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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 OSTI2021

Giant terahertz polarization rotation in ultrathin films of aligned carbon nanotubes

For easy manipulation of polarization states of light for applications in communications, imaging, and information processing, an efficient mechanism is desired for rotating light polarization with a minimum interaction length. Here, we report giant polarization rotations for terahertz (THz) electromagnetic waves in ultrathin ( ∼ <#comment/> 45 n m ), high-density films of aligned carbon nanotubes. We observed polarization rotations of up to ∼ <#comment/> 20 ∘ <#comment/> and ∼ <#comment/> 110 ∘ <#comment/> for transmitted and reflected THz pulses, respectively. The amount of polarization rotation was a sensitive function of the angle between the incident THz polarization and the nanotube alignment direction, exhibiting a “magic” angle at which the total rotation through transmission and reflection becomes exactly 90°. Our model quantitatively explains these giant rotations as a result of extremely anisotropic optical constants, demonstrating that aligned carbon nanotubes promise ultrathin, broadband, and tunable THz polarization devices.

Baydin, Andrey (ORCID:0000000225673506)↗
DOE OSTI2022

Small Seismic Events in Oklahoma Detected and Located by Machine Learning–Based Models

A complete earthquake catalog is essential to understand earthquake nucleation and fault stress. Following the Gutenberg–Richter law, smaller, unseen seismic events dominate the earthquake catalog and are invaluable for revealing the fault state. The published earthquake catalogs, however, typically miss a significant number of small earthquakes. Part of the reason is due to a limitation of conventional algorithms, which can hardly extract small signals from background noise in a reliable and efficient way. To address this challenge, we utilized a machine learning method and developed new models to detect and locate seismic events. These models are efficient in processing a large amount of seismic data and extracting small seismic events. We applied our method to seismic data in Oklahoma, United States, and detected ~14 times more earthquakes compared with the standard Oklahoma Geological Survey catalog. The rich information contained in the new catalog helps better understand the induced earthquakes in Oklahoma.

58 GEOSCIENCES↗
DOE OSTI2013

U.S. Department of Energy Hydrogen Storage Cost Analysis

The overall objective of this project is to conduct cost analyses and estimate costs for on- and off-board hydrogen storage technologies under development by the U.S. Department of Energy (DOE) on a consistent, independent basis. This can help guide DOE and stakeholders toward the most-promising research, development and commercialization pathways for hydrogen-fueled vehicles. A specific focus of the project is to estimate hydrogen storage system cost in high-volume production scenarios relative to the DOE target that was in place when this cost analysis was initiated. This report and its results reflect work conducted by TIAX between 2004 and 2012, including recent refinements and updates. The report provides a system-level evaluation of costs and performance for four broad categories of on-board hydrogen storage: (1) reversible on-board metal hydrides (e.g., magnesium hydride, sodium alanate); (2) regenerable off-board chemical hydrogen storage materials(e.g., hydrolysis of sodium borohydride, ammonia borane); (3) high surface area sorbents (e.g., carbon-based materials); and 4) advanced physical storage (e.g., 700-bar compressed, cryo-compressed and liquid hydrogen). Additionally, the off-board efficiency and processing costs of several hydrogen storage systems were evaluated and reported, including: (1) liquid carrier, (2) sodium borohydride, (3) ammonia borane, and (4) magnesium hydride. TIAX applied a bottom-up costing methodology customized to analyze and quantify the processes used in the manufacture of hydrogen storage systems. This methodology, used in conjunction with ® software and other tools, developed costs for all major tank components, balance-of-tank, tank assembly, and system assembly. Based on this methodology, the figure below shows the projected on-board high-volume factory costs of the various analyzed hydrogen storage systems, as designed. Reductions in the key cost drivers may bring hydrogen storage system costs closer to this DOE target. In general, tank costs are the largest component of system cost, responsible for at least 30 percent of total system cost, in all but two of the 12 systems. Purchased BOP cost also drives system cost, accounting for 10 to 50 percent of total system cost across the various storage systems. Potential improvements in these cost drivers for all storage systems may come from new manufacturing processes and higher production volumes for BOP components. In addition, advances in the production of storage media may help drive down overall costs for the sodium alanate, SBH, LCH2, MOF, and AX-21 systems.

