners to assess more accurate system strength, considering the actual interactions of the RESs. Full article

(This article belongs to the Special Issue Integration and Control of Renewable Energy and Power Electronics for Future Power Systems)

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25 pages, 3865 KiB

Open AccessEditor’s ChoiceArticle

Optimizing Wave Overtopping Energy Converters by ANN Modelling: Evaluating the Overtopping Rate Forecasting as the First Step

by José Manuel Oliver, Maria Dolores Esteban, José-Santos López-Gutiérrez, Vicente Negro and Maria Graça Neves

Sustainability 2021, 13(3), 1483; https://doi.org/10.3390/su13031483 - 1 Feb 2021

Cited by 10 | Viewed by 3076

Abstract

Artificial neural networks (ANN) are extremely powerful analytical, parallel processing elements that can successfully approximate any complex non-linear process, and which form a key piece in Artificial Intelligence models. Its field of application, being very wide, is especially suitable for the field of [...] Read more.

Artificial neural networks (ANN) are extremely powerful analytical, parallel processing elements that can successfully approximate any complex non-linear process, and which form a key piece in Artificial Intelligence models. Its field of application, being very wide, is especially suitable for the field of prediction. In this article, its application for the prediction of the overtopping rate is presented, as part of a strategy for the sustainable optimization of coastal or harbor defense structures and their conversion into Waves Energy Converters (WEC). This would allow, among others benefits, reducing their initial high capital expenditure. For the construction of the predictive model, classical multivariate statistical techniques such as Principal Component Analysis (PCA), or unsupervised clustering methods like Self Organized Maps (SOM), are used, demonstrating that this close alliance is always methodologically beneficial. The specific application carried out, based on the data provided by the CLASH and EurOtop 2018 databases, involves the creation of a useful application to predict overtopping rates in both sloping breakwaters and seawalls, with good results both in terms of prediction error, such as correlation of the estimated variable. Full article

(This article belongs to the Special Issue Renewable Energies for Sustainable Development)

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22 pages, 2125 KiB

Open AccessEditor’s ChoiceArticle

The Relationship between Renewable Energy and Economic Growth in a Time of Covid-19: A Machine Learning Experiment on the Brazilian Economy

by Cosimo Magazzino, Marco Mele and Giovanna Morelli

Sustainability 2021, 13(3), 1285; https://doi.org/10.3390/su13031285 - 26 Jan 2021

Cited by 86 | Viewed by 8463

Abstract

This paper examines the relationship between renewable energy consumption and economic growth in Brazil, in the Covid-19 pandemic. Using an Artificial Neural Networks (ANNs) experiment in Machine Learning, we tried to verify if a more intensive use of renewable energy could generate a [...] Read more.

This paper examines the relationship between renewable energy consumption and economic growth in Brazil, in the Covid-19 pandemic. Using an Artificial Neural Networks (ANNs) experiment in Machine Learning, we tried to verify if a more intensive use of renewable energy could generate a positive GDP acceleration in Brazil. This acceleration could offset the harmful effects of the Covid-19 global pandemic. Empirical findings show that an ever-greater use of renewable energies may sustain the economic growth process. In fact, through a model of ANNs, we highlighted how an increasing consumption of renewable energies triggers an acceleration of the GDP compared to other energy variables considered in the model. Full article

(This article belongs to the Special Issue Energy Consumption and Financial Development)

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14 pages, 11845 KiB

Open AccessEditor’s ChoiceArticle

A New Regulatory Approach for PV-Based Self-Supply, Validated by a Techno-Economic Assessment: A Case Study for Slovenia

by Luka Martin Tomažič, Niko Lukač and Gorazd Štumberger

Sustainability 2021, 13(3), 1290; https://doi.org/10.3390/su13031290 - 26 Jan 2021

Cited by 1 | Viewed by 2038

Abstract

When it comes to the proliferation of photovoltaic (PV) systems, technological solutions have to go hand in hand with optimized policy approaches and regulatory frameworks. This paper proposes a new application of state-of-the-art PV potential estimation method based on Light Detection And Ranging [...] Read more.

When it comes to the proliferation of photovoltaic (PV) systems, technological solutions have to go hand in hand with optimized policy approaches and regulatory frameworks. This paper proposes a new application of state-of-the-art PV potential estimation method based on Light Detection And Ranging (LiDAR) data targeted toward individual household self-supply. The performance of the proposed general approach is demonstrated in the case of Slovenian PV based self-supply (yearly net self-sufficient energy supply) scheme and related policy. The results obtained by PV potential assessment method show drawbacks of the current policy solution in Slovenia, which limits the installed peak power of the PV systems to 80% of the rated power supply. The paper proposes to change the policy in a way that increases the yearly energy production of the PV system and assures proper voltage profiles in the electricity network. The paper is novel in terms of considering PV potential over LiDAR data by also considering self-sustainability, in using such techno-economic analysis to validate the merits and demerits of a policy approach and is the first such case study used in the context of Slovenian self-supply policy. The proposed PV potential estimation method is generally applicable for any location and can be easily adjusted to the local regulatory framework. Full article

(This article belongs to the Section Energy Sustainability)

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20 pages, 2672 KiB

Open AccessEditor’s ChoiceArticle

Expert Views on the Future Development of Biogas Business Branch in Germany, The Netherlands, and Finland until 2030

by Erika Winquist, Michiel Van Galen, Simon Zielonka, Pasi Rikkonen, Diti Oudendag, Lijun Zhou and Auke Greijdanus

Sustainability 2021, 13(3), 1148; https://doi.org/10.3390/su13031148 - 22 Jan 2021

Cited by 35 | Viewed by 10199

Abstract

To be able to meet the European Union’s energy and climate targets for 2030, all member states need to rethink their energy production and use. One potential renewable energy source is biogas. Its role has been relatively small compared to other energy sources, [...] Read more.

