The U.S. DOE High Temperature Membrane Program
9/1/2007
Membranes used in current Proton Exchange Membrane (PEM) fuel cells require thermal and water management systems to control temperature and keep the membrane humidified. These components increase the weight and volume of the fuel cell system and add complexity. Estimates of the cost of the humidification systems for current membranes range from $5 to $8 per kW, while the thermal management system is estimated to cost $3 to $4 per kW. These costs must be reduced to meet the DOE transporation fuel cell system cost target of $30 per kW for the complete powertrain.
The cost and complexity of the thermal and water management systems could be minimized if the fuel cell operated at higher temperatures (up to 120 degrees C) and at lower relative humidity. Operation at 120 degrees C would also increase the tolerance of fuel cells to CO2, which would in turn reduce the cost of hydrogen from hydrocarbon sources because extraordinary steps would not be necessary to purify the hydrogen.
Authors: Kopasz, J.; Garland, N.; Manheim, A.
Water Usage for Current and Future Ethanol Production
8/23/2007
Moving and treating water consumes energy, and producing energy nearly always consumes water: the two are tightly linked. The good news is that conservation of one results in savings of the other as well. By understanding how much water is required to produce various kinds of energy, we can move toward more water-efficient energy production. In turn, recognizing how much energy is needed for various components of our water systems will help us identify opportunities for greater efficiency. This issue's articles look at both sides.
Authors: Aden, A.
Lessons Learned from the Alternative Fuels Experience and How They Apply to the Development of a Hydrogen-Fueled Transportation System
8/1/2007
DOE's Office of Energy Efficiency and Renewable Energy sponsored a two-phased study of 1) the success/failure of alternative-fuel vehicle programs and corresponding legislative policies, and 2)how well alternative fuels and vehicles met customer requirements and achieved economic viability. This study was undertaken in order to assess the role of government policy and its stability as it affects industry and consumer behaviors; optimize strategies related to the introduction of hydrogen in the end-user sector; and avoid repeating mistakes of previous transportation technology introduction programs.
Authors: Melendez, M.; Theis, K.; Johnson, C.
Innovative Policies Boost E85 Use in Illinois
8/1/2007
Fact sheet describes the innovative policies that have increased the availability and use of E85 ethanol in Illinois. The state legislature voted to eliminate the state sales tax on E85; established a state fund to cover the costs of installing E85 infrastructure; and requires all state agencies to purchase flexible-fuel vehicles with only limited exceptions.
Clean Cities Alternative Fuel Price Report, July 2007
7/1/2007
The July 2007 Clean Cities Alternative Fuel Price Report is a quarterly report keeping you up to date on the prices of alternative fuels in the U.S. and their relation to gasoline and diesel prices. This issue discusses prices that were gathered from Clean Cities coordinators and stakeholders between July 3, 2007 and July 13, 2007, 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 illustrates that all fuel prices except propane and biodiesel have risen but the price increases are well below the increase in the price of regular gasoline. CNG is almost a dollar less than gasoline on an energy-equivalent basis.
Authors: Laughlin, M.D.
Environmental Assessment of Plug-In Hybrid Electric Vehicles, Vol. 1: Nationwide Greenhouse Gas Emissions (Executive Summary)
7/1/2007
This report describes the first detailed, nationwide analysis of greenhouse gas (GHG) impacts of plug-in hybrid electric vehicles. The "well-to-wheels" analysis accounted for emissions from the generation of electricity to charge PHEV batteries and from the production, distribution, and consumption of gasoline and diesel motor fuels. Conclusions indicate annual and cumulative GHG emissions are reduced significantly across each of the nine scenario combinations of PHEV fleet penetration; and annual GHG emissions reductions were significant in every scenario combination of the study. Cumulative GHG emissions reductions between 2010 and 2050 can range from 3.4 to 10.3 billion metric tons. Each region of the country will yield reductions in GHG emissions.
Notes: To download entire document go to: http://www.epri.com/abstracts/Pages/ProductAbstract.aspx?productId=000000000001015325 EPRI makes no warranty or representations, expressed or implied, with respect to the accuracy, completeness, or usefulness of the information contained in the material. Additionally, EPRI assumes no liability with respect to the use of, or for damages resulting from the use of the material.
Environmental Assessment of Plug-In Hybrid Electric Vehicles, Vol. 2: United States Air Quality Analysis Based on AEO-2006 Assumptions for 2030 (Executive Summary)
7/1/2007
Because of the significant reduction in emissions from gasoline and diesel fuel use and because caps are in place for some conventional pollutants for the electric power sector, this study finds that in many regions of the U.S., deployment of plug-in hybrid electric vehicles (PHEVs)would reduce exposures to ozone and particulate matter, and reduce deposition rates for acids, nutrients, and mercury. On the other hand, because of assuming no further controls beyond existing regulations for the power sector, ozone levels would increase locally in some areas. Similarly, the direct emissions of particulate matter and mercury would increase somewhat and some regions and populations would experience marginal increases in exposures to those pollutants. However, as explained in the key findings, PHEVs do not increase the U.S. contribution to the global mercury budget over the long term.
