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The U.S. Department of Energy's Office of Energy Efficiency & Renewable Energy initiated a study that conducted coastdown testing and chassis dynamometer testing of three vehicles, each at multiple test weights, in an effort to determine the impact of a vehicle's mass on road load force and energy consumption. The testing and analysis also investigated the sensitivity of the vehicle's powertrain architecture (i.e., conventional internal combustion powertrain, hybrid electric, or all-electric) on the magnitude of the impact of vehicle mass. The three vehicles used in testing are a 2012 Ford Fusion V6, a 2012 Ford Fusion Hybrid, and a 2011 Nissan Leaf. Testing included coastdown testing on a test track to determine the drag forces and road load at each test weight for each vehicle. Many quality measures were used to ensure only mass variations impact the road load measurements.

Initial efforts in the development of an EVA portable contamination detector (EVA PCD) for use by the EVA crew have resulted in the selection and preliminary testing of a concept based upon time-of-flight(TOF) mass spectrometry. The EVA PCD will be a compact, man-portable device intended for use in the ambient vacuum outside the Space Station. It will be used to monitor the surfaces of the EVA suits and mobility units for the presence of potentially toxic contaminants, such as hydrazine propellants and oxidizers, which might otherwise be inadvertently carried into the interior of the Station. The EVA PCD will also be used to locate small leaks of heat exchange fluids in the outer surface of the Station. This paper describes some key performance needs for the EVA PCD system, approaches taken to interpreting those needs, and some of the results of tradeoff analyses which led to the selection of the TOF concept. Some results from initial experimental tests of a TOF unit are presented.

Producing and using renewable fuels for transportation is one approach for a sustainable energy future for the United States, as well as the rest of the world. Renewable fuels may also substantially reduce contributions to global climate change. In the transportation sector, ethanol produced from biomass shows promise as a future fuel for spark-ignited engines because of its high octane quality. Ethanol, however, is not a high-quality compression-ignition fuel. Ethanol can be easily converted through a dehydration process to produce diethyl ether (DEE), which is an excellent compression-ignition fuel with higher energy density than ethanol. DEE has long been known as a cold-start aid for engines, but little is known about using DEE as a significant component in a blend or as a complete replacement for diesel fuel.

A cold-start partial oxidation (POX) system was integrated with a modern flexible fuel engine to assess its impact on cold-start performance and emissions. The POX reactor, a small combustion device operating fuel rich, converts liquid fuel into gaseous fuel species (reformate). The reformate from the reactor, when mixed with combustion air, replaces or supplements the standard fuel consumed during an engine start. This prototype integrated cold-start system has successfully reduced emissions from a cold-start on fuel grade ethanol (E95) at 5°C. The integrated POX system reduced the time-averaged hydrocarbon (HC) and carbon monoxide (CO) emissions by 80 and 40 percent, respectively. Starts on E95 reformate were achieved in less than 10 seconds at temperatures as low as -20°C.

Hydrogen fuel cell vehicles (FCVs) appear to be a promising solution for the future of clean and efficient personal transportation. Issues of how to generate the hydrogen and then store it on-board to provide satisfactory driving range must still be resolved before they can compete with conventional vehicles. Alternatively, FCVs could obtain hydrogen from on-board reforming of gasoline or other fuels such as methanol or ethanol. On-board reformers convert fuel into a hydrogen-rich fuel stream through catalytic reactions in several stages. The high temperatures associated with fuel processing present an engineering challenge to warm up the reformer quickly and efficiently in a vehicle environment. Without a special warmup phase or vehicle hybridization, the reformer and fuel cell system must provide all power to move the vehicle, including ¼ power in 30 s, and ½ power in 3 min to satisfy the Federal Test Procedure (FTP) cycle demands.

In addition to high-profile fuel cell applications such as automotive propulsion and distributed power generation, the use of fuel cells as auxiliary power units (APU) for vehicles has received considerable attention. APU applications may be an attractive market because fuel cells offer some attractive features for APU applications and the APU market offers a true mass-market opportunity that does not require some of the challenging performance and cost targets required for propulsion systems for vehicles. In this paper we discuss the technical performance requirements for PEM and SOFC APUs, as well as the current status of the technology and the implications for fuel cell system configuration and cost.

This paper summarizes the Next Generation Natural Gas Vehicle (NG-NGV) Program that is led by the U.S. Department Of Energy's (DOE's) Office of Heavy Vehicle Technologies (OHVT) through the National Renewable Energy Laboratory (NREL). The goal of this program is to develop and implement one Class 3-6 compressed natural gas (CNG) prototype vehicle and one Class 7-8 liquefied natural gas (LNG) prototype vehicle in the 2004 to 2007 timeframe. OHVT intends for these vehicles to have 0.5 g/bhp-hr or lower emissions of oxides of nitrogen (NOx) by 2004 and 0.2 g/bhp-hr or lower NOx by 2007. These vehicles will also have particulate matter (PM) emissions of 0.01 g/bhp-hr or lower by 2004. In addition to ambitious emissions goals, these vehicles will target life-cycle economics that are compatible with their conventionally fueled counterparts.

