A method to assess the eco-efficiency of a public bus transportation service

Brazilian Public Bus Transportation Service transports over 34.4 million passengers daily using approximately 107,000 urban buses. This service costs millions of dollars annually to the municipality and emits several pollutants to the atmosphere. Therefore, this paper proposes a method to assess the eco-efficiency of a Public Bus Transportation Service. The proposed method was tested in a medium-sized urban region in Brazil. Different scenarios representing changes in the vehicles engines and fuels were tested and analyzed. Six eco-efficiency indicators regarding emissions and fuel consumption were proposed to assess which mix of engines and fuels would bring the greatest eco-efficiency. The results were compared to targets based on Brazilian regulation and showed that the renewal of the fleet is necessary to meet the environmental targets, while also achieving fuel costs reduction.     

Flying into the future: A scenario-based analysis of carbon emissions from China's civil aviation

Aviation emissions will significantly affect climate change with the continued growth of the air transport. This study decomposes the drivers influencing China's civil aviation carbon emissions change in the period from 1985 to 2015. Emission trends are predicted using a Monte Carlo simulation. The results show a peak and reduction in the period between 2016 and 2030. Results also show that air transportation revenue growth is associated with increasing historical carbon emissions, while rising industry energy intensity significantly hampers carbon emissions reduction. The carbon intensity (CI) reduction goals were achieved in the different scenarios before 2020, but the carbon emissions peak target before 2030 can only be achieved under the technological breakthrough scenario (TBS). The reduction of air transport growth rate and promotion of new energy technologies are two essential strategies to reduce carbon emissions in the foreseeing future.     

A fuel surcharge policy for reducing road traffic greenhouse gas emissions

This paper proposes a car pricing policy based on fuel surcharges in substitution of car ownership taxes for reducing greenhouse gas emissions by cars. The aim of the proposed policy is to change some (fixed) costs of car use that are not perceived at each trip into (variable) costs. The amount of fuel surcharges and the effects of their application on fuel consumption and on GHG emissions are estimated by a model that is able to relate gasoline and diesel consumption with fuel prices. The effects of the proposed policy on fuel consumption and on GHG emissions are estimated for Italy. The results show that car users prefer to shift towards more efficient fuel vehicles than to public transport, producing a significant, but less than expected, reduction of GHG emissions.     

Reprint of “Green supply chain decisions – Case-based performance analysis from the food industry”

Environmental impacts, such as GHC emissions, have been introduced to supply chain management as an additional parameter to traditional cost, lead-time and on-time delivery. Supply chain management represents a significant source of decisions affecting the eco-efficiency of many products. This paper analyses cases from the food industry, mainly order-picking, transportation, warehousing, and distribution aspects from the greening point of view. Three case examples of decisions in supply chain design in the food industry are considered. The results show dependencies between performance measures. Finally, a framework of decisions and their impact on performance is presented.     

Exploring multiple eco-routing guidance strategies in a commuting corridor

The introduction of eco-routing systems has been suggested as a promising strategy to reduce carbon dioxide emissions and criteria pollutants. The objective of this study is to scrutinize the impacts of an eco-routing guidance system on emissions through the use of a case study in a commuting corridor. This research aims at assessing the potential environmental benefits in terms of different pollutant emissions. Simultaneously, it addresses the extent of variations in system travel time (S_TT) that each eco-routing strategy implies. The methodology consists of three distinct phases. The first phase corresponds to the adjustment of a microsimulation platform of traffic and emissions with empirical data previously collected. Second, to volume-emission-functions (VEF), developed based on the integrated modeling structure. Final, to different scenarios of traffic flow optimization performed at the network level based on a simplified assignment procedure. The results show that if the traffic assignment is performed with the objective to minimize overall impacts, then the total system environmental damage costs can be reduced up to 9% with marginal oscillations in total S_TT. However, if drivers are advised based on their own emissions minimization, total system emissions may be higher than under the standard user equilibrium flow pattern. Specifically, environmentally friendly navigation algorithms focused on individual goals may tend to divert traffic to roads with less capacity affecting the performance of the remaining traffic. This case study brings new insights about the difficulties and potentials of implementing such systems.     

