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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 793 records · Page 44
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Multiscale modeling and cinematic visualization of photosynthetic energy conversion processes from electronic to cell scales

We report conversion of sunlight into chemical energy, namely photosynthesis, is the primary energy source of life on Earth. A visualization depicting this process, based on multiscale computational models from electronic to cell scales, is presented in the form of an excerpt from the fulldome show Birth of Planet Earth. This accessible visual narrative shows a lay audience, including children, how the energy of sunlight is captured, converted, and stored through a chain of proteins to power living cells. The visualization is the result of a multi-year collaboration among biophysicists, visualization scientists, and artists, which, in turn, is based on a decade-long experimental-computational collaboration on structural and functional modeling that produced an atomic detail description of a bacterial bioenergetic organelle, the chromatophore. Software advancements necessitated by this project have led to significant performance and feature advances, including hardware-accelerated cinematic ray tracing and instanced visualizations for efficient cell-scale modeling. The energy conversion steps depicted feature an integration of function from electronic to cell levels, spanning nearly 12 orders of magnitude in time scales. This atomic detail description uniquely enables a modern retelling of one of humanity’s earliest stories—the interplay between light and life.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2018

A New Look at Licensing Basis Events for the Molten Salt Reactor Experiment

Southern Company and industry partners have created the Licensing Technical Requirements Modernization Project (LMP) to identify important elements of the US Nuclear Regulatory Commission (NRC) regulatory process that need to be updated or adapted to support advanced non–light water reactors (LWR s). The objectives of the LMP are to identify gaps in the regulatory process for non-LWR designs and to propose solutions based on greater use of risk-informed and/or performance-based practices on a technology-inclusive basis [1] . This project is being coordinated with the Nuclear Energy Institute (NEI) through the Advanced Reactor Working Group.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2026

Defining Electrode-Level Metrics for Enabling Earth-Abundant, Mn-Rich Cathodes: A Technoeconomic Analysis of Experimental Materials

Manganese-rich oxides are attractive options as next-generation, earth-abundant cathodes and significant efforts are being directed toward commercial implementation. We report here an updated techno-economic analysis of the lithium- and manganese-rich (LMR) class of earth-abundant cathodes for electric vehicle applications. BatPaC modeling was used to define the cell-level metrics that must be met for these materials to be cost and energy competitive with the current commercial earth-abundant benchmark, LiFePO 4 , as well as anticipated variations such as LiMn 0.8 Fe 0.2 PO 4 . The model was used to evaluate a high-performance material from the literature and subsequently define R&D targets as the likely limits of practical performance for similar LMR systems. Experimental validation and BatPaC evaluation of an advanced, cobalt-free LMR cell system was also conducted. Results show that the advanced LMR cells come within ∼5% of the defined limits and exceed the energy of LiFe(Mn)PO 4 cells at a similar cost. Excellent cycle-life, low impedance, and low impedance rise were also achieved under the conditions tested and reveal that cobalt is not necessary to achieve high-performance LMR oxides. Although the analysis conducted herein reports on LMR cell systems, the methodology and target values defined for performance metrics easily extend to the evaluation of other systems under consideration as earth-abundant options.

Chen, Jiajun [Argonne National Laboratory (ANL), A↗
DOE OSTI2012

New MEA Materials for Improved DMFC Performance, Durability and Cost

The University of North Florida (UNF), with project partners the University of Florida, Northeastern University, and Johnson Matthey, has recently completed the Department of Energy (DOE) project entitled “New MEA Materials for Improved DMFC Performance, Durability and Cost”. The primary objective of the project was to advance portable fuel cell MEA technology towards the commercial targets as laid out in the DOE R&D roadmap by developing a passive water recovery MEA. Developers at the University of North Florida (UNF) identified water management components as an insurmountable barrier to achieving the required system size and weight necessary to achieve the energy density requirements of small portable power applications. UNF developed an innovative “passive water recovery” MEA for direct methanol fuel cells (DMFC) which provides a path to system simplification and optimization. The passive water recovery MEA incorporates a hydrophobic, porous barrier layer within the cathode electrode, so that capillary pressure forces the water produced at the cathode through holes in the membrane to the anode, as shown in Figure 1. By directly transferring the water from the cathode to the anode, the balance of plant is very much simplified; thus, the need for heavy, bulky water recovery components is eliminated.

