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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 631 records · Page 35

There's No Place Like Home: Residential Parking, Electrical Access, and Implications for the Future of Electric Vehicle Charging Infrastructure

In March 2021, the cumulative sale of plug-in electric vehicles (PEVs), including plug-in hybrid electric vehicles (PHEV) and battery electric vehicles (BEV), reached 1.8 million in the United States (Argonne National Laboratory 2021). However, PEV adoption is still in its infancy; its market share has just reached around 3% of new light-duty vehicle (LDV) sales by the end of 2020 (Alliance for Automotive Innovation 2021). Current trends suggest that PEV market share in the United States is increasing. The U.S. Energy Information Administration's (EIA's) 2020 Annual Energy Outlook forecasts PEV registrations to exceed 8 million vehicles by 2030 (AEO 2020). PEV adoption is expected to be led by states that are regulating the sale of zero emission vehicles (ZEVs) (California Air Resources Board). California continues to push for more aggressive ZEV regulations; the state recently issued an executive order aimed at 100% of LDV sales being ZEVs by 2035 (Office of Governor Newsom). At the federal level, the Biden administration has shown great ambition in encouraging broader electric vehicle (EV) adoption, including setting the goal of installing 500,000 new chargers nationwide (The White House 2021). Access to charging infrastructure is consistently cited as one of the primary barriers to the increased sale of PHEVs and BEVs (Carley et al. 2019). In the United States, PEV charging options are often described using a pyramid structure, with residential charging as the foundation, workplace charging in the middle, and public charging on top (Figure 1). The existing electricity system, which generates, transmits, and distributes electric fuel to residential households, has helped PEVs partially overcome the "chicken and egg" conundrum that has haunted other alternative fuels. Viable home access to electric charging is also an important equity issue, because non-residential PEV charging options (e.g., workplace or public charging stations) are generally more expensive. Households without residential charging access may experience higher total cost of PEV ownership if non-residential charging options are more costly.

33 ADVANCED PROPULSION SYSTEMS↗

DE‐SC0022708 RESEARCH PERFORMANCE FINAL REPORT

GismoPower’s Final Research Report documents the outcomes of a DOE SBIR Phase II project focused on advancing the MEGA® (Mobile Electricity Generating Appliance), a trailerable, plug-in solar canopy appliance designed to deliver appliance-class electricity generation for homes, small businesses and renters. The project’s core objective was to remove the technical and regulatory barriers that have historically prevented plug-in solar systems from being safely certified, permitted, and interconnected in the United States.

14 SOLAR ENERGY↗

Safety Related Concerns with Installation and Use of Switch-Rated Plug/Receptacle Combinations in Lieu of Metal-Enclosed Disconnect Switches

The manufacturers of Nationally Recognized Testing Laboratory (NRTL) listed, switch-rated, plug and receptacle combinations tout their convenience, reliability, efficiency, and compliance with both the National Fire Protection Association (NFPA) 70®, National Electric Code (NEC), and National Fire Protection Association 70E®, The Standard for Electrical Safety in the Workplace, as advantages to using these products in lieu of traditional metal-enclosed disconnect switches. The purpose of this paper is to raise awareness of several unintended consequences that can result when replacement involves high energy cord and plug connected equipment. This paper describes several possible issues in complying with the NFPA 70 Articles 110 and 400 and NFPA 70E Articles 110 and 130 that should be considered when using load rated plug/receptacle combinations. This paper is intended to address high energy circuits typically associated with 480 volt pin and sleeve type connections in applications where incident energy levels may exceed 1.2 calories/centimeter² (cal/cm²).

99 GENERAL AND MISCELLANEOUS↗

Electric Vehicle Basics

Electric vehicles (EVs) use electricity as their primary fuel or to improve the efficiency of conventional vehicle designs. EVs include all-electric vehicles, also referred to as battery electric vehicles (BEVs), and plug-in hybrid electric vehicles (PHEVs). In colloquial references, these vehicles are called electric cars, or simply EVs, even though some of these vehicles still use liquid fuels in conjunction with electricity. EVs are known for providing instant torque and a quiet driver experience. Other types of electric-drive vehicles not covered here include hybrid electric vehicles, which are powered by a conventional engine and an electric motor that uses energy stored in a battery that is charged by regenerative braking, not by plugging in, and fuel cell electric vehicles, which use a propulsion system similar to electric vehicles, where energy stored as hydrogen is converted to electricity by the fuel cell.

