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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 1,711 records · Page 95

ENERGY DISPERSIVE DIFFRACTION TOMOGRAPHY OF SHARK VERTEBRAL CENTRA

Shark vertebrae and their centra (vertebral bodies) are high-performance structures able to survive millions of cycles of high amplitude strain despite lacking a repair mechanism for accumulating damage. Shark centra consist of mineralized cartilage, a biocomposite of bioapatite (bAp), and collagen, and the nanocrystalline bAp's contribution to functionality remains largely uninvestigated. Using the multiple detector energy-dispersive diffraction (EDD) system at 6-BM-B, the Advanced Photon Source, and 3D tomographic sampling, the 3D functionality of entire centra were probed. Immersion in ethanol vs phosphate-buffered saline produces only small changes in bAp d-spacing within a great hammerhead centrum. EDD mapping under in situ loading was performed an entire blue shark centrum, and 3D maps of bAp strain showed the two structural zones of the centrum, the corpus calcareum and intermedialia, contained opposite-signed strains approaching 0.5%, and application of similar to 8% nominal strain did not alter these strain magnitudes and their spatial distribution.

Park, Jun-Sang↗

Advanced Distributed Wind Turbine Controls Series: Part 3-Wind Energy in Grid-Connected Deployments – Microgrids, Infrastructure Resilience, and Advanced Controls Launchpad (MIRACL)

In recent years the technical ability and requirement for distributed wind turbines to provide grid support services beyond maximum energy production has increased. Ancillary services leveraged through advance controls of a wind turbine support grid reliability and resilience. One ancillary service that is significant to a grid-connected wind turbine deployment is fault ride through (FRT) in response to the voltage and frequency events in the power system. As part of the Microgrids, Infrastructure Resilience, and Advanced Controls Launchpad (MIRACL) this paper demonstrates, through desktop simulations, the wind turbine's FRT capabilities to support stable grid operation. We establish that the wind turbine models exceed FRT performance requirements stipulated in IEEE 1547-2018, regarding interconnection and interoperability of distributed energy resources. Utilizing a standalone CART2 (600 kW) wind turbine connected to the NREL's Flatirons Campus grid, we study voltage and frequency FRT utilizing various test cases. One of the test cases under study is a Category III voltage fault defined in IEEE 1547-2018 and derived from CA Rule 21. Some distributed wind turbines were unable to connect to the grid following the Rule 21 enforcement in California. Even if this is not a general requirement elsewhere, the grid codes might evolve in this direction. This study illustrates how a distributed wind turbine can provide some of these FRT services and enable a pathway toward a higher contribution of renewable energy in a distribution grid.

17 WIND ENERGY↗

Resolution of Electronic and Structural Factors Underlying Oxygen-Evolving Performance in Amorphous Cobalt Oxide Catalysts

Non-noble-metal, thin-film oxides are widely investigated as promising materials for catalyzing oxygen evolution reactions (OER). Cobalt oxide thin-films that are electrochemically formed in the presence of borate (CoBi) and phosphate (CoPi) serve as important reference catalysts for assessing correlations between oxyhydroxide domain structures with corresponding electronic properties and OER performance. Here, we present a comparison of CoPi and CoBi thin-film catalysts by a combination of advanced X-ray electronic and vibrational spectroscopies of L-edge synchrotron X-ray absorption (XAS), resonant X-ray emission (RXES), resonant inelastic X-ray scattering (RIXS), resonant Raman (RR) scattering, and high-energy X-ray pair distribution function (PDF) analysis. A detailed spectral analysis is presented and identifies relationships between the OER performance and electronic and molecular-type domain structures. XAS shows that CoBi is composed essentially exclusively of cobalt in octahedral coordination, while CoPi contains approximately 17% tetrahedral Co(II), with the remainder in octahedral coordination. Oxygen-mediated 4 p -3 d hybridization through Co-O-Co bonding was detected by RXES and the inter-site dd excitation was observed by RIXS in CoBi, but not in CoPi. RR shows that CoBi resembles a disordered layered LiCoO 2 -like structure while Co- Pi is amorphous. Distinct domain models in the nanometer range for CoBi and CoPi have been proposed on the basis of the PDF analysis coupled to XAS data. In conclusion, the observed differences provide important implications for the enhancement factors in OEC performance.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Delivering Clean Air in Denver: Propane Trucks and Infrastructure in Mail Delivery Application

