Search Results (24)

This paper addresses the underrepresentation of traffic activity in Life Cycle Assessment (LCA) practice despite its critical influence on the energy and environmental footprint of both electrified and conventional vehicles. To bridge this gap, the paper proposes a new framework that enhances the integration of traffic dynamics into fleet LCAs while maintaining computational simplicity. The approach combines Macroscopic Fundamental Diagrams (MFDs), which estimate network-level traffic performance, with an average-speed-based emissions model to evaluate on-road energy use and emissions performance of traffic. This quantification is further extended by applying life cycle inventory emission factors to account for upstream and downstream impacts, including energy production, vehicle manufacturing, and end-of-life treatment. The framework is demonstrated through a case study involving urban traffic networks in Zurich and Thessaloniki. Results illustrate the method’s capacity to evaluate multiple vehicles within realistic flow scenarios and adaptability to variable traffic conditions, offering a practical and scalable tool for improved energy and environmental assessment of road transport fleets. Full article

Airport operations significantly contribute to air pollution in their vicinity through various sources, including aircraft activities—particularly taxiing and take-off—as well as ground support equipment, service vehicles, and maintenance work. Since emissions from aircraft engines represent the primary pollution source at airports, it is essential to reduce emissions at every phase of the LTO (landing and take-off) cycle to improve local air quality and promote environmental sustainability. Given the research gap in emission analysis, a comprehensive LCA framework for airport pushback and taxi operations is proposed, integrating tow truck propulsion, a taxiing strategy, and fleet management. Given the complexity of the issue, the authors first decided to investigate emissions from taxiing operations using tow trucks with different powertrains. The analyses performed were considered preliminary and a starting point for exploring emissions during taxiing operations at airports. Typically, aircraft are pushed back from the apron and then taxi under their own power using both engines at approximately 7% of maximum thrust. To substantially reduce exhaust emissions, external towing vehicles can be employed to move aircrafts from the apron to the runway. This study evaluates the potential for emission reductions in CO₂ and other harmful compounds such as CO, HC, NO_x, and PM by using electric towing vehicles (ETVs). It also compares emissions from different taxiing methods: full-engine taxiing, single-engine taxiing, ETV-assisted taxiing, and taxiing using diesel and petrol-powered tow vehicles. The analysis was conducted for Warsaw and Poznań airports. Three aircraft types—the most commonly operating at these airports—were selected to assess emissions under various taxiing scenarios. The results show that using electric towing vehicles can reduce CO and NO_x emissions to nearly zero compared to other methods. Interestingly, CO emissions from full-engine taxiing were lower than those from petrol-powered towing, although the Embraer 195 showed the highest CO emissions among the selected aircrafts. HC emissions were lowest for the A321neo and also relatively low for the diesel towing vehicle. The use of electric tow trucks significantly reduces CO₂ emissions: only 2.8–4.4 kg compared to 380–450 kg when taxiing with engines. This research highlights the critical role of sustainable ground operations in reducing harmful emissions and underscores the importance of integrating sustainability into airport taxiing practices. Full article

At present, the decarbonization of the public transport sector plays a key role in international and regional policies. Among the various energy vectors being considered for future clean bus fleets, green hydrogen and electricity are gaining significant attention thanks to their minimal carbon footprint. However, a comprehensive Life Cycle Assessment (LCA) is essential to compare the most viable solutions for public mobility, accounting for variations in weather conditions, geographic locations, and time horizons. Therefore, the present work compares the life cycle environmental impact of different powertrain configurations for urban buses. In particular, a series hybrid architecture featuring two possible hydrogen-fueled Auxiliary Power Units (APUs) is considered: an H2-Internal Combustion Engine (ICE) and a Fuel Cell (FC). Furthermore, a Battery Electric Vehicle (BEV) is considered for the same application. The global warming potential of these powertrains is assessed in comparison to both conventional and hybrid diesel over a typical urban mission profile and in a wide range of external ambient conditions. Given that cabin and battery conditioning significantly influence energy consumption, their impact varies considerably between powertrain options. A sensitivity analysis of the BEV battery size is conducted, considering the effect of battery preconditioning strategies as well. Furthermore, to evaluate the potential of hydrogen and electricity in achieving cleaner public mobility throughout Europe, this study examines the effect of different grid carbon intensities on overall emissions, based also on a seasonal variability and future projections. Finally, the present study demonstrates the strong dependence of the carbon footprint of various technologies on both current and future scenarios, identifying a range of boundary conditions suitable for each analysed powertrain option. Full article

The transportation sector is considered the number one consumer of tires worldwide. At present, 1.1 billion vehicles relying on this industry, although this number is increasing significantly following supply chain demands and the rapid economic growth. Among the main selection standards for fleet-operating enterprises are the quality, durability, and sustainability of tires, in efforts to ensure efficiency and safety for continuous operations. Lifecycle assessments (LCAs) are the optimal solution to optimize tire usage for extended performance and increased lifespan. In this paper, we developed a prediction model aiming at managing tires during the middle-of-life phase (use phase) while minimizing the negative environmental impact. Full article