ADVANCED PROPULSION SYSTEMS↗

Electric Vehicle Basics (French Translation)

Electric vehicles (EVs) use electricity as their primary fuel or to improve the efficiency of conventional vehicle designs. EVs include all-electric vehicles, also referred to as battery electric vehicles (BEVs), and plug-in hybrid electric vehicles (PHEVs). In colloquial references, these vehicles are called electric cars, or simply EVs, even though some of these vehicles still use liquid fuels in conjunction with electricity. EVs are known for providing instant torque and a quiet driver experience. Other types of electric-drive vehicles not covered here include hybrid electric vehicles, which are powered by a conventional engine and an electric motor that uses energy stored in a battery that is charged by regenerative braking, not by plugging in, and fuel cell electric vehicles, which use a propulsion system similar to electric vehicles, where energy stored as hydrogen is converted to electricity by the fuel cell. This is the French translation of NREL/FS-5400-87125.

ADVANCED PROPULSION SYSTEMS,DIRECT ENERGY CONVERSI↗

T–x diagrams for the CO 2 –H 2 O system: The importance of water content in CO 2 transportation for carbon capture and storage

Abstract When water is present in a CO 2 pipeline, corrosion or plugging can occur due to the formation of liquid water or gas hydrate, respectively. Understanding how corrosion and hydrate plugging can be avoided is important for enhanced oil recovery and carbon dioxide capture and storage processes. If the CO 2 is sufficiently dried prior to transportation, the formation of these problematic free‐water phases can be avoided. In this work, isobaric T–x diagrams were developed from the P–T diagram for the CO 2 –H 2 O binary system. Pressures ranging from just below the lower quadruple point to above the lower critical end point were studied. These diagrams are meant to give the reader a better conceptual understanding of how the water composition in CO 2 –H 2 O mixtures will influence phases that form at different temperatures and pressures. The diagrams are analyzed from the perspective of flow assurance in CO 2 transportation.

Wadsworth, Lindsey A.↗

Damage progression and failure of SiC/SiC composite tubes under hard-contact radial expansion

The response of silicon carbide (SiC) fiber-reinforced SiC matrix (SiC/SiC) composite cladding to mechanical interaction with fissile fuel is a knowledge gap that must be overcome to design and assess SiC-based cladding systems for advanced nuclear applications. This study developed the relevant mechanical testing capability and identified the failure behavior and the critical microstructural features and processing defects. Sections of SiC composite tube were subjected to a modified expansion-due-to-compression (EDC) test in an X-ray computed tomography microscope: a polyurethane plug pressed surrogate Al 2 O 3 into the inner walls of the SiC/SiC composite tubes to achieve hard contact. A pure EDC test with just a polyurethane plug was also performed as a reference. Through the use of displacement fields, digital volume correlation revealed inhomogeneous deformation fields in the tubes, even for pure EDC, which was related to the inherent defects in the structure. Deep learning–aided segmentation and systematic data analysis revealed that the presence of inhomogeneous deformation applied by the hard contact was exaggerated by the presence of inner surface imperfections left behind from the matrix densification process. In conclusion, the findings provide insights into the applications, highlighting the necessity for improvements in inner surface roughness and the incorporation of localized contacts in pellet–cladding mechanical interaction computational models.

Composites↗

Quantifying the impacts of micro- and mild- hybrid vehicle technologies on fleetwide fuel economy and electrification

Micro- and mild-hybridization (jointly labeled as M-HEV) is gaining popularity as a cost-effective technology for fuel economy improvement, but whether and how M-HEV may compete against less efficient conventional internal combustion engine vehicles (ICEV), more efficient full hybrid electric vehicles (HEV), and plug-in electric vehicles (PEV) is not well understood. As such, this study aims at evaluating the impact of the market adoption of M-HEV on the average fuel economy of the new vehicle fleet and on the sales share of PEVs. The study reviews recent sales trends and market forecasts, and uses published estimates of manufacturing cost and fuel economy of M-HEV with an existing discrete choice model (Market Acceptance of Advanced Automotive Technologies or MA3T) to project the market penetration and impacts of M-HEV under different scenarios of M-HEV choice positions, designed to enhance conclusion robustness. It is found that among engine-based powertrain choices, micro-HEV appears to be the most cost-effective, followed by ICEVs, mild-HEV and finally full HEVs. M-HEV technologies are likely to improve fleetwide average fuel economy without significant adverse effects on sales of plug-in electric vehicles, and are likely to remain highly competitive outside PEVs through 2050.