To be able to meet the European Union’s energy and climate targets for 2030, all member states need to rethink their energy production and use. One potential renewable energy source is biogas. Its role has been relatively small compared to other energy sources, but it could have a more central role to solve some specific challenges, e.g., to reduce carbon dioxide (CO₂) emissions from traffic, or to act as a buffer to balance electricity production with consumption. This research analyses how the future of the biogas business in three case study countries is developing until 2030. The study is based on experts’ views within the biogas business branch in Germany, The Netherlands, and Finland. Both similarities and differences were found among the experts’ answers, which reflected also the current policies in different countries. The role of biogas was seen much wider than just to provide renewable energy, but also to decrease emissions from agriculture and close loops in a circular economy. However, the future of the biogas branch is much dependent on political decisions. To be able to show the full potential of biogas technology for society, stable and predictable energy policy and cross-sector co-operation are needed. Full article

(This article belongs to the Special Issue Renewable Energy and Energy Saving: Worldwide Research Trends)

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22 pages, 6874 KiB

Open AccessEditor’s ChoiceArticle

Empirical Design, Construction, and Experimental Test of a Small-Scale Bubbling Fluidized Bed Reactor

by Carlos Vargas-Salgado, Elías Hurtado-Pérez, David Alfonso-Solar and Anders Malmquist

Sustainability 2021, 13(3), 1061; https://doi.org/10.3390/su13031061 - 20 Jan 2021

Cited by 12 | Viewed by 6001

Abstract

The methods currently used for designing a fluidized bed reactor in gasification plants do not meet an integrated methodology that optimizes all the different parameters for its sizing and operational regime. In the case of small-scale (several tens of kWs biomass gasifiers), this [...] Read more.

The methods currently used for designing a fluidized bed reactor in gasification plants do not meet an integrated methodology that optimizes all the different parameters for its sizing and operational regime. In the case of small-scale (several tens of kWs biomass gasifiers), this design is especially complex, and, for this reason, they have usually been built in a very heuristic trial and error way. In this paper, an integrated methodology tailoring all the different parameters for the design and sizing of a small-scale fluidized bed gasification plants is presented. Using this methodology, a 40 kWth biomass gasification reactor was designed, including the air distribution system. Based on this design, with several simplified assumptions, a reactor was built and commissioned. Results from the experimental tests using this gasifier are also presented in this paper. As a result, it can be said the prototype works properly, and it produces syngas able to produce thermal energy or even electricity. Full article

(This article belongs to the Section Energy Sustainability)

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17 pages, 276 KiB

Open AccessEditor’s ChoiceArticle

Applying a Practice Lens to Local Government Climate Change Governance: Rethinking Community Engagement Practices

by David Meiklejohn, Susie Moloney and Sarah Bekessy

Sustainability 2021, 13(2), 995; https://doi.org/10.3390/su13020995 - 19 Jan 2021

Cited by 4 | Viewed by 3529

Abstract

Governments commit substantial time and resources engaging individuals and households to reduce their greenhouse gas emissions. These approaches, based largely upon behaviour change theories, have been criticised for their limited reach and effectiveness by practice theorists who have offered an alternative approach, broadening [...] Read more.

Governments commit substantial time and resources engaging individuals and households to reduce their greenhouse gas emissions. These approaches, based largely upon behaviour change theories, have been criticised for their limited reach and effectiveness by practice theorists who have offered an alternative approach, broadening the focus beyond individuals. While practice theory has provided valuable insights into the energy consuming activities of households it has gained limited traction as a way to analyse and inform government practices and policy making. We address this by applying a practice lens to climate change community engagement practices performed by Australian local governments. Drawing on 29 interviews with practitioners and analysis of 37 Australian local government climate strategies, we examine the bundle of practices that constitute climate change community engagement: recruitment, engagement and evaluation. We consider how these practices are situated vis-a-vis other climate governance practices (regulation, service delivery, infrastructure provision and advocacy) as well as internal local government processes. Using a practice lens reveals the weaknesses in current engagement approaches which we contend are limiting efficacy. We draw upon Spurling et al.’s conceptualisation of re-crafting, re-integrating and substituting practices to consider how climate change community engagement practices might be reconfigured to improve their effectiveness. Full article

(This article belongs to the Section Air, Climate Change and Sustainability)

24 pages, 1742 KiB

Open AccessEditor’s ChoiceArticle

Historical Ecology of Scandinavian Infield Systems

by Ove Eriksson, Matilda Arnell and Karl-Johan Lindholm

Sustainability 2021, 13(2), 817; https://doi.org/10.3390/su13020817 - 15 Jan 2021

Cited by 15 | Viewed by 4463

Abstract

Infield systems originated during the early Iron Age and existed until the 19th century, although passing many transitions and changes. The core features of infield systems were enclosed infields with hay-meadows and crop fields, and unenclosed outland mainly used for livestock grazing. We [...] Read more.

Infield systems originated during the early Iron Age and existed until the 19th century, although passing many transitions and changes. The core features of infield systems were enclosed infields with hay-meadows and crop fields, and unenclosed outland mainly used for livestock grazing. We examine the transitions and changes of domesticated landscapes with infield systems using the framework of human niche construction, focusing on reciprocal causation affecting change in both culture and environment. A first major transition occurred during the early Middle Ages, as a combined effect of a growing elite society and an increased availability of iron promoted expansion of villages with partly communal infields. A second major transition occurred during the 18th and 19th centuries, due to a then recognized inefficiency of agricultural production, leading to land reforms. In outlands, there was a continuous expansion of management throughout the whole period. Even though external factors had significant impacts as well, human niche construction affected a range of cultural and environmental features regarding the management and structure of domesticated landscapes with infield systems. Thus, niche construction theory is a useful framework for understanding the historical ecology of infield systems. Full article

(This article belongs to the Special Issue Historical Ecology, Archaeology and Biocultural Landscapes: Cross-Disciplinary Approaches to the Long Anthropocene)

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16 pages, 2484 KiB

Open AccessEditor’s ChoiceArticle

Multi-Objective Stochastic Optimization for Determining Set-Point of Wind Farm System

by Van-Hai Bui, Akhtar Hussain, Thai-Thanh Nguyen and Hak-Man Kim

Sustainability 2021, 13(2), 624; https://doi.org/10.3390/su13020624 - 11 Jan 2021

Cited by 5 | Viewed by 2642

Abstract

Due to the uncertainty in output power of wind farm (WF) systems, a certain reserve capacity is often required in the power system to ensure service reliability and thereby increasing the operation and investment costs for the entire system. In order to reduce [...] Read more.