08 HYDROGEN↗
DOE OSTI2014

Optimization of Pressurized Oxy-Combustion with Flameless Reactor

Pressurized OxyECombustion is one of the most promising technologies for utility-scale power generation plants. Benefits include the ability to burn low rank coal and capture CO 2 . By increasing the flue gas pressure during this process, greater efficiencies are derived from increased quantity and quality of thermal energy recovery. UPA with modeling support from MIT and testing and data verification by Georgia Tech’s Research Center designed and built a 100 kW system capable of demonstrating pressurized oxyEcombustion using a flameless combustor. Wyoming PRB coal was run at 15 and 32 bar. Additional tests were not completed but sampled data demonstrated the viability of the technology over a broader range of operating pressures, Modeling results illustrated a flat efficiency curve over 20 bar, with optimum efficiency achieved at 29 bar. This resulted in a 33% (HHV) efficiency, a 5 points increase in efficiency versus atmospheric oxy-combustion, and a competitive cost of electricity plus greater CO 2 avoidance costs then prior study’s presented. UPA’s operation of the bench-scale system provided evidence that key performance targets were achieved: flue gas sampled at the combustor outlet had non-detectable residual fly ashes, and low levels of SO3 and heavy-metal. These results correspond to prior pressurized oxy-combustion testing completed by IteaEEnel.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2016

Flexible CdTe Solar Cells and Modules: Cooperative Research and Development Final Report, CRADA Number CRD-14-548

Lucintech and NREL will collaborate to develop flexible CdTe solar cells on flexible glass using sputtering and other deposition technologies. This initial work will be conducted under the DOE funded Foundational Program to Advance Cell Efficiency (FPACE) 1 project, and the interaction with Lucintech will focus on scaling up and transferring the high efficiency cell processes to module production on a pilot line.

14 SOLAR ENERGY↗
DOE OSTI2016

Feasibilities of a Coal-Biomass to Liquids Plant in Southern West Virginia

This project has generated comprehensive and realistic results of feasibilities for a coal-biomass to liquids (CBTL) plant in southern West Virginia; and evaluated the sensitivity of the analyses to various anticipated scenarios and parametric uncertainties. Specifically the project has addressed economic feasibility, technical feasibility, market feasibility, and financial feasibility. In the economic feasibility study, a multi-objective siting model was developed and was then used to identify and rank the suitable facility sites. Spatial models were also developed to assess the biomass and coal feedstock availabilities and economics. Environmental impact analysis was conducted mainly to assess life cycle analysis and greenhouse gas emission. Uncertainty and sensitivity analysis were also investigated in this study. Sensitivity analyses on required selling price (RSP) and greenhouse gas (GHG) emissions of CBTL fuels were conducted according to feedstock availability and price, biomass to coal mix ratio, conversion rate, internal rate of return (IRR), capital cost, operational and maintenance cost. The study of siting and capacity showed that feedstock mixed ratio limited the CBTL production. The price of coal had a more dominant effect on RSP than that of biomass. Different mix ratios in the feedstock and conversion rates led to RSP ranging from $104.3 - $157.9/bbl. LCA results indicated that GHG emissions ranged from 80.62 kg CO 2 eq to 101.46 kg CO2 eq/1,000 MJ of liquid fuel at various biomass to coal mix ratios and conversion rates if carbon capture and storage (CCS) was applied. Most of water and fossil energy were consumed in conversion process. Compared to petroleum-derived-liquid fuels, the reduction in GHG emissions could be between -2.7% and 16.2% with CBTL substitution. As for the technical study, three approaches of coal and biomass to liquids, direct, indirect and hybrid, were considered in the analysis. The process models including conceptual design, process modeling and process validation were developed and validated for different cases. Equipment design and capital costs were investigated on capital coast estimation and economical model validation. Material and energy balances and techno-economic analysis on base case were conducted for evaluation of projects. Also, sensitives studies of direct and indirect approaches were both used to evaluate the CBTL plant economic performance. In this study, techno-economic analysis were conducted in Aspen Process Economic Analyzer (APEA) environment for indirect, direct, and hybrid CBTL plants with CCS based on high fidelity process models developed in Aspen Plus and Excel. The process thermal efficiency ranges from 45% to 67%. The break-even oil price ranges from $86.1 to $100.6 per barrel for small scale (10000 bbl/day) CBTL plants and from $65.3 to $80.5 per barrel for large scale (50000 bbl/day) CBTL plants. Increasing biomass/coal ratio from 8/92 to 20/80 would increase the break-even oil price of indirect CBTL plant by $3/bbl and decrease the break-even oil price of direct CBTL plant by about $1/bbl. The order of carbon capture penalty is direct > indirect > hybrid. The order of capital investment is hybrid (with or without shale gas utilization) > direct (without shale gas utilization) > indirect > direct (with shale gas utilization). The order of thermal efficiency is direct > hybrid > indirect. The order of break-even oil price is hybrid (without shale gas utilization) > direct (without shale gas utilization) > hybrid (with shale gas utilization) > indirect > direct (with shale gas utilization).