This paper summarizes the several of the studies in the Environmental Science Program being sponsored by DOE's Office of Heavy Vehicle Technologies (OHVT) through the National Renewable Energy Laboratory (NREL). The goal of the Environmental Science Program is to understand atmospheric impacts and potential health effects that may be caused by the use of petroleum-based fuels and alternative transportation fuels from mobile sources. The Program is regulatory-driven, and focuses on ozone, airborne particles, visibility and regional haze, air toxics, and health effects of air pollutants. Each project in the Program is designed to address policy-relevant objectives. Current projects in the Environmental Science Program have four areas of focus: improving technology for emissions measurements; vehicle emissions measurements; emission inventory development/improvement; ambient impacts, including health effects.

The Office of Heavy Vehicle Technologies supports research to enable high-efficiency diesel engines to meet future emissions regulations, thus clearing the way for their use in light trucks as well as continuing as the most efficient powerplant for freight-haulers. Compliance with Tier 2 emission regulations for light-duty vehicles will require effective exhaust emission controls (aftertreatment) for diesels in these applications. Diesel-powered heavy trucks face a similar situation for the 2007 regulations announced by EPA in December 2000. DOE laboratories are working with industry to improve emission control technologies in projects ranging from application of new diagnostics for elucidating key mechanisms, to development and evaluation of prototype devices. This paper provides an overview of these R&D efforts, with examples of key findings and developments.

Today's advanced-technology vehicles (ATVs) feature hybrid-electric engines, regenerative braking, advanced electric drive motors and batteries, and eventually fuel cell engines. There is considerable environmental and regulatory pressure on fleets to adopt these vehicles, resulting in high-risk purchase decisions on vehicles that do not have documented performance histories. The Department of Energy's Field Operations Program tests ATVs and disseminates the results to provide accurate and unbiased information on vehicle performance (http://ev.inel.gov/fop). Enhancing the fleet manager's knowledge base increases the likelihood that ATVs will be successfully and optimally placed into fleet missions. The ATVs are tested using one or more methods - Baseline Performance, Accelerated Reliability, and Fleet Testing. The Program and its 10 testing partners have tested over three-dozen electric and hybrid electric vehicle models, accumulating over 4 million miles of testing experience.

Cost is one of the critical factors in the commercialization of PEM fuel cells in automotive markets. Arthur D. Little has been working with the U.S. Department of Energy, Office of Transportation Technologies to assess the cost of fuel-flexible reformer proton exchange membrane (PEM) fuel cell systems based on near-term technology but cost modeled at high production volumes and to assess future technology scenarios. Integral to this effort has been the development of a system configuration (in conjunction with Argonne National Laboratories), specification of performance parameters and catalyst requirements, development of representative component designs and manufacturing processes for these components, and development of a comprehensive bill of materials and list of purchased components. The model, data, and component designs have been refined based on comments from the Freedom Car Technical Team and fuel cell system and component developers.

One of the biggest barriers to commercialization of fuel cell vehicles is the high cost of materials and manufacturing of fuel cell components. Precious metal materials in the membrane electrode assemblies (MEAs) account for more than 17 percent of the total cost of polymer electrolyte membrane (PEM) fuel cell systems. Precious metals such as platinum may also be required for fuel processing catalysts. The Department of Energy (DOE) is addressing the important issue of the cost of fuel cell components by supporting R&D projects aimed at improving the performance of fuel cells which would lead to reduced platinum loading, as well as developing low-cost automated industrial processes for the manufacture of electrodes and MEAs. Other projects include development of a supply-demand elasticity model. The long term reserves and availability of platinum is a serious issue facing the commercial viability of fuel cell vehicles.

The potential peaking of world conventional oil production and the possible imperative to reduce carbon emissions will put great pressure on vehicle manufacturers to produce more efficient vehicles, on vehicle buyers to seek them out in the marketplace, and on energy suppliers to develop new fuels and delivery systems. Four cases for stabilizing or reducing light vehicle fuel use, oil use, and/or carbon emissions over the next 50 years are presented. Case 1 - Improve mpg so that the fuel use in 2020 is stabilized for the next 30 years. Case 2 - Improve mpg so that by 2030 the fuel use is reduced to the 2000 level and is reduced further in subsequent years. Case 3 - Case 1 plus 50% ethanol use and 50% low-carbon fuel cell vehicles by 2050. Case 4 - Case 2 plus 50% ethanol use and 50% low-carbon fuel cell vehicles by 2050. The mpg targets for new cars and light trucks require that significant advances be made in developing cost-effective and very efficient vehicle technologies.

