Model-Based Analysis of Electric Drive Options for Medium-Duty Parcel Delivery Vehicles


Book Description

Medium-duty vehicles are used in a broad array of fleet applications, including parcel delivery. These vehicles are excellent candidates for electric drive applications due to their transient-intensive duty cycles, operation in densely populated areas, and relatively high fuel consumption and emissions. The National Renewable Energy Laboratory (NREL) conducted a robust assessment of parcel delivery routes and completed a model-based techno-economic analysis of hybrid electric vehicle (HEV) and plug-in hybrid electric vehicle configurations. First, NREL characterized parcel delivery vehicle usage patterns, most notably daily distance driven and drive cycle intensity. Second, drive-cycle analysis results framed the selection of drive cycles used to test a parcel delivery HEV on a chassis dynamometer. Next, measured fuel consumption results were used to validate simulated fuel consumption values derived from a dynamic model of the parcel delivery vehicle. Finally, NREL swept a matrix of 120 component size, usage, and cost combinations to assess impacts on fuel consumption and vehicle cost. The results illustrated the dependency of component sizing on drive-cycle intensity and daily distance driven and may allow parcel delivery fleets to match the most appropriate electric drive vehicle to their fleet usage profile.










Advanced Electric Drive Vehicles


Book Description

Electrification is an evolving paradigm shift in the transportation industry toward more efficient, higher performance, safer, smarter, and more reliable vehicles. There is in fact a clear trend to move from internal combustion engines (ICEs) to more integrated electrified powertrains. Providing a detailed overview of this growing area, Advanced Electric Drive Vehicles begins with an introduction to the automotive industry, an explanation of the need for electrification, and a presentation of the fundamentals of conventional vehicles and ICEs. It then proceeds to address the major components of electrified vehicles—i.e., power electronic converters, electric machines, electric motor controllers, and energy storage systems. This comprehensive work: Covers more electric vehicles (MEVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), range-extended electric vehicles (REEVs), and all-electric vehicles (EVs) including battery electric vehicles (BEVs) and fuel cell vehicles (FCVs) Describes the electrification technologies applied to nonpropulsion loads, such as power steering and air-conditioning systems Discusses hybrid battery/ultra-capacitor energy storage systems, as well as 48-V electrification and belt-driven starter generator systems Considers vehicle-to-grid (V2G) interface and electrical infrastructure issues, energy management, and optimization in advanced electric drive vehicles Contains numerous illustrations, practical examples, case studies, and challenging questions and problems throughout to ensure a solid understanding of key concepts and applications Advanced Electric Drive Vehicles makes an ideal textbook for senior-level undergraduate or graduate engineering courses and a user-friendly reference for researchers, engineers, managers, and other professionals interested in transportation electrification.




Field Evaluation of Medium-Duty Plug-in Electric Delivery Trucks


Book Description

This report focuses on medium-duty electric delivery vehicles operated by Frito-Lay North America (FLNA) at its Federal Way, Washington, distribution center. The 100% electric drive system is an alternative to conventional diesel delivery trucks and reduces both energy consumption and carbon dioxide (CO2) emissions. The vehicles' drive cycles and operation are analyzed and compared to demonstrate the importance of matching specific electric vehicle (EV) technologies to the appropriate operational duty cycle. The results of this analysis show that the Smith Newton EVs demonstrated a 68% reduction in energy consumption over the data reporting period compared to the conventional diesel vehicles, as well as a 46.4% reduction in CO2 equivalent emissions based on the local energy generation source. In addition to characterizing the in-use performance of the EVs compared to the conventional diesels, detailed facility load data were collected at the main building power feed as well as from each of the 10 EV chargers to better understand the broader implications associated with commercial EV deployment. These facility loads were incorporated into several modeling scenarios to demonstrate the potential benefits of integrating onsite renewables.




The Evaluation of the Impact of New Technologies for Medium-Duty Parcel Delivery Trucks on Fuel Consumption


Book Description

In this paper, researchers at the National Renewable Energy Laboratory present the results of simulation studies to evaluate potential fuel savings as a result of improvements to vehicle rolling resistance, coefficient of drag, and vehicle weight as well as hybridization for four power trains for medium-duty parcel delivery vehicles. The vehicles will be modeled and simulated over 1,290 real-world driving trips to determine the fuel savings potential based on improvements to each technology and to identify best use cases for each platform. The results of impacts of new technologies on fuel saving will be presented, and the most favorable driving routes on which to adopt them will be explored.




