The transition to zero-emission buses in public transport – The need for institutional innovation

Zero-emission buses (ZEBs) are considered a vital element in the transition to a more sustainable (urban) transport system. Both battery-electric and hydrogen fuel cell buses do however face significant barriers to large-scale implementation. These barriers, e.g. high investment costs and limited driving range, are generally regarded as exogenous technological barriers which are beyond the sphere of influence of actors in the public transport sector. In this paper we question this assumption and therefore we look at the role of institutions in public bus transport. Based on a series of interviews with stakeholders in the Dutch public transport sector we argue that various regulative, normative, and cognitive institutions discourage the use of zero-emission buses in public transport. We conclude with several suggestions for institutional innovation to increase the chances for these buses.     

Communicating transportation carbon dioxide emissions information: Does gender impact behavioral response?

General concern and knowledge on climate change have been increasingly studied over the past decades. Gender differences have been found for general environmental concern and knowledge, but mixed findings exist with respect to climate change. In transportation, research has examined potential relations between environmental attitudes and transportation behavior, with mixed findings as well. Recently, the use of carbon dioxide (CO₂) emissions information to influence choice has been tested with women being found more willing to pay to reduce their personal impacts, suggesting that women are either more willing to change or that their response to information on climate change is stronger. However, those studies used CO₂ mass and studies that examined understanding of CO₂ information as a mass have found that people struggle to understand it. If concern and knowledge about climate change differ amongst individuals, then, according to theories such as the Transtheoretical Model, the type of information used to motivate choices is likely important. Using a unique data set (n = 236) it is possible to take a first look at how gender might affect concern, knowledge, and action in terms of transportation and climate change. Further, it is also possible to examine behavioral responses to transportation climate change information. Finally, an empirical analysis is conducted of the effect of how the information is presented might differ by gender. Thus, this work aims to investigate whether gender differences might contribute to the explanation of individual behavioral responses (from concern to action) in a transportation climate change context.     

Environmental life-cycle assessment of transit buses with alternative fuel technology

The paper presents a life-cycle assessment of costs and greenhouse gas emissions for transit buses deploying a hybrid input-output model to compare ultra-low sulfur diesel to hybrid diesel-electric, compressed natural gas, and hydrogen fuel-cell. We estimate the costs of emissions reductions from alternative fuel vehicles over the life cycle and examine the sensitivity of the results to changes in fuel prices, passenger demand, and to technological characteristics influencing performance and emissions. We find that the alternative fuel buses reduce operating costs and emissions, but increase life-cycle costs. The infrastructure requirement to deploy and operate alternative fuel buses is critical in the comparison of life-cycle emissions. Additionally, efficient bus choice is sensitive to passenger demand, but only moderately sensitive to technological characteristics, and that the relative efficiency of compressed natural gas buses is more sensitive to changes in fuel prices than that of the other bus types.     

电动自行车用氢燃料电池动力系统研究

论文研究开发了一种电电互混的电动自行车用氢燃料电池动力系统,旨在通过将燃料电池与一种具备瞬间大电流放电能力的储能设备连接,使得电动自行车用氢燃料电池动力系统在具备长航时、快速充装特性的同时,具备良好的爬坡与加速性能。文章提供了该电动自行车用氢燃料电池动力控制方法、电动自行车用氢燃料电池动力控制装置及包括该电动自行车用氢燃料电池动力控制装置的电动自行车用氢燃料电池动力系统,解决相关技术中存在的燃料电池的动态响应能力弱过载能力差的问题。     

Combining pickups and deliveries in vehicle routing – An assessment of carbon emission effects

This paper studies the effect on carbon emissions of consolidation of shipments on trucks. New positioning and communication technologies, as well as decision support systems for vehicle routing, enable better utilization of vehicle capacity, reduced travel distance, and thereby carbon emission reductions. We present a novel carbon emission analysis method that determines the emission savings obtained by an individual transport provider, who receives customer orders for outbound deliveries as well as pickup orders from supply locations. The transport provider can improve vehicle utilization by performing pickups and deliveries jointly instead of using separate trucks. In our model we assume that the transport provider minimizes costs by use of a tool that calculates detailed vehicle routing plans, i.e., an assignment of each transport order to a specific vehicle in the fleet, and the sequence of customer visit for each vehicle. We compare a basic set-up, in which pickups and deliveries are segregated and performed with separate vehicles, with two consolidation set-ups where pickups and deliveries may be mixed more or less freely on a single vehicle. By allowing mixing, the average vehicle load will increase and the total driven distance will decrease. To compare carbon emissions for the three set-ups, we use a carbon assessment method that uses the distance driven and the average load factor. An increase in the load factor can reduce part of the emission savings from consolidation. We find that emission savings are relatively large in case of small vehicles and for delivery and pickup locations that are relatively far from the depot. However, if a truck visits many demand and supply locations before returning to the depot, we observe negligible carbon emission decreases or even emission increases for consolidation set-ups, meaning that in such cases investing in consolidation through joint pickups and deliveries may not be effective. The results of our study will be useful for transport users and providers, policymakers, as well as vehicle routing technology vendors.     

Comparing carbon dioxide emissions of trucking and intermodal container transport in Taiwan

This paper examines carbon dioxide emissions of truck-only transportation using activity-based emission modelling and compares those with intermodal coastal shipping and truck movements. The results reveal that replacing long-haul truck transport with the intermodal can significantly reduce carbon dioxide emission significantly because of the efficiency of maritime fuel.