33 ADVANCED PROPULSION SYSTEMS↗

Gas hydrate deposit formation in transient flowloop tests and mitigation with a surface treatment

Thermodynamic and thermal mitigation strategies are traditionally utilized to prevent gas hydrate formation but may be rendered ineffective for certain unplanned, extended shut-in scenarios. Unfortunately, the current knowledge regarding transient gas hydrate formation has been extremely limited to only a few studies and unable to address this complex issue adequately. This work, conducted in a lab-scale flowloop, aims to add to the understanding of this area by delving into the implications of transient conditions on gas hydrate formation mechanisms, while also exploring a possible mitigation strategy of a surface treatment. Specifically, the effects of phase separation on gas hydrate formation locations, transportability, and plugging are presented for an oil-dominated system. An omniphobic surface treatment is shown to affect initial gas hydrate deposition and its wall adherence strength, as well as the overall plugging outcome. Overall, this work combines observational information with process data measurements to provide a better understanding of phase separated gas hydrate systems and passive deposition mitigation strategies. This can further aid advanced gas hydrate modeling efforts, which currently do not adequately address transient flow effects on phase separation/dispersion. Here, it offers representative gas hydrate testing for coatings, which have exclusively been limited to non-flowing and/or bench-scale analysis, to give confidence in their potential application as advanced deposition prevention tools.

03 NATURAL GAS↗

Evaluating offshore legacy wells for geologic carbon storage: A case study from the Galveston and Brazos areas in the Gulf of Mexico

In this article, federal offshore waters in the Gulf of Mexico are of interest for large-scale geologic carbon storage (GCS). However, more than 80,000 offshore oil and gas wells exist in the region, which could impact the integrity of sealing intervals. In this study, we propose a screening methodology for ranking offshore legacy wells based on the challenge they may present to GCS. The methodology relies on the review of well regulatory records to 1) identify leakage pathways and assess the potential hazards that wells pose to planned GCS operations, 2) evaluate well features that impact the accessibility of wells to determine the feasibility of potential corrective actions, and 3) rank wells based on the overall challenge they may pose for GCS. We demonstrate our framework by evaluating the construction and abandonment of 156 wells across eight areas of interest (AOIs) in shallow federal waters along the Texas Gulf Coast. The majority (99.3 %) of wells considered were constructed and plugged in a manner that did not isolate prospective GCS targets in the Upper and Lower Miocene formations and may potentially require a challenging or uncertain corrective action prior to GCS. Dataset trends suggest that the observed well construction and plugging designs may be common in shallow offshore federal waters along the Texas Gulf Coast. Consequently, operators pursuing offshore GCS projects in the region may consider selecting areas that avoid challenging wells or performing robust evaluations of legacy well leakage risks to plan corrective action prior to CO 2 injection.

58 GEOSCIENCES↗

Evaluating sealability of blended smart polymer and fiber additive for geothermal drilling with the effect of fracture opening size

Geothermal formations often contain extensive fracture networks. These fracture networks contribute to the significant loss of drilling fluids during geothermal drilling. Multiple loss circulation materials (LCM) such as fiber, granules, and pills have been proposed to tackle this problem but with only limited success. Recent advances in materials science have led to the development of thermoset shape memory polymers (SMP) to address the lost circulation problem. In this paper, we evaluate a thermoset SMP performance in sealing near wellbore fractures of different sizes in geothermal wells. The SMP performance was assessed using granite disks and cylindrical granite cores having fracture sizes of 1000 μm and 3000 μm. A static filtration test was performed using cedar fiber, CaCO 3 , and SMP. Results showed cedar fiber performed better than the CaCO 3 ., reducing fluid loss by 89% and improving sealing pressure by 200 psi. A novel dynamic testing unit that allows for high-temperature testing under flowing conditions was used in this study. The analysis showed that 3% by weight SMP and fiber blends could bridge and plug the 1000 μm fracture. For a larger fracture of 3000 μm width, there was a need to increase the weight concentration of the SMP to 6% to plug the fracture opening effectively. We showed the influence of key parameters such as the type of LCM, concentration, and particle size distribution in optimizing the performance of drilling fluid loss treatment.