Hydraulic Hybrid and Conventional Parcel Delivery Vehicles' Measured Laboratory Fuel Economy on Targeted Drive Cycles


Book Description

This research project compares laboratory-measured fuel economy of a medium-duty diesel powered hydraulic hybrid vehicle drivetrain to both a conventional diesel drivetrain and a conventional gasoline drivetrain in a typical commercial parcel delivery application. Vehicles in this study included a model year 2012 Freightliner P100H hybrid compared to a 2012 conventional gasoline P100 and a 2012conventional diesel parcel delivery van of similar specifications. Drive cycle analysis of 484 days of hybrid parcel delivery van commercial operation from multiple vehicles was used to select three standard laboratory drive cycles as well as to create a custom representative cycle. These four cycles encompass and bracket the range of real world in-use data observed in Baltimore United ParcelService operations. The NY Composite cycle, the City Suburban Heavy Vehicle Cycle cycle, and the California Air Resources Board Heavy Heavy-Duty Diesel Truck (HHDDT) cycle as well as a custom Baltimore parcel delivery cycle were tested at the National Renewable Energy Laboratory's Renewable Fuels and Lubricants Laboratory. Fuel consumption was measured and analyzed for all three vehicles.Vehicle laboratory results are compared on the basis of fuel economy. The hydraulic hybrid parcel delivery van demonstrated 19%-52% better fuel economy than the conventional diesel parcel delivery van and 30%-56% better fuel economy than the conventional gasoline parcel delivery van on cycles other than the highway-oriented HHDDT cycle.




Medium-Duty Plug-in Electric Delivery Truck Fleet Evaluation


Book Description

In this paper, the authors present an overview of medium-duty electric vehicle (EV) operating behavior based on in-use data collected from Smith Newton electric delivery vehicles and compare their performance and operation to conventional diesel trucks operating in the same fleet. The vehicles' drive cycles and operation are analyzed and compared to demonstrate the importance of matching specific EV technologies to the appropriate operational duty cycle. The results of this analysis show that the Smith Newton EVs demonstrated a 68% reduction in energy consumption over the data reporting period compared to the conventional diesel vehicles, as well as a 46.4% reduction in carbon dioxide equivalent emissions based on the local energy generation source.




NREL/Industry Range-Extended Electric Vehicle for Package Delivery


Book Description

Range-extended electric vehicle (EV) technology can be a viable option for reducing fuel consumption from medium-duty (MD) and heavy-duty (HD) engines by approximately 50 percent or more. Such engines have wide variations in use and duty cycles, however, and identifying the vocations/duty cycles most suitable for range-extended applications is vital for maximizing the potential benefits. This presentation provides information about NREL's research on range-extended EV technologies, with a focus on NREL's real-world data collection and analysis approach to identifying the vocations/duty cycles best suited for range-extender applications and to help guide related powertrain optimization and design requirements. The presentation also details NREL's drive cycle development process as it pertains to package delivery applications.




Assessing the Battery Cost at Which Plug-In Hybrid Medium-Duty Parcel Delivery Vehicles Become Cost-Effective


Book Description

The National Renewable Energy Laboratory (NREL) validated diesel-conventional and diesel-hybrid medium-duty parcel delivery vehicle models to evaluate petroleum reductions and cost implications of hybrid and plug-in hybrid diesel variants. The hybrid and plug-in hybrid variants are run on a field data-derived design matrix to analyze the effect of drive cycle, distance, engine downsizing, batteryreplacements, and battery energy on fuel consumption and lifetime cost. For an array of diesel fuel costs, the battery cost per kilowatt-hour at which the hybridized configuration becomes cost-effective is calculated. This builds on a previous analysis that found the fuel savings from medium duty plug-in hybrids more than offset the vehicles' incremental price under future battery and fuel costprojections, but that they seldom did so under present day cost assumptions in the absence of purchase incentives. The results also highlight the importance of understanding the application's drive cycle specific daily distance and kinetic intensity.