08 HYDROGEN↗
DOE OSTI2017

Simulation of Hawaiian Electric Companies Feeder Operations with Advanced Inverters and Analysis of Annual Photovoltaic Energy Curtailment

The Hawaiian Electric Companies achieved a consolidated Renewable Portfolio Standard (RPS) of approximately 26% at the end of 2016. This significant RPS performance was achieved using various renewable energy sources - biomass, geothermal, solar photovoltaic (PV) systems, hydro, wind, and biofuels - and customer-sited, grid-connected technologies (primarily private rooftop solar PV systems). The Hawaiian Electric Companies are preparing grid-modernization plans for the island grids. The plans outline specific near-term actions to accelerate the achievement of Hawai'i's 100% RPS by 2045. A key element of the Companies' grid-modernization strategy is to utilize new technologies - including storage and PV systems with grid-supportive inverters - that will help to more than triple the amount of private rooftop solar PV systems. The Hawaiian Electric Companies collaborated with the Smart Inverter Technical Working Group Hawai'i (SITWG) to partner with the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) to research the implementation of advanced inverter grid support functions (GSF). Together with the technical guidance from the Companies's planning engineers and stakeholder input from the SITWG members, NREL proposed a scope of work that explored different modes of voltage-regulation GSF to better understand the trade-offs of the grid benefits and curtailment impacts from the activation of selected advanced inverter grid support functions. The simulation results presented in this report examine the effectiveness in regulating voltage as well as the impact to the utility and the customers of various inverter-based grid support functions on two Hawaiian Electric distribution substations.

14 SOLAR ENERGY↗
DOE OSTI2017

Advances in electrode materials for Li-based rechargeable batteries

Rechargeable lithium-ion batteries store energy as chemical energy in electrode materials during charge and can convert the chemical energy into electrical energy when needed. Tremendous attention has been paid to screen electroactive materials, to evaluate their structural integrity and cycling reversibility, and to improve the performance of electrode materials. This review discusses recent advances in performance enhancement of both anode and cathode through nanoengineering active materials and applying surface coatings, in order to effectively deal with the challenges such as large volume variation, instable interface, limited cyclability and rate capability. We also introduce and discuss briefly the diversity and new tendencies in finding alternative lithium storage materials, safe operation enabled in aqueous electrolytes, and configuring novel symmetric electrodes and lithium-based flow batteries.

25 ENERGY STORAGE↗
DOE OSTI2022

Understanding Power and Energy Utilization in Large Scale Production Physics Simulation Codes

Power is an often-cited reason for moving to advanced architectures on the path to Exascale computing. This is due to the practical concern of delivering enough power to successfully site and operate these machines, as well as concerns over energy usage while running large simulations. Since accurate power measurements can be difficult to obtain, processor thermal design power (TDP) is a possible surrogate due to its simplicity and availability. However, TDP is not indicative of typical power usage while running simulations. Using commodity and advance technology systems at Lawrence Livermore National Laboratory (LLNL) and Sandia National Laboratory, we performed a series of experiments to measure power and energy usage in running simulation codes. These experiments indicate that large scale LLNL simulation codes are significantly more efficient than a simple processor TDP model might suggest.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2025

Meso-scale modeling of UO2 nuclear fuel to high burnup

To improve the economics of light water reactors for commercial nuclear energy generation, utility operators are seeking to obtain regulatory approval to run UO2 fuel to higher levels of burnup. One potential impediment to obtaining this approval is the phenomenon of fuel fragmentation, relocation, and dispersal (FFRD). FFRD can result when fuel experiences a rapid temperature transient, such as that occurring during a Loss Of Coolant Accident (LOCA). FFRD has historically been most associated with the rim region in UO2 fuel pellets, where the phenomenon of fragmentation is also referred to as pulverization due to the small size of the fragments. More recent evidence suggests that the so-called “dark zone” (due to its appearance in micrographs) that can be observed in the mid-radial regions of high burnup fuel is also susceptible to FFRD. Although empirical fuel performance models have been developed that can adequately predict pulverization in the rim region under typical LWR conditions, a scientific understanding of what underlies fuel restructuring and subsequent FFRD is lacking even in the rim region, and no models are currently available for the behavior the dark zone. To address these challenges, the U.S. Department of Energy’s Nuclear Energy Advanced Modeling and Simulation (NEAMS) program has employed a multi-scale modeling approach to improve scientific understanding and develop new fuel performance models. In this talk, I will focus on meso-scale efforts, which form a crucial link between atomic-scale and engineering-scale models. Phase-field modeling combined with cluster dynamics is used to predict the restructuring process in the rim region. Phase-field fracture modeling, informed by atomistic simulations, is used to predict the onset of pulverization in the rim region. Combining these techniques together allows the extent of rim pulverization to be predicted. The formation and evolution of the dark zone has also been simulated with the phase-field method, using an improved approach to vacancy source term parameterization. The work shows the important impact of microstructure on fuel performance.

fracture↗
DOE OSTI2026

A transfer learning approach to energy-efficient control of small and medium-sized commercial buildings