Due to the uncertainty in output power of wind farm (WF) systems, a certain reserve capacity is often required in the power system to ensure service reliability and thereby increasing the operation and investment costs for the entire system. In order to reduce this uncertainty and reserve capacity, this study proposes a multi-objective stochastic optimization model to determine the set-points of the WF system. The first objective is to maximize the set-point of the WF system, while the second objective is to maximize the probability of fulfilling that set-point in the real-time operation. An increase in the probability of satisfying the set-point can reduce the uncertainty in the output power of the WF system. However, if the required probability increases, the set-point of the WF system decreases, which reduces the profitability of the WF system. Using the proposed method helps the WF operator in determining the optimal set-point for the WF system by making a trade-off between maximizing the set-point of WF and increasing the probability of fulfilling this set-point in real-time operation. This ensures that the WF system can offer an optimal set-point with a high probability of satisfying this set-point to the power system and thereby avoids a high penalty for mismatch power. In order to show the effectiveness of the proposed method, several case studies are carried out, and the effects of various parameters on the optimal set-point for the WF system are also analyzed. According to the parameters from the transmission system operator (TSO) and wind speed profile, the WF operator can easily determine the optimal set-point using the proposed strategy. A comparison of the profits that the WF system achieved with and without the proposed method is analyzed in detail, and the set-point of the WF system in different seasons is also presented. Full article

(This article belongs to the Special Issue Renewable Energy and Energy Saving: Worldwide Research Trends)

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14 pages, 839 KiB

Open AccessEditor’s ChoiceArticle

Customer Behavioral Reactions to Negative Experiences during the Product Return

by Kateryna Lysenko-Ryba and Dominik Zimon

Sustainability 2021, 13(2), 448; https://doi.org/10.3390/su13020448 - 6 Jan 2021

Cited by 35 | Viewed by 8913

Abstract

This paper takes a closer look at customer experience during product return and the customer’s ability to share information about it. The research process included the development of research tools such as questionnaires. Anonymous surveys were conducted by computer assisted web interview among [...] Read more.

This paper takes a closer look at customer experience during product return and the customer’s ability to share information about it. The research process included the development of research tools such as questionnaires. Anonymous surveys were conducted by computer assisted web interview among individual customers from Poland on a sample 327 respondents. Non-stratified random sampling was used, as we considered it to be the most effective in terms of the effort-benefit ratio of the survey. A contingency table was constructed from the responses, the observed values and expected values were compared, and the Pearson Chi-square and the p-value of Fisher’s exact test were calculated. The research process carried out as well as the analysis of the obtained results allowed us to respond to the research questions. As a result, it can be stated that the clients, both satisfied (80.1%) and dissatisfied (84,4%), tended to share their opinion about return experience with other potential clients. Moreover, 42.2% of the respondents declared that they would not buy again from a seller after an unsuccessful return operation. The presented conclusions enrich the theoretical understanding of customer behavior and their purchase intention. It also offers retailers a quantitative benchmark and new perspective on the design of return policy in order to improve customer satisfaction. Full article

(This article belongs to the Special Issue Supply Chain Management for Sustainable Development)

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24 pages, 7802 KiB

Open AccessEditor’s ChoiceArticle

Correlation Analysis of the Spread of Household-Sized Photovoltaic Power Plants and Various District Indicators: A Case Study

by Nóra Hegedűsné Baranyai, Henrik Zsiborács, András Vincze, Nóra Rodek, Martina Makai and Gábor Pintér

Sustainability 2021, 13(2), 482; https://doi.org/10.3390/su13020482 - 6 Jan 2021

Cited by 9 | Viewed by 2396

Abstract

As efforts are made worldwide to meet the growing energy needs of the population in a more sustainable way, harnessing weather-dependent renewable energy sources is becoming more and more important. One of the available technologies is photovoltaic energy production. In the last decade, [...] Read more.

As efforts are made worldwide to meet the growing energy needs of the population in a more sustainable way, harnessing weather-dependent renewable energy sources is becoming more and more important. One of the available technologies is photovoltaic energy production. In the last decade, there has been a growing need among households, institutions, and businesses to reduce the use of fossil-fuel-based electricity from the public grid. In order to meet their electricity demand in Hungary, investors prefer using household-sized photovoltaic power plant (HMKE) systems. The novelty of this study is that it examines the number and total power of photovoltaic HMKEs at the district level in the service areas of different electricity distributors, taking into account the social, economic, infrastructural, and welfare dimensions of these districts as well. The study seeks to uncover whether there is a correlation between the number and total power of these types of power plants and the indicators of the districts, and if so, how strong these relationships are. The examination of the relationships also involved, in addition to correlations by pairs, the relationships of the ranking of the districts according to the complex indicators created from the district indicators and the ranking of the districts based on the number and power of photovoltaic HMKEs per 1000 members of the population. By exploring correlations, the paper seeks to establish a regression model for the number of photovoltaic HMKEs and the territorial (district) indicators. Full article

(This article belongs to the Special Issue Economic Evaluation of Renewable Energy Sources)

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26 pages, 736 KiB

Open AccessEditor’s ChoiceReview

The Role of Green and Blue Hydrogen in the Energy Transition—A Technological and Geopolitical Perspective

by Michel Noussan, Pier Paolo Raimondi, Rossana Scita and Manfred Hafner

Sustainability 2021, 13(1), 298; https://doi.org/10.3390/su13010298 - 31 Dec 2020

Cited by 507 | Viewed by 42840

Abstract

Hydrogen is currently enjoying a renewed and widespread momentum in many national and international climate strategies. This review paper is focused on analysing the challenges and opportunities that are related to green and blue hydrogen, which are at the basis of different perspectives [...] Read more.