In 2021, Drive Clean Colorado, a Denver-based Clean Cities coalition, initiated the deployment of five Class 6 medium-duty propane autogas delivery trucks into a United States Postal Service (USPS) mail delivery contractor fleet with the goal of providing a proof-of-concept demonstration for mail delivery fleets nationwide. Funded by the U.S. Department of Energy's Office of Energy Efficiency & Renewable Energy, the project, titled "Delivering Clean Air in Denver: Propane Trucks and Infrastructure in Mail Delivery Application," enabled the purchase and deployment of the propane-powered trucks, refueling infrastructure, and supporting analysis by the National Renewable Energy Laboratory (NREL). Key objectives of the analysis included calculating the propane vehicles' emissions reductions, analyzing the costs and operational performance of the propane fleet compared to conventional diesel-powered vehicles, and evaluating the viability of propane as a clean and cost-effective alternative to conventional diesel trucks (AFDC 2023b, 2023c). The primary goal of the project was to demonstrate alternative fuel vehicles in a mail transport application and evaluate the viability of propane as a clean and cost-effective alternative to conventional diesel trucks. This proof-of-concept demonstration is expected to lead to improved understanding of the performance attributes, costs, and operational issues to inform technology adoption decisions, helping to spur market transformation toward lower-emission truck fleets. By reducing the risk of first adoption, potential exists to transform the U.S. Postal Service (USPS) mail delivery system into a lower-carbon national fleet. This technical report details the vehicle duty cycle characterization and fleet cost and performance comparison performed by the National Renewable Energy Laboratory, in addition to estimated emissions reductions for delivery operations.

33 ADVANCED PROPULSION SYSTEMS↗

Wheel configurations for combined energy storage and attitude control systems

Integrated power and attitude control system (IPACS) studies performed over a decade ago established the feasibility of simultaneously storing electrical energy in wheels and utilizing the resulting momentum for spacecraft attitude control. It was shown that such a system possessed many advantages over other contemporary energy storage and attitude control systems in many applications. More recent technology advances in composite rotors, magnetic bearings, and power control electronics have triggered new optimism regarding the feasibility and merits of such a system. This paper presents the results of a recent study whose focus was to define an advanced IPACS and to evaluate its merits for the Space Station application. Emphasis is given to the selection of the wheel configuration to perform the combined functions. A component design concept is developed to establish the system performance capability. A system-level trade study, including life-cycle costing, is performed to define the merits of the system relative to two other candidate systems. It is concluded that an advanced IPACS concept is not only feasible but offers substantial savings in mass and life-cycle cost.

Oglevie, R. E.↗

Theoretical and Experimental Studies in Accelerator Physics

This report describes research supported by the US Dept. of Energy Office of High Energy Physics (OHEP), performed by the UCLA Particle Beam Physics Laboratory (PBPL). The UCLA PBPL has, over the last two decades-plus, played a critical role in the development of advanced accelerators, fundamental beam physics, and new applications enabled by these thrusts, such as new types of accelerator-based light sources. As the PBPL mission is broad it is natural that it has been grown within the context of the accelerator science and technology stewardship of the OHEP. Indeed, steady OHEP support for the program has always been central to the success of the PBPL; it has provided stability, and above all has set the over-arching themes for our research directions, which have producing over 500 publications (>120 in high level journals). While other agency support has grown notably in recent years, permitting more vigorous pursuit of the program, it is transient by comparison. Beyond permitting program growth in a time of flat OHEP budgets, the influence of other agency missions is found in push to adapt advanced accelerator methods to applications, in light of the success the field has had in proof-of-principle experiments supported first by the DoE OHEP. This three-pronged PBPL program — advanced accelerators, fundamental beam physics and technology, and revolutionary applications — has produced a generation of students that have had a profound affect on the US accelerator physics community. PBPL graduates, numbering 28 in total, form a significant population group in the accelerator community, playing key roles as university faculty, scientific leaders in national labs (two have been named Panofsky Fellows at SLAC), and vigorous proponents of industrial application of accelerators. Indeed, the development of advanced RF, optical and magnet technology at the PBPL has led directly to the spin-off company, RadiaBeam Technologies, now a leading industrial accelerator firm. We note also that PBPL graduates remain as close elaborators for the program after leaving UCLA. The UCLA PBPL program is a foremost developer of on-campus facilities, such as the Neptune and Pegasus Laboratories, providing a uniquely strong environment for student-based research. In addition, the PBPL is a strong user of off-campus national lab facilities, such as SLAC FACET and NLCTA, and the BNL ATF. UCLA has also vigorously participated in the development of these facilities. The dual emphases on off- and on-campus opportunities permit the PBPL to address in an agile way a wide selection of cutting-edge research topics. The topics embraced by this proposal illustrate this program aspect well. These include: GV/m dielectric wakefield acceleration/coherent Cerenkov radiation experiments at FACET (E-201) and the ATF; synergistic laser-excited dielectric accelerator and light source development; plasma wakefield (PWFA) experiments on “Trojan horse” ionization injection (FACET E-210), quasi-nonlinear PWFA at BNL and the production at Neptune high transformer ratio plasma wakes; the inauguration of a new type of RF photoinjector termed “hybrid” at UCLA, and application to PWFA; space-charge dominated beam and cathode/near cathode physics; the study of advanced IFEL systems, for very high energy gain and utilization of novel OAM modes; the physcis of inverse Compton scattering (ICS), with applications to e+ production and γγ colliders; electron diffraction; and advanced beam diagnostics using coherent imaging techniques. These subjects are addressed under the leadership of PBPL director Prof. James Rosenzweig in Task A, and Prof. Pietro Musumeci in Task J, which was initiated following his OHEP Outstanding Junior Investigator award.