Model-free reinforcement learning (RL) provides a data-driven and adaptive approach to optimize building energy use while satisfying occupant comfort. This powerful tool does not need any prior knowledge about the environment and system it is optimizing and can adapt its policy based on the changes in captures. Like any other data-driven tool, it faces high training costs due to the extensive agent-environment interactions required to capture long-term building dynamics and user comfort. Transfer learning, particularly policy distillation, offers a promising way to accelerate training by leveraging pretrained RL agents in different building and system types. Here, this study investigates online student distillation, in which the student model updates its neural network weights using outputs from teacher models. The work introduces a student distillation strategy designed for efficient knowledge transfer, along with a teacher selection method that ensures high-quality guidance. The approach is validated using a highly calibrated whole building energy model for a small/medium commercial building test facility. Results show substantial reductions in training time and data requirements while surpassing the performance of ASHRAE Guideline 36, an advanced rule-based control strategy. The distilled RL model required 45% less data and achieved 20% higher cumulative rewards than a state-of-the-art RL model, with faster convergence and lower energy consumption. These outcomes demonstrate that effective transfer learning enables a scalable and data-efficient energy management solution for commercial buildings.

ASHRAE guideline 36↗
NASA NTRS1975

Conceptual design of reduced energy transports

This paper reports the results of a conceptual design study of new, near-term fuel-conservative aircraft. A parametric study was made to determine the effects of cruise Mach number and fuel cost on the 'optimum' configuration characteristics and on economic performance. Supercritical wing technology and advanced engine cycles were assumed. For each design, the wing geometry was optimized to give maximum return on investment at a particular fuel cost. Based on the results of the parametric study, a reduced energy configuration was selected. Compared with existing transport designs, the reduced energy design has a higher aspect ratio wing with lower sweep, and cruises at a lower Mach number. It yields about 30% more seat-miles/gal than current wide-body aircraft. At the higher fuel costs anticipated in the future, the reduced energy design has about the same economic performance as existing designs.

Ardema, M. D.↗
DOE OSTI2017

Microstructures and Microhardness Properties of CMSX-4{sup ®} Additively Fabricated Through Scanning Laser Epitaxy (SLE)

Epitaxial CMSX-4{sup ®} deposition is achieved on CMSX-4{sup ®} substrates through the scanning laser epitaxy (SLE) process. A thorough analysis is performed using various advanced material characterization techniques, namely high-resolution optical microscopy, scanning electron microscopy, energy-dispersive x-ray spectroscopy, x-ray diffraction, and Vickers microhardness measurements, to characterize and compare the quality of the SLE-fabricated CMSX-4{sup ®} deposits to the CMSX-4{sup ®} substrates. The results show that the CMSX-4{sup ®} deposits have smaller primary dendritic arm spacing, finer γ/γ′ size, weaker elemental segregation, and higher microhardness compared to the investment cast CMSX-4{sup ®} substrates. The results presented here demonstrate that CMSX-4{sup ®} is an attractive material for laser-based AM processing and, therefore, can be used in the fabrication of gas turbine hot-section components through AM processing.

36 MATERIALS SCIENCE↗
DOE OSTI2026

Iron surface corrosion in supercritical CO2 at atomic scale investigated by molecular dynamics simulations

Understanding the corrosion behavior of steels in supercritical carbon dioxide (S-CO2) is essential for ensuring the safe application of S-CO2 as a heat-transfer fluid in high-temperature energy systems, including advanced nuclear reactors. In this work, molecular dynamics (MD) simulations using ReaxFF potential are performed to explore the atomic-scale corrosion mechanisms of body-centered cubic iron (BCC-Fe) in S-CO2. The results show that CO2 molecules in S-CO2 decompose at the Fe surface, generating free C and O atoms that form Fe-C and Fe-O bonds and subsequently produce oxides and carbides. Concurrently, Fe atoms dissolve from the surface and diffuse into the S-CO2 region, resulting in interdiffusion of Fe, C and O atoms at the interface. The corrosion-layer thickness calculations show that high pressure and temperature induced by S-CO2 have stronger effects than surface orientation on the corrosion process. In addition, surface Fe atoms undergo substantial displacement under S-CO2 exposure, further accelerating corrosion. When a radiation-induced void is introduced near the Fe surface, the corrosion is enhanced. The void-matrix interface expands the reaction surface area and simultaneously induces corrosion reactions inside the bulk, resulting in a deeper penetration of C and O and thicker corrosion layers. All these results indicate that high-temperature, high-pressure and radiation-induced voids can seriously affect the corrosion of Fe in S-CO2, and must be considered to better use S-CO2 in nuclear facilities.