Notes: To download entire document go to: http://www.epri.com/abstracts/Pages/ProductAbstract.aspx?ProductId=000000000001015326. EPRI makes no warranty or representations, expressed or implied, with respect to the accuracy, completeness, or usefulness of the information contained in the material. Additionally, EPRI assumes no liability with respect to the use of, or for damages resulting from the use of the material.
Clean Cities Annual Metrics Report 2006
7/1/2007
Clean Cities coordinators submit an annual report of their activities and accomplishments for the previous calendar year. Coordinators submit a range of data that characterize the membership, funding, projects, and activities of their coalitions as well as data about sales of alternative fuel blends, deployment of alternative fuel vehicles, hybrid electric vehicles, idle reduction initiatives, and fuel economy activities. NREL analyzes the data and translates them into gasoline reduction impacts.
Survey results indicate that about 375 million gallons of gasoline were displaced through Clean Citiew efforts in 2006, 50 percent more than in 2005. Alternative fuel vehicles accounted for 71 percent of the reduction. Biofuels (ethanol and biodiesel) used in AFVs displaced 128 million gallons, 34 percent of the total 375 million.
Authors: Bergeron, P.; Putsche, V.
Learning Demonstration Interim Progress Report - Summer 2007
7/1/2007
This report discusses key results from DOE's Controlled Hydrogen Fleet and Infrastructure Validation and Demonstration Project. The primary goal of this project is to validate vehicle and infrastructure systems using hydrogen as a transportation fuel for light-duty vehicles. The purpose is to validate the use of fuel cell vehicles and hydrogen refuelign infrastructure under real-world conditions using multiple sites, varying climates, and a variety of sources for hydrogen.
Authors: Wipke, K.; Sprik, S.; Thomas, H.; Welch, C.; Kurtz, J.
Characterization of Fine Particle and Gaseous Emissions During School Bus Idling
6/8/2007
The particulate matter (PM) and gaseous emissions from 6 diesel school buses were determined over a simulated waiting period typical of schools in the NE United States. Testing was conducted for both continuous idel and hot restart conditions using a suite of on-line particle and gas analyzers installed in the U.S. Environmental Protection Agency's Diesel Emissions Aerosol Laboratory. Results of the study showed little difference in the measured emissions between a 10-minute post-restart idle and a 10-minute continuous idle with the exception of total hydrocarbons and formaldehyde. However, an emissions pulse was observed during engine restart. A predictive equation was developed from the experimental data, which allows a comparison between continuous idle and hot restart for NOx, CO, PM-2.5, and PAHs. This equation indicates that restart is the preferred operating scenario as long as there is no extended idling after the engine is restarted.
Authors: Kinsey, J.; Williams, D.; Dong, Y.; Logan, R.
Biofuels: DOE Lacks a Strategic Approach to Coordinate Increasing Production with Infrastructure Development and Vehicle Needs
6/1/2007
Combined ethanol and biodiesel production increased rapidly between 2004 and 2006 but composed only 3 percent of 2006 U.S. transportation fuel use. Existing biofuel distribution infrastructure has limited capacity to transport the fuels and deliver them to consumers. In 2006, an estimated 4.5 million flexible fuel vehicles capable of operating on E85 were in use--an estimated 1.8 percent of the nearly 244 million U.S. vehicles.
The Government Accounting Office (GAO) has found that the U.S. Department of Energy (DOE) has not yet developed a comprehensive approach to coordinate its strategy for expanding biofuels production with the development of biofuel infrastructure and the production of vehicles. Such an approach could assist in determining which biofuel blend would most effectively and efficiently increase the use of the fuel and what infrastructure development or vehicle production is needed to support that blend level.
Coalition Cooperation Defines Roadmap for E85 and Biodiesel
6/1/2007
The Colorado Biofuels Coalition was formed in late 2005 and has a goal to expand the number of E85 stations in Colorado from 10 to 50 by the end of 2007. This coalition is an example of cooperation between the state executive office, the state office of health and environment, state and local fleets, fuel producers and distributors, Clean Cities Coalitions, and OEMs. The organization, members, and strategies for effecting this change are detailed as well as techniques for dealing with specific issues including funding.
Costs and Emissions Associated with Plug-In Hybrid Electric Vehicle Charging in the Xcel Energy Colorado Service Territory
5/1/2007
The combination of high oil costs, concerns about oil security and availability, and air quality issues related to vehicle emissions are driving interest in ?plug-in? hybrid electric vehicles (PHEVs). PHEVs are similar to conventional hybrid electric vehicles, but feature a larger battery and plug-in charger that allows electricity from the grid to replace a portion of the petroleum-fueled drive energy. PHEVs may derive a substantial fraction of their miles from grid-derived electricity, but without the range restrictions of pure battery electric vehicles. As of early 2007, production of PHEVs is essentially limited to demonstration vehicles and prototypes. However, the technology has received considerable attention from the media, national security interests, environmental organizations, and the electric power industry. The use of PHEVs would represent a significant potential shift in the use of electricity and the operation of electric power systems. Electrification of the transportation sector could increase generation capacity and transmission and distribution (T&D) requirements, especially if vehicles are charged during periods of high demand. This study is designed to evaluate several of these PHEV-charging impacts on utility system operations within the Xcel Energy Colorado service territory.
Authors: Parks, K.; Denholm, P.; Markel, T.