The implications of environmental costs on air passenger demand for different airline business models

Various environmental measures, including both regulations and fiscal instruments, have been used at airports globally to reduce the impacts of aircraft noise as well as aircraft engine emissions. Internationally, it is recognized that the costs of environmental and social externalities of air transport must be internalized and paid for by the aviation industry and its users. The use of noise related charges or taxes, which theoretically should be based on their respective social costs, has been proved to be effective at some European airports. This research aims to investigate the impacts of environmental costs, through environmental charges, on air passenger demand for different airline business models. The paper presents the mathematical models measuring the social costs of aircraft noise and engine emissions as a basis for setting up environmental charges. Six intra-European short-haul routes in two city pairs, namely London–Amsterdam and London–Paris, are selected for the empirical analysis. The environmental charges are then hypothetically applied to airlines with two different business models, full service carriers (British Airways and Air France-KLM) and low cost airlines (EasyJet). The results show that the potential percentages of demand reduction for both leisure and business passengers would be higher for Easyjet's markets, although with less environmental cost per passenger.     

A tentative analysis of the impacts of an airport closure

This paper identifies the vulnerabilities of operations at Heathrow airport to a short airport closure. The system disruptions assessed are delays, flight rerouting or diversions to alternate airports, and flight cancellations. In addition, the impact on fuel consumption, and hence CO₂ emissions, is quantified using the Reorganized Air Traffic Control Mathematical Simulator Plus simulation model and the Advanced Emission Model tool. The results have implications for assessing how increased severe weather events associated with climate change may disrupt airport operations.     

Hinterland operations of sea ports do matter: Dry port usage effects on transportation costs and CO2 emissions

Decreasing carbon dioxide (CO₂) emissions is one of the most important tasks for the society in the 21st century. One possibility to decrease emissions originating from transportation is to utilize more rails instead of relying simply on road transportation. In the dry port concept an inland intermodal terminal is connected to a sea port using railways. This study analyzes impacts of dry ports in a Finnish context. We compare two different configurations: In the first one shippers drive directly to a sea port, while in the second one they use dry ports. The systems are evaluated by using discrete-event simulation. In the systems we are interested in two issues: (1) Level of CO₂ emissions, and (2) Costs to transport the goods in different configurations. We use different scenarios for future energy prices and estimate both the costs and CO₂ emission development in these scenarios. We also compare the results to a situation, where emissions are minimized instead of costs. Implications on larger scale are also discussed, for example in the Baltic Sea and North Sea area, where strict sulfur emission restrictions are seen to harm sea transport and increase concentration on small number of sea ports.     

A method for the estimation of greenhouse gas emissions based on road geometric design and its application to South Korea

South Korea has the tenth highest greenhouse gas (GHG) emissions worldwide, of which 16% originates from the road sector. Existing estimation methods of road GHG emissions have various limitations, such as low accuracy or the ability to only estimate GHG emissions within a limited area. Therefore, this study aimed to develop a methodology to estimate GHG emissions while considering various geometric designs of roads, including both vertical and horizontal alignment. The developed method is more objective and reliable than existing methodologies that consider only vertical alignment. First, Lamm's theory on travel speed profiles was applied to predict GHG emissions. Then, this study attempted to overcome the limited spatial estimation capacity of existing methods by considering upstream and downstream geometric design parameters simultaneously. Second, this study used the GHG operation mode extracted from the MOtor Vehicle Emission Simulator (MOVES), a modeling system that estimates emissions for mobile sources at the national, county, and project levels for criteria air pollutants, GHGs, and air toxicity. The operation mode includes vehicle type, fuel, and other factors, and is designed to estimate GHG emissions at 1-s intervals. Based on the results of the analysis, the effectiveness of the new method was compared to existing methods using an economic analysis (e.g., cost–benefits from the reduced emissions). This study presents a method for performing sensitive estimations of GHG emissions according to the geometric design of roads, which can be used to collect more accurate data on GHG emissions.     

Emissions and exposure costs of electric versus conventional vehicles: A case study in Texas

The emissions and human exposure impacts of electric vehicle (EV) adoption, especially in comparison to conventional gasoline- or diesel-powered engines, depend on numerous factors including geography, electricity generation, and fuel mix. Results of any analysis also vary depending on the nature of data collected and their level of aggregation by time or location. This paper combines several approaches to develop a robust estimate of these impacts specific to the state of Texas by considering marginal emissions by time of day, as well as location of vehicle and power plant emissions. The authors estimate health and other external costs of operating an EV in the state at approximately $62 per year, compared with an average of $136 for a passenger car powered by gasoline.     