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2017

Final Technical Report: Tandem and Bimetallic Catalysts for Oxidative Dehydrogenation of Light Hydrocarbon with Renewable Feedstock

An estimated 490 million metric tons of lignocellulosic biomass is available annually from U.S. agriculture and forestry. With continuing concerns over greenhouse gas emission, the development of efficient catalytic processes for conversion of biomass derived compounds is an important area of research. Since carbohydrates and polyols are rich in oxygen, approximately one oxygen atom per carbon, removal of hydroxyl groups via deoxygenation is needed. The necessary hydrogen required for hydrodeoxygenation (HDO) would either come from reforming biomass itself or from steam reforming of natural gas. Both processes contribute to global CO2 emission. The hope is that eventually renewable sources such as wind and solar for hydrogen production will become more viable and economic in the future. In the meantime, unconventional natural gas production in North America has boomed. As a result, light hydrocarbons present an opportunity when coupled with biomass derived oxygenates to generate valuable products from both streams without co-production of carbon dioxide. This concept is the focus of our current funding period. The objective of the project requires coupling two different types of catalysis, HDO and dehydrogenation. Our hypothesis was formulated around our success in establishing oxorhenium catalysts for polyol HDO reactions and known literature precedence for the use of iridium hydrides in alkane dehydrogenation. To examine our hypothesis we set out to investigate the reaction chemistry of binuclear complexes of oxorhenium and iridium hydride.

09 BIOMASS FUELS↗
DOE OSTI2016

Towards a method of rapid extraction of strontium-90 from urine: urine pretreatment and alkali metal removal

A technical program to support the Centers of Disease Control and Prevention is being developed to provide an analytical method for rapid extraction of Sr-90 from urine, with the intent of assessing the general population’s exposure during an emergency response to a radiological terrorist event. Results are presented on the progress in urine sample preparation and chemical separation steps that provide an accurate and quantitative detection of Sr-90 based upon an automated column separation sequence and a liquid scintillation assay. Batch extractions were used to evaluate the urine pretreatment and the column separation efficiency and loading capacity based upon commercial, extractant-loaded resins. An efficient pretreatment process for decolorizing and removing organics from urine without measurable loss of radiostrontium from the sample was demonstrated. In addition, the Diphonix® resin shows promise for the removal of high concentrations of common strontium interferents in urine as a first separation step for Sr-90 analysis.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2012

Nanostructured Materials for High Efficiency Low Cost Solution-Processed Photovoltaics

The goal of the project was to develop a suite of materials coupled with processing technologies aimed at the fabrication of entirely solution-processed photovoltaic devices. Most of the emphasis in terms of innovation was placed on the transparent electrodes, widely considered a critical component of the solar cell in terms of cost and performance. The active layer technologies proposed hinged on the fabrication and deposition of semiconducting nanoparticles. The electrode development hit all the milestones proposed: by the end of the grant we were able to fabricate transparent and flexible electrodes with transmission over the solar spectrum higher than 85% and sheet resistance lower than 10 Ω/square. To the best of our knowledge, this is the highest-performance transparent electrode reported. Furthermore these electrodes were deposited by spray-coating, a large-area, low-cost deposition techniques. Hence the first main goal of the proposal, which was to find an alternative to ITO was successfully achieved. Organic photovoltaic devices were made with these electrodes having a performance indistinguishable from that of devices made on ITO (the industry standard), e.g. ~5% for P3HT:PCBM cells. We also innovated in the active-area part of the device where semiconducting inks were designed rather than nanoparticle suspensions. The process we selected, called air-stable ink rolling (AIR) allowed to deposit well-controlled films of ternary and quaternary II-VI semiconductors. Developing a new technology from scratch proved to be more challenging than anticipated and therefore we were not able to demonstrate a fully integrated device using our nanostructured high-performance transparent electrodes as well as AIR active layers. As a result, we did not achieve the second main goal of the proposal, which was to fabricate an entire cell using nanostructured materials. We were able to develop the components separately but did not integrate them in a device.