Hydrogen is currently enjoying a renewed and widespread momentum in many national and international climate strategies. This review paper is focused on analysing the challenges and opportunities that are related to green and blue hydrogen, which are at the basis of different perspectives of a potential hydrogen society. While many governments and private companies are putting significant resources on the development of hydrogen technologies, there still remains a high number of unsolved issues, including technical challenges, economic and geopolitical implications. The hydrogen supply chain includes a large number of steps, resulting in additional energy losses, and while much focus is put on hydrogen generation costs, its transport and storage should not be neglected. A low-carbon hydrogen economy offers promising opportunities not only to fight climate change, but also to enhance energy security and develop local industries in many countries. However, to face the huge challenges of a transition towards a zero-carbon energy system, all available technologies should be allowed to contribute based on measurable indicators, which require a strong international consensus based on transparent standards and targets. Full article

(This article belongs to the Special Issue Hydrogen Economy: Challenges and Opportunities)

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19 pages, 836 KiB

Open AccessEditor’s ChoiceArticle

Critical Success Factors of the Project Management in Relation to Industry 4.0 for Sustainability of Projects

by Jaroslav Vrchota, Petr Řehoř, Monika Maříková and Martin Pech

Sustainability 2021, 13(1), 281; https://doi.org/10.3390/su13010281 - 30 Dec 2020

Cited by 97 | Viewed by 30681

Abstract

Sustainability has recently become a phenomenon; small and medium-sized enterprises (SMEs) are increasingly emphasizing the principles of sustainability in their corporate governance. They implement these changes through project management. The purpose of the paper is to determine the critical success factors in project [...] Read more.

Sustainability has recently become a phenomenon; small and medium-sized enterprises (SMEs) are increasingly emphasizing the principles of sustainability in their corporate governance. They implement these changes through project management. The purpose of the paper is to determine the critical success factors in project management, as seen by the managers of Czech manufacturing enterprises, related to the most to the successful completion of the projects. We aim to analyze the relation of these success factors to Industry 4.0, Human Resources, and sustainability. We determined the possible interconnectedness of the critical success factors using correlation coefficients. Then, we compared them using the Mann-Whitney test with new corporate management trends. The results show that companies consider Leadership and Experiences, and Employees and Flexibility to be key factors in project management’s success. The most important critical factor for the sustainability of projects focused on Industry 4.0 is the finances that decide the implementation of projects. The benefits of Industry 4.0 concerning sustainability have been identified in projects aimed at implementing new energy sources. In addition to the results obtained, the development of a methodology for evaluating Industry 4.0 projects’ success concerning sustainability may be based on critical success factors in the future. Full article

(This article belongs to the Special Issue Sustainability and Project Management)

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19 pages, 289 KiB

Open AccessEditor’s ChoiceArticle

How Does Consumers’ Care for Origin Shape Their Behavioural Gap for Environmentally Friendly Products?

by Maria Teresa Trentinaglia De Daverio, Teresina Mancuso, Massimo Peri and Lucia Baldi

Sustainability 2021, 13(1), 190; https://doi.org/10.3390/su13010190 - 28 Dec 2020

Cited by 10 | Viewed by 3424

Abstract

Climate change is threatening worldwide crop yields and varieties, and the desertification of Southern Europe and Mediterranean areas is endangering the cultivation of tomato, not only one of the most important cultivated crops, but also one of the main pillars of the global [...] Read more.

Climate change is threatening worldwide crop yields and varieties, and the desertification of Southern Europe and Mediterranean areas is endangering the cultivation of tomato, not only one of the most important cultivated crops, but also one of the main pillars of the global food industry. To minimize its environmental impact, current research efforts in Europe are selecting resilient tomato genotypes with reduced use of water and fertilizers. Still, its commercial acceptance depends on consumers’ reaction in terms of interests, attitudes, and willingness to buy and pay for this hypothetical resilient tomato. In our setting, a behavioural gap exists whenever despite an interest for the product, and regardless of a positive attitude towards it, consumers are not willing to pay a premium price for this tomato. This paper focuses on Italians, among the largest tomato consumers across the world, and for whom origin emerges as a relevant consumption driver. We carried out a web-survey, totalling 932 responses. We ran three different ordinal regressions, one for each level of involvement in the purchasing process, identifying the factors affecting consumers’ interest, attitude, and behaviour towards this hypothetical tomato. We prove the existence of a behavioural gap for Italian tomato consumers and observe that this gap widens as consumers’ preferences for origin increase. Hence, policies developing environmentally sustainable products should not forget how consumer preferences for non-strictly environmental attributes might ultimately affect their propensity to buy and pay. Full article

(This article belongs to the Special Issue Sustainable Agribusiness and Food Marketing)

16 pages, 2811 KiB

Open AccessEditor’s ChoiceArticle

The Influence of Hydrogen on Vaporization, Mixture Formation and Combustion of Diesel Fuel at an Automotive Diesel Engine

by Alexandru Cernat, Constantin Pana, Niculae Negurescu, Gheorghe Lazaroiu and Cristian Nutu

Sustainability 2021, 13(1), 202; https://doi.org/10.3390/su13010202 - 28 Dec 2020

Cited by 15 | Viewed by 3549

Abstract

Hydrogen can be a viable alternative fuel for modern diesel engines, offering benefits on efficiency and performance improvement. The paper analyses the results of a thermodynamic model developed by authors in order to study the influence of Hydrogen addition on a process like [...] Read more.

