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.     

PM,NOx and CO2 emission reductions from speed management policies in Europe

Speed reduction measures rank among the most common schemes to improve traffic safety. Recently many urban streets or entire districts were converted into 30 kph zones and in many European countries the maximum permissible speed of trucks on motorways is under discussion. However, besides contributing to traffic safety, reducing the maximum speed is also seen as beneficial to the environment due to the associated reduced fuel consumption and lower emissions. These claims however are often unsubstantiated.To gain greater insight into the impact of speed management policies on emissions, this paper examines the impact on different traffic types (urban versus highway traffic) with different modelling approaches (microscopic versus macroscopic). Emissions were calculated for specific types of vehicles with the microscopic VeTESS-tool using real-world driving cycles and compared with the results obtained using generalized Copert-like macroscopic methodologies. We analyzed the relative change in pollutants emitted before and after the implementation of a speed reduction measure for passenger cars on local roads (50–30 kph) and trucks on motorways (90–80 kph). Results indicate that emissions of most classic pollutants for the research undertaken do not rise or fall dramatically. For the passenger cars both methods indicate only minor changes to the emissions of NO_x and CO₂. For PM, the macroscopic approach predicts a moderate increase in emissions whereas microscopic results indicate a significant decrease. The effects of specific speed reduction schemes on PM emissions from trucks are ambiguous but lower maximums speed for trucks consistently result in lower emissions of CO₂ and lower fuel consumption. These results illustrate the scientific uncertainties that policy makers face when considering the implementation of speed management policies.     

Negotiating truck arrival times among trucking companies and a container terminal

Congestion of trucks in port areas has created serious environmental and traffic problems in many countries. One of main reasons for congestion is the concentrated arrivals of road trucks at peak hours. A negotiation process for smoothing truck arrivals in peak hours among multiple trucking companies and a terminal is addressed. The negotiation process is to be used for the appointment system for road trucks in container terminals. This paper suggests a mathematical formulation for smoothing the peaks in arrivals considering the inconvenience of trucks from changing their arrival times and the waiting cost of trucks in peak hours. This study proposes a decentralized decision-making model to support the negotiation process between truck companies and the terminal operator. It gives an acceptable solution to every player involved as well as the near optimal solution to the entire system from the global point of view. Numerical experiments are performed to validate the approach in this study.     

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.     

The Trucking Sector Optimization Model: A tool for predicting carrier and shipper responses to policies aiming to reduce GHG emissions

In response to the growing Climate Change problem, governments around the world are seeking to reduce the greenhouse gas (GHG) emissions of trucking. The Trucking Sector Optimization (TSO) model is introduced as a tool for studying the decisions that shippers and carriers make throughout time (focusing on investments in Fuel Saving Technologies), and for evaluating their impact on life-cycle GHG emissions. A case study of fuel taxation in California is used to highlight the importance of (1) modeling the trucking sector comprehensively, (2) modeling the dynamics of the stock of vehicles, and (3) modeling different sources of emissions.     

Potential cost savings of frequent flyer miles for business travel

The mileage redemption strategy is a procedure used by many business firms to reduce air travel costs, in which the frequent flyer miles of traveling employees accumulated during business trips are applied to their future business trips to obtain “free” air tickets. This paper presents a framework that investigates how the frequent flyer miles can be used in the most effective way to reduce air travel costs by those firms that are either using the mileage redemption strategy or considering the use of the strategy. The framework can be implemented quite easily by a spreadsheet software such as Microsoft Excel.     

Fuel economy gaps within and across garages: A bivariate random parameters seemingly unrelated regression approach

The key objective of this study is to investigate the interrelationship between fuel economy gaps and to quantify the differential effects of several factors on fuel economy gaps of vehicles operated by the same garage. By using a unique fuel economy database (fueleconomy.gov), users’ self-reported fuel economy estimates and government’s fuel economy ratings are analyzed for more than 7000 garages across the United States. The empirical analysis, nonetheless, is complicated owing to the presence of important methodological concerns including potential interrelationship between vehicles within the same garage and unobserved heterogeneity. To address these concerns, bivariate seemingly unrelated fixed and random parameter models are presented. With government’s test cycle ratings tending to over-estimate the actual on-road fuel economy, a significant variation is observed in the fuel economy gaps for the two vehicles across garages. A wide variety of factors such as driving style, fuel economy calculation method, and several vehicle-specific characteristics are considered. Drivers who drive for maximum gas mileage or drives with the traffic flow have greater on-road fuel economy relative to the government’s ratings. Contrarily, volatile drivers have smaller on-road fuel economy relative to the official ratings. Compared to the previous findings, our analysis suggests that the relationship between fuel type and fuel economy gaps is complex and not unidirectional. Regarding several vehicle and manufacturer related variables, the effects do not just significantly vary in magnitude but also in the direction, underscoring the importance of accounting for within-garage correlation and unobserved heterogeneity for making reliable inferences.     

