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Previous work has shown that wallboard can be successfully manufactured to contain up to 30% phase change material (PCM), or wax, thus enabling this common building material to serve as a thermal energy storage device. This material was analyzed for passive solar applications and found to save energy with a reasonable pay-back time period. Further evaluations of the wallboard are reported in this paper. This analysis looks at potential applications of PCM wallboard as a load management device and as a comfort enhancer. Results show that the wallboard is ineffective in modifying the comfort level but can provide significant load management relief with no energy penalty. Modifications to typical heating and air-conditioner control strategies were necessary for successful load management.

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.

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.

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.

On April 6, 1984, EPA announced a final rule (40 CFR Part 600, Vol. 49, No. 68) which amended the Federal Fuel Economy Information Program by prescribing adjustment factors for the Federal fuel economy numbers and by establishing a new format for the Federal fuel economy label displayed on new vehicles. This rule, one of over 5, 000 documents printed in the 1984 Federal Register rule section, presents some interesting lessons about development of government regulations. The contents of this rule amended an existing rule, did not have a “major” impact on the economy, and was not considered to be controversial. Nonetheless, this rule represents at least nine years of work, negotiations, and deliberations by Federal and private sector organizations. The history of this rule can provide insight into the Federal rulemaking process, and the forces affecting that process.

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.

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

The Cooperative Automotive Research for Advanced Technology (CARAT) program is designed to accelerate the commercialization of innovative technologies that will overcome barriers to achieving the goals of the Partnership for a New Generation of Vehicles Program. Aimed at harnessing the creativity and capabilities of American small businesses and colleges and universities, this unique technology R&D program seeks to develop and bring advanced technologies into use in production vehicles at a faster rate. CARAT's focus is developing and commercializing technology that overcomes key technical barriers preventing the production of vehicles with ultra-high fuel efficiency. CARAT begins with technologies that already have a firm technical basis and, through a unique three-stage process, ends with fully validated technologies ready for mass production. The program is open to all U.S. entrepreneurs and small businesses, colleges, and universities.

The effects of hybridization on heavy-duty vehicles are not well understood. Heavy vehicles represent a broader range of applications than light-duty vehicles, resulting in a wide variety of chassis and engine combinations, as well as diverse driving conditions. Thus, the strategies, incremental costs, and energy/emission benefits associated with hybridizing heavy vehicles could differ significantly from those for passenger cars. Using a modal energy and emissions model, we quantify the potential energy savings of hybridizing commercial Class 3-7 heavy vehicles, analyze hybrid configuration scenarios, and estimate the associated investment cost and payback time.

In-cylinder blending of gasoline and diesel to achieve reactivity controlled compression ignition (RCCI) has been shown to reduce NOX and PM emissions while maintaining or improving brake thermal efficiency as compared to conventional diesel combustion (CDC). The RCCI concept has an advantage over many advanced combustion strategies in that the fuel reactivity can be tailored to the engine speed and load allowing stable low-temperature combustion to be extended over more of the light-duty drive cycle load range. However, the current range of the experimental RCCI engine map investigated here does not allow for RCCI operation over the entirety of some drive cycles and may require a multi-mode strategy where the engine switches from RCCI to CDC when speed and load fall outside of the RCCI range.

For most air conditioning systems, usually only 85% of the evaporator is effectively used. The other 15% is used to superheat the refrigerant so that the compressor will be protected from liquid slugging, but this practice results in excessive evaporator volume. In mobile air conditioning (MAC) systems where the space available for the evaporator is very limited, the evaporator should be fully used, yet MAC designs have not reflected this need. This study reports on the designing and testing of a novel liquid over-feeding (LOF) MAC system that can use 100% of the evaporator effectively. A LOF system is designed so that not all liquid refrigerant is evaporated in the evaporator. The low-pressure liquid and vapor flow into an accumulator-heat exchanger where the liquid is boiled off by the warm, high-pressure liquid leaving the condenser. This concept not only allows 100% evaporator utilization, but will also reduce system power consumption and improve compressor reliability.

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.

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.

