Ahluwalia R.K.,Argonne National Laboratory |
Wang X.,Argonne National Laboratory |
Kwon J.,Argonne National Laboratory |
Rousseau A.,Argonne National Laboratory |
And 2 more authors.
Journal of Power Sources | Year: 2011
An automotive polymer-electrolyte fuel cell (PEFC) system with ultra-low platinum loading (0.15 mg-Pt cm-2) has been analyzed to determine the relationship between its design-point efficiency and the system efficiency at part loads, efficiency over drive cycles, stack and system costs, and heat rejection. The membrane electrode assemblies in the reference PEFC stack use nanostructured, thin-film ternary catalysts supported on organic whiskers and a modified perfluorosulfonic acid membrane. The analyses show that the stack Pt content can be reduced by 50% and the projected high-volume manufacturing cost by >45% for the stack and by 25% for the system, if the design-point system efficiency is lowered from 50% to 40%. The resulting penalties in performance are a <1% reduction in the system peak efficiency; a 2-4% decrease in the system efficiency on the urban, highway, and LA92 drive cycles; and a 6.3% decrease in the fuel economy of the modeled hybrid fuel-cell vehicle on the combined cycle used by EPA for emission and fuel economy certification. The stack heat load, however, increases by 50% at full power (80 kWe) but by only 23% at the continuous power (61.5 kWe) needed to propel the vehicle on a 6.5% grade at 55 mph. The reduced platinum and system cost advantages of further lowering the design-point efficiency from 40% to 35% are marginal. The analyses indicate that thermal management in the lower efficiency systems is very challenging and that the radiator becomes bulky if the stack temperature cannot be allowed to increase to 90-95 °C under driving conditions where heat rejection is difficult. © 2011 Elsevier B.V. All rights reserved.
James B.D.,Directed Technologies Inc. |
Kalinoski J.A.,Directed Technologies Inc. |
Podolski W.,Argonne National Laboratory |
Benjamin T.,Argonne National Laboratory |
Kopasz J.,Argonne National Laboratory
Journal of Power Sources | Year: 2011
This paper is a summary of the manufacturing processes used in recent automotive fuel cell system cost analyses funded by the U.S. Department of Energy (DOE). Through these analyses, DOE examines the projected cost of an 80-kW polymer-electrolyte fuel cell system manufactured at a rate of 500,000 systems per year. Directed Technologies Inc. (DTI) and TIAX LLC (TIAX) have been contracted independently to perform such analysis since 2006, and both have prior experience. This paper addresses the most recent fuel cell configurations envisioned by DTI and TIAX. DTI has recently presented their 2010 analysis results and TIAX has recently presented their 2009 results with preliminary 2010 results. Since these presentations do not document in full, the underlying details and assumptions, DTI and TIAX's most recent comprehensive written reports are used for the present discussion. DTI's most recent report detailed 2009 technology, and TIAX's most recent report detailed 2008 technology. The summary of manufacturing process assumptions is meant to impart a sense of the rigor of the cost analyses funded by the DOE, and to provide the reader with an overview of the manufacturing processes used for fuel cells.
Lubrecht M.D.,Directed Technologies Inc.
Environmental Science and Technology | Year: 2012
Although HDD is recognized as an effective method to achieve cleanup goals at many contaminated sites, its role as part of a sustainable remediation effort has not been deeply explored. Environmental HDD, examined from the perspective of GSR, can be an effective tool in meeting sustainability goals for remediation. When designing a remediation effort, it is worth the effort to compare the long-term economic and environmental costs of installation, operation, and maintenance between systems based on horizontal wells and other methods, in many cases, HDD may prove to be a superior choice. © 2012 American Chemical Society.
Directed Technologies Inc. | Date: 2015-11-06
A drill assembly with a drill body coupled to a drilling string and a sonde body having a least one chamber defined therein for receiving locating electronics therein. In disclosed embodiment, the one or more chambers may be provided and the electronics can include a battery, a sensor, a transmitter, an antenna and connecting wires. One or more secure windows may be provided in the sonde body to allow the locating electronics to wirelessly transmit outside of the sonde body. The electronics may be potted within the chamber with a solidifying potting agent to improve durability of the electronics in a drilling environment.