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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 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Autonomous Strategies for Improved Performance and Reliability of Li‐Ion Batteries

Abstract The battery community has devoted significant effort to improve the performance and reliability of Li‐ion batteries through the development of new materials. The integration of autonomous function provides an alternative strategy to further extend performance. Autonomous material systems mimic the ability of biological systems to self‐protect, sense, regulate, and heal in response to damage and other environmental changes. When incorporated in batteries, these materials enable autonomic restoration of battery performance upon degradation, as well as autonomic shutdown or extinguishment in response to thermal runaway. Successful strategies for improving Li‐ion battery performance include controlled release of microencapsulated functional additives and the integration of self‐healing or adaptive interlayers and binders. These methods have been effective for stabilizing the solid electrolyte interface, preventing battery fires, restoring electrode conductivity, and suppressing Li dendrite growth. Challenges and opportunities exist in the further application of autonomous strategies in the battery environment. A greater variety of encapsulated additives with precise triggered‐release are needed to address specific battery degradation mechanisms. Incorporation of self‐healing polymers in solid‐state batteries facilitates improvement in interfacial and mechanical stability. The integration of autonomous strategies with battery management systems potentially enables enhanced control over multiple battery cycling parameters.

Zhao, Lihong↗
DOE OSTI2021

Tank Side Cesium Removal IXC-150 Cask Detonation Report

A set of experiments were conducted at Los Alamos National Laboratory’s firing point 88 to determine the blast pressure and effects of a stoichiometric gas mixture of Hydrogen (H 2 ) and Nitrous Oxide (N 2 O) on the IXC-150 Storage Pad Vent Stack assemblies. The Lab was asked to design, build, and test the vent stack assemblies using a reaction gas volume of 340 in 3 that mimics the Tank Side Cesium Removal (TSCR) Ion Exchange Column (IXC) assembly. The experimental system with vent stack assembly was designed with input from the Washington River Protection Services (WRPS) to ensure an accurate test setup. The tests were conducted at LANL on the newly built filter/gas assembly at the end of April 2021 timeframe, using WRPS supplied vent stack assemblies and internal HEPA filters. The objective of these tests was to observe that the structural integrity of the vent stack assemblies was maintained and determine the resulting blast overpressures at a distance of 16 and 32 inches from the assembly. All work was performed under the LANL Quality Assurance Program (SD330), using a graded application of ASME NQA-1- 2008/NQA-1a-2009. To ensure that all client quality assurance (QA) expectations were addressed, evaluation of the end data needs was performed and the appropriate controls applied for this work.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2021

Corrosion of novel reactive silver ink and commercial silver-based metallizations in diluted acetic acid

Silver-based metallizations in photovoltaic modules are susceptible to corrosion by acetic acid generated in ethylene vinyl acetate encapsulated modules, resulting in power losses over time. Here, three silver-based metallizations are exposed to diluted acetic acid, in concentrations representative of that found in field-exposed modules. Compositional, morphological, and structural changes of the metallizations are studied over 3000 h of exposure to diluted acetic acid using Raman spectroscopy mapping, X-ray diffraction, and scanning electron microscopy. The three metallizations studied are: 1) a commercial high-temperature fire-through Ag paste, commonly used for Si diffused junction solar cells; 2) a commercial low-temperature paste normally used for silicon heterojunction cells; and 3) a novel low-temperature reactive silver ink shown to be suitable for photovoltaic applications. We find distinct corrosion rates for the high-temperature silver paste and reactive silver ink in the presence of diluted acetic acid. However, the low-temperature silver paste appears to be more corrosion resistant, likely due to a polymer layer that protects the silver particles.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Development of a Nitrogen and Magnesium Oxide based Class A, B & D Suffocating Fire System (SFSS) for Gloveboxes