Reducing truck emissions at container terminals in a low carbon economy: Proposal of a queueing-based bi-objective model for optimizing truck arrival pattern

This study proposes a methodology to optimize truck arrival patterns to reduce emissions from idling truck engines at marine container terminals. A bi-objective model is developed minimizing both truck waiting times and truck arrival pattern change. The truck waiting time is estimated via a queueing network. Based on the waiting time, truck idling emissions are estimated. The proposed methodology is evaluated with a case study, where truck arrival rates vary over time. We propose a Genetic Algorithm based heuristic to solve the resulting problem. Result shows that, a small shift of truck arrivals can significantly reduce truck emissions, especially at the gate.     

Truck movement across the Canada–US border: The effects of 9/11 and other factors

The objective of this study is to isolate the effects of the terrorist attacks of 9/11 and the subsequent stringent border security regime on the levels of truck movement across the Canada–US border. A time series analysis, within an econometric system that rendered stationarity and used the seemingly unrelated regression (SUR) estimator, was performed to model these movements. The analysis represents a natural experiment on the variability of cross-border truck movements in the aftermath of 9/11. Annual truck crossing data over the period 1972–2011, disaggregated by the country of registration (US and Canada) and Canadian jurisdictions (provinces) were used in the analysis. The results indicate that in general, 9/11 have had a negative effect on the cross-border movement of Canadian and US trucks, but the impacts were more pronounced in the case of the US trucks. Other interesting results include an increase in the number of US trucks during the period that followed the last US financial crisis. The results also illustrate the importance of GDP in explaining the observed truck movements across the Canada–US border.     

Exploring the relationship between truck load capacity and traffic accidents in the European Union

Applying econometric techniques to EU28 panel data and controlling for explanatory variables such as road types, we find that increased truck load capacity does not necessarily aggravate road traffic safety. Specifically, heavy trucks do not seem to be linked with greater numbers of traffic fatalities/accidents, medium trucks appear to be the worst performers in terms of fatalities, and light trucks seem to be the worst for accidents. In summary, our results clarify the complex relationship between truck load capacity and road safety, pointing to the existence of a negative correlation for accidents per capita and an inverse U-shaped curve for fatalities per capita.     

Automobile use,fuel economy and CO2 emissions in industrialized countries: Encouraging trends through 2008?

Car use and fuel economy are factors that determine oil demand and carbon dioxide (CO₂) emissions. Recent data on automobile utilization and fuel economy reveal surprising trends that point to changes in oil demand and CO₂ emissions. New vehicle and on-road fleet fuel economy have risen in Europe and Japan since the mid 1990s, and in the US since 2003. Combined with a plateau in per capita vehicle use in all countries analyzed, these trends indicate that per capita fuel use and resultant tail-pipe CO₂ emissions have stagnated or even declined.Fuel economy technology, while important, is not the only factor that explains changes in tested and on-road fuel economy, vehicle efficiency and transport emissions across countries. Vehicle size and performance choices by car producers and buyers, and driving distances have also played significant roles in total fuel consumption, and explain most of the differences among countries. Technology applied to new vehicles managed to drive down the fuel use per unit of horsepower or weight by 50%, yet most of the potential fuel savings were negated by overall increased power and weight, particularly in the US. Similarly, the promise of savings from dieselization of the fleet has revealed itself as a minor element of the overall improvement in new vehicle or on-road fuel economy. And the fact that diesels are driven so much more than gasoline cars, a difference that has increased since 1990, argues that those savings are minimal. This latter point is a reminder that car use, not just efficiency or fuel choice, is an important determinant of total fuel use and CO₂ emissions.We speculate that if the upward spiral of car weight and power slows or even reverses (as has been observed in Europe and Japan) and the now mandatory standards in many countries have the intended effect that fuel use will remain flat or only grow weakly for some time. If real fuel prices of 2008, which rivaled their peaks of the early 1980s, fell back somewhat but still remain well above their early 2000 values. If the prices remain high, this, combined with the strengthened fuel economy standards, may finally lead to new patterns of car ownership, use and fuel economy. However, if fuel prices continue their own stagnation or even decline after the peaks of 2008 and car use starts upward, fuel use will increase again, albeit more slowly.     

