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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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All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Impacts and emerging research opportunities in Vehicle-Grid Integration for transportation: A review

This review provides a comprehensive examination of Vehicle-Grid Integration (VGI) technologies and their impacts on transportation systems, with a particular emphasis on the transportation-energy nexus. It systematically explores how VGI affects key transportation applications such as charging infrastructure planning, electric vehicle (EV) routing, smart charging coordination, shared mobility, and dynamic pricing. By synthesizing recent literature from both transportation and energy systems perspectives, this study highlights how advanced methodologies, such as reinforcement learning, game theory, and optimization techniques, are used to model the complex interactions between EVs, mobility patterns, and distributed energy systems. Furthermore, the review also identifies critical challenges, including behavioral factors, data limitations, and system scalability. Drawing on these insights, the paper outlines emerging research opportunities to support the design of integrated, resilient, and user-centric VGI solutions that advance sustainable mobility and energy system efficiency.

Charging coordination↗
DOE OSTI2021

Improving Resilience of Bus Bunching Holding Strategy through a Rolling Horizon Approach

Providing public transportation with quality service is critical to attracting more passengers to the system. However, high-demand routes are prone to the so-called bus bunching -- a tendency of buses to group as a consequence of variations in travel times and demands. Bus holding is applied to overcome this effect. In this study, we present a novel method for bus holding in which the control law is based only on the buses' position using a computationally efficient rolling horizon approach. The method uses similar inputs as linear control approaches while not increasing significantly the computational time. However, the method overcomes key a weakness of the linear control approach thanks to the explicit constraint handling that always ensures the control action effectiveness. Simulation experiments in a validation case and a model-specific for a bus rapid transit line in Curitiba, Brazil showed a reduced holding time and improved resilience, delivering more than 20% reduction in delay time accounting for the on-board and station delays.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2020

An Optimization-Based Planning Tool for On-Demand Mobility Service Operations

Regions worldwide are adopting and exploring low-speed automated electric shuttle (AES) service as an on-demand shared mobility service in dense geofenced urban areas. Building on this concept, the National Renewable Energy Laboratory (NREL) recently developed the Automated Mobility District (AMD) toolkit. The AMD toolkit—comprising of a travel micro-simulation model and an energy estimation model—estimates the mobility and energy impacts of a given shuttle configuration within an AMD. Early-stage AMD deployments need to find optimal operational configurations that include: (a) passenger capacity of an AES, (b) time-dependent routes, and (c) fleet size (AES units) to satisfy the demand for the region. This research extends the AMD toolkit functionality by developing an optimization-based planning module that will assist in the operations of AES units. We developed a constrained mixed-integer program accounting for passenger waiting time, battery range, and passenger capacity of AES units. For scalability, we demonstrated the Tabu search-based solution technique for a real-world network—a proposed AMD deployment in Greenville, South Carolina, USA. Compared to rule-based operations, our developed solution yields higher travel time and energy savings for the network at different demand levels. The sensitivity analyses for waiting time thresholds indicate nonlinearity in the system performance, underscoring the need to meet shared-use mobility user-level expectations. The developed optimization framework can be adapted and extended to accommodate different categories of shared-use on-demand mobility services.

ADVANCED PROPULSION SYSTEMS,ENERGY PLANNING, POLIC↗
DOE OSTI2020

Joint optimal scheduling for electric vehicle battery swapping-charging system based on wind farms

Insufficiencies in charging facilities limit the broad application of electric vehicles (EVs). In addition, EV can hardly represent a green option if its electricity primarily depends on fossil energy. Considering these two problems, this paper studies a battery swapping-charging system based on wind farms (hereinafter referred to as W-BSCS). In a W-BSCS, the wind farms not only supply electricity to the power grid but also cooperate with a centralized charge station (CCS), which can centrally charge EV batteries and then distribute them to multiple battery swapping stations (BSSs). The operational framework of the W-BSCS is analyzed, and some preprocessing technologies are developed to reduce complexity in modeling. Then, a joint optimal scheduling model involving a wind power generation plan, battery swapping demand, battery charging and discharging, and a vehicle routing problem (VRP) is established. Then a heuristic method based on the exhaustive search and the Genetic Algorithm is employed to solve the formulated NP-hard problem. Numerical results verify the effectiveness of the joint optimal scheduling model, and they also show that the W-BSCS has great potential to promote EVs and wind power.