43 PARTICLE ACCELERATORS↗

High Efficacy Green LEDs by Polarization Controlled MOVPE

Amazing performance in GaInN/GaN based LEDs has become possible by advanced epitaxial growth on a wide variety of substrates over the last decade. An immediate push towards product development and worldwide competition for market share have effectively reduced production cost and generated substantial primary energy savings on a worldwide scale. At all times of the development, this economic pressure forced very fundamental decisions that would shape huge industrial investment. One of those major aspects is the choice of epitaxial growth substrate. The natural questions are to what extend a decision for a certain substrate will limit the ultimate performance and to what extent, the choice of a currently more expensive substrate such as native GaN could overcome any of the remaining performance limitations. Therefore, this project has set out to explore what performance characteristic could be achieved under the utilization of bulk GaN substrate. Our work was guided by the hypotheses that line defects such as threading dislocations in the active region should be avoided and the huge piezoelectric polarization needs to be attenuated – if not turned off – for higher performing LEDs, particularly in the longer wavelength green and deep green portions of the visible spectrum. At their relatively lower performance level, deep green LEDs are a stronger indicator of relative performance improvements and seem particular sensitive to the challenges at hand.

36 MATERIALS SCIENCE↗

Interphasial engineering for Ni-rich NMC cathode materials

Ni-rich LiNi 1-x-y Mn x CoyO 2 , (NMC: 1-x-y ≥ 0.6) are promising cathode materials for lithium-ion batteries (LIBs) due to high reversible capacity and low cost. However, the fast capacity decay and voltage fading caused by interphasial instability requires improvement. The unstable cathodeelectrolyte interphase (CEI) and transition metal (TM) dissolution at higher voltages can lead to the drastic deterioration of electrochemical performance. In this review, recent approaches to novel electrolyte and additive design, cathode engineering including artificial CEI, and doping/coating on the surface of particles or the whole electrode are comprehensively summarized. In conclusion, the importance of multi-model and multi-scale characterization methods in understanding the effects of interphasial chemistry on battery performance is highlighted.

25 ENERGY STORAGE↗

A Real-Time Greedy-Index Dispatching Policy for using PEVs to Provide Frequency Regulation Service

This article presents a real-time greedy-index dispatching policy (GIDP) for using plug-in electric vehicles (PEVs) to provide frequency regulation services. A new service cost allocation mechanism is proposed to award PEVs based on the amount of service they provided, while considering compensations for delayed-charging and reduction of battery lifetime due to participation of the service. The GIDP transforms the optimal dispatch problem from a high-dimensional space into a one-dimensional space while preserving the solution optimality. When solving the transformed problem in real-time, the global optimality of the GIDP solution can be guaranteed by mathematically proved “indexability”. Because the GIDP index can be calculated upon the PEV’s arrival and used for the entire decision making process till its departure, the computational burden is minimized and the complexity of the aggregator dispatch process is significantly reduced. Finally, simulation results are used to evaluate the proposed GIDP, and to demonstrate the potential profitability from providing frequency regulation service by using PEVs.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Building America Case Study: Conway Street Apartments, Greenfield, Massachusetts (Fact Sheet)

While single-family, detached homes account for 63% of households (EIA 2009); multi-family homes account for a very large portion of that remaining housing stock, and this fraction is growing. Through recent research efforts, CARB has been evaluating strategies and technologies that can make dramatic improvements in energy performance in multi-family buildings

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

A Cyber-Physical System for Freeway Ramp Meter Signal Control Using Deep Reinforcement Learning in a Connected Environment