Temperature measurement of internal components and surfaces can enhance understanding of thermal processes that occur during engine operation. Such measurements have typically been made with thermocouples, temperature sensitive paints or plugs, or infrared emission methods. Phosphor thermometry, a non-contact measurement technique, is an alternative that can be applied when more traditional methods are not feasible or are too costly. Recent efforts described in this paper have used phosphor thermometry to measure steady state piston crown temperature in a single cylinder engine. Additional testing with this technique included monitoring intake valve temperature in a multicylinder engine under cold start conditions. Packaging of the optical hardware necessary for this technique was substantially refined during these tests for use in modern engine geometries.

The DOE Office of Heavy Vehicle Technologies (OHVT) focuses its research and development efforts on technologies that are critical to the needs of the U.S. heavy vehicle industry because of the importance of trucks and other heavy vehicles to economic activity and growth. A strategy has been crafted in collaboration with OHVT's industry customers (truck and engine manufacturers, fuel developers/producers, and their suppliers, truck users, and others) that will enable future energy demand of the U.S. heavy vehicle industry to be met, with reduced dependence on imported oil, and without adverse environmental effects. This strategy is centered on the technical strengths of the advanced compression-ignition (Diesel cycle) engine and its potential to use fuels from alternative feedstocks, and to reduce exhaust emissions to very low levels.

This paper describes the results of Phase 1 of the Diesel Emission Control - Sulfur Effects (DECSE) Program. The objective of the program is to determine the impact of fuel sulfur levels on emissions control systems that could be used to lower emissions of nitrogen oxides (NOx) and particulate matter (PM) from vehicles with diesel engines. The DECSE program has now issued four interim reports for its first phase, with conclusions about the effect of diesel sulfur level on PM and total hydrocarbon (THC) emissions from the high-temperature lean-NOx catalyst, the increase of engine-out sulfate emissions with higher sulfur fuel levels, the effect of sulfur content on NOx adsorber conversion efficiencies, and the effect of fuel sulfur content on diesel oxidation catalysts, causing increased PM emissions above engine-out emissions under certain operating conditions.

It is generally recognized chat methanol is the best candidate for long-term replacement of petroleum-based fuels at soma time in the future. The transition from an established fuel to a new fuel, and vehicles that can use the new fuel, is difficult, however. This paper discusses two independent investigations of possible transition uses of methanol, which, when combined, may provide an option for introduction of methanol that takes advantage of the existing industrial base, and provides economic incentives to the consumer. The concept combines the intermediate blends of methanol and gasoline (50%-70% methanol) with the Flexible Fuel Vehicle. In addition to a possible maximum cost effectiveness, these fuels ease vehicle range restrictions due to refueling logistics, and mitigate cold starting problems, while at the same time providing most of the performance of the higher concentration blends.

A methanol and a gasoline vehicle were each subjected to testing under severe short-trip driving conditions. Results show that the cool oil sump temperatures caused more fuel and water to collect in the oil of the methanol vehicle. Protective properties of both vehicles' oils degraded during short trips but rebounded somewhat during a subsequent long trip. Slightly warmer sump temperatures in longer short-trip driving resulted in no methanol dilution in the methanol vehicle's oil, and higher total volatiles contamination in the gasoline vehicle's oil. Freeway driving following the longer short trips promoted less rebound in the degraded oils' protective properties.

There is a need for an efficient, durable technology to reduce NOx emissions from oxidative exhaust streams such as those produced by compression-ignition, direct-injection (CIDI) diesel or lean-burn gasoline engines. A partnership formed between the DOE Office of Advanced Automotive Technology, Pacific Northwest National Laboratory, Oak Ridge National Laboratory and the USCAR Low Emission Technologies Research and Development Partnership is evaluating the effectiveness of a non-thermal plasma in conjunction with catalytic materials to mediate NOx and particulate emissions from diesel fueled light duty (CIDI) engines. Preliminary studies showed that plasma-catalyst systems could reduce up to 70% of NOx emissions at an equivalent cost of 3.5% of the input fuel in simulated diesel exhaust. These studies also showed that the type and concentration of hydrocarbon play a key role in both the plasma gas phase chemistry and the catalyst surface chemistry.