Emissions trading for international aviation—an estimation of the economic impact on selected European airlines

International aviation is responsible for between 2.5% and 3% of anthropogenic carbon dioxide (CO₂) emissions that are partly held responsible for climate change. International aviation is not subject to any regulatory framework for the limitation of these emissions. From an economic point of view, the introduction of an emissions trading scheme would be an appropriate instrument to limit these emissions. This paper outlines the possibilities on how aviation could be included in existing emissions trading schemes and gives an overview on the current political discussion. It continues with an empirical estimation of the impacts on operating costs and transport demand for low cost, full service, holiday and regional airlines taking Ryanair, Lufthansa, Condor and Air Dolomiti as examples, under three different design options for an emissions trading scheme. Finally, conclusions about the impacts on intra-European and worldwide airline competition are drawn.     

A hybrid multi-objective approach to capacitated facility location with flexible store allocation for green logistics modeling

We propose an efficient evolutionary multi-objective optimization approach to the capacitated facility location–allocation problem (CFLP) for solving large instances that considers flexibility at the allocation level, where financial costs and CO₂ emissions are considered simultaneously. Our approach utilizes suitably adapted Lagrangian Relaxation models for dealing with costs and CO₂ emissions at the allocation level, within a multi-objective evolutionary framework at the location level. Thus our method assesses the robustness of each location solution with respect to our two objectives for customer allocation. We extend our exploration of selected solutions by considering a range of trade-offs for customer allocation.     

Assessment of transport emissions impact and the associated social cost for Chengdu,China

Chengdu, the capital city of Sichuan province, is the fourth biggest city in China with over 15 million residents and 3.4 million vehicles. In Chengdu, transport and other mobile sources accounted for over 27% of the city's PM_2.5 emissions (CDEPB, 2016), posing negative impacts on public health, local environment, and the climate. This study estimated impacts from transport-related emissions (CO₂, CH₄, N₂O, PM₁₀, PM_2.5, NO_X, SO_X, CO, and HC) and evaluated the associated social cost for Chengdu from 2005 to 2013. The study also assessed the city's transport performance in terms of its eco-efficiency with the socioeconomic and environmental concerns. The activity-based methodology was adopted to produce the emission inventories, while utilizing meta-analysis and localizing the emission social cost factors based on Chengdu's economic and demographic reality to support social cost assessment. The study marks the first attempt in literature to evaluate Chengdu's transport emission social cost. The following were observed in the study: (i) in 2013, the social cost of all transport emissions in Chengdu was around US$3 billion, with the lowest estimate of US$449 million and the highest estimate of US$4.7 billion; (ii) trucks, private cars, and motorcycles were the major contributors, while NO_X, PM_2.5, and CO were the key pollutants to public health; (iii) if GHGs (CO₂, CH₄, and N₂O) were excluded, the upper range of social cost of transport air pollutants would be from US$2.4 billion to US$4.1 billion, or 1.6%–2.8% of the Chengdu's GDP.     

The historical fuel efficiency characteristics of regional aircraft from technological, operational, and cost perspectives

To develop approaches that effectively reduce aircraft emissions, it is necessary to understand the mechanisms that have enabled historical improvements in aircraft efficiency. This paper focuses on the impact of regional aircraft on the US aviation system and examines the technological, operational and cost characteristics of turboprop (TP) and regional jet (RJ) aircraft. Regional aircraft are 40–60% less fuel efficient than their larger narrow- and wide-body counterparts, while RJs are 10–60% less fuel efficient than TPs. Fuel efficiency differences can be explained largely by differences in aircraft operations, not technology. Direct operating costs per revenue passenger kilometer are 2.5–6 times higher for regional aircraft because they operate at lower load factors and perform fewer miles over which to spread fixed costs. Further, despite incurring higher fuel costs, RJs are shown to have operating costs similar to TPs when flown over comparable stage lengths.     