Freeway bottlenecks such as on-ramp merging areas account for about 40% of recurring freeway congestion. It is generally agreed that building more roads and adding more lanes to existing infrastructure does not solve the congestion problem, and so dynamic traffic control measures offer a more cost-effective alternative. Ramp meters, traffic signal devices that regulate traffic flow entering freeways, are among the most effective measures to mitigate congestion at on-ramp merging areas on freeways. The confluence of deep reinforcement learning (RL) and connectivity provides a possible solution to advance ramp meter signal control. Deep RL is a group of machine-learning methods that enables an agent learning from the environment to improve its performance. In this study, three deep RL methods-proximal policy optimization (PPO), Ape-X deep Q-network (DQN), and asynchronous advantage actor-critic agents (A3C)-are explored for ramp meter signal control to maximize vehicle speed and traffic throughput, as well as to minimize energy consumption and emissions at freeway on-ramp merging areas in a connected environment. The low computational requirement and scalability of deep RL for deployment make it a powerful optimization tool for time-sensitive applications such as ramp meter signal control. The results of this study show that deep RL methods yield superior performance to both a fixed-time controller and ALINE A, a state-of-the-art feedback controller.

ADVANCED PROPULSION SYSTEMS,MATHEMATICS AND COMPUT↗

Advanced Computing Annual Report 2024

In fiscal year (FY) 2024, the National Renewable Energy Laboratory (NREL) took a major leap forward with the completed full buildout of Kestrel, the Office of Energy Efficiency and Renewable Energy's newest high-performance computing (HPC) system. Kestrel is already supporting science across the portfolio, bringing roughly 44 petaflops of computing power, which is more than five times the capacity of our previous supercomputer, Eagle. By delivering greater GPU capacity, Kestrel enables faster progress in artificial intelligence (AI) and opens new avenues in energy research - from defining long-term planning scenarios to accommodate a growing power system to material discovery to improving energy efficiency in photovoltaics (PV). Across the portfolio, research is being accelerated by Kestrel's impressive power. During FY24, 427 projects and more than 700 researchers used NREL's HPC, supporting the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy across 13 funding areas. Through these collaborations, researchers produced more than 450 technical outputs, including 195 articles in peer-reviewed publications, pushing the boundaries of science and engineering. This year's report features new sections spotlighting the expanding roles of Artificial Intelligence and Accelerated Computing. We also introduce an early career section to celebrate the accomplishments of our up-and-coming researchers, whose pioneering work is shaping the future of energy. We hope you enjoy the new insights and discoveries highlighted in these pages.

97 MATHEMATICS AND COMPUTING↗

Integrated Power and Attitude Control Systems for Space Station

Integrated Power and Attitude Control Systems (IPACS) studies performed over a decade ago established the feasibility of simultaneously storing electrical energy in wheels and utilizing the resulting momentum for spacecraft attitude control. It was shown that such a system possessed many advantages over other contemporary energy storage and attitude control systems in many applications. More recent technology advances in composite rotors, magnetic bearings, and power control electronics have triggered new optimism regarding the feasibility and merits of such a system. The paper presents the results of a recent study whose focus was to define an advanced IPACS and to evaluate its merits for the Space Station application. A system and component design concept is developed to establish the system performance capability. A system level trade study, including life-cycle costing, is performed to define the merits of the system relative to two other candidate systems. It is concluded that an advanced IPACS concept is not only feasible, but offers substantial savings in mass, and life-cycle cost.

Oglevie, R. E.↗

Additively manufactured refractory high-entropy alloys with superior radiation resistance

Refractory high-entropy alloys (RHEAs) are promising candidates for next-generation nuclear and high-temperature applications. Among many approaches to manufacture RHEAs, additive manufacturing (AM) represents the most recent and advanced metal manufacturing method which allows near-net-shape manufacturing to reduce material waste and post-processing time. However, performance of AM RHEAs under complex irradiation conditions remains largely unexplored. Here, in this study, we demonstrate for the first time the response of directed energy deposition (DED) AM quaternary RHEAs (HfTaVW, CrTaVW) subjected to sequential dual-beam ion irradiation, consisting of helium pre-implantation followed by high-dose heavy ion bombardment. Compositions of DED AM RHEAs were selected using Monte Carlo (MC) simulations based on a cluster expansion (CE) Hamiltonian parameterized by density functional theory (DFT). Post-irradiation microstructural characterization revealed that the AM RHEA maintained remarkable stability, with suppressed helium bubble growth and reduced defect accumulation compared to conventional alloys. Even at high doses (∼100 dpa), the alloy exhibited no void swelling, a low density of dislocation loops, and no evidence of severe degradation. These results highlight the intrinsic ability of AM-derived microstructures and multicomponent chemistry to synergistically mitigate irradiation effects. Our findings establish AM RHEAs as a class of materials with superior resistance to radiation damage under conditions relevant to advanced fusion and fission environments and demonstrate the importance of sequential ion beam studies in evaluating their long-term performance.