Potential performance of urban land use and transport strategies in reducing greenhouse gas emissions: Khon Kaen case study,Thailand

ABSTRACT

Transport activities are a key contributor to greenhouse gas (GHG) emissions, global warming, and climate change. In Thailand, private cars are the second largest generator (after trucks) of GHG emissions from the transport sector. This article presents an analysis and evaluation of the implementation of land use and transport measures for reducing GHG emissions in the road network of the Khon Kaen University (KKU) area in Khon Kaen, Thailand. This research applied a bottom-up method to estimate the baseline GHG emissions for several scenarios by adopting the Clean Development Mechanism 2 (CDM2) and Pollution Control Department (PCD) methods over a 20-year planning horizon. The cleaner technology strategy clearly showed the greatest performance in reducing the GHG emission, followed by land use planning and restriction of private vehicle usage. The public transit improvement strategy illustrated the least GHG emissions reduction. Integrated scenarios clearly illustrated larger potential benefits, more effective than the individual scenarios. For both individual and integrated scenarios, the potential performances of the GHG emissions reduction estimated by the PCD method were greater than those assessed by the CDM2 method.     

The determinants of truck accidents

This paper examines the determinants of truck accidents in the United States using a time series data set covering the period 1970–2001. Along with other factors, the effect of the Motor Carrier Act of 1980, which deregulated the trucking industry, is examined for its impact on truck accidents. In addition, the model accounts for the effect railroad freight mileage has on truck accidents. Empirically, alcohol consumption, the unemployment rate, and railroad activity were found to have significant effects on truck accidents while deregulation of the trucking industry did not have a statistically significant adverse effect on these accidents.     

Cost savings of using a marketable permit system for regulating light-duty vehicle emissions

In the USA, each individual vehicle is required to meet uniform per-mile emission standards. The uniform standard system does not allow vehicle manufacturers flexibility in achieving overall emission reduction goals for motor vehicles. The system provides manufacturers with little or no incentive to control vehicle emissions beyond what is required. In this paper, an incentive-based marketable permit system is proposed to replace the uniform standard system. Under the marketable permit system, vehicle manufacturers are required to meet corporate average emission standards; they are allowed to buy or sell vehicle emission reduction credits among themselves to meet corporate average standards; and they are allowed to bank vehicle emission reduction credits that are accumulated in earlier years and to use the credits for meeting average standards in later years. It is estimated in this study that relative to the current uniform standard system, the marketable permit system can reduce vehicle emission control costs by $150 to $400 million per year in California, or 13–30% of the costs currently spent on vehicle emission control.     

The potential for European aviation CO2 emissions reduction through the use of larger jet aircraft

There is increasing pressure to reduce global CO₂ emissions, with aviation targeted as an industry with high future expected growth and limited potential for reduced emissions. In Europe, air transport is likely to be included in the Emissions Trading Scheme from 2012, allowing open trading with other sectors. The proposed scheme may be economically efficient but will it do much towards curbing aviation emissions? A number of papers have looked at the ETS impact on air traffic growth rates, and others have forecast the rate of likely future fuel efficiency gains. This paper examines the potential for greater fuel efficiency through the use of larger aircraft and different patterns of operation. Fuel efficiency was found to be related to aircraft size with more benefit from trading up with short/medium-haul than with long-haul aircraft. This relationship only held for long-haul aircraft if those aircraft with two main decks were removed from the sample (these types showing inherently lower fuel efficiency). Combining these findings with manufacturers' and other forecasts of average aircraft size suggests that less than 1% a year of fuel efficiency gains will be available from this source over the next 20 years.     