Testing related to the development and performance of a “Proof of Concept” Nitrogen/Magnesium Oxide Suffocating Fire System (SFSS) was conducted at Fire and Pump Service Group (FPSG) located in Rancho Dominguez, California. The SFSS Engineering Team (SFSSET), consisting of FPSG and Los Alamos National Laboratory (LANL) personnel researched, developed a prototype, and conducted testing to determine effective means to deliver magnesium oxide (MgO) sand into a glovebox (GB) in a class D fire event. The prototypes development also established the effective coverage area of a magnesium oxide suppression system as well as demonstrated that the GB inert atmosphere could be maintained during and after the release of the MgO sand to control Class A, B and D fires. Previous testing conducted on nitrogen based SFSS provided evidence that the nitrogen based SFSS controlled Class A and B fires (Ralph Clayton, Los Alamos National Laboratory, Brandon Troc and Frank Broidy, Fire and Pump Service Group 2020).Final testing was conducted within a mock GB capable of simulating an inert glovebox atmosphere. Testing demonstrated that the inert atmosphere can be maintained during and after discharge of the MgO sand over a coverage area.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2021

Sodium Fire Collaborative Study Progress CNWG Fiscal Year 2021

This report discusses the progress on the collaboration between Sandia National Laboratories (Sandia) and Japan Atomic Energy Agency (JAEA) on the sodium fire research in fiscal year (FY) 2021 and is a continuation of the FY2020 progress report. In this report, we only report the changes made to the current sodium pool fire model in MELCOR. We modified and corrected many control functions to enhance the current model from the FY2020 report. This year’s enhancements relate to better agreement of the suspended aerosol measurement from JAEA’s F7 series tests. Staff from Sandia and JAEA conducted the validation studies of the sodium pool fire model in MELCOR. To validate this pool fire model with the latest enhancement, JAEA sodium pool fire experiments (F7-1 and F7-2) were used. The results of the calculation, including the code-to-code comparisons are discussed as well as suggestions for further model improvement. Finally, recommendations are made for new MELCOR simulations for FY2022.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2023

Compatibility of Wrought Superalloys with Supercritical CO2

Supercritical CO2 (sCO2) power cycles, particularly direct-fired cycles, have the possibility of revolutionizing clean fossil energy with peak temperatures above 700 °C and wrought precipitation strengthened alloys like Haynes 282™ for structural components. At temperatures <650 °C, it would be desirable to use less expensive alloys, however, steels are known to be susceptible to carburization. Laboratory 300 bar sCO2 autoclave results were collected on a range of alloys including less expensive Ni-based alloys like 825 compared to advanced austenitic steels like alloy 709 at 600 °C. Both alloys 825 and 709 formed thin, protective Cr-rich oxides after 1,000 h. Alloy 825 also was exposed for 1,000 h in sCO2 at 800 °C and compared to a range of Ni-based alloys. Comparing alloys 625, 825, and 282, the mass gain increased with increasing alloy Ti content under these conditions. High Al superalloys did not perform significantly better under these conditions at 800 °C.

Pint, Bruce↗
DOE OSTI2025

Probabilistic Resilience-Oriented Assessment Approach for Transmission Networks Under Wildfires

The rising threat of wildfires poses significant challenges to power transmission networks, particularly in areas prone to such disasters. Traditional approaches for wildfire risk assessment neglect some potential wildfire scenarios. Here, this paper introduces a probabilistic resilience-oriented assessment approach for power transmission networks to address this gap. Initially, a probabilistic wildfire model is developed to capture uncertainties in ignition, intensity, and fire spread. Next, a spatiotemporal fragility model is constructed to assess the impact of wildfires on transmission corridors, incorporating Thermal Aging (TA) and Dynamic Thermal Rate (DTR) change. Finally, a comprehensive resilience metric is defined to evaluate system performance, leveraging the fragility model to determine component and system-level resilience. The approach employs a combinatorial enumeration method to generate potential wildfire scenarios, enhanced by an impact-increment-based state enumeration (IISE) method for computational efficiency. The proposed method provides critical insights for identifying system vulnerabilities and developing robust strategies to protect transmission networks from wildfires. The efficacy of this approach is validated through extensive scenarios of the RTS-GMLC system across Southern California, Nevada and Arizona.