The economic benefits and environmental costs of airport operations: Taiwan Taoyuan International Airport

This paper compares the economic gains from airports with some of the environmental costs of their operations. The economic effects are divided into direct, indirect, and induced impacts, and the direct impact into employment and income generated by the operation of an airport; while the indirect and induced impacts are the income generated in the supply chain. We focus on evaluating employment benefits and the social costs of both aircraft noise and engine emissions, using Taiwan Taoyuan International Airport as a case study. The results indicate that the economic benefits generated from the operations of the airport outweigh the negative side effects.     

Environmental costs in European aviation

This paper presents estimates of environmental costs in a set of 36 European airline markets. Cost are calculated for noise, air pollution and accident risk using data on aircraft emissions, exposure-response parameters and economic valuation of environmental goods. The ‘medium value’ cost estimate is 0.0201ECU per passenger-km. This result suggests that environmental costs represent only a small fraction (2.5%) of the internal cost of aviation as measured by the average ticket price. Noise costs are the dominant environmental cost at some 75% of the cost total. The medium estimates are sensitive to changes in the various assumptions in the pathways: a low and high estimate are three times lower and five times higher, respectively, than the medium estimate. The study further suggests that there are environmental economies of scale in air transport and that Chapter 2 aircraft are about a factor four more environmentally costly than Chapter 3 aircraft.     

Design and planning for green global supply chains under periodic review replenishment policies

We quantify the impact of jointly optimizing strategic network design and tactical inventory planning on the cost and CO₂ emissions of multi-echelon logistics networks. The obtained insights indicate that longer optimized replenishment cycles reduce a node’s transportation cost and CO₂ emissions but increase its inventory costs. Moreover, under a fixed replenishment cycle, a node’s service level increases when supplied by a satellite warehouse. Finally: (i) the costs of implementing optimal green network design decisions could be misleading if inventory planning is neglected, (ii) greening of supply chains could become expensive, (iii) current legislative CO₂ ton prices hardly influence logistics networks.     

Development of air pollutant emission factors under real-world truck driving cycle

The truck driving cycle was developed in Thailand using actual speed-time profile from trucks in suburban area. Driving data were separated into micro trips and the representative driving cycle was selected by matching micro trips statistics and target statistics. The Performance Value (PV) was considered for selecting the representative driving cycle. This selected driving cycle was then used as input data for estimating emission factors of 4 air pollutants and 3 greenhouse gases by the International Vehicle Emission (IVE) model. Results were then compared with emission factors developed using the European Transient Cycle (ETC). Additionally, a comparison was made between emission factors calculated in this study and direct measurements of emissions from truck driven on chassis dynamometer under the European driving cycle. Comparison results revealed that CO, NO_x and CO₂ emission factor were about 2.05, 2.24 and 1.78 times lower than those obtained from direct measurements. PM emission factor was about 0.89 times higher than measured data. This study confirms the need to considered actual fleets and characteristics of vehicular sources when calculating their emission rates for further use in development of emission inventory.     

Environmental footprint of road freight: Case studies from Switzerland

Current Swiss policy aiming to reduce the environmental footprint of heavy vehicles is presented. The environmental footprint of 46 heavy vehicle cases defined as dynamic load, noise, vibration and gaseous emissions is measured based on criteria set by the European project Eureka Logchain footprint. These parameters were measured for freight vehicles selected from the traffic stream and were compared to the criteria set up as a result of current Swiss policy. Results show that parameters that are currently controlled and their reduction encouraged such as gaseous emissions, axle loads and gross weight are indeed below or close to acceptable limits. However, other important parameters such as tyre pressure and noise remain higher than acceptable limits. In order to encourage the operation of vehicles with a low total environmental footprint parameters need to be set and controlled systematically.     

白洋港铁水联运车船直取模式研究

白洋港作为长江三峡的核心内陆港,是工业输出港、翻坝转运港和西部出海港,主要服务于白洋工业园区,担当西北地区物流陆水联运的作用。为实现白洋港铁水联运的无缝衔接,在阐述白洋港铁水联运模式及作业流程的基础上,针对白洋港既有铁水联运模式存在的问题,提出白洋港铁水联运车船直取模式,从车船直取模式设施布局及作业流程进行分析,达到压缩无效作业时间、提高白洋港铁水联运效率、释放技术站作业能力等效果,实现白洋港铁水联运效率的提升。