Li, Wenhua↗
DOE OSTI2021

Challenges for and Pathways toward Li-Metal-Based All-Solid-State Batteries

Solid-state batteries utilizing Li metal anodes have the potential to enable improved performance (specific energy >500 Wh/kg, energy density >1500 Wh/L), safety, recyclability, and potentially lower cost (<$100/kWh) compared to advanced Li-ion systems.1,2 These improvements are critical for the widespread adoption of electric vehicles (EVs) and trucks and could create a short-haul electric aviation industry.1-3 Expectations for solid-state batteries are high, but there are significant materials and processing challenges to overcome.

25 ENERGY STORAGE↗
DOE OSTI2015

The materials genome in action: identifying the performance limits for methane storage

Analogous to the way the Human Genome Project advanced an array of biological sciences by mapping the human genome, the Materials Genome Initiative aims to enhance our understanding of the fundamentals of materials science by providing the information we need to accelerate the development of new materials. This approach is particularly applicable to recently developed classes of nanoporous materials, such as metal–organic frameworks (MOFs), which are synthesized from a limited set of molecular building blocks that can be combined to generate a very large number of different structures. In this Perspective, we describe how a materials genome approach can be used to search for high-performance adsorbent materials to store natural gas in a vehicular fuel tank. Drawing upon recent reports of large databases of existing and predicted nanoporous materials generated in silico , we have collected and compared on a consistent basis the methane uptake in over 650 000 materials based on the results of molecular simulation. The data that we have collected provide candidate structures for synthesis, reveal relationships between structural characteristics and performance, and suggest that it may be difficult to reach the current Advanced Research Project Agency-Energy (ARPA-E) target for natural gas storage.

03 NATURAL GAS↗
DOE OSTI2024

ECP libraries and tools: An overview

The Exascale Computing Project (ECP) Software Technology and Co-Design teams addressed the growing complexities in high-performance computing (HPC) by developing scalable software libraries and tools that leverage exascale system capabilities. As we enter the exascale era, the need for reusable, optimized software solutions that can handle the unique challenges posed by these systems becomes increasingly important. The primary challenges the ECP teams faced were to create software libraries and tools that are performant on exascale architectures and portable and usable across diverse hardware platforms. Efforts addressed issues related to concurrent execution, memory management, and the integration of heterogeneous computing resources, such as GPUs from multiple vendors. The ECP’s strategy involved a structured development process encompassing the creation, optimization, and deployment of software in collaboration with industry, academia, and national laboratories. The project was organized into several technical areas: co-design of domain-specific suites with target applications, programming models and runtimes, development tools, mathematical libraries, data and visualization tools, and software ecosystem and delivery mechanisms. ECP has successfully developed a large portfolio of software libraries and tools that demonstrate significant improvements in performance and scalability on exascale systems. These products have been integrated into the Department of Energy’s computing facilities, supporting various scientific applications and ensuring robust performance across different hardware setups. ECP advancements in software development for exascale computing highlight the importance of a collaborative and adaptive approach to handling next-generation HPC systems complexities. The lessons learned emphasize the need for continuous engagement with end-users and vendors, and the importance of maintaining a balance between innovation and practical implementation. Future efforts will focus on ensuring scalability, keeping pace with rapid hardware advancements, and further enhancing the interoperability and usability of the software ecosystem. In conclusion, subsequent articles in this special issue provide in-depth discussions and case studies into specific library and tool efforts.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2012

Development and Testing of an UltraBattery-Equipped Honda Civic

The UltraBattery retrofit project DP1.8 and Carbon Enriched project C3, performed by ECOtality North America (ECOtality) and funded by the U.S. Department of Energy (DOE) and the Advanced Lead Acid Battery Consortium (ALABC), are to demonstrate the suitability of advanced lead battery technology in Hybrid Electrical Vehicles (HEVs).

25 ENERGY STORAGE↗
DOE OSTI2012

Advanced Post-Irradiation Examination Capabilities Alternatives Analysis Report

An alternatives analysis was performed for the Advanced Post-Irradiation Capabilities (APIEC) project in accordance with the U.S. Department of Energy (DOE) Order DOE O 413.3B, “Program and Project Management for the Acquisition of Capital Assets”. The Alternatives Analysis considered six major alternatives: 1. No Action, 2. Modify Existing DOE Facilities – capabilities distributed among multiple locations, 3. Modify Existing DOE Facilities – capabilities consolidated at a few locations, 4. Construct New Facility, 5. Commercial Partnership, and 6. International Partnerships. Based on the alternatives analysis documented herein, it is recommended to DOE that the advanced post-irradiation examination capabilities be provided by a new facility constructed at the Materials and Fuels Complex at the Idaho National Laboratory.

42 ENGINEERING↗