Vahedi, Soroush [Univ. of Connecticut, Storrs, CT ↗
DOE OSTI2021

High-Temperature Oxidation of Steels in Direct-Fired CO 2 Power Cycle Environments

We report future direct-fired supercritical CO 2 power cycles require steels resistant to oxidation/corrosion in high-temperature CO 2 environments containing various impurities. Herein we studied the oxidation behavior of 14 candidate steels in a simulated direct-fired CO 2 power cycle environment consisting of 95% CO 2 , 4% H 2 O, 1% O 2 with/without 0.1% SO 2 at 1 atm and 550 °C, 600 °C, 650 °C for up to 2500 hours. Steels with ≥11.5 wt% Cr exhibited at least partial coverage by Cr-rich oxide scales leading to a significant decrease in the oxidation rates in both gases. While SO 2 had little effect on low-Cr steels that formed Fe-rich oxides, it generally worsened performance of high-Cr (> 11.5 wt%) steels by hindering the establishment of a protective Cr-rich oxide. This effect was most pronounced at the lowest temperature of 550 °C, which was attributed to strong preferential adsorption of sulfur-containing species within the oxide at relatively low temperatures.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Durable and Versatile Immobilized Carbonic Anhydrase on Textile Structured Packing for CO 2 Capture

High-performance carbon dioxide (CO 2 )-capture technologies with low environmental impact are necessary to combat the current climate change crisis. Durable and versatile “drop-in-ready” textile structured packings with covalently immobilized carbonic anhydrase (CA) were created as efficient, easy to handle catalysts for CO 2 absorption in benign solvents. The hydrophilic textile structure itself contributed high surface area and superior liquid transport properties to promote gas-liquid reactions that were further enhanced by the presence of CA, leading to excellent CO 2 absorption efficiencies in lab-scale tests. Mechanistic investigations revealed that CO 2 capture efficiency depended primarily on immobilized enzymes at or near the surface, whereas polymer entrapped enzymes were more protected from external stressors than those exposed at the surface, providing strategies to optimize performance and durability. Textile packing with covalently attached enzyme aggregates retained 100% of the initial 66.7% CO 2 capture efficiency over 71-day longevity testing and retained 85% of the initial capture efficiency after 1-year of ambient dry storage. Subsequent stable performance in a 500 h continuous liquid flow scrubber test emphasized the material robustness. Biocatalytic textile packings performed well with different desirable solvents and across wide CO 2 concentration ranges that are critical for CO 2 capture from coal and natural gas-fired power plants, from natural gas and biogas for fuel upgrading, and directly from air.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

Burn severity and vegetation type control phosphorus concentration, molecular composition, and mobilization

Shifting phosphorus (P) dynamics after wildfires can have cascading impacts from terrestrial to aquatic environments. However, it is unclear whether shifts in P composition or P concentration are responsible for changes in P dynamics post-fire. We used laboratory leaching experiments of Douglas fir forest and sagebrush shrubland chars to examine how the potential mobility of P compounds is influenced by different burn severities. Burning produced a 6.9- and 29-fold increase in particulate P mobilization but a 3.8- and 30.5-fold decrease in aqueous P released for Douglas fir forest and sagebrush shrubland, respectively. The mechanisms driving particulate- and dissolved-phase P compound mobilization were contrasting. Phosphorus compound mobilization in the particulate phase was controlled by solid char total P concentrations, while the aqueous phase was driven by solubility changes of molecular species. Nuclear magnetic resonance (NMR) and X-ray absorption near-edge structure (XANES) on the solid chars indicated that organic orthophosphate monoester and diester species were thermally mineralized to inorganic P moieties with burning in both vegetation types, which decreases P solubility. This coincided with the production of calcium- and magnesium-bound inorganic P compounds. With increasing burn severity there were systematic shifts in P concentration and composition – higher-severity chars mobilized P compounds in the particulate phase, although the magnitude of change was vegetation-specific. Our results indicate a post-fire transformation to both the composition of the solid charred material and how P compounds are mobilized, which may influence its environmental cycling and fate.

