Publications

An Experimental and Modeling Study of the Flammability of Fuel Tank Headspace Vapors from High Ethanol Content Fuels

10/1/2008

An experimental and modeling study was done to determine the flammability of fuel tank headspace vapors as a function of ambient temperature for seven E85 (85% ethanol, 15% gasoline) fuel blends, two types of gasoline, and denatured ethanol at a low tank fill level. Samples in small, closed chambers were tested simultaneously in a cold chamber to determine flammability and pressure rise when ignited by a strong electric spark. Gasoline and E85 fuels were flammable below a critical temperature; above it, the vapor was too rich to burn. Denatured ethanol was flammable at room temperature and colder, down to a critical temperature; below it, the vapor was too lean to burn. The flammability limit temperature of the E85 and gasoline fuels related to the dry vapor pressure equivalent (DVPE), but DVPE did not reliably rank the low-temperature flammability hazards of fuel tank headspace vapors when conventional gasolines were compared with alcohol blends.

Authors: Gardiner, D.; Bardon, M.; Pucher, G.

National Biofuels Action Plan

10/1/2008

The Biomass Research and Development Board was created by Congress in the Biomass Research and Development Act of 2000, "to coordinate programs within and among departments and agencies of the Federal Government for the purpose of promoting the use of bio-based fuels and bio-based products by (1) maximizing the benefits deriving from Federal grants and assistance; and (2) bringing coherence to Federal strategic planning." This National Biofuels Action Plan is the result of that effort at coordination among Federal departments and agencies.

National Survey of E85 and Gasoline Prices

10/1/2008

The objective of this study was to compare the retail prices of E85 (fuel containing 85% ethanol and 15% gasoline) and regular gasoline nationally and regionally over time for one year between July 2007 and June 2008. The United States was divided into six sampling regions. A sampling plan of the approximately 1,200 E85 stations that were operating nationwide at the time was devised to allow statistically significant regional and temporal comparisons of the data to be made within the limited data collection budget available. Results indicate that the price of E85 appears to closely track that of gasoline, and the gap between E85 and gasoline appears to widen somewhat as the price of gasoline increases beyond about $3 per gallon.

Authors: Bergeron, P.

Clean Cities Annual Metrics Report 2007

9/1/2008

This report summarizes the Department of Energy's Clean Cities coalition accomplishments in 2007, including petroleum displacement data, membership, funding, sales of alternative fuel blends, deployment of AFVs and HEVs, idle reduction initiatives, and fuel economy activities.

Authors: Johnson, C.; Bergeron, P.

Statistical Analysis of the Factors Influencing Consumer Use of E85

7/1/2008

In 1997, eight E85 fuel pumps were installed at separate retail fuel stations in Minnesota to sell high-blend ethanol fuel to flexible fuel vehicle (FFV) owners. These state-level E85 efforts were part of larger federal and state policies and programs designed to promote the use of alternative fuels to displace traditional gasoline and diesel fuel. By the end of 2006, there were approximately 300 E85 fuel station locations. The amount of E85 fuel being used in the state was estimated at approximately 18 million gallons annually. Evaluating the sales patterns of E85 retail outlets can provide important information about consumer behavior regarding the use of E85, future E85 fueling infrastructure, and developing future alternative fuel policies and programs.

Authors: Bromiley, P.; Gerlach, T.; Marczak, K.; Taylor, M.; Dobrovolny, L.

St. Louis Metro Biodiesel (B20) Transit Bus Evaluation, 12-Month Final Report

7/1/2008

The St. Louis Metro Biodiesel Transit Bus Evaluation project is being conducted to evaluate the extended in-use performance of buses operating on B20 fuel. The objective of this research project is to compare B20 and ultra-low sulfur diesel buses in terms of fuel economy, vehicle maintenance, engine performance, component wear, and lube oil performance.

Authors: Barnitt, R.; McCormick, R.; Lammert, M.

Clean Cities Alternative Fuel Price Report, July 2008

7/1/2008

The Clean Cities Alternative Fuel Price Report for July 2008 is a quarterly report on the prices of alternative fuels in the U.S. and their relation to gasoline and diesel prices. This issue describes prices that were gathered from Clean Cities coordinators and stakeholders between July 21 and July 31, 2008, and then averaged in order to determine regional price trends by fuel and variability in fuel price within regions and among regions. The prices collected for this report represent retail, at-the-pump sales prices for each fuel, including Federal and state motor fuel taxes.

Table 1 reports that the nationwide average price for regular gasoline has risen 48 cents from $2.99 per gallon to $3.91 per gallon; CNG has risen 30 cents from $2.04 to $2.34; and ethanol (E85) has risen 40 cents from $2.87 to $3.27 per gallon.

Authors: Laughlin, M.D.

SunLine Begins Extended Testing of Hybrid Fuel Cell Bus

6/1/2008

After 15 years of CNG-fueled transit buses, SunLine Transit Agency in Palm Springs, California, is seeking to expand its commitment to environmentally friendly alternative power systems by testing a prototype hybrid fuel cell bus.