Berth allocation considering fuel consumption and vessel emissions

We propose a more elaborate model on berth allocation considering fuel consumption than before, and overcome the nonlinear complexity by casting it as a mixed integer second order cone programming model. Furthermore, we conduct the vessel emission (in sailing periods) calculation with the widely-used emission factors. Besides, vessel emissions in mooring periods are also analyzed through a post-optimization phase on waiting time. Experimental results demonstrate that the new berth allocation strategy, reflected by the proposed model, is competent to significantly reduce fuel consumption and vessel emissions, while simultaneously retaining the service level of the terminal.     

Strategic travel planning toward future emission targets—A comparative analysis of 20 Swedish municipalities applying the CERO model

Organizations displaying best practices for attaining proactive sustainability targets at local level are of major importance as role models in the transition toward a sustainable transport system. This study summarizes results and conclusions from 20 municipalities in Sweden that have implemented the so called CERO analysis in order to adapt to future emission targets for travel. The overall aim of the study is to identify factors explaining why some municipalities are more successful than others in a benchmarking comparison.

The results indicate that commuting by car is by far the most dominant source of emissions, constituting on average 76% of total annual travel emissions (including both commuting and business travel). In order to reduce these emissions, travel planning programs within organizations must address both commuting conditions and business travel conditions to reduce car dependence for work travel, e.g., employees using private cars for business trips most likely also use their own cars for commuting. To identify potential success factors as regards emissions-efficient travel, three comparative statistical analyses were conducted: grouping municipalities with low emissions in relation to the total average; analysis of car commuters' willingness to change travel mode; and before-and-after analyses of municipalities implementing specific action plans. The results revealed that municipalities conducting follow-up studies 2 years after implementing travel planning programs all lowered their total CO₂ emissions, by on average 10% during a 2-year period. Overall, these municipalities achieved redistribution to alternative travel modes but also reduced total travel mileage.     

An analysis of per mile pollution fees for motor vehicles in California''s south coast

This paper examines the effect of pollution fees based on per mile emissions of reactive organic gases and oxides of nitrogen on tons of pollutants emitted, driving, fuel use and efficiency, new vehicle sales, and welfare in the South Coast region of California. The results suggest that VMT and gasoline demand would be reduced (although at a declining rate) while mpg would improve as households shifted to newer vehicles. Sales of new vehicles are projected to initially rise, then drop below base forecast levels as turnover of vehicles is reduced. Finally, the projected effects on household consumer surplus suggest that pollution fees may be regressive (although less so as households adjust their vehicle holdings), as a significant portion of older, higher polluting vehicles are owned by lower income households. The paper also compares pollution fees with voluntary accelerated vehicle retirement programs.     

Methods of air traffic management in the airport area including the environmental factor

In the modern approach to air traffic management (ATM), issues related to air quality and climate protection have led to the introduction of a growing number of new restrictions instead of having these issues be the objectives of actions taken. The aim of the study was to investigate whether it is possible to improve air quality while controlling pollution emission by introducing changes in the organization of air traffic control at the airport. For this purpose, mathematical models of emissions were created. These concern the movement of aircraft near the airport and emission of carbon dioxide and the spread of human health related substances emitted from a landing airplane's engine. The first case refers to the possibility of using different arrival procedures. The second case was to adapt the Pasquill formula by treating landing aircraft as a sequence of point-source emissions. As a result of applying the designed models and software tools, it was proven that both a change in the arrival trajectory and a change of the runway can contribute to a reduction of CO₂ emission into the atmosphere. The emission maps created for different aircraft approach profiles show the ability to control the local concentration of harmful emissions. The study clearly shows that the current approach of maximizing throughput is not beneficial to air quality. ATM services should consider the use of other variants of air traffic organization, particularly during periods of reduced traffic.     

Modeling fuel saving investments and fleet management in the trucking industry: The impact of shipment performance on GHG emissions

Much has been written about the potential of technologies to reduce the greenhouse gas (GHG) emissions of trucking, but much less on the determinants of these investments. The Trucking Sector Trip Segmentation Model (TSTS) predicts how firms make these investments in the context of operating heterogeneous truck fleets to service the spatially dispersed demand of shippers. This analysis suggests that improving the performance of trucking (speeding up shipments) could reduce significantly GHG emissions: investments in technologies are incentivized by fuel savings accruing sooner. This effect could be potentially large in the US as trucking firms often discount the future heavily.