31P solution-state NMR↗
DOE OSTI2022

Los Alamos National Laboratory Floodplain Assessment for the West Road Post and Cable Fencing Project

The National Nuclear Security Administration (NNSA), a semi-autonomous agency within the U.S. Department of Energy (DOE), is proposing to take action at Los Alamos National Laboratory (LANL) to install post and cable or in-kind barriers along West Road at selected locations near the Los Alamos County ice-skating rink in Los Alamos Canyon (Figure 1). The proposed project is intended to improve vehicular and pedestrian safety on West Road by reducing traffic hazards associated with unsafe roadside parking and reduce wildland fire hazards associated with vehicles driving and parking on vegetation. West Road crosses approximately 0.35 miles (mi.) (1,900 feet (ft.)) of the Los Alamos Canyon floodplain at the bottom of Los Alamos Canyon. Project activities within the floodplain include blocking access to the informal roadside parking along either side of West Road in Los Alamos Canyon.

42 ENGINEERING↗
DOE OSTI2025

PFAS Removal by Ion Exchange Resins: Background and Knowledge Gaps with Respect to the Hanford Site

Per- and polyfluoroalkyl substances (PFAS) have been a rising concern for the past two decades, with the United States Department of Defense and Environmental Protection Agency investing millions of dollars in research into remediation and clean-up technologies. Due to the environmental persistence, toxicity, biological uptake, and ongoing changes in both federal and state regulatory space, understanding the fate and transport of PFAS compounds has been of growing concern to the US Department of Energy (DOE). The DOE’s Hanford Site is investigating historical use of PFAS and will be doing site characterization for PFAS. Thus, PFAS have not yet been identified as a contaminant concern in regulatory documents. Based on historical records that mention the discharge of aqueous film-forming foam containing PFAS and having on-site fire stations (a risk factor for PFAS contamination), it seems likely that environmental releases of PFAS may have occurred. Pump and treat (P&T) remediation is the selected remedy for multiple groundwater contaminant plumes at Hanford. These P&T systems use ion exchange (IX) as a component of aboveground treatment, with the specific resins depending on the target contaminants. There is potential that these IX resins may be able to remove PFAS from groundwater, but investigation is needed to understand affinity/selectivity and removal capacity given the groundwater composition and the operating conditions. This report provides background on PFAS uses and chemistry, then provides a review of IX resin applications for PFAS, identifying knowledge gaps. Recommendations are provided regarding research needed to address knowledge gaps and acquire information needed to propose IX as a future PFAS remediation technology at the Hanford Site, as well as other U.S. Department of Energy sites. Generally, PFAS compounds are fluorinated substances that contain at least one fully fluorinated methyl or methylene carbon – with a few noted exceptions, any chemical with at least a perfluorinated methyl group (–CF3) or a perfluorinated methylene group (–CF2–) is a PFAS. These chemical compounds are characterized as non-biodegradable, non-reactive, non-photolytic, and hydrolysis resistant. This makes them highly recalcitrant within the environment, however polyfluoroalkyl materials are less recalcitrant as the carbon chains contain C–H bonds which are more easily broken than carbon – fluorine (C–F) bonds. The backbone carbon structures are commonly punctuated with a head group, the most well-known of them are perfluorooctanesulfonic acid and perfluorooctanoic acid, which possess a sulfonate and a carboxylate group, respectively. IX resins are marketed for the removal of PFAS from water systems and industrial water, however, the mechanism of removal is not as well understood as for anion or cation removal. A better understanding of the mechanism of removal would enable the development of IX resins that have improved specificity for PFAS removal. Four knowledge gaps were identified: 1) the effect of dissolved ions on the IX resin PFAS removal effectiveness, 2) the effect of additional primary contaminants of concern (PCOCs) or secondary contaminants of concern (SCOCs) on the effectiveness of PFAS via IX resin, 3) the mechanisms of PFAS removal from water, and 4) practical solutions to IX resin regeneration and waste disposal.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2021