The aim of this article is to assess the sale structure impact of selected, popular brands of passenger vehicles on total CO₂ emissions in the context of the energy transition in the transport sector. A detailed analysis was conducted of the projected sales of gasoline-, diesel-, hybrid-, as well as electric-powered vehicles over the years 2021–2028. Based on the available empirical data, a mathematical model was developed to estimate emissions over the entire life cycle of vehicles, taking into account the unit carbon footprint of each type of drivetrain and the expected number of vehicles sold. The results indicate a gradual decline in total CO₂ emissions during the analyzed period, mainly due to the increasing share of alternative drivetrains. Despite the growth in electric vehicle sales, their impact on emission reductions remains limited due to the long lifespan of conventional vehicle fleets. The article concludes with a proposal to expand the LCA model to include regional, energy, and recycling components, which could help in formulating more effective climate policies. Full article

Fast patrol boats account for a large number among the numerous vessels used in naval fleets. Owing to their operational characteristics, which involve relatively high speeds, they contribute to emissions significantly. This study presents an optimized design concept for a diesel–battery hybrid electric propulsion system integrated into the general ship design process for fast patrol boats. The optimization design uses mixed-integer linear programming to determine the most eco-friendly shares ratio of battery and diesel usage while satisfying high-endurance operational scenarios. A shares ratio of 1.259 tons of diesel to 2.88 tons of batteries was identified as the most eco-friendly configuration capable of meeting a 200-nautical-mile operational scenario at a maximum speed of 35 knots for the selected case study. A quantitative comparison through a global warming potential (GWP) analysis was conducted between conventional diesel propulsion systems and the designed diesel–battery hybrid electric propulsion system, using a life-cycle assessment (LCA) standardized under the ISO framework. The analysis confirmed that the optimized hybrid propulsion system can achieve a GWP reduction of approximately 7–9% compared with conventional propulsion systems. Few studies have applied LCA in this field, and the application of batteries as hybrid secondary energy sources is viable and sustainable for high-endurance scenarios. Full article

Sustainable mobility in university environments presents both a challenge and an opportunity to reduce environmental impact and promote energy efficiency. This study assesses the feasibility of implementing electric buses in the internal transportation system of the Federal University of Paraíba (UFPB), considering environmental, economic, and operational aspects. The analysis demonstrates that transitioning to this model can lead to a significant reduction in greenhouse gas (GHG) emissions, noise pollution mitigation, and optimization of operational costs throughout the vehicle’s life cycle. The study examines technical, structural, and financial factors, emphasizing the necessary infrastructure, academic community acceptance, and the economic viability of the project, as well as the strategic advantage of integrating the electric fleet with photovoltaic energy generation. The key highlights of this research include: (i) Sustainability and energy efficiency, emphasizing a reduction of up to 52.52% in CO₂ emissions when vehicles are powered by photovoltaic energy in an LCA context, alongside improvements in air quality and noise pollution mitigation. (ii) Economic feasibility analysis, comparing operational and maintenance costs between electric and conventional diesel buses, evaluating the financial viability and potential return on investment. (iii) Infrastructure and implementation challenges, addressing the need for charging stations, adaptation of UFPB’s infrastructure, and financing models, including government subsidies and strategic partnerships. (iv) Impact on the academic community, analyzing student and staff perceptions and acceptance of fleet electrification and the promotion of sustainable practices. (v) Future projections and replicability, exploring trends in the sustainable transportation sector, as well as the potential expansion of the electric fleet and its integration with energy storage systems. The results indicate that adopting electric buses at UFPB can position the institution as a benchmark in sustainable mobility, serving as a replicable model for other universities and contributing to carbon emission reduction and modernization of university transportation. Full article

Background: This study applied levelized cost of hydrogen (LCOH) and environmental cost accounting techniques to evaluate the feasibility of producing green hydrogen (GH₂) via alkaline electrolysis for use in a bus fleet in Fortaleza, Brazil. Methods: A GH₂ plant with a 3 MW wind tower was considered in this financial project. A sensitivity analysis was conducted to assess the economic viability of the project, considering the influence of production volume, the number of electrolysis kits, financing time, and other kay economic indices. Revenue was derived from the sale of by-products, including green hospital oxygen (GHO₂) and excess wind energy. A life cycle assessment (LCA) was performed to quantify material and emission flows throughout the H₂ production chain. A zero-net hydrogen price scenario was tested to evaluate the feasibility of its use in urban transportation. Results: The production of GH₂ in Brazil using alkaline electrolysis powered by wind energy proved to be economically viable for fueling a hydrogen-powered bus fleet. For production volumes ranging from 8.89 to 88.9 kg H₂/h, the sensitivity analysis revealed high economic performance, achieving a net present value (NPV) between USD 19.4 million and USD 21.8 million, a payback period of 1–4 years, an internal rate of return (IRR) of 24–90%, and a return on investment (ROI) of 300–1400%. The LCOH decreased with increased production, ranging from 56 to 25 USD/MWh. Over the project timeline, GH₂ production and use in the bus fleet reduced CO₂ emissions by 53,000–287,000 t CO₂ eq. The fuel cell bus fleet project demonstrated viability through fuel cost savings and revenue from carbon credit sales, highlighting the economic, social, and environmental sustainability of GH₂ use in urban transportation in Brazil. Full article

