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Abstract: High rates of oil consumption and obesity in the US have become important socioeconomic concerns. While these concerns may seem unrelated at first, growing obesity rates in the US increase fuel consumption by adding passenger weight to vehicles. This paper estimates the additional amount of fuel (i.e., gasoline) consumed annually by noncommercial passenger highway vehicles in the US due to passenger overweight and obesity. The mathematical model presented in this paper estimates that as many as one billion additional gallons of gasoline are consumed each year due to overweight and obesity in the US, accounting for up to 0.8% of the fuel consumed by these vehicles annually. This additional fuel consumption causes carbon dioxide emissions of up to 20 billion pounds or more, accounting for up to 0.5% of the annual carbon dioxide emissions in the transportation sector. [Copyright &y& Elsevier]

Introduction of electric vehicles (EVs) or plug-in electric vehicles (PEVs) in the road transportation can significantly reduce the carbon emission. Hence, the demand of EVs is likely to increase in the near future. Large penetration of EVs will also ultimately result into high loads on the existing power grids. The controlled charging of EVs can have a significant impact on the power grid load, voltage, frequency, and power losses. In this paper, we have provided a comprehensive review of various energy optimization approaches used for EVs charging. Energy optimization approaches used for EVs not only enhance the battery life but also contribute in regulating the voltage and frequency. During EVs charging, various objective functions such as supporting the renewable energy sources, minimization of the peak load, energy cost, and maximization of the aggregator profit have also been studied from optimization perspectives. The controlled and an optimized EVs charging enhances the performance of EVs batteries and conserves the energy in the system by minimizing the load and power losses. The different EVs charging approaches such as centralized and distributed suited for different objective functions have also been studied and compared with respect to various optimization approaches. [ABSTRACT FROM AUTHOR]

Nowadays, optimization of ship energy efficiency attracts increasing attention in order to meet the requirement for energy conservation and emission reduction. Ship operation energy efficiency is significantly influenced by environmental factors such as wind speed and direction, water speed and depth. Owing to inherent time-variety and uncertainty associated with these various factors, it is very difficult to determine optimal sailing speeds accurately for different legs of the whole route using traditional static optimization methods, especially when the weather conditions change frequently over the length of a ship route. Therefore, in this paper, a novel dynamic optimization method adopting the model predictive control (MPC) strategy is proposed to optimize ship energy efficiency accounting for these time-varying environmental factors. Firstly, the dynamic optimization model of ship energy efficiency considering time-varying environmental factors and the nonlinear system model of ship energy efficiency are established. On this basis, the control algorithm and controller for the dynamic optimization of ship energy efficiency (DOSEE) are designed. Finally, a case study is carried out to demonstrate the validity of this optimization method. The results indicate that the optimal sailing speeds at different time steps could be determined through the dynamic optimization method. This method can improve ship energy efficiency and reduce CO 2 emissions effectively. [ABSTRACT FROM AUTHOR]

This paper analyzes the energy replacement potential for high-speed passenger vessels. Emphasis is on whether better planning of services can mitigate technical and economic barriers to zero emission transport. A novel Mixed-Integer Programming problem for battery electric vessel services that jointly minimizes operator and passenger costs subject to strategic (fleet selection and land-based infrastructure location), tactical (frequency), and operational decisions (sailing pattern) is proposed. The planning problem is utilized to estimate technology replacement potential and associated costs for two existing services/routes in Norway and based on four hypothetical demand scenarios derived from the same two services. The results showcase that constraints related to battery range and charging limit the replacement potential and make energy conservation more pertinent. Abatement cost estimates range between 3 000 and 18 000 NOK per ton CO 2 , placing them well above the social cost of carbon calculated at 2 000 NOK per ton by 2030. [ABSTRACT FROM AUTHOR]

The innovations in battery technologies facilitate worldwide bus electrification, which can conserve energy and reduce emissions. This paper studies the long-term bus electrification that simultaneously optimizes the charging infrastructure deployment and bus fleet transition. The seasonal differences associated with battery capacities, bus lines, and bus timetables are considered. The studied problem is modeled as a mixed-integer linear programming formulation, in which the detailed charging schedules are determined to give the charging location and charging time. The objective minimizes both the cost and emissions. The proposed formulation is tested on a real-world case study. The computational results indicate that replacing DPBs with BEBs can save 17.8% of total cost and decrease 39.3% of carbon dioxide emission. Compared with designing a plan for each period separately, implementing long-term bus electrification can save 13.5% of total cost and 21.7% of operational cost. Moreover, the benefits of implementing long-term bus electrification are more remarkable when the planning horizon is longer. [ABSTRACT FROM AUTHOR]

This paper estimates the benefits, in terms of fuel and time, which continuous climb operations can save during the cruise phase of the flights, assuming maximum range operations. Based on previous works, a multiphase optimal control problem is solved by means of numerical optimization and using accurate aircraft performance data from the manufacturer. Optimal conventional trajectories (subject to current air traffic management practices and constraints) are computed and compared with ideal continuous operations only subject to aircraft performance constraints. Trip fuel and time for both concepts of operations are quantified for two aircraft types (a narrow-body and a wide-body airplane) and a representative set of different trip distances and landing masses. Results show that the continuous cruise phase can lead to fuel savings ranging from 0.5% to 2% for the Airbus A320, while for an Airbus A340 the dispersion is lower and savings lie in between 1% and 2%. Interestingly, trip time is also reduced between 1% and 5%. [ABSTRACT FROM AUTHOR]

Abstract: This paper compares and assesses fuel consumption models, cost functions, and solution methods, as they all have an influence on the resulting profile and associated fuel savings of an eco-cruise control system for passenger vehicles. An eco-cruise control system uses road topographical data obtained from a high-resolution digital map to control the vehicle velocity to optimize its fuel consumption. The optimal velocity profile is the result of an optimal control problem. [Copyright &y& Elsevier]

Abstract: This paper develops an integrated model for reliable estimation of daily vehicle fuel savings and emissions using an integrated traffic emission modeling approach created by incorporating the US Environmental Protection Agency’s vehicle emission model, MOVES, and the PARAMICS microscopic traffic simulation package. A case study is conducted to validate the model using a well-calibrated road network in Greenville, South Carolina. For each transportation fuel considered, both emission and fuel consumption impacts are evaluated based on market shares. [Copyright &y& Elsevier]