129 research outputs found
A wolf in sheep's clothing: Exposing the structural violence of private electric automobility
No full textThe world is running out of time to avoid cataclysmic climate impacts. Therefore, determining which decarbonisation strategies are more effective and inclusive in reducing anthropogenic dependency on fossil fuels is vital for governments' decisions on investment. This research argues that the electrification of private automobility is neither effective nor equitable. Considering the current electricity mix of the grid, this electrification merely shifts the CO2 emissions and other pollutants from urban to rural areas. The strategy of private automobility electrification does not look beyond the problem of tailpipe emissions and hence cannot eliminate the deficiencies of the car-dependent system that require system-wide solutions, such as traffic congestion and road accidents. Prioritising this strategy not only maintains existing inequities but also increases social injustice and delays the implementation of more effective interventions. We argue that using private EVs structurally violates the biosphere and human communities in three ways: (1) production of inequities, (2) pollution and waste, and (3) the space of the exception (the ‘Electric Vehicle Bubble’). Finally, we conclude that eradicating private automobility is necessary to realise climate and transport justice. Focusing on inclusive strategies, such as supporting public transportation, shared mobility, and active travel modes, instead of offering incentives for EVs, are the means of progressive redistribution of wealth and can satisfactorily meet people's basic needs and governmental climate targets.<br/
Efficiency assessment of Iran's petroleum refining industry in the presence of unprofitable output: a dynamic two-stage slacks-based measure
No full textIran ranks as the fifth largest producer of crude oil in the world. Therefore, the country has the potential to play an important role in the global petroleum products market. Surprisingly, Iran cannot satisfy the domestic demand for transportation fuels, forcing the country to import gasoline and diesel fuel. To investigate this problem, this study applies a novel dynamic two-stage slacks-based measure framework to evaluate the efficiency of the petroleum refining industry in Iran. Using data from Iranian refineries for the period 2011–2015, in the first stage, the model decomposes the efficiency of refineries into operational and profitability subunits. In the second stage, the overall efficiency scores are computed. Unlike previous studies considering byproducts like emissions as undesirable outputs, the current model incorporates mazut as an unprofitable output. The empirical results reveal low efficiency among Iranian refineries and indicate a significant negative relationship between the overall efficiency scores and amount of mazut produced in refineries. Scrupulous analysis shows that an inappropriate production pattern and lack of advanced conversion units in refineries contribute greatly to the low performance of the Iranian refining sector. These findings can be used to improve current refining industry as a step toward energy sustainability in Iran
World Heritage Sites in developing countries: Assessing impacts and handling complexities toward sustainable tourism
No full textThe current study addresses several concerns regarding World Heritage Sites (WHSs) in developing countries. Using a novel super-efficiency parallel framework, this research firstly elucidates how WHS designation impacts the tourism sector in the 21 developing nations with the greatest number of WHSs from 2000 through 2016. The proposed parallel model assesses the tourism industry at both the macro level in the context of resource-oriented efficiency and the micro level in facility-oriented efficiency. The results demonstrate that the WHS brand positively impacts the tourism demand in developing countries and can be used as a promotional tool. Secondly, this work draws attention to the socio-ecological concerns related to WHSs in developing countries. It sets out a critical and factual discussion based on the current designation and conservation status of WHSs. The analysis highlights an unfair distribution of WHSs between developing and advanced economies and reveals negligence in their preservation, since around 94% of sites labeled In Danger are located in developing nations. The study concludes that the conservation of WHSs is a complex societal problem and offers policy implications for handling heritage inscription and preservation issues in developing countries. Finally, it explores pathways toward sustainable conservation of WHSs, based on United Nations sustainable development goals (SDGs) for safeguarding heritage and sustainable communities (SDG 11), for more effective institutions (SDG 16), and for fair and nonhegemonic partnership between advanced economies and developing countries (SDG 17). The outcomes may be of practical value to policymakers aiming to improve tourism and heritage management.<br/
Optimising shared electric mobility hubs: Insights from performance analysis and factors influencing riding demand