36 MATERIALS SCIENCE↗

A Comprehensive Approach to Measure the Efficiency of Freight Transport: Freight Mobility Energy Productivity (F-MEP) Metric

Freight travel accounts for a major share of the energy consumed in the transportation sector in any country, and the United States is no exception. Understanding and modeling freight movement is critical, particularly in the context of capturing the impact of emerging technologies on freight travel and its externalities. The domain of freight modeling and forecasting is gaining pace in the recent years, but advancement in comprehensive freight performance metrics is still lagging. Conventional freight performance metrics such as truck-miles, ton-miles, or value-miles are unidimensional and aggregated in nature, making them unsuitable to accurately capture the impact of emerging transportation trends on the performance of freight systems. Addressing this research need, this paper presents the 'Freight Mobility Energy Productivity' metric to quantify freight performance of current as well as future freight systems, accounting for various costs associated with freight transport. The proposed metric was implemented using data from the Freight Analysis Framework along with other published sources, which shows intuitive results in quantifying freight performance. Further, a scenario analysis exercise was conducted to test the capability of the metric in tracking improvements in system-level freight efficiency as a result of vehicle powertrain technology improvement. Results of the scenario analysis reinforce confidence that the proposed metric can be used as a decision support tool in assessing the efficiency of existing as well as future freight trends and technologies.

25 ENERGY STORAGE↗

Experimental Photoionization Cross-section Measurements in the Ground and Metastable State Threshold Region of Seplus

Absolute photoionization cross-section measurements are reported for Se{sup +} in the photon energy range 18.0-31.0 eV, which spans the ionization thresholds of the {sup 4}S{sub 3/2} ground state and the low-lying {sup 2}P{sub 3/2, 1/2} and {sup 2}D{sub 5/2, 3/2} metastable states. The measurements were performed using the Advanced Light Source synchrotron radiation facility. Strong photoexcitation-autoionization resonances due to 4p {yields} nd transitions are seen in the cross-section spectrum and identified with a quantum-defect analysis.

43 PARTICLE ACCELERATORS↗

Electrochemically driven phase transformation for high-efficiency heat pumping

To reduce energy consumption and improve energy utilization in space conditioning, advanced heat pumping technologies are needed. The chemical looping heat pump (CLHP) is a promising thermodynamic cycle that has theoretically shown the potential to achieve a cooling coefficient of performance (COP c ) increase of over 20% relative to conventional vapor compression systems. In this paper, the key process of the CLHP is experimentally demonstrated, and the system performance and non-ideal behavior are predicted using the component-level models. The results show the feasibility of electrochemical phase change of a working fluid; the peak COP c was 7.64 with a cooling capacity of 3.6 mW (cooling density of 2.57 W m -2 ) at both sink and source temperature of 23°C based on laboratory experiments. The COP c can theoretically reach up to 13 at a temperature lift of 15°C as long as an electrochemical cell can achieve a greater degree of conversion.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Human Factors and Modeling Methods in the Development of Control Room Modernization Concepts

nuclear power plants. Although the nuclear industry has made steady improvement in outage optimization, each day of a refueling outage still represents an opportunity to save millions of dollars and each day an outage extends past its planned end date represents millions of dollars that may have been spent unnecessarily. Reducing planned outage duration or preventing outage extensions requires careful management of the outage schedule as well as constant oversight and monitoring of work completion during the outage execution. During a typical outage, there are typically more than 10,000 activities on the schedule that, if not managed efficiently, may cause expensive outage delays. Management of outages currently relies largely on paper-based resources and general-purpose office software. A typical tool currently used to monitor work performance is a burn-down curve, where total remaining activities are plotted against the baseline schedule to track bulk work completion progress. While these tools are useful, there is still considerable uncertainty during a typical outage that bulk work progress is adequate and therefore a lot of management time is spent analyzing the situation on a daily basis. This paper describes recent advances made in developing a framework for the design of visual outage information presentation, as well as an overview of the scientific principles that informed the development of the visualizations. To test the utility of advanced visual outage information presentation, an outage management dashboard software application was created as part of the Department of Energy’s Advanced Outage Control Center project. This dashboard is intended to present all the critical information an outage manager would need to understand the current status of a refueling outage. The dashboard presents the critical path, bulk work performance, key performance indicators, outage milestones and metrics relating current performance to historical performance. Additionally, the dashboard includes data analysis tools to allow outage managers to drill down into the underlying data to understand the drivers of the indicators.

99 GENERAL AND MISCELLANEOUS↗