SunLine Transit Agency Hydrogen-Powered Transit Buses: Third Evaluation Report

6/1/2008

This report describes evaluation of operations at SunLine Transit Agency for a prototype fuel cell bus; a prototype hydrogen hybrid internal combustion engine bus; and five new compressed natural gas buses. This is the third evaluation report for SunLine Transit Agency in Thousand Palms, California. This report provides an update to the previous reports (Feb 2007 & Sep 2007) and includes results and experience through March 2008. During the data collection period (Jan 2006 - Mar 2008), SunLine operated the fuel cell bus nearly 51,000 miles in service with an overall fuel economy of 7.19 miles per kg. For comparison, SunLine's CNG buses have an average fuel economy of 3.02 miles per gasoline gallon equivalent. During the same timeframe, the HHICE bus accumulated more than 43,000 miles with an average fuel economy of 4.34 miles per kg.

Authors: Chandler, K.; Eudy, L.

Long Beach Transit: Two-Year Evaluation of Gasoline-Electric Hybrid Transit Buses

6/1/2008

This report is part of a series of evaluations from the U.S. Department of Energy (DOE). DOE, through the National Renewable Energy Laboratory (NREL), has been tracking and evaluating new propulsion systems in transit buses and trucks for more than 10 years using an established and documented evaluation protocol. This report is part of a series of evaluations from the U.S. Department of Energy (DOE). DOE, through the National Renewable Energy Laboratory (NREL), has been tracking and evaluating new propulsion systems in transit buses and trucks for more than 10 years using an established and documented evaluation protocol.

Authors: Lammert, M.

Impact of Battery Characteristics on PHEV Fuel Economy

5/12/2008

The most significant technical barrier to developing commercially viable plug-in hybrid electric vehicles (PHEVs) is the energy storage system. The challenge is to develop batteries that are able to meet both the requirements imposed by a PHEV system and market expectations of the system's cost and length of life. In this context, a vehicle systems approach is needed to investigate the operational requirements specific to PHEV technology. This paper describes work in which several tools were used to evaluate the impacts of various parameters on PHEV fuel economy. First, the impacts of the battery's energy and power were evaluated by using a global optimization algorithm. Then the impact of temperature was assessed by using two complementary approaches to evaluate battery hardware: simulation in an emulated vehicle system and actual vehicle testing.

Authors: Rousseau, A.; Shidore, N.; Carlson, Richard; Karbowski, D.

Options for Alternative Fuels and Advanced Vehicles in Greensburg, Kansas

5/1/2008

After a devastating tornado that destroyed the town of Greensburg, Kansas in May 2007, plans were developed to rebuild the town as a sustainable community. This report focuses on outlining key success factors of infrastructure, alternative vehicles, and alternative and renewable fuels as part of an integrated energy strategy.

Authors: Harrow, G.

Fuel Ethanol: Background and Public Policy Issues

4/24/2008

This report provides background concerning various aspects of fuel ethanol and a discussion of the current related policy issues. Topics include ethanol and the agricultural economy; ethanol refining and production; fuel consumption; research and development in cellulosic feedstocks; costs and benefits of fuel ethanol; and policy concerns and congressional activity.

Authors: Yacobucci, B.

Clean Cities Alternative Fuel Price Report, April 2008

4/1/2008

The Clean Cities Alternative Fuel Price Report for April 2008 is a quarterly report on the prices of alternative fuels in the U.S. and their relation to gasoline and diesel prices. This issue describes prices that were gathered from Clean Cities coordinators and stakeholders between April 1 and April 11, 2008, and then averaged in order to determine regional price trends by fuel and variability in fuel price within regions and among regions. The prices collected for this report represent retail, at-the-pump sales prices for each fuel, including Federal and state motor fuel taxes.

Table 1 reports that the nationwide average price for regular gasoline has risen 44 cents from $2.99 per gallon to $3.43 per gallon; CNG has risen 11 cents from $1.93 to $2.04; and ethanol (E85) has risen 36 cents from $2.51 to $2.87 per gallon.

Authors: Laughlin, M.D.

Analysis of the Efficiency of the U.S. Ethanol Industry 2007

3/27/2008

In 2007, the Renewable Fuels Association (RFA) conducted a survey of US ethanol production plants to provide an assessment of the current US ethanol industry. The survey covers plant operations in both corn dry mills and wet mills. In particular, it includes plant type, ownership structure, capacity, feedstocks, production volumes, coproducts,process fuel and electricity usage, water consumption, and products transportation and distribution. The survey response was based on year 2006 data. At the request of RFA, Argonne National Laboratory (ANL) has performed a statistical analysis of the survey data, as an in-kind effort, under a non-disclosure agreement (NDA) between ANL and RFA. During November 2007 and January 2008, ANL processed and analyzed the raw data for statistics. This extended technical memo serves as an official documentation to summarize ANL?s analysis.

Authors: Wu, May