Impact of convenient away-from-home charging infrastructure

This work uses market analysis and simulation to explore the potential impact of workplace and similarly convenient away-from-home charging infrastructure (CAFHCI) in reducing US light duty vehicle (LDV) petroleum use and greenhouse gas emissions. The ParaChoice model simulates the evolution of LDV sales, fuel use, and emissions through 2050, considering consumer responses to different options of electric range extension made available through CAFHCI, fraction of the population with access, and delay in infrastructure implementation. Results indicate that providing a greater fraction of the population access to CAFHCI at level 1 charging rates for a full workday (∼16–20 miles of range extension) may lead to more petroleum use reduction than providing level 2 charging to a lesser fraction. This result holds even considering the fraction of the population without at-home charging. 2050 battery electric vehicle sales increase 40% (85%) if the entire population is guaranteed daily access to one full workday of level 1 CAFHCI (half a workday of level 2, ∼80 miles of range extension). Plug-in hybrid sales increase when CAFHCI enables range extension below 20–40 miles/day, most significantly in households without at-home charging capability. Faster CAFHCI may decrease plug-in hybrid sales as less expensive BEVs become attractive to a greater fraction of the market.     

GHG emissions in daily travel and long-distance travel in Germany – Social and spatial correlates

There is considerable research on the climate effects of daily travel, including research on the spatio-temporal and socioeconomic impact factors of daily travel and associated climate change effects. However, this is less true with respect to long-distance trips. This paper uses national transport survey data from Germany to point out differences in GHG emissions related to demographic, socioeconomic and spatial characteristics for daily and long-distance travel. Daily travel and long-distance travel are investigated simultaneously and separately using Logit and OLS regressions. The results show that transport-related GHG emissions from long-distance trips and daily trips are affected by sociodemographics in largely the same direction. In contrast, spatial attributes, like municipality size or density grade of the region, show a different picture. Per capita emissions in rural and suburban areas are higher for daily trips, but lower for long-distance trips than emissions caused by urban residents. While we cannot rule out the possibility of residential self-selection, our findings challenge the idea that compact urban development may help reduce CO₂ emissions once long-distance trips are taken into account.     

Effectiveness of vehicle weight enforcement in a developing country using weigh-in-motion sorting system considering vehicle by-pass and enforcement capability

Vehicle overloading has been identified as one of the major contributors to road pavement damage in Malaysia. In this study, the weigh-in-motion (WIM) system has been used to function as a vehicle weight sorting tool to complement the exsiting static weigh bridge enforcement station. Data collected from the developed system is used to explore the effectiveness of using WIM system in terms of generating more accurate data for enforcement purposes and at the same time improving safety and reducing the number of vehicle weight violations on the roads. This study specifically focus on the effect of vehicle by-pass and static weigh station enforcement capability on the overall effectiveness of vehicle weight enforcement system in a developing country. Results from this study suggest that the WIM system will significantly enhance the effectiveness and efficiency of the current vehicle weight enforcement, thus generating substantial revenue that would greatly off-set the current road maintenance budget that comes from tax payers money. If there is substantial reduction in overloaded vehicles, the public will still gain through reduction in road maintenance budget, less accident risks involving heavy trucks, and lesser greenhouse gases (GHGs) emissions.     

Exploring the trade-off between greenhouse gas emissions and travel time in daily travel decisions: Route and departure time choices

This study analyzes the problem of conflicting travel time and emissions minimization in context of daily travel decisions. The conflict occurs because the least travel time option does not always lead to least emissions for the trip. Experiments are designed and conducted to collect data on daily trips. Random parameter (mixed) logit models accounting for correlations among repeated observations are estimated to find the trade-off between emissions and travel time. Our results show that the trade-off values vary with contexts such as route and departure time choice scenarios. Further, we find that the trade-off values are different for population groups representing male, female, individuals from high income households, and individuals who prefer bike for daily commute. Based on the findings, several policies are proposed that can help to lower greenhouse gas (GHG) emissions from transportation networks. This is one of the first exploratory studies that analyzes travel decisions and the corresponding trade-off when emissions related information are provided to the road users.     