No full textIn order to decarbonise the transport networks, systemic change is needed. One manifestation of this transformation is shared electric mobility, seeking to curtail car usage and ownership. This current case study aims to measure and optimise the operational performance of shared electric mobility hubs (eHUBs). From the performance results of eHUBs, one can get helpful insights to develop appropriate future planning and management policies for improving the transport chain. Incorporating data from September 2021 to October 2022, this research developed a novel dynamic two-stage data envelopment analysis (DEA) framework to assess the performance of the eHUB network in Inverness, Scotland. In the first stage, the DEA model computes relative efficiency scores related to the operational performance of the stations. The second stage focuses on network analysis and examining the factors that may influence the high or low obtained performance scores. Scrupulous analysis shows that the population in the catchment area of the eHUBs and the weather conditions (specifically, temperature) are among the most important factors influencing riding demand. The study also finds a weak association between eHUBs efficiency and proximity to public transport stops, suggesting that electric-assist bikes (e-bikes, pedelecs) may not strongly complement public transport, unlike bike-sharing systems. It indicates that e-bikes serve rather as a standalone mode for longer journeys. The findings of the case study can be used to improve sustainable mobility strategies, particularly related to e-bikes in other cities and urban areas
Data for: Efficiency assessment of Iran's petroleum refining industry in the presence of unprofitable output: a dynamic two-stage slacks-based measure
No full textPetroleum refineries inputs and outputs data in Iran 2011-2015.Available from: http://www.niordc.ir/index.aspx?fkeyid=&siteid=78&pageid=178
Sustainability assessment of inland transportation in China: a triple bottom line-based network DEA approach
No full textThe transport sector accounts for nearly one third of the world’s total energy use, while inland transport alone is responsible for half of the global petroleum consumption. The expansion of motorization in newly industrialized economies necessitates setting realistic targets. To support decision-makers in better assessment of transport sustainability performance, we introduce a systematic triple bottom line-based approach to evaluate inland transport, considering social, economic, and environmental dimensions of sustainability. The proposed network data envelopment analysis (DEA) measure organizes the three components of the system into a parallel structure, allocates shared input across subsystems, and incorporates undesirable output. The empirical application determines the efficiency of regional inland transportation systems in China from 2006 to 2015. The results indicate a rise in overall transport efficiency between China’s 11th and 12th five-year development plan periods and link the economic growth with a decrease in environmental transport efficiency in the Central and Western zones and with a decline in social efficiency in the Eastern zone. Since 2012, the social sustainability remains the weakest component of inland transport, which requires special attention by policy-makers to support vulnerable groups of transport users. This study provides further insight into the investigated measures and proposes recommendations for the improvement of inland transport in China
Social sustainability of regional transportation: an assessment framework with application to EU road transport
No full textThe assessment of transportation social sustainability appeals to many scholars as an essential issue but imposes a risk of selecting inadequate factors and methods to measure social phenomena. In this study, based on an extensive review, we identify the measurable key social indicators (instead of the economic or environmental factors commonly used) and propose a comprehensive evaluation framework for relative performance analysis of social sustainability in the regional context. This work is the first attempt to assess regional social sustainability of transport explicitly utilizing a multi-output performance measure. We use Shannon entropy to combine the results of selected data envelopment analysis (DEA) models into a unified social sustainability performance score. The method is applied to regional road transport in the European Union (EU) member states for the period 2004–2017. The empirical section explores individual profiles of EU countries, compares the states grouped into two clusters of old (EU-15) and new (EU-13) EU members, and examines their social sustainability performance over time. The analysis suggests that considering only social factors in the measurement eliminates the bias resulting from the inclusion of economic factors. As a result, our method prevents inaccurate inflation of the scores of more economically advanced countries. The findings also draw attention to the car dependence problem associated with high motorization rates in affluent EU-15 states. The study confirms the capacity of the proposed DEA-based framework to serve as an adequate tool for measuring the social sustainability of transport, which can support policymakers by providing useful benchmarks employing social factors
The challenge of making EVs just affordable enough: Assessing the impact of subsidies on equity and emission reduction in Ireland