Hydrogen can be a viable alternative fuel for modern diesel engines, offering benefits on efficiency and performance improvement. The paper analyses the results of a thermodynamic model developed by authors in order to study the influence of Hydrogen addition on a process like vaporization, mixture forming, and combustion at the level of diesel fuel droplets. The bi-zonal model is applied for a dual-fueled diesel engine K9K type designed by Renault for automotives. For the engine operating regime of 2000 rpm speed and 55% engine load, the diesel fuel is partially substituted by Hydrogen in energetic percents of 6.76%, 13.39%, and 20.97%, the engine power being maintained at the same level comparative to classic fueling. At Hydrogen addition, the diesel fuel jets atomization and diesel fuel droplets vaporization are accelerated, the speed of formation of the mixture being increased. Comparative to classic fueling, the use of Hydrogen leads to diesel droplets combustion intensification, with a shortened autoignition delay, reduction of combustion duration, and increase of flame radius. Full article

(This article belongs to the Special Issue Sustainable Development of Modern Society through Design and Integration of Efficient Energy Technologies)

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11 pages, 1119 KiB

Open AccessEditor’s ChoiceReview

Food Security during the Pandemic and the Importance of the Bioeconomy in the New Era

by Anca C. Farcas, Charis M. Galanakis, Carmen Socaciu, Oana L. Pop, Dorin Tibulca, Adriana Paucean, Mirela A. Jimborean, Melinda Fogarasi, Liana C. Salanta, Maria Tofana and Sonia A. Socaci

Sustainability 2021, 13(1), 150; https://doi.org/10.3390/su13010150 - 25 Dec 2020

Cited by 39 | Viewed by 8434

Abstract

One of the biggest challenges in managing the food sector during a pandemic crisis is sustaining a robust food security system and adopting the right strategies in correlating the consumers’ needs and requirements with those of food safety, the producers, the distribution chain, [...] Read more.

One of the biggest challenges in managing the food sector during a pandemic crisis is sustaining a robust food security system and adopting the right strategies in correlating the consumers’ needs and requirements with those of food safety, the producers, the distribution chain, the economic environment, and waste management. The restrictions on people’s global movement, commodities, and services and the measures taken to reduce the spread of COVID-19 have disrupted food environments around the world and forced us to collectively redesign and optimize our systems using existing resources from a more sustainable perspective. This paper offers an overview of the implications of COVID-19 for the food supply chain and discusses several potential strategies for tackling short- and long-term adverse effects resulting from the pandemic. Full article

(This article belongs to the Special Issue High Added-Value Molecules Recovered from Agri-Food Waste and by-Products)

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14 pages, 1348 KiB

Open AccessEditor’s ChoiceArticle

Healthy Diet Assistance for the Most Deprived in Post-Crisis Greece: An Evaluation of the State Food Provision Program

by Antonis Vlassopoulos, Konstantina Filippou, Aleks Pepa, Olga Malisova, Dimitra Xenaki and Maria Kapsokefalou

Sustainability 2021, 13(1), 99; https://doi.org/10.3390/su13010099 - 24 Dec 2020

Cited by 4 | Viewed by 3348

Abstract

In 2016, the European Union set up the Fund for European Aid to the Most Deprived (FEAD) as its first structured food provision program to combat food insecurity. Computational analysis and a cross-sectional survey took place from January 2016 to June 2018 to [...] Read more.

In 2016, the European Union set up the Fund for European Aid to the Most Deprived (FEAD) as its first structured food provision program to combat food insecurity. Computational analysis and a cross-sectional survey took place from January 2016 to June 2018 to calculate FEAD’s contribution to its beneficiaries’ diets and to collect beneficiary satisfaction data. Dairy, fresh meat, legumes, sugar, olive oil, and tomato concentrate were the most commonly procured items. The program’s contribution to vegetable, dairy, and grains intake was 3.4%, 6.1%, and 6.0%, respectively, as opposed to discretionary calories (12.2%) and fats/oils (24.5%). The program’s algorithm greatly favors (almost 3-fold) single-person applications, compared with applications with four or more people. Beneficiaries valued each food provision at 21.23 ± 23.4 euros, which, for 64.4% of them, translated to a high positive impact on the household budget. FEAD had a highly positive impact on feelings of anxiety and security, for 50.7% and 41.6% of its beneficiaries. Satisfaction with the foods provided was also high for ~70% of the beneficiaries. The program is met with high beneficiary satisfaction and is perceived as a substantial assistance. Increases in the amounts and variety of foods delivered, with a focus on fruit, vegetables, and fish, should be considered to further improve the program’s dietary impact. Full article

(This article belongs to the Special Issue Gaps and Opportunities in Addressing Food Insecurity under the Sustainable Development Framework)

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17 pages, 501 KiB

Open AccessEditor’s ChoiceArticle

Modelling Attitude towards Consumption of Vegan Products

by Isabel Miguel, Arnaldo Coelho and Cristela Maia Bairrada

Sustainability 2021, 13(1), 9; https://doi.org/10.3390/su13010009 - 22 Dec 2020

Cited by 29 | Viewed by 16970

Abstract

This study proposes to understand the impact of personal (health awareness and social influence) and moral (environmental concerns and animal welfare) antecedents on attitudes towards veganism and their effects on engagement with vegan products, along with their impact on purchase intention and word [...] Read more.