城市轨道交通运营企业温室气体核算方法研究

通过分析城市轨道交通运营企业能源消费结构,确定企业温室气体排放种类,掌握温室气体排放结构,划定温室气体核算的组织边界与运营边界。通过对比研究国内外通用温室气体核算标准,结合城市轨道交通运营企业自身特点,提出轨道交通运营企业温室气体核算步骤与核算方法。     

Comparison of energy demands of drone-based and ground-based parcel delivery services

Drones are one of the most intensively studied technologies in logistics in recent years. They combine technological features matching current trends in transport industry and society like autonomy, flexibility, and agility. Among the various concepts for using drones in logistics, parcel delivery is one of the most popular application scenarios. Companies like Amazon test drones particularly for last-mile delivery intending to achieve both reducing total cost and increasing customer satisfaction by fast deliveries. As drones are electric vehicles, they are also often claimed to be an eco-friendly mean of transportation.In this paper an energy consumption model for drones is proposed to describe the energy demand for drone deliveries depending on environmental conditions and the flight pattern. The model is used to simulate the energy demand of a stationary parcel delivery system which serves a set customers from a depot. The energy consumed by drones is compared to the energy demand of Diesel trucks and electric trucks serving the same customers from the same depot.The results indicate that switching to a solely drone-based parcel delivery system is not worthwhile from an energetic perspective in most scenarios. A stationary drone-based parcel delivery system requires more energy than a truck-based parcel delivery system particularly in urban areas where customer density is high and truck tours are comparatively short. In rather rural settings with long distances between customers, a drone-based parcel delivery system creates an energy demand comparable to a parcel delivery system with electric trucks provided environmental conditions are moderate.     

Exploring the link between the neighborhood typologies,bicycle infrastructure and commuting cycling over time and the potential impact on commuter GHG emissions

This paper investigates the evolution of urban cycling in Montreal, Canada and its link to both built environment indicators and bicycle infrastructure accessibility. The effect of new cycling infrastructure on transport-related greenhouse gas (GHG) emissions is then explored. More specifically, we aim at investigating how commuting cycling modal share has evolved across neighborhood built-environment typologies and over time in Montreal, Canada. For this purpose, automobile and bicycle trip information from origin–destination surveys for the years 1998, 2003 and 2008 are used. Neighborhood typologies are generated from different built environment indicators (population and employment density, land use diversity, etc.). Furthermore, to represent the commuter mode choice (bicycle vs automobile), a standard binary logit and simultaneous equation modeling approach are adopted to represent the mode choice and the household location. Among other things, we observe an important increase in the likelihood to cycle across built environment types and over time in the study region. In particular, urban and urban-suburb neighborhoods have experienced an important growth over the 10 years, going from a modal split of 2.8–5.3% and 1.4–3.0%, respectively. After controlling for other factors, the model regression analysis also confirms the important increase across years as well as the significant differences of bicycle ridership across neighborhoods. A statistically significant association is also found between the index of bicycle infrastructure accessibility and bike mode choice – an increase of 10% in the accessibility index results in a 3.7% increase in the ridership. Based on the estimated models and in combination with a GHG inventory at the trip level, the potential impact of planned cycling infrastructure is explored using a basic scenario. A reduction of close to 2% in GHG emissions is observed for an increase of 7% in the length of the bicycle network. Results show the important benefits of bicycle infrastructure to reduce commuting automobile usage and GHG emissions.     

Analyzing the effects of Gas-to-Liquid (GTL) diesel blending on the efficiency and emissions of petroleum refineries and transport fuels in the U.S. and Europe

The transport sector is fast changing with demand for distillates increasing amidst declining gasoline consumption in many markets especially in the developed world. Increasingly refineries are stretched to operate less efficiently and this is manifested through a drop in efficiency as a consequence of increasing diesel production via less efficient routes, particularly on the marginal barrel of diesel. It has been suggested that this decline in diesel production efficiency, as the ratio of gasoline to diesel (G/D) production drops, can partly be mitigated through the use of Gas-to-Liquid (GTL) diesel. In this paper we adopted refinery Linear-Programming models to represent the refining system in Europe as well as a district in the U.S. to investigate the effects of increased availability of GTL diesel to a refiner on the energy efficiency and GHG emissions of refineries. Here we showed that indeed there is an improvement in diesel production efficiency with increasing GTL concentrations, but this efficiency gain (<0.5%) is insufficient to counteract the higher energy consumption and emissions associated with the production of GTL, thus leading to an overall decline in life cycle efficiency (up to 5%), and an increase in life cycle GHG emissions (up to 2%).     

国际海运温室气体（GHG）减排浅析

以《联合国气候变化框架公约》（UNFCCC）为主要背景简要介绍全球温室气体排放现状、相关机制及面临的问题,进而对国际海事组织（IMO）在海运温室气体排放方面所采取的措施加以分析,最后结合国情对我国海运温室气体减排提出参考建议。     

海运温室气体减排市场机制ETS和GHG FUND的比较研究

海运温室气体排放交易机制(ETS)和基金机制(GHG FUND)是用于海运温室气体减排的2个代表性市场机制.为深入了解这2大机制,对其运行机理、减排效果、运行成本,以及新增碳排放成本进行了深度的解剖和定量分析;指出了机制设计中的不确定性以及对发展中国家、不同运输方式间竞争的不公平性.认为现有设计框架下的ETS和GHG FUND机制作为海运业市场减排机制方案并不妥当,海运业应该在寻求技术和营运的措施减排方面做更多的努力.