17 WIND ENERGY↗
DOE OSTI2024

CO2 Transport Planning Database

The CO2 Transport Planning Database v3.0 is a geospatial resource, containing over 70 gigabytes of data representing critical considerations for the spatial routing of pipelines and transport of CO2, from source to sink. Considerations include state-specific legislation, land use requirements, existing infrastructure, and hazard prevention areas. Built to support strategic domestic energy transport planning and development, more than 60 layers of this database have been weighted (Weight fields) according to current legislation and pipeline construction recommendations. Weighted values range from zero to one, where zero represents potentially more acceptable areas for transport based on the various considerations, and a value of one represents areas that should be avoided. This geospatial database provides a baseline for the Smart CO2 Transport Planning Tool.

Boundaries↗
NASA NTRS1994

A Permutation Engine Switching Node

We describe an asynchronous, strictly non-blocking crossbar node topology and distributed routing algorithm that is particularly suited to optoelectronic implementation.

Permutation engine permutation node topology routi↗
NASA NTRS2015

Assessment of a National Airspace System Airborne Rerouting Tool

This paper presents the assessment of a National Airspace System airborne rerouting tool. The tool implements NASA’s Dynamic Weather Routes concept for wind-corrected flying-time savings during convective weather activity. A description of the system, as applicable to the entire United States airspace is provided, and results are presented demonstrating benefits of such a system from various Centers and airlines’ perspectives. Three cases for selection of reroute-return capture fix, which prevent unrealistically large controller clearances are presented. Results are shown for potential time- and fuel-savings (over 134,000 minutes and 4.2 million lbs. of fuel for over 35,000 proposed reroutes) and sector congestion reduction (over 121 hours in congested sectors) for all 20 Centers. The data used were for 30 days with highest delays attributable to convective weather from April to October of 2014. Other results show the evaluation of the maneuver or reroute start point (a parameter representing the amount of coordination time needed), which highlight the need for a controller-pilot data link. A data link would help achieve higher savings. The results for persistence time, beyond which the time-savings dwindle quickly, help determine the maximum coordination time required for each Center. Finally, an assessment from a current National Operations Manager at the Air Traffic Control System Command Center of the FAA is documented. Those suggestions could improve the efficiency of the air transportation system, especially with the expected improvements in the traffic flow management infrastructure. Currently, one industry partner and one airline are assessing this technology for commercial operational use.

Benefits Assessment↗
NASA NTRSDate not supplied

Exercising Prediction Validation Methods for Analysis of Quiet Supersonic Overflight

En route noise certification procedures for quiet supersonic aircraft are in development under the International Civil Aviation Organization for a proposed standard that could enable civil supersonic overland flight. While these quiet supersonic aircraft do not exist yet, methods are being developed and evaluated using existing N-wave empirical datasets and low-boom simulation datasets. One potential aspect of future certification methods is the ability to use a validated prediction model to predict the certification noise level under reference day weather conditions. Methods to validate predictions, such as the two-sample t-test, Fisher’s combined probability test, two-sample Kolmogorov-Smirnov test, and equivalence testing, have been exercised and modified for this application. While some methods compare mean values, others compare values across the distribution, and a combination of methods can be used. The methods were applied to a subset of an N-wave dataset to demonstrate the applicability and identify potential areas for improvement. Atmospheric turbulence variability was included as a factor in these analyses through KZKFourier propagation simulations with parameters matching actual flights and weather conditions. Results are presented for six noise metrics (PL, ASEL, BSEL, DSEL, ESEL, and ISBAP), and plans to expand the analyses are discussed.

sonic boom↗
DOE OSTI2020

Panel Session 145: Challenges and Opportunities in Establishing a System for Transportation of SNF/UNF

Issues associated with establishing a SNF Transportation System in the U.S. are complex. In part, this is because in the US when discussing SNF, there are two distinct categories. The two categories represent significant differences in ownership, transportation-regulator, and even the physical characteristics of the SNF. Specifically, the physical differences in the SNF include size of the rods, associated quantities to be shipped, cladding material, and radionuclide content/enrichment. The first is commercial SNF (i.e., that associated with nuclear power plants), owned by utilities, until a permanent repository is built with DOE obligated by law to then assume the responsibility for shipping and ownership of the SNF. Since no-permanent repository currently exists, most commercial SNF is stored near the reactor in which it was installed, hence requiring no shipments. Although current shipments of commercial SNF are very limited, the few that do occur are generally performed to support a utilities SNF consolidation effort utility and for post irradiation examination/testing. However, with approximately 83,000 metric tons currently being stored at more than 70 sites around the U.S., when a permanent repository becomes available, the required number of shipments will be extensive. The second category is DOE and research reactor fuel. These fuel rods are generally much smaller in length than commercial fuel rods, with the quantity of rods transported in a shipment significantly less than the number of rods in a typical commercial fuel assembly. Currently, most of the SNF shipments within the U.S come from this category. DOE is currently managing about 2500 metric tons of heavy metal of SNF. This panel focused on updates and status of transportation of SNF/UNF. Panelists provided updates and information on continuing impacts, risk assessment, equipment (rail cars, handling, securement), possible rail routing, and proposed inspection equipment/routing prior to shipments. Panelists with presentations: Preparing for Nuclear Waste Transportation (Daniel Ogg); Challenges and Opportunities in Establishing a System for Transportation of SNF/UNF (Kathy Langan); UNF Transportation: Challenges and Opportunities (Michael Valenzano)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