02 PETROLEUM↗

Heat transfer coefficients of moving particle beds from flow-dependent thermal conductivity and near-wall resistance

Accurate determination of heat transfer coefficients for flowing packed particle beds is essential to the design of particle heat exchangers and other thermal and thermochemical equipment. While such dense granular flows mostly fall into the well-known plug-flow regime, the discrete nature of granular materials alters the thermal transport processes in both the near-wall and bulk regions of flowing particle beds from their stationary counterparts. As a result, heat transfer correlations based on the stationary particle bed thermal conductivity could be inadequate for flowing particles in a heat exchanger. Most earlier works have achieved a reasonable agreement with experiments by treating granular heat transfer media as a plug-flow continuum with a near-wall thermal resistance in series. However, the thermal conductivity values of the continuum were often obtained from measurements on stationary beds owing to the difficulty of flowing bed measurements. In this work, it was found that the properties of a stationary bed are highly sensitive to the method of particle packing and there is a decrease in the particle bed thermal conductivity and increase in the near-wall thermal resistance, measured as an effective air gap thickness, on the onset of particle flow. These variations in thermal conductivity of stationary and flowing particle beds can lead to errors in heat transfer coefficient calculations. Therefore, the heat transfer coefficients for granular flows were calculated using experimentally determined flowing particle bed thermal conductivity and near-wall air gap for ceramic particles – CARBO CP 40/100 (mean diameter = 275 µm), HSP 40/70 (404 µm) and HSP 16/30 (956 µm); at velocities of 5–15 mm·s –1 ; and temperatures of 300–650 °C. The thermal conductivity and air gap values for CP 40/100 and HSP 40/70 were further used to calculate heat transfer coefficients across different particle bed temperatures and velocities for different parallel-plate heat exchanger dimensions. Furthermore, these calculations, which show good agreement with measured HTC values reported in literature, can be used as a guide for heat exchanger designs. Graphical abstract

14 SOLAR ENERGY↗

Modeling charging infrastructure impact on the electric vehicle market in China

The plug-in electric vehicle (PEV) is deemed as a critical technological revolution, and the governments are imposing various vehicle policies to promote its development. Meanwhile, the market success of PEVs depends on many aspects. The study reported herein integrates one’s use of charging infrastructure at home, public place and workplace into the market dynamics analysis tool, New Energy and Oil Consumption Credits (NEOCC) model, to systematically assess the charging infrastructure (home parking ratio, public charging opportunity, and charging costs) impact on PEV ownership costs and analyze how the PEV market shares may be affected by the attributes of the charging infrastructure. Compared to the charging infrastructure, the impact of battery costs is incontrovertibly decisive on PEV market shares, the charging infrastructure is still non-negligible in the PEV market dynamics. The simulation results find that the public charging infrastructure has more effectiveness on promoting the PEV sales in the PEV emerging market than it does in the PEV mature market. However, the improvement of charging infrastructure does not necessarily lead to a larger PEV market if the charging infrastructure incentives do not coordinate well with other PEV policies. Besides, the increase of public charging opportunities has limited motivations on the growth of public PEV fleets, which are highly correlated to the number of public fast charging stations or outlets. It also finds that more home parking spaces can stimulate more sales of personal plug-in hybrid electric vehicles instead of personal battery electric vehicles.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

The role of infrastructure to enable and support electric drive vehicles: A Transportation Research Part D Special Issue

Widespread vehicle electrification appears to be necessary to achieve timely and deep reductions in greenhouse gases (GHG) and pollutant emissions as well as petroleum use in the transportation sector. The lack of a sufficient refuelling infrastructure has defeated many past efforts to promote alternatives to petroleum fuels. The papers in this special issue on the “Role of Infrastructure to Enable and Support Electric Drive Vehicles” address the diverse challenges posed by a transition from fossil-fuelled internal combustion engine vehicles to vehicles powered by electric motors and the special role of refuelling/recharging infrastructure in this transition. Electric drive vehicles are herein considered to be plug-in electric vehicles (PEVs), including plug-in hybrid electric vehicles (PHEVs), battery electric vehicles (BEVs), and hydrogen fuel cell electric vehicles (FCEVs). BEVs and FCEVs are also known as Zero Emission Vehicles (ZEVs) because their propulsion systems produce no tailpipe emissions.