This study proposes to understand the impact of personal (health awareness and social influence) and moral (environmental concerns and animal welfare) antecedents on attitudes towards veganism and their effects on engagement with vegan products, along with their impact on purchase intention and word of mouth. Idealism is presented as a moderator of these proposed relationships. The study uses a structured questionnaire to gather data from two cross-sectional samples of 224 Portuguese and 356 Brazilian vegans collected from Facebook groups of vegans. Structural equation modelling is used to test the seven proposed hypotheses and the moderation effects. This research compares the influence of personal and moral determinants on veganism using idealism as a specific context to investigate their relationships, comparing Brazilian and Portuguese respondents and the effects of national cultures. Results show that attitudes towards veganism do not depend on personal causes, but rather on moral concerns. Motivations to reduce animal consumption, protect nature, and respect animal life seem to be guided by ethical principles. Full article

(This article belongs to the Collection Agricultural Economics and Sustainable Food Consumption)

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16 pages, 2746 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Climate Change and Ski Tourism Sustainability: An Integrated Model of the Adaptive Dynamics between Ski Area Operations and Skier Demand

by Daniel Scott, Robert Steiger, Michelle Rutty, Marc Pons and Peter Johnson

Sustainability 2020, 12(24), 10617; https://doi.org/10.3390/su122410617 - 18 Dec 2020

Cited by 28 | Viewed by 8922

Abstract

Climate change is an evolving business reality influencing the sustainability of ski tourism worldwide. A new integrated model of the co-evolution of supply (27 ski areas) and demand-side (skier behaviour) climate change adaptation in the ski tourism market of Ontario, Canada is presented. [...] Read more.

Climate change is an evolving business reality influencing the sustainability of ski tourism worldwide. A new integrated model of the co-evolution of supply (27 ski areas) and demand-side (skier behaviour) climate change adaptation in the ski tourism market of Ontario, Canada is presented. Ski area operations are modeled under a high-emission 2050s scenario, with skier responses to altered operations informed by a survey of 2429 skiers. These market adaptive dynamics reveal new insights into differential climate risk, capturing patterns not apparent when considering only operational conditions of ski resorts. A decoupling of ski season length and skier visitation was found at four ski areas, where, despite average season length losses, visitation increased as a result of reduced competition. Simulated skier visit losses were smaller than reductions in season length, contributing to an increase in crowding. Growing the market of skiers was also identified as a critical adaptation strategy that could offset skier visit losses from shortened seasons. Climate change challenges the future sustainability of ski areas in this market in several ways: profitability of ski areas with substantially shorter seasons, increased snowmaking costs, crowding impacts on visitor experience, and potential overtourism at the few most climate resilient destinations. Full article

(This article belongs to the Section Air, Climate Change and Sustainability)

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16 pages, 4329 KiB

Open AccessEditor’s ChoiceArticle

Emergy and Sustainability Ternary Diagrams of Energy Systems: Application to Solar Updraft Tower

by Islam Elsayed and Yoshiki Nishi

Sustainability 2020, 12(24), 10546; https://doi.org/10.3390/su122410546 - 16 Dec 2020

Cited by 5 | Viewed by 4333

Abstract

To facilitate sustainable energy development, one has to understand the limited availability of nonrenewable energy resources, and the ability of the earth to renew or recover. Emergy is an instrument that measures environmental loading, ecological economics, and regional sustainable development. In this study, [...] Read more.

To facilitate sustainable energy development, one has to understand the limited availability of nonrenewable energy resources, and the ability of the earth to renew or recover. Emergy is an instrument that measures environmental loading, ecological economics, and regional sustainable development. In this study, emergy indicators are calculated to investigate the sustainability of solar updraft tower (SUT). SUT produces energy from the hot air, utilizing a combination of a solar collector, central tower, and air turbines. The results demonstrate that the sustainability of SUT grew as the size of the plant increased. Further, emergetic ternary diagrams are drawn to facilitate the comparison between SUT and various technologies. The resources-use efficiency of wind energy and SUT, 200 MW is found to be the lowest among all energy technologies presented in this research. Scenario analysis is performed to explore the future optimization directions. The results demonstrate that the development direction of SUT systems should mainly focus on reducing the materials demanded by the manufacturing and construction of its solar collectors. This study aims to demonstrate the value of emergy as a powerful instrument for drawing long-term sustainable strategies in energy markets for a greener tomorrow. Full article

(This article belongs to the Special Issue Renewable Energies for Sustainable Development)

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12 pages, 7513 KiB

Open AccessEditor’s ChoiceArticle

Design and Implementation of a Co-Simulation Framework for Testing of Automated Driving Systems

by Demin Nalic, Aleksa Pandurevic, Arno Eichberger and Branko Rogic

Sustainability 2020, 12(24), 10476; https://doi.org/10.3390/su122410476 - 15 Dec 2020

Cited by 20 | Viewed by 4141

Abstract

The increasingly used approach of combining different simulation softwares in testing of automated driving systems (ADSs) increases the need for potential and convenient software designs. Recently developed co-simulation platforms (CSPs) provide the possibility to cover the high demand for testing kilometers for ADSs [...] Read more.

The increasingly used approach of combining different simulation softwares in testing of automated driving systems (ADSs) increases the need for potential and convenient software designs. Recently developed co-simulation platforms (CSPs) provide the possibility to cover the high demand for testing kilometers for ADSs by combining vehicle simulation software (VSS) with traffic flow simulation software (TFSS) environments. The emphasis on the demand for testing kilometers is not enough to choose a suitable CSP. The complexity levels of the vehicle, object, sensors, and environment models used are essential for valid and representative simulation results. Choosing a suitable CSP raises the question of how the test procedures should be defined and constructed and what the relevant test scenarios are. Parameters of the ADS, environments, objects, and sensors in the VSS, as well as traffic parameters in the TFSS, can be used to define and generate test scenarios. In order to generate a large number of scenarios in a systematic and automated way, suitable and appropriate software designs are required. In this paper, we present a software design for a CSP based on the Model–View–Controller (MVC) design pattern as well as an implementation of a complex CSP for virtual testing of ADSs. Based on this design, an implementation of a CSP is presented using the VSS from IPG Automotive (CarMaker) and the TFSS from the PTV Group (Vissim). The results showed that the presented CSP design and the implementation of the co-simulation can be used to generate relevant scenarios for testing of ADSs. Full article