14 SOLAR ENERGY↗
DOE OSTI2017

Development and Experimental Benchmark of Simulations to Predict Used Nuclear Fuel Cladding Temperatures during Drying and Transfer Operations

Radial hydride formation in high-burnup used fuel cladding has the potential to radically reduce its ductility and suitability for long-term storage and eventual transport. To avoid this formation, the maximum post-reactor temperature must remain sufficiently low to limit the cladding hoop stress, and so that hydrogen from the existing circumferential hydrides will not dissolve and become available to re-precipitate into radial hydrides under the slow cooling conditions during drying, transfer and early dry-cask storage. The objective of this research is to develop and experimentallybenchmark computational fluid dynamics simulations of heat transfer in post-pool-storage drying operations, when high-burnup fuel cladding is likely to experience its highest temperature. These benchmarked tools can play a key role in evaluating dry cask storage systems for extended storage of high-burnup fuels and post-storage transportation, including fuel retrievability. The benchmarked tools will be used to aid the design of efficient drying processes, as well as estimate variations of surface temperatures as a means of inferring helium integrity inside the canister or cask. This work will be conducted effectively because the principal investigator has experience developing these types of simulations, and has constructed a test facility that can be used to benchmark them.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2017

Brentwood Lessons Learned Project Report

The purpose of this report is to document lessons learned in the installation of the hydrogen fueling station at the National Park Service Brentwood site in Washington, D.C., to help further the deployment of hydrogen infrastructure required to support hydrogen and other fuel cell technologies. Hydrogen fueling is the most difficult infrastructure component to build and permit. Hydrogen fueling can include augmenting hydrogen fueling capability to existing conventional fuel fueling stations as well as building brand new hydrogen fueling stations. This report was produced as part of the Brentwood Lessons Learned project. The project consisted of transplanting an existing modular hydrogen fueling station from Connecticut to the National Park Service Brentwood site. This relocation required design and construction at the Brentwood site to accommodate the existing station design as well as installation and validation of the updated station. One of the most important lessons learned was that simply moving an existing modular station to an operating site was not necessarily straight-forward - performing the relocation required significant effort and cost. The station has to function at the selected operating site and this functionality requires a power supply, building supports connecting to an existing alarm system, electrical grounding and lighting, providing nitrogen for purging, and providing deionized water if an electrolyzer is part of the station package. Most importantly, the station has to fit into the existing site both spatially and operationally and not disrupt existing operations at the site. All of this coordination and integration requires logistical planning and project management. The idea that a hydrogen fueling station can be simply dropped onto a site and made immediately operational is generally not realistic. Other important lessons learned include that delineating the boundaries of the multiple jurisdictions that have authority over a project for all parties involved in the project are key to an efficient approval process; and site investigation is necessary when integrating a new station design onto an existing site, particularly an older existing site that may have limited documentation on the site history and operations. The lessons learned for permitting and subcontracting construction work can be applied to other similar sites and to commercial sites.

30 DIRECT ENERGY CONVERSION↗
DOE OSTI2017

Design of Stratified Functional Nanoporous Materials for CO 2 Capture and Conversion

The objective of this project is to develop novel nanoporous materials for CO 2 capture and conversion. The motivation of this work is that capture of CO 2 from flue gas or the atmosphere coupled with catalytic hydrogenation of CO 2 into valuable chemicals and fuels can reduce the net amount of CO 2 in the atmosphere while providing liquid transportation fuels and other commodity chemicals. One approach to increasing the economic viability of carbon capture and conversion is to design a single material that can be used for both the capture and catalytic conversion of CO 2 , because such a material could increase efficiency through process intensification. We have used density functional theory (DFT) methods to design catalytic moieties that can be incorporated into various metal organic framework (MOF) materials. We chose to work with MOFs because they are highly tailorable, can be functionalized, and have been shown to selectively adsorb CO 2 over N 2 , which is a requirement for CO 2 capture from flue gas. Moreover, the incorporation of molecular catalytic moieties into MOF, through covalent bonding, produces a heterogeneous catalytic material having activities and selectivities close to those of homogeneous catalysts, but without the draw-backs associated with homogeneous catalysis.