The FuelEU Maritime Regulation, part of the European Union’s (EU’s) Fit for 55 initiative, aims to achieve significant reductions in greenhouse gas (GHG) emissions within the maritime sector. This study assesses the feasibility of alternative fuels for the Estonian pilot fleet using a Well-to-Wake (WtW) life cycle assessment (LCA) methodology. Operational data from 18 vessels, sourced from the Estonian State Fleet’s records, were analyzed, including technical specifications, fuel consumption patterns, and operational scenarios. The study focused on marine diesel oil (MDO), biomethane, hydrogen, biodiesel, ammonia, and hydrotreated vegetable oil (HVO), each presenting distinct trade-offs. Biomethane achieved a 59% GHG emissions reduction but required a volumetric storage capacity up to 353% higher compared to MDO. Biodiesel reduced GHG emissions by 41.2%, offering moderate compatibility with existing systems while requiring up to 23% larger storage volumes. HVO demonstrated a 43.6% emissions reduction with seamless integration into existing marine engines. Ammonia showed strong potential for long-term decarbonization, but its adoption is hindered by low energy density and complex storage requirements. This research underscores the importance of a holistic evaluation of alternative fuels, taking into account technical, economic, and environmental factors specific to regional and operational contexts. The findings offer a quantitative basis for policymakers and maritime stakeholders to develop effective decarbonization strategies for the Baltic Sea region. Full article

Life Cycle Assessment (LCA) methodology can be used to quantitatively assess the greenhouse gas emissions of low- or zero-carbon marine alternative fuels throughout their life cycle (from well to wake) and is an important basis for ensuring a green energy transition in the shipping industry. This paper first clarifies the trends and requirements of low-carbon development in shipping and introduces the major ship emission reduction technologies and evaluation methods. Next, the characteristics of various alternative marine fuels (i.e., LNG, hydrogen, methanol, ammonia, and biofuels) are comprehensively discussed and analyzed in terms of production, storage, transportation, and ship applications. In addition, this work provides a comprehensive overview of LCA methodology, including its relevant standards and assessment tools, and establishes a framework for LCA of marine alternative fuels. On this basis, a literature review of the current research on LCA of marine alternative fuels from the perspectives of carbon emissions, pollution emissions, and economics is presented. The case review covers 64 alternative-fueled ships and 12 groups of fleets operating in different countries and waters. Finally, this paper discusses the main shortcomings that exist in the current research and provides an outlook on the future development of LCA research of marine alternative fuels. Full article

With rapid advancements in unmanned aerial vehicle (UAV) technology, its integration into logistics operations has emerged as a promising solution for improving efficiency and sustainability. Among the emerging solutions, a collaborative delivery model involving drones and trucks addresses last-mile delivery challenges by leveraging the complementary strengths of both modes of transport. However, evaluating the environmental and economic impacts of this transportation mode requires a systematic framework to capture its unique characteristics and minimize environmental impacts and costs. This paper investigates the Parallel Drone Scheduling Traveling Salesman Problem (PDSTSP) to evaluate the environmental and economic sustainability of a collaborative drone-truck delivery system. Specifically, a mathematical model for this delivery system is developed to optimize joint delivery operations. Environmental impacts are assessed using a comprehensive Life Cycle Assessment (LCA), including emissions and operational noise, while a Life Cycle Cost Analysis (LCCA) quantifies economic performance across five cost dimensions. Sensitivity analysis explores factors such as delivery density, traffic congestion, and wind conditions. Results show that, compared to the electric vehicle fleet, the proposed model achieves an approximate 20% reduction in carbon emissions, while delivering a 20–30% cost reduction relative to the fuel truck fleet. Drones’ efficiency in short-distance deliveries alleviates trucks’ load, cutting environmental and operational costs. This study offers practical insights and recommendations for implementing drone-truck parallel delivery systems, particularly in high-demand density areas. Full article