Remediation of Temporary Storage Sites in Support of the Port Hope Area Initiative - 20295

The Port Hope Area Initiative is a community-based solution for the long-term management of historic low level radioactive waste (LLRW) resulting from 60 years of uranium and radium processing operations in the Town of Port Hope which is located in Ontario, Canada. The Eldorado refinery, on the north shore of Lake Ontario, began refining radium-226 from pitchblende ore, later transitioning to the refining of uranium. Through the history of the operation, LLRW was deposited throughout the town of Port Hope as a result of fugitive emissions from the plant and/or through the re-use of process residues as building material and backfill. Historical clean-up activities conducted in the late 1970's involved the remediation of approximately 400 properties and the relocation of 100,000 cubic metres of contaminated soil to a disposal facility in Chalk River operated by Atomic Energy of Canada Limited (AECL). Owing to space limitations at that disposal facility, any LLRW identified through construction monitoring since that time has been stored in the community at three temporary storage sites located throughout the town. These include: the Centre Pier mound that contained approximately of 19,800 m{sup 3} of LLRW-impacted soil that originated from the construction of a new water treatment plant; two mounds located at a licensed storage facility containing LLRW obtained from residential clean-up activities (11,000 m{sup 3}); and a small pad adjacent to the municipal sewage treatment plant containing 2200 m{sup 3} of LLRW-containing sludge. With the construction of a new long-term waste management facility (LTWMF) that has been designed to house all of the LLRW identified within Port Hope, the three sites were early candidates for remediation. The clean-up of the three temporary storage sites was a significant milestone for the Port Hope Area Initiative. After a decade of planning and consultation, this work represents the first sites in the municipality to be remediated with the waste being safety removed and transferred to the newly constructed LTWMF. This paper discusses the challenges associated with the clean-up activities for these three sites and the strategies employed to address those challenges. These included weather-related challenges, owing to the seasons over which the work was conducted as well as those associated with working within a closely-knit community. Canadian Nuclear Laboratories (CNL), working on behalf of the federal government, has worked diligently to develop a positive and trusting relationship with the community. Consequently, the successful execution of this project needed to be sensitive to, and respectful of the needs of the community. In addition to the usual Health, Safety and Environment training, project staff received community awareness training that spoke to the history of this community-based initiative and the expected behavior when working within the community. Transportation routes were defined based on safety and the need to minimize disruption to local traffic while haul-times where scheduled around school bus hours to enhance public safety. The successful completion of this first of many remediation projects to be completed under the Port Hope Area Initiative reflected years of careful planning. Nevertheless, there were a number of 'lessons learned' that have been applied on other ongoing projects be completed under the Port Hope Area Initiative. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

State Policies on Access to Vaccination Services for Low-Income Adults

Importance State vaccination benefits coverage and access for adult Medicaid beneficiaries vary substantially. Multiple studies have documented lower vaccination uptake in publicly insured adults compared with privately insured adults. Objective To evaluate adult Medicaid beneficiaries’ access to adult immunization services through review of vaccination benefits coverage in Medicaid programs across the 50 states and the District of Columbia. Design, Setting, and Participants A public domain document review with supplemental semistructured telephone survey was conducted between June 1, 2018, and June 14, 2019, to evaluate vaccination services benefits in fee-for-service and managed care organization arrangements for adult Medicaid beneficiaries in the 50 states and the District of Columbia (total, 51 Medicaid programs). Exposures Document review of benefits coverage for adult immunization services and supplemental survey with validation of document review findings. Main Outcomes and Measures Benefits coverage for adult Medicaid beneficiaries and reimbursement amounts for vaccine purchase and administration. Results Public domain document review was completed for all 51 jurisdictions. Among these, 44 Medicaid programs (86%) validated document review findings and completed the survey. Only 22 Medicaid programs (43%) covered all 13 Advisory Committee on Immunization Practices–recommended adult immunizations under both fee-for-service and managed care organization arrangements. Most fee-for-service arrangements (37 of 49) reimbursed health care professionals using any of the 4 approved vaccine administration codes; however, 8 of 49 programs did not separately reimburse for vaccine administration to adult Medicaid beneficiaries. Depending on administration route, median reimbursement for adult vaccine administration ranged from $\$9.81$ to $\$13.98$ per dose. Median per-dose reimbursement for adult vaccine purchase was highest for 9-valent human papillomavirus vaccine ($\$204.87$) and lowest for Haemophilus influenzae type b vaccine ($\$18.09$). Median reimbursement was below the private sector price for 7 of the 13 included vaccines. Conclusions and Relevance Even in programs with complete vaccination benefits coverage, reimbursement amounts to health care professionals for vaccine purchase and administration may not fully cover vaccination provision costs. Reimbursement amounts below costs may reduce incentives for health care professionals to vaccinate low-income adults and thereby limit Medicaid adult beneficiary access to vaccination.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2023