No full textGovernments support the switch to electric vehicles (EVs) through subsidies and other incentives, as this is expected to help meet climate targets. This research examines the affordability of EVs for Irish households, focusing on equity implications and the impact of affordability on achieving decarbonisation goals. Affordability is estimated for eight scenarios, considering both current and reduced EV prices, and assessed across Ireland. The research finds that flat-rate subsidies do not adequately support lower-income households, impede EV adoption, and could jeopardise the achievement of emission reduction targets. Need-based subsidies would ensure more inclusive EV uptake. If current prices are considered, the target for the number of EVs on the road by 2030 can be met only with the purchase of small-sized EVs. This suggests that achieving EV targets is unlikely without promoting smaller vehicles. The current €3500 EV grant may be insufficient for many households without extended loan terms. Therefore, differentiated subsidies based on income and household size are recommended to increase EV adoption. Households in remote rural areas, where forced car ownership is high, require higher subsidies. In contrast, urban areas could receive lower subsidies to promote the use of more sustainable transport modes, such as cycling, shared mobility, and public transport.</p
E-bike to the future: scalability, emission-saving, and eco-efficiency assessment of shared electric mobility hubs
No full textIn car-dominated urban areas, shared electric micro-mobility offers a sustainable alternative to decarbonise and reshape mobility paradigms. This paper presents a comprehensive framework for evaluating Dublin's e-bike sharing system, comprising 12 stations (eHUBs). Using six months of real-world riding data, it employs data envelopment analysis to assess the eco-efficiency of each eHUB in utilising nearby infrastructure, population in the catchment area, and location to achieve desired economic, social, and environmental outputs. Results indicate an upward trajectory for the system's eco-efficiency. The returns-to-scale analysis provides insights into the system's scalability, suggesting that expanding the e-bike sharing system, along with infrastructural enhancements, would significantly increase ridership. Analysing decarbonisation, usage patterns, and spatial factors of eHUBs reveals the substantial potential of shared e-bikes if optimally used. The research highlights the need to reevaluate car-centric policies in favour of more inclusive and environmentally sustainable alternatives and proposes actionable policy recommendations to achieve this transformation.</p
Acidic versus alkaline bacterial degradation of lignin through engineered strain E. coli BL21(Lacc): exploring the differences in chemical structure, morphology, and degradation products
No full textThere is increasing interest in research on lignin biodegradation compounds as potential building blocks in applications related to renewable products. More attention is necessary to evaluate the effects of the initial pH conditions during the bacterial degradation of lignin. In this study we performed experiments on lignin biodegradation under acidic and mild alkaline conditions. For acidic biodegradation, lignin was chemically pretreated with hydrogen peroxide. Alkaline biodegradation was achieved by developing the bacterial growth on Luria and Bertani medium with alkali lignin as the sole carbon source. The mutant strain Escherichia coli BL21(Lacc) was used to carry out lignin biodegradation over 10 days of incubation. Results demonstrated that under acidic conditions there was a predominance of aliphatic compounds of the C3–C4 type. Alkaline biodegradation was produced in the context of oxidative stress, with a greater abundance of aryl compounds. The final pH values of acidic and alkaline biodegradation of lignin were 2.53 and 7.90, respectively. The results of the gas chromatography mass spectrometry analysis detected compounds such as crotonic acid, lactic acid and 3-hydroxybutanoic acid for acidic conditions, with potential applications for adhesives and polymer precursors. Under alkaline conditions, detected compounds included 2-phenylethanol and dehydroabietic acid, with potential applications for perfumery and anti tumor/anti-inflammatory medications. Size-exclusion chromatography analysis showed that the weight-average molecular weight of the alkaline biodegraded lignin increased by 6.75-fold compared to the acidic method, resulting in a repolymerization of its molecular structure. Lignin repolymerization coincided with an increase in the relative abundance of dehydroabietic acid and isovanillyl alcohol, from 2.70 and 3.96% on day zero to 13.43 and 10.26% on 10th day. The results of the Fourier-transformed Infrared spectroscopy detected the presence of C = O bond and OH functional group associated with carboxylic acids in the acidic method. In the alkaline method there was a greater preponderance of signals related to skeletal aromatic structures, the amine functional group and the C – O – bond. Lignin biodegradation products from E. coli BL21(Lacc), under different initial pH conditions, demonstrated a promising potential to enlarge the spectrum of renewable products for biorefinery activities
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