Plug-In Hybrid Vehicle Analysis - Milestone Report
9/1/2006
NREL's plug-in hybrid electric vehicle (PHEV) analysis activities in FY06 were aimed at objectively assessing PHEV technology, support the larger U.S. DOE PHEV assessment effort, and share technical knowledge with the vehicle research community and vehicle manufacturers. This report includes research papers and presentations developed in FY06 and focuses on fuel economy reporting methods, cost and consumption benefit analysis, real-world performance expectations, and energy management strategies.
Authors: Markel, T.; Brooker, A.; Gonder, J.; O'Keefe, M.; Simpson, A.; Thornton, M.
Notes: To request this document on CD, contact Techical Support Resources at 800-254-6735.
King County Metro Transit: Allison Hybrid Electric Transit Bus Laboratory Testing
9/1/2006
The National Renewable Energy Laboratory's ReFUEL facility conducted chassis dynamometer testing of two 60-foot articulated transit buses, one conventional and one hybrid. Both test vehicles were 2004 New Flyer buses powered by Caterpillar C9 8.8L engines, with the hybrid vehicle incorporating a GM-Allison advanced hybrid electric drivetrain. Both vehicles also incorporated an oxidizing diesel particulate filter. The hybrid vehicle demonstrated the greatest improvement in fuel economy in the low speed, heavy stop-and-go driving conditions of the Manhattan (N.Y.)test cycle (74.6%), followed by the Orange County (Calif.) test cycle (50.6%), the Central Business District cycle (48.3%), and the King County (Wash.) Metro test cycle (30.3%). Emission trends were similar to fuel economy improvement trends. The hybrid shoed reductions in NOx emissions over the Manhattan cycle (38.7%), the Orange County cycle (28.6%), the Central Business District cycle (26.6%), and the King County test cycle (17.8%). Vehicle exhaust emissions, fuel consumption, and state of charge of the energy storage system were measured for repeated test conditions. The remainder of this document includes the experimental setup, test procedures, and results from vehicle testing performed at the NREL ReFUEL laboratory.
Authors: Hayes, R.R.; Williams, A.; Ireland, J.; Walkowicz, K.
Case Study: Ebus Hybrid Electric Buses and Trolleys
7/1/2006
The Indianapolis Transportation Corp. and Knoxville Area Transit participated in a demonstration of hybrid electric buses and trolleys produced by Ebus, Inc. of Downey, California. This is a case study of performance, costs, and maintenance experience.
Authors: Barnitt, R.
SunLine Expands Horizons with Fuel Cell Bus Demo
5/1/2006
Sunline Transit Agency, a joint powers authority that provides public transit and community services to California's Coachella Valley, was an early adopter of alternative fuels for bus operations. SunLine replaced its diesel fleet with CNG buses and has worked to further reduce emissions. SunLine is currently testing a prototype fuel cell bus.
Hybrid Electric Vehicle Fleet and Baseline Performance Testing
4/3/2006
The U.S. Department of Energy's Advanced Vehicle Testing Activity (AVTA) conducts baseline performance and fleet testing of hybrid electric vehicles (HEV). To date, the AVTA has completed baseline performance testing on 7 HEV models and accumulated 1.4 million fleet testing miles on 26 HEVs. Tested models include: Toyota Gen I and Gen II Prius, and Highlander; Honda Insight, Civic and Accord; Chevrolet Silverado; Ford Escape; and Lexus RX 400h. The baseline performance testing includes dynamometer and closed track testing to document the HEV's fuel economy and performance in a controlled environment. During fleet testing, two of each HEV model were driven to 160,000 miles per vehicle. At the conclusion of the 160,000 miles of fleet testing, fuel economy tests were rerun and each HEV battery pack was tested. The paper discusses the testing methods and results.
Authors: Francfort, J.; Karner, D.; Harkins, R.; Tardiolo, J.
Notes: Paper is available for purchase from SAE.
A Preliminary Assessment of Plug-In Hybrid Electric Vehicles on Wind Energy Markets
4/1/2006
This report presents a very preliminary analysis of plug-in hybrid electric vehicles (PHEVs) that can be charged from or discharged to the electric grid. These vehicles have the potential to reduce gasoline consumption and carbon emissions from vehicles, as well as improve the viability of renewable energy technologies with variable resource availability. This paper is an assessment of the synergisms between plug-in hybrid electric vehicles and wind engery used to generate the necessary electricity.
Authors: Short, W.; Denholm, P.
King County Metro Transit Hybrid Articulated Buses: Interim Evaluation Results
4/1/2006
This is an interim technical report comparing and evaluating new diesel and diesel hybrid-electric articulated buses operated as part of the King County Metro Transit fleet in Seattle, Washington. This report covers the first six months of a planned 12-month evaluation.
Authors: Chandler, K., Walkowicz, K.
Lessons Learned from Alternative Transportation Fuels: Modeling Transition Dynamics
2/1/2006
Much attention has been given to the use of hydrogen as an alternative transportation fuel, but hydrogen was certainly not the first fuel considered as an alternative to gasoline for transportation applications. Options ranging from all-electric vehicles to those running on natural gas, propane, ethanol, and biodiesel have also received both industry and government attention. Unfortunately, previous government efforts to encourage widespread adoption of alternative fuel vehicles have been largely unsuccessful. The National Academy of Engineering suggested that 'DOE might have its greatest impact by leading the private economy toward transition strategies rather than to ultimate visions of an energy infrastructure markedly different from the one now in place.'
This report focuses on understanding how analytical system modeling coupled with actual data from previous alternative-fuel experiences could improve our understanding of the dynamic forces governing the transition to an alternative-fueled vehicle system.
Authors: Welch, Cory
New York City Transit Hybrid and CNG Transit Buses: Interim Evaluation Results
1/2/2006
This report focuses on compressed natural gas (CNG) and diesel hybrid electric bus propulsion systems in New York City Transit buses. Both of these propulsion systems are alternatives to standard diesel buses and allow for reductions in petroleum use and emissions (usually focused on reductions of particulate matter and oxides of nitrogen). CNG propulsion is an alternative to diesel fuel use, and diesel hybrid propulsion allows for increased fuel economy, which, in turn, is a reduction in petroleum use.
Authors: Chandler, K.;Eberts, E.;Eudy, L.
Demonstration and Evaluation of Hybrid Diesel-Electric Transit Buses
10/25/2005
This report, written by the Connecticut Academy of Science and Engineering for the Connecticut Department of Transportation and CTTransit, details the demonstration and evaluation of hybrid diesel-electric transit buses. The project goal was to identify the next generation of transit vehicles for future fleet replacement that are cost effective, reliable, produce fewer emissions, and have improved fuel economy compared to the standard heavy-duty diesel powered bus. Data was collected to produce an estimated life-cycle cost analysis, emissions information, mileage, fuel economy, power production, brake pad wear, and maintenance and repair costs. Bus operator and customer surveys were also conducted. Results were completed on Dec. 31, 2004. The results found the hybrid buses to be very reliable and to achieve 10% better fuel economy than their comparable diesel buses. All vehicle emissions in the study were the same. The hybrid buses had a lower life-cycle cost when the current FTA 80% purchase subsidy was considered.