(1) Background: A strategic approach to managing and evolving the bus fleet is essential for optimizing public transportation, improving service efficiency, meeting future demands, and incorporating environmentally friendly technologies. However, country-specific data on fleet composition and evolution are often lacking despite their importance in evaluating technological impacts on the environment, passenger comfort, and driver working conditions. This report describes the creation of the inventory of the Swiss bus fleet and analyzes technological developments in bus vehicles from 1940 to 2022. (2) Methods: We collected the data through a comprehensive mapping study and validated it with Swiss bus companies and experts from the Federal Office of Transport. Vehicle approval forms were used to extract technical data. Buses were sorted by brand and model. For each bus model, 58 technical characteristics were documented in a database. A latent class analysis (LCA) was conducted to classify the buses according to their technological characteristics. (3) Results: The inventory comprises 891 bus models, classified into four groups representing different generations. The predominance of thermal buses and the emergence of hybrid and electric buses since 2010 were noticed. (4) Conclusion: This inventory tracks bus technology evolution and highlights potential implications for driver occupational exposure and environmental impact assessment. Full article

Among the economic sectors, mobility is showing significant environmental impacts, especially in the use phase of vehicles. By substituting fossil-fuelled propelling systems, environmental impacts such as the Global Warming Potential (GWP) can be reduced. The use of properly designed light electric vehicles (LEVs) significantly reduces further environmental impacts, as well as maintenance costs, which are relevant for a circular economy. For example, the use of low-voltage (42 V) propelling systems enables the maintenance of LEVs in a broader range of existing bicycle workshops. Regarding the environmental impacts, the described LCA results indicate the advantage of LEVs compared with EVs and ICVs, e.g., vehicle weight is found to be a main factor related to environmental impact for each type of vehicle. This implies a reduced need for battery capacity and lower emissions of particulate matter from tire and break abrasion. This study aims to present the application potential of LEVs and the related reduction in environmental impacts. Anonymised inventory lists of municipal vehicle fleets are analysed for quantifying the substitution potential of LEVs in specific use cases. For this purpose, the use phase of vehicles is analysed with a focus on product design for repair and recycling and supplemented by the results of a comparative environmental impact assessment of internal combustion engine vehicles (ICEVs), electric vehicles (EVs), and LEVs. The comparison is made on the premise of similar application requirements. These specifications are the ability of each of the vehicles to transport a maximum of three persons (driver included) or one driver and 250 kg of cargo in 3 m³ over a daily distance of 100 km in urban areas. On this basis, the municipal environmental benefits derived from substituting small vehicles in the form of ICEVs and EVs with LEVs are assessed. The results show that in the field of municipal mobility, a relevant number of conventional small vehicles can be substituted with LEVs. The environmental impacts in categories of the highest robustness level, RL I, that is, Global Warming Potential, fine dust emissions, and Ozone Depletion Potential, can be reduced by LEVs by 50% compared with EVs and by over 50% compared with ICEVs. The strong influence of vehicle weight on the abrasive conditions of tires and brakes is considerable, as shown by reduced fine dust emissions. Full article

In order to reduce the environmental impacts caused by the transport sector, autonomous and electrified on-the-road modular vehicles (otrm) could be a solution. By separating the drive unit from the transport unit, they enable use cases for various transport tasks and reduce individual and motorized transport and its generated emissions. Therefore, the goal of this study is to assess the environmental impacts from cradle to grave by applying the LCA methodology for a defined otrm—the U-Shift—vehicle fleet considering a specific use case relative to a reference vehicle fleet. The results indicate that the U-Shift fleet reduces the life cycle environmental impacts in a range of 3–28% for all of the seven impact categories, which are analyzed in detail. While emissions from the use phase are similar, U-Shift has an environmental benefit in the production phase due to a low amount of resource-intensive driveboards. Considering the early development stage of U-Shift, several measures are discussed, addressing the material and configuration aspects of the vehicles as well as optimized use case applications, which promise further impact-reduction potential. Full article

In Korea, fishing boats account for 65,452 out of 71,174 coastal ships, and aging ships are a leading cause of environmental problems and economic loss. To solve this problem, the government has enacted a policy to promote the development and distribution of environmental vessels. Electric propulsion systems and hybrid systems are suggested as alternatives. However, to study whether this hybrid system is environmentally friendly, a system for measuring the performance of conventional diesel-powered ships was developed and measured. A case study applying the battery hybrid system was analyzed through a Matlab/Simulink simulation, and the effect of reducing the carbon dioxide emissions by 7.6% was verified. In addition, comparing with a case where the load-sharing optimal control was introduced, we proved that the carbon dioxide reduction with the controller was 10.7%. By applying the results of this study to various countries with different fuel production processes through the LCA technique, it was confirmed that the battery hybrid system is eco-friendly from the energy production stage, rather than unconditionally, according to the national power production method. Additional research is needed to reflect the aging trend of the entire fleet and to create a detailed category classification through future research. Full article