Compatibility of Steels in Supercritical CO2 at 450°-650°C

Supercritical CO2 (sCO2) power cycles, particularly direct-fired cycles, have the possibility of revolutionizing clean fossil energy. However, in the lower temperature sections of the cycle, lower cost steels are needed in order to lower the cost of the sCO2 technology. Representative 9 and 12%Cr steels and conventional and advanced austenitic steels are being evaluated at 450-650°C using mass change, bulk carbon (C) content and room temperature tensile properties to determine the maximum use temperatures for both direct- and indirect-fired sCO2 cycles. After 1000 h exposures in research grade (RG) sCO2 at 300 bar and RG sCO2 with 1% O2 and 0.1% H2O additions, the results suggest that increasing the Cr content from 9 to 12% yielded no signficant benefit under these conditions but the higher Cr and Ni contents in S31025 provided better compatibility in RG sCO2 at 650°C but limited benefit at 550°C with impurities. For S31609, the formation of Fe-rich oxide after exposure to RG sCO2 at 650°C resulted in both an increase in the bulk C content and a large drop in room temperature ductility. The evidence suggests thin, protective oxides prevented C ingress in these conditions.

Pint, Bruce↗
DOE OSTI2021

Impact of Non-Steady State Operation on Cooling Water Consumption at Coal- and Natural Gas-Fired Power Plants

Increased renewable energy penetration in the electricity grid in coming decades will result in more frequent cycling at thermal power plants. Simultaneously, thermal power plants may face water scarcity with declining availability of cooling water. Therefore, to enhance thermal power plants’ resiliency to water shortages it is important to understand how non-steady conditions due to cycling will impact cooling water consumption and withdrawal intensity. Non-steady operation at power plants has been previously shown to decrease power plant thermal efficiency. Energy balance models have also demonstrated that a decrease in thermal efficiency is expected to increase cooling water consumption intensity. Furthermore, past work has used operating hours data to show idling and cycling gaps where cooling systems operate more than corresponding generators. As a result, an increase in cycling behavior may impact cooling water consumption and withdrawal intensity. This study uses data from the Energy Information Administration (EIA) and Environmental Protection Agency (EPA) to quantify the impact of cycling cooling water consumption intensity for recirculating cooling systems and withdrawal intensity for once-through cooling systems using energy balance and statistical approaches. In a novel application of a fixed effects model to study the effect of temperature on cooling water consumption and withdrawal intensity, this study finds temperature was consistently expected to increase consumption intensity and withdrawal intensity. Non-steady state conditions do not increase cooling water consumption intensity with statistical significance across unit types. However, additional validation of cooling water data is required to confirm these observed trends due to the sensitivity of these findings to model form and concerns with data quality of the dependent variables, cooling water consumption and withdrawal.

20 FOSSIL-FUELED POWER PLANTS↗
DOE OSTI2025

Fission gas trapped in Chornobyl fuel microparticles reveals details of reactor operations

The isotopic ratios of fission gas would provide important source information of a nuclear fuel sample found in the environment. However, it is believed that during a reactor accident like Chornobyl all fission gas is lost and that the radioactive particles found in the Chornobyl Exclusion Zone today are depleted in gases by the initial explosion and subsequent fire. We disprove this hypothesis by detection and analysis of trapped krypton and xenon in these particles. Our analysis of krypton and xenon isotopes by noble gas mass spectroscopy in combination with resonance ionization mass spectrometry establishes that important information about reactor operations like age, neutron flux and plutonium fission fraction can still be reconstructed from individual micrometer-sized particles even after decades of weathering in the environment.