(This article belongs to the Collection Sustainable Development of Electric Vehicle)

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20 pages, 1674 KiB

Open AccessEditor’s ChoiceArticle

Investigation of the Use of Low Temperature Geothermal Organic Rankine Cycle Engine in an Autonomous Polygeneration Microgrid

by George Kyriakarakos, Erika Ntavou and Dimitris Manolakos

Sustainability 2020, 12(24), 10475; https://doi.org/10.3390/su122410475 - 15 Dec 2020

Cited by 12 | Viewed by 2690

Abstract

Low-enthalpy geothermal resources (<150 °C) can be used for electricity generation and are widespread around the world, occurring at shallow depths. At the same time, in many parts of the world, there are existing low-enthalpy geothermal wells that are used for a multitude [...] Read more.

Low-enthalpy geothermal resources (<150 °C) can be used for electricity generation and are widespread around the world, occurring at shallow depths. At the same time, in many parts of the world, there are existing low-enthalpy geothermal wells that are used for a multitude of applications such as for buildings’ heating and agriculture-related applications. The dominant technology to convert low-grade heat (<150 °C) to electricity is the Organic Rankine Cycle (ORC). The autonomous polygeneration microgrid (APM) concept aims to holistically meet in a sustainable way the needs of an off-grid community in terms of electrical loads, space heating and cooling, potable water production through desalination, and the use of hydrogen as fuel for transportation, in the most cost-effective manner possible. Photovoltaics (PVs) and wind turbines have been investigated extensively, since PVs can be installed practically anywhere in the world and wind turbines in areas with sufficient wind potential. The aim of this paper is to investigate techno-economically the potential of utilizing low-enthalpy geothermal resources in small-scale APMs through an ORC engine to fully satisfy the needs of small settlements. In order to accomplish this task with confidence, a case study for the Greek island of Milos has been developed and a typical settlement has been considered. It is worth mentioning that experimental results from a realized low-power (<10 kW_e) ORC engine manufactured to operate at temperatures up to 140 °C are used to add reliability in the calculations. In order to meet the needs of the people, four different APMs based on PVs, wind turbines, and geothermal ORC of different but appropriate configurations were designed and sized through optimization. The optimization process was based on particle swarm optimization (PSO). The comparative examination of the results shows that the use of a low-power, low-temperature ORC engine in an APM is technically feasible; more cost effective than the configurations based on PVs, wind turbines, or combination of both; and has increased environmental sustainability. Full article

(This article belongs to the Special Issue Smart Microgrid Systems)

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11 pages, 1935 KiB

Open AccessEditor’s ChoiceArticle

A Study on State of Charge and State of Health Estimation in Consideration of Lithium-Ion Battery Aging

by Woongchul Choi

Sustainability 2020, 12(24), 10451; https://doi.org/10.3390/su122410451 - 14 Dec 2020

Cited by 9 | Viewed by 4293

Abstract

Due to rapid development of industries around the world, more and more consumption of fossil fuels was unavoidable, resulting in serious environmental problems. The many pollutant emissions—a major contributor to global warming and weather pattern change—have been at the center of concern. In [...] Read more.

Due to rapid development of industries around the world, more and more consumption of fossil fuels was unavoidable, resulting in serious environmental problems. The many pollutant emissions—a major contributor to global warming and weather pattern change—have been at the center of concern. In order to solve this issue, research and development of electric vehicles and energy storage systems made great progress and successfully introduced products in the market. Nevertheless, accurate measurement of the state of charge (SOC) and state of health (SOH) of the Li-ion battery, the most popular electric energy storage device, has not yet been fully understood due to the nature of battery aging. In this study, ideas to estimate the capacity and ultimately SOC and SOH of Li-ion batteries are discussed. With these ideas, we expect not only to accommodate the issues with battery aging but also to implement an algorithm for an on-board battery management system. The key idea is to chase and monitor internal resistance continuously in a fast and reliable manner in real time. With further investigation of the key idea, we also fully expect to come up with a reliable SOC and SOH measurement scheme in the near future. Full article

(This article belongs to the Collection Sustainable Development of Electric Vehicle)

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15 pages, 250 KiB

Open AccessEditor’s ChoiceArticle

Land Fragmentation, Technical Efficiency, and Adaptation to Climate Change by Farmers in the Gamo Highlands of Ethiopia

by Tesfaye C. Cholo, Jack Peerlings and Luuk Fleskens

Sustainability 2020, 12(24), 10304; https://doi.org/10.3390/su122410304 - 10 Dec 2020

Cited by 5 | Viewed by 3291

Abstract

Although barley production is vulnerable to the impacts of climate change, households in the Gamo Highlands of Ethiopia rely on barley for their diet and allocate most of their highly-fragmented land to barley production. Moreover, farmers alter land management practices as a strategy [...] Read more.

Although barley production is vulnerable to the impacts of climate change, households in the Gamo Highlands of Ethiopia rely on barley for their diet and allocate most of their highly-fragmented land to barley production. Moreover, farmers alter land management practices as a strategy to adjust to climate change and variability. However, to what extent land fragmentation and land management jointly influence the technical efficiency of barley production is unknown. In addition, it is unidentified whether technical efficiency is uniform across multiple separated plots. In this study, we adapted two stochastic frontier panel models on plot-level cross-sectional data to investigate this. The model results indicate that fragmentation influences the effect of land management practices on efficiency. The study found that efficiency was not uniform across different plots and for different farmers and showed the existence of large yield gaps. To close these gaps, policies designed to address the specific components of inefficiency need to be implemented. Full article

(This article belongs to the Special Issue Implications of Climate Change for Ecosystems and Society)

10 pages, 3106 KiB

Open AccessEditor’s ChoiceArticle

A Comparative Study of Initial Cost Recuperation Period of Plug-In Series Hybrid Electric Two-Wheel Vehicles in Southeast Asian Countries

by Woongchul Choi and Seokho Yun

Sustainability 2020, 12(24), 10340; https://doi.org/10.3390/su122410340 - 10 Dec 2020

Cited by 6 | Viewed by 2951

Abstract

While pollutant emissions from vehicles are under heavy scrutiny all around the world, small two-wheelers have not been under strict regulations until recently. Especially in the region of Southeast Asia, a tremendous number of old, in-house rebuilt and outdated two-wheelers are in operation [...] Read more.