36 MATERIALS SCIENCE↗
DOE OSTI2018

A Critical Literature Review of Defrost Technologies for Heat Pumps and Refrigeration Systems

When the operating conditions are extremely cold and humid and the surface temperature of the heat exchanger well below the freezing point (lower than the dew point temperature of the air) moisture from the air stream will freeze on the surface after condensation and the frost will start growing. The frost growth degrades the performance of the system considerably. It hinders the airflow and increases the pressure drop through the coil which means more fan power is requires for to maintain the desired flow rate. With reduced flow rate due to the increase of pressure drop, system’s capacity drops rapidly. In the case of heat pump the capacity of the evaporator decreases due to the airflow drop, which reduces the overall heating capacity and coefficient of performance of the heat pump. Additionally, the frost layer increases the thermal resistance to the heat transfer between the air and refrigerant. The reduction in airflow and increased thermal resistance reduces the heat energy extracted by the evaporator and decreases the heat pump capacity and efficiency. Similar process is observed for the cooling coils of commercial refrigeration system where the frost growth can dramatically reduce the system capacity. Once the performance reaches its minimum acceptable stage, a defrost process is introduced to remove the frost layer and to achieve the performance at the start of the cycle. The frost defrost process is repeated continuously. Overall the frost growth is highly undesired phenomena which can cause considerable reduction in performance of the system.

42 ENGINEERING↗
DOE OSTI2018

A Novel High Efficiency 1.5 MW, 110 GHz Gyrotron with HE11 Output for Plasma Heating

We applied a recently developed mode converter synthesis method (D. Sobolev and G. Denisov, “Principles of Synthesis of Multimode Waveguide Units”, IEEE Trans. Plasma Sci., Vol. 38, No. 10, Oct. 2010) to the design of a quasi-optical (QO) launcher for high power gyrotrons. This technique, based on the reciprocity theorem, provides a highly efficient iterative process. The initial design results of a QO launcher obtained using the Launcher Optimization Tool (LOT) were used as input to the new launcher surface synthesis algorithm. The target radiation field was defined as a Gaussian beam with best fit waist size to beam radiated from LOT optimized surface. A significant improvement in the quality of launcher output beam was obtained and the Gaussian output content was calculated at 98%.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2020

MSR Fuel Salt Qualification Methodology

This report documents the continuing activities at Oak Ridge National Laboratory (ORNL) in support of the US Nuclear Regulatory Commission (NRC) efforts to develop an efficient, appropriate process for liquid fuel salt system qualification. Fuel qualification for salt-cooled molten salt reactors (MSRs) is part of the ongoing coated particle fuel qualification effort. Fuel qualification is a process which provides high confidence that physical and chemical behavior of fuel is sufficiently understood so that it can be adequately modeled for both normal and accident conditions, reflecting the role of the fuel design in the overall safety of the facility. Uncertainties are defined so that calculated fission product releases include the appropriate margins to ensure conservative calculation of radiological dose consequences. The initial phase of ORNL’s activities is documented in ORNL/LTR-2018/1045 Molten Salt Reactor Fuel Qualification Considerations and Challenges.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2021

Gamma Spectroscopy Detector Candidates and Radioisotope Identification Algorithms for Use in National Security Applications

In 2006, the United States Congress mandated for the Department of Homeland Security (DHS) to screen all cargo containers to protect against terrorist acts and ensure the safety and security of the nation. Containers are screened by gamma and neutron detectors to ensure threat material is not smuggled into the country. However, because commerce is radioactive, detecting the presence of radioactive materials is not sufficient in ensuring the safety and security of the nation. Radioactive materials must also be identified in real time, thus distinguishing threat sources (Uranium-235 and Plutonium-230) from non-threat sources (kitty litter, pot ash, medical isotopes). Screening cargo containers can be considered a two-step process (1) alerting to the presence of radioactive material when gamma counts exceed a threshold setting, and (2) once alerted, identifying the type of radioactive material, which is done by collecting a gamma spectra and analyzing it with an analysis tool/algorithm. For this reason, it is important to evaluate not only emerging technology in neutron and gamma detection, but also investigate new advances in algorithm development for radioisotope identification (RIID). New candidates in detection and on-board algorithm analysis might offer opportunities to make the scanning, detection, and identification process more efficient while still ensuring the health and safety of the public. This research will investigate emerging technology in radiation detection focused on gamma spectroscopy capabilities and RIID algorithms for DHS applications.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2022

Oppenheimer Science and Energy Leadership Program (OSELP) Software and Computing Strategy for the Future of Weapons Physics Applications [Slides]

Mission drivers at the national level are evolving to accommodate a broadening landscape. The U.S. faces a rapidly evolving, threat-based environment with an associated expansion of national-level priorities. Priorities continue to include all aspects of sustaining the existing, aging stockpile. Now, however, we must also include consideration of options for