Chornobyl↗
DOE OSTI2023

South Africa National Cooling Plan

South Africa is committed to preserving the environment and addressing climate change related issues based on science and equity. In 2019, South Africa ratified the Kigali Amendment to the Montreal Protocol to reduce the consumption and production of hydrofluorocarbons (HFCs) to simultaneously protect the ozone layer and contribute to mitigating climate change. In 2015, South Africa also signed the United Nations Framework Convention on Climate Change (UNFCCC) Paris Agreement to fight against climate change and committed to achieve a “peak, plateau and decline” greenhouse gas (GHG) trajectory at a level between 398 and 614 MtCO2e/year by 20301. In 2021 revised target ranges of 398-510 Mt CO 2 -eq for 2025, and 398-440 Mt CO 2 -eq for 2030 were issued, as well as aspiring to reach a net zero carbon economy by 2050. Addressing the environmental impacts of cooling products converges the objectives of these two treaties. Cooling products are the main source of HFC use and they consume a significant amount of electricity produced from emission intensive coal fired power plants. South Africa’s efforts to mitigate global warming can therefore be amplified if the energy efficiency (EE) of cooling products is improved at the same time a refrigerant transition from HFC is considered. Synergistic actions with respect to sustainable cooling access across sectors will have a higher impact than actions taken in isolation.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2023

An Inventory of AI-ready Benchmark Data for US Fires, Heatwaves, and Droughts

Extreme weather events, including fires, heatwaves, and droughts, have significant impacts on earth, environmental, and energy systems. Mechanistic and predictive understanding, as well as probabilistic risk assessment of these extreme weather events, are crucial for detecting, planning for, and responding to these extremes. Records of extreme weather events provide an important data source for understanding present and future extremes, but the existing data needs preprocessing before it can be used for analysis. Moreover, there are many nonstandard metrics defining the levels of severity or impacts of extremes. In this study, we compile a comprehensive benchmark data inventory of extreme weather events, including fires, heatwaves, and droughts. The dataset covers the period from 2001 to 2020 with a daily temporal resolution and a spatial resolution of 0.5°×0.5° (~55km×55km) over the continental United States (CONUS), and a spatial resolution of 1km × 1km over the Pacific Northwest (PNW) region, together with the co-located and relevant meteorological variables. By exploring and summarizing the spatial and temporal patterns of these extremes in various forms of marginal, conditional, and joint probability distributions, we gain a better understanding of the characteristics of climate extremes. The resulting AI/ML-ready data products can be readily applied to ML-based research, fostering and encouraging AI/ML research in the field of extreme weather. This study can contribute significantly to the advancement of extreme weather research, aiding researchers, policymakers, and practitioners in developing improved preparedness and response strategies to protect communities and ecosystems from the adverse impacts of extreme weather events.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2023

Internal carburization and scale formation on austenitic steels in supercritical carbon dioxide

Direct-fired supercritical CO 2 (sCO 2 ) power cycles are being commercialised to revolutionise fossil energy as a low-emission power source. In order to lower the cost of this technology, less expensive steels are needed in the lower temperature segments of the cycle. However, there are concerns about internal carburisation of steels in sCO 2 . A consistent observation is that thin, Cr-rich oxides appear to reduce C ingress compared to thick Fe-rich oxides formed on 9–12% Cr ferritic-martensitic steels. Advanced austenitic stainless steels (SS) like alloy 709 (20Cr-25Ni) are able to continue to form Cr-rich oxides at 650°C, while a conventional type 316 H SS formed a Fe-rich scale. The C diffusion profiles in SS specimens were quantified at 550°C–650°C using glow discharge optical emission spectroscopy and electron probe microanalysis. Analytical transmission electron microscopy was used to compare the thin protective Cr-rich oxide formed on alloy 709 in sCO 2 at 650°C to that formed in ambient air.

36 MATERIALS SCIENCE↗