After about a decade of considerable investments in polymer electrolyte fuel cell (PEMFC) and in solid oxide fuel cell (SOFC) technology, both are being actively considered for vehicle applications. The two vehicle applications being most actively considered for fuel cells are propulsion (mainly for PEMFC) and auxiliary power (for both PEMFC and SOFC). For all transportation applications, fuel cells promise the benefits of clean and quiet operation, potentially low maintenance and high efficiency, and ultimately greater utility to drivers and passengers. Initial system and vehicle prototypes have started to demonstrate some of these benefits, but much technology development is still needed before commercialization can occur. Not surprisingly then, there are serious hurdles to be overcome if fuel cells are to become true competitors for internal combustion engines (ICEs) in automotive applications.

The vast majority of cars and small trucks are sold with factory installed air conditioning (approximately 80% in 1989). For electric vehicles to succeed in the marketplace, air conditioning will need to be offered as optional equipment, along with adequate heating and defrosting systems. While providing the level of cooling performance expected by vehicle operators, it is important that the power consumption of the air conditioning systems used in electric vehicles be minimized, to minimize penalties to vehicle range and performance. This paper summarizes the design and performance of several air conditioning systems that have been developed for electric vans over the past two years, including systems based largely on standard automobile air conditioning components and more advanced systems using high performance heat transfer components and a variable speed refrigerant compressor.

The vast majority of cars and small trucks are sold with factory installed air conditioning (approximately 80% in 1989). For electric vehicles to succeed in the marketplace, air conditioning will need to be offered as optional equipment, along with adequate heating and defrosting systems. While providing the level of cooling performance expected by vehicle operators, it is important that the power consumption of the air conditioning systems used in electric vehicles be minimized, to minimize penalties to vehicle range and performance. Due to the ongoing CFC-12 phase-out, air conditioning systems intended for EV applications beyond the early 1990's must use an environmentally acceptable alternative refrigerant. This paper summarizes the design of a variable speed Scroll compressor based prototype air conditioning system for an electrically powered mini-van. The system refrigerant is HFC-134a and high performance heat transfer components are utilized.

The Partnership for a New Generation of Vehicles (PNGV) is linking the research efforts of a broad spectrum of U.S. Federal agencies and laboratories with those of the domestic auto manufacturers in pursuit of three specific, interrelated goals: 1) reduce manufacturing production costs and product development times for all car and truck production; 2) pursue advanced technologies for near-term vehicle improvements that increase fuel efficiency and reduce emissions of standard vehicles; and 3) within the next decade, develop a new class of vehicle that will achieve up to three times the fuel efficiency of today's comparable vehicle, and, at the same time, cost no more to own and drive than today's automobile, maintain performance, size, and utility of comparable vehicles, and meet or exceed safety and emission requirements.

Arthur D. Little in conjunction with the Department of Energy and the Illinois Department of Commerce and Community Affairs are developing an ethanol fuel processor for fuel cell vehicles. Initial studies were carried out on a 25 kWe catalytic partial oxidation (POX) reformer to determine the effect of equivalence ratio, steam to carbon ratio, and residence time on ethanol conversion. Results of the POX experiments show near equilibrium yields of hydrogen and carbon monoxide for an equivalence ratio of 3.0 with a fuel processor efficiency of 80%. The size and weight of the prototype reformer yield power densities of 1.44 l/kW and 1.74 kg/kW at an estimated cost of $20/kW.

Industrial grade ethanol, in concentrations ranging from 130 proof to 200 proof, can be used as a feedstock for a 50kWe advanced fuel processor developed by Arthur D. Little, Inc. for fuel cell vehicles. At 180 proof concentration, hydrated ethanol showed no performance degradation compared with both 200 proof (pure) ethanol and E95 (95% ethanol and 5% gasoline) at equivalence ratios ranging from 3.0 to 4.0. Environmental benefits associated with the use of ethanol in fuel cell power systems include its production from renewable biological sources, low toxicity in the event of an accidental spill, and recycling of carbon dioxide released by the process back to the plant matter used as ethanol feedstock. Cost savings associated with the use of hydrated ethanol are expected to include lower production costs, lower distribution costs, and lower powerplant costs due to the possibility of system simplification.

A study was conducted to determine the potential reduction in automotive fuel consumption based on the use of innovative systems and improved components. Technological areas investigated were: spark ignited engines with and without turbocharging, electronic feedback controlled fuel injection with duel bed catalytic converters, stratified charge combustion, light weight diesels, lock-up torque converters, continuously variable ratio transmission, tires aerodynamic drag, vehicle weight, engine accessories and optional equipment. Standard and compact-size 1973 model year vehicles were selected for analysis using a computer-simulation program to predict fuel usage and performance with and without incorporation of the improvements. In addition estimates were made as to whether modified vehicles complied with study constraints such as emission, safety, noise and user requirements.