33 ADVANCED PROPULSION SYSTEMS↗

Techno-economic comparison of electrification for heavy-duty trucks in China by 2040

We show that electrification of heavy-duty trucks (HDTs) is critical of achieving sustainability and carbon neutrality in road freight. Based on the total cost of ownership and the life-cycle emissions, the study compared the traditional diesel internal combustion engine vehicle technologies with potential electrification options for HDTs in China, including battery electric vehicle, plug-in hybrid electric vehicle, hydrogen fuel cell vehicle, and battery electric catenary vehicle. Scenario and sensitivity analysis were explored the life-cycle effects of these electrification options in China from 2020 to 2040. It is found that green electricity and green hydrogen are the most important factors influencing the life-cycle emissions of CO 2 , NO X , and PM 2.5 for different HDTs’ electrification options. The plug-in hybrid electric vehicle of HDTs has shown good performance in terms of total cost and carbon emissions, mainly due to the reduced battery capacity and the current grid mix in China.

33 ADVANCED PROPULSION SYSTEMS↗

Computational Study on the Effect of Thermal Boundary Conditions and Axial Aspect Ratio on Catalytic Oxidative Coupling of Methane

Packed-bed reactor models with a large reactor-diameter-to-particle-diameter ratio (N > 10) are commonly used in catalysis research. Their use is underpinned by strong simplifying assumptions including unidirectional plug flow, negligible radial gradients, small axial diffusion, and isothermal operation. However, the complex exothermic–endothermic nature of reactions like oxidative coupling of methane (OCM) coupled with heat transfer from the catalyst surface and convective heat losses from the reactor wall provides an interesting case study to evaluate packed-bed assumptions and understand axial and radial temperature variations that may impact conversion and selectivity. This computational study investigates the effect of thermal boundary conditions on catalyst performance in laboratory OCM reactors (N = ~13) through computational fluid dynamics (CFD) simulation. Further, the 1-D model typically used for modeling plug flow reactors assumes negligible radial temperature and species concentration gradients. This assumption is evaluated for OCM reactors over a range of geometric axial aspect ratios, defined as the reactor length divided by the diameter, comparing the 1-D with 3-D CFD results. 1-D model predictions of catalyst performance start to deviate from the 3-D model predictions as the axial aspect ratio decreases, specifically as diameter increases at constant length. In the work, the 1-D model assumption is only found to be valid for axial aspect ratios higher than 1.6, a result considered to be relevant for all exothermic catalytic reactors.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Investigation of Biomass Fouling on Screw Feeder in Preconversion of Pyrolysis

Biomass is a source of renewable energy and can undergo thermochemical processes to be converted into gaseous and liquid fuels. Thermal decomposition-induced biomass fouling on the screw feeder is a major challenge in preconversion of pyrolysis, leading to plugging of the feed line. Here, this work intends to gain fundamental understanding of the biomass fouling phenomena across the heat gradient on the screw feeder via a combination of materials characterization and thermal simulation. An actual screw feeder that failed because of biomass fouling was examined to reveal the deposit’s morphology, composition, and mechanical properties. Thermal simulations were developed for both the screw feeder and the wood particles being transported using a combined analytical and numerical approach. The simulated temperature profiles correlated well with the deposit observations, based on which potential mitigations were proposed from both the operation and screw design perspectives and supported by preliminary experimental validation.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

An Analysis of Abandoned Oil Well Characteristics Affecting Methane Emissions Estimates in the Cherokee Platform in Eastern Oklahoma

Anthropogenic activities increase methane emissions, contributing to greenhouse gas levels and adversely affecting the environment. Abandoned oil and gas wells potentially leak methane, but data are limited. We analyze methane emissions from abandoned wells (n = 179) in the Cherokee Platform in Oklahoma, a previously unaccounted basin, and compare emissions factors (EFs) to those in the Greenhouse Gas Inventory. We compare the contribution of various characteristics to the propensity for leakage. Higher emissions were observed with shallower wells and with unplugged wells. Plugged wells (n = 20) had an average EF of 96 ± 429 g/day and 65 ± 294 g/day for unplugged wells (n = 159). The majority of wells had no detectable leak. We calculated ethane EFs based on geochemical analysis of gas samples, finding higher EFs for unplugged (1.2 ± 5.5 g/day) versus plugged (0.9 ± 4.6 g/day) wells. The data indicate that in addition to the location of abandoned wells, physical characteristics are necessary to consider in estimating methane emissions.

58 GEOSCIENCES↗