While pollutant emissions from vehicles are under heavy scrutiny all around the world, small two-wheelers have not been under strict regulations until recently. Especially in the region of Southeast Asia, a tremendous number of old, in-house rebuilt and outdated two-wheelers are in operation and, as a result, pollutant emission problems are one of the most serious concerns of the communities. Since electric grid systems for consistent and stable supply of electricity are not there yet, thus plug-in series hybrid two-wheel vehicles have attracted much attention and are thought to be a meaningful solution for many people in the region. In the current study, an energy simulation tool has been developed to compare the ownership cost of an internal combustion engine (ICE)-based two-wheeler and that of a plug-in series hybrid electric scooter. To estimate annual energy cost (sum of gasoline and electricity cost), gasoline prices and household electricity rates in major Southeast Asian countries were collected. In addition, the nominal initial vehicle prices of ICE-based scooters and those of plug-in series hybrid electric two-wheel vehicles were gathered to estimate the time for the recovery of the initial investment. Full article

(This article belongs to the Collection Sustainable Development of Electric Vehicle)

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28 pages, 675 KiB

Open AccessEditor’s ChoiceArticle

Impact of Strategic Cooperation under Competition on Green Product Manufacturing

by Izabela Nielsen, Sani Majumder, Eryk Szwarc and Subrata Saha

Sustainability 2020, 12(24), 10248; https://doi.org/10.3390/su122410248 - 8 Dec 2020

Cited by 25 | Viewed by 3486

Abstract

This study explores the optimal pricing and investment decision for two competing green supply chains, both consisting of a manufacturer and an exclusive retailer. Our focus is to explore, does the strategic integration decision with rivals at the horizontal level or with partners [...] Read more.

This study explores the optimal pricing and investment decision for two competing green supply chains, both consisting of a manufacturer and an exclusive retailer. Our focus is to explore, does the strategic integration decision with rivals at the horizontal level or with partners at the vertical level have any effect on green product types? The results reveal the following insights: retailer-retailer strategic integration at downstream level leads to a sub-optimal total supply chain profit and green quality level for a development-intensive green product. Two competing manufacturers can produce products at a higher level if they are vertically integrated with respective retailers. Manufacturer-manufacturer integration at upstream level sometimes leads to higher profits and product quality level if cross price-elasticity of consumers is high. However, an opposite phenomenon is observed while they are selling for a marginal-intensive green product, horizontal integration can improve green quality levels, but supply chain members will receive a lower profit. Therefore, selection of green product types and strategic integration decision are interrelated to achieve the profit maximization goal along with the aim to offer products at a higher green quality level. Vertical integration strategy can outperform horizontal integration strategy, especially if cross-price elastic for green products remain high. Full article

(This article belongs to the Collection Sustainability on Production and Industrial Management)

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16 pages, 2968 KiB

Open AccessEditor’s ChoiceArticle

Decreasing Water Footprint of Electricity and Heat by Extensive Green Roofs: Case of Southern Italy

by Behrouz Pirouz, Stefania Anna Palermo, Mario Maiolo, Natale Arcuri and Patrizia Piro

Sustainability 2020, 12(23), 10178; https://doi.org/10.3390/su122310178 - 6 Dec 2020

Cited by 23 | Viewed by 3798

Abstract

Electrical and energy production have a noticeable water footprint, and buildings′ share of global energy consumption is about 40%. This study presents a comprehensive experimental analysis of different thermal impacts and water consumption of green roofs in a Mediterranean climate. The study aims [...] Read more.

Electrical and energy production have a noticeable water footprint, and buildings′ share of global energy consumption is about 40%. This study presents a comprehensive experimental analysis of different thermal impacts and water consumption of green roofs in a Mediterranean climate. The study aims to investigate the use of water directly for green roofs and reduce the water footprint of energy in summer and winter due to its thermal impacts. The measurements were carried out for an extensive green roof with an area of 55 m² and a thickness of 22 cm, and direct water consumption by a green roof and direct and indirect water consumption by cooling and heating systems were analyzed. According to the analysis, in summer, the maximum roof temperature on a conventional roof was 72 °C, while under the green roof it was 30.3 °C. In winter, the minimum roof temperature on a conventional roof was −8.6 °C, while under the green roof it was 7.4 °C. These results show that green roofs affect energy consumption in summer and winter, and the corresponding thermal requirements for the building have a water footprint regarding energy production. In summer, the thermal reduction in the water footprint by a green roof was 48 m³ if an evaporative air conditioner is used and 8.9 m³ for a compression air conditioner, whereas the water consumed in the green roof was 8.2 m³. Therefore, using water directly in the green roof would reduce the energy consumption in buildings, and thus less water has to be used in power plants to provide the same thermal impact. In winter, green roofs′ water consumption was higher than the thermal water footprint; however, there is no need to irrigate the green roof as the water consumed comes from precipitation. This experimental analysis determines that in the Mediterranean climate, green roofs allow the achievement of the same thermal conditions for buildings in both summer and winter, with a reduction in water consumption. Full article

(This article belongs to the Special Issue New Evidences of Indoor Thermal Comfort in Residential and Tertiary Buildings: Design and Evaluation Methods)

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