Materials Design Directions for Solar Thermochemical Water Splitting

The sustainable, economical production of molecular hydrogen is a crucial component of a net zero-greenhouse-gas-emissions future. Solar thermochemical water splitting (STWS) offers a renewable route to hydrogen with the potential to help decarbonize several industries, including transportation, manufacturing, mining, metals processing, and electricity generation, as well as provide sustainable hydrogen as a chemical feedstock. STWS uses high temperatures generated from concentrated sunlight or other sustainable means for high-temperature heat to produce hydrogen and oxygen from steam. For example, in its simplest form of a two-step thermochemical cycle, a redox-active metal oxide is heated to ≈1700-2000 K, driving off molecular oxygen while producing oxygen vacancies in the material. The reduced metal oxide then cools (ideally with the extracted heat recuperated for re-use) and, in a separate step, comes into contact with steam, which reacts with oxygen vacancies to produce molecular hydrogen while recovering the original state of the metal oxide. Despite its promising use of the entire solar spectrum to split water thermochemically, the current estimated cost of hydrogen produced via STWS is ≈4-6× the U.S. Department of Energy (DOE) Hydrogen Shot target value of $1/kg. One contributing approach to bridging this cost gap is the design of new materials with improved thermodynamic properties to enable higher efficiencies. The state-of-the-art (SOA) redox-active metal oxide for STWS is ceria (CeO 2 ), due to its close to optimal, although too high, oxygen vacancy formation enthalpy and large configurational and electronic entropy of reduction. However, ceria requires high operating temperatures and its efficiency is insufficient. Therefore, efforts to increase the efficiency of STWS cycles have focused on further optimizing oxygen vacancy formation enthalpies and augmenting the reduction entropy via substitution or doping and materials discovery schemes. Examples of the latter include the perovskites BaCe 0.25 Mn 0.75 O 3 and (Ca,Ce)(Ti,Mn)O 3 . These efforts and others have revealed intuitive chemical principles for the efficient and systematic design of more effective materials, such as the strong correlation between the enthalpies of crystal bond dissociation and solid-state cation reduction with the enthalpy of oxygen vacancy formation, as well as configurational entropy augmentation via the coexistence of two or more redox-active cation sublattices. The purpose of this chapter is to prepare the reader with an up-to-date account of STWS redox-active materials, both the SOA and promising newcomers, as well as to provide chemically intuitive strategies for improving their cycle efficiencies through materials design – in conjunction with ongoing efforts in reactor engineering and gas separations – to reach the cost points for commercial viability. First, we will introduce the thermodynamics of STWS using a two-step, metal-oxide, thermochemical cycle with economics in mind. We also will compare the pros and cons of processes that do or do not involve phase changes. Second, we will describe the qualities that make ceria the SOA STWS redox-active material, as well as its limitations. Third, we will survey some of the most promising candidates to date in the search for materials to supplant ceria, emphasizing the post-ternary, metal-oxide-perovskite alloys. Lastly, we will enumerate and discuss the following materials design directions for STWS redox-active materials: crystal reduction potentials as a proxy for oxygen vacancy formation enthalpies, engineering the electronic and configurational entropy of reduction via f-shells and simultaneous redox, and vetting materials stability via temperature-dependent phase diagrams and melting-point prediction.

08 HYDROGEN↗
DOE OSTI2020

Kirigami-Inspired Self-Assembly of 3D Structures

Self-assembly of 3D structures introduce an attractive and scalable route to realize reconfigurable and functionally capable mesoscale devices without human intervention. A common approach for achieving this is to utilize stimuli-responsive folding of hinged structures, which requires the integration of different materials and/or geometric arrangements along the hinges. It is also demonstrated that the inclusion of Kirigami cuts in planar, hingeless bilayer thin sheets can be used to produce complex 3D shapes in an on-demand manner. Nonlinear finite element models are developed to elucidate the mechanics of shape morphing in bilayer thin sheets and verify the predictions through swelling experiments of planar, millimeter-scaled PDMS (polydimethylsiloxane) bilayers in organic solvents. Building upon the mechanistic understandings, The transformation of Kirigami-cut simple bilayers into 3D shapes such as letters from the Roman alphabet (to make “ADVANCED FUNCTIONAL MATERIALS”) and open/closed polyhedral architectures is experimentally demonstrated. A possible application of the bilayers as tether-less optical metamaterials with dynamically tunable light transmission and reflection behaviors is also shown. As the proposed mechanistic design principles could be applied to a variety of materials, this research broadly contributes toward the development of smart, tetherless, and reconfigurable multifunctional systems.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Structural Instability in Electrically Stressed, Oxygen Deficient BaTiO 3 Nanocrystals

The dynamics of oxygen vacancies under external stimuli dominates the performance of many solid-state devices, including capacitors, oxide memristors, anionic conductors, etc. By means of in-situ Transmission Electron Microscopy, we found in BaTiO 3 perovskite nanocrystals that formation of oxygen vacancies due to electrical stressing renders the oxide amorphizable under electron beam illumination, suggesting the presence of a threshold concentration of oxygen vacancy affecting the structural stability of BaTiO 3 crystals upon high energy radiation. In contrast to the structural change, the resistivity of the nanocrystal seems not liable to the amorphization prior to dielectric breakdown at higher voltage bias. Here, we propose that an increase in oxygen vacancy content promotes oxygen mobility in the perovskite structure allowing electron beam induced electric field to modify the local structural and composition. Our in-situ observations reveal the central role of oxygen vacancies in the structural stability of perovskites which is of paramount importance to their applications in extreme environments and suggest a potential new route to micro-processing perovskite oxides using the electron beam via oxygen vacancy management without severely compromising the electric property.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Manipulating Surface Termination of Perovskite Manganate for Oxygen Activation

For ABO 3 perovskite oxides, one of the key issues limiting their utilization in heterogeneous catalysis is the dominant presence of catalytically inactive A-site cations at the surface. The engineering of B-site terminated perovskites is considered as an effective method to address this issue, especially when dealing with Mn/Co-based perovskite catalysts. However, to date, such a strategy has not been fully successful and remains a major challenge in the field. Herein, a Mn-terminated La 0.45 Sr 0.45 MnO 3 (B-LSM) is successfully synthesized via a one-pot hydrothermal method, in which low-valence Mn ions partially occupy the A site to form the active Mn-excess phase. Additionally, experimental results and theoretical calculations reveal that the presence of the surface Mn termination in B-LSM optimizes the hybrid orbitals of Mn 3d-O 2p and promotes the activation of surface lattice oxygen, where the pristine inert lattice O 2- is evolved into active and stable lattice O 2-x . Such structural optimization significantly reduces the activation energy barriers on going from O 2 ⁻ species to important intermediate O - species during O 2 activation. Moreover, this results in good stability and Pt-like activity for the B-LSM during CO oxidation. This work offers a new chemical route for the design of advanced perovskite-type oxides possessing novel functions.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Ultra‐Uniform Nanocrystalline Materials via Two‐Step Sintering

Abstract Nanocrystalline materials with superior properties are of great interest. Much is discussed about obtaining nanograins, but little is known about maintaining grain‐size uniformity that is critical for reliability. An especially intriguing question is whether it is possible to achieve a size distribution narrower than what Hillert theoretically predicted for normal grain growth, a possibility suggested—for growth with a higher growth exponent—by the generalized mean‐field theory of Lifshitz, Slyozov, Wagner (LSW), and Hillert but never realized in practice. Following a rationally designed two‐step sintering route, it has been made possible in bulk materials by taking advantage of the large growth exponent in the intermediate sintering stage to form a uniform microstructure despite residual porosity, and freezing the grain growth thereafter while continuing densification to reach full density. The bulk dense Al 2 O 3 ceramic thus obtained has an average grain size of 34 nm and a size distribution much narrower than Hillert's prediction. Bulk Al 2 O 3 with a grain‐size distribution narrower than the particle‐size distribution of starting powders is also demonstrated, as are highly uniform bulk engineering metals (refractory Mo and W‐Re alloy) and complex functional ceramics (BaTiO 3 ‐based alloys with superior dielectric strength and energy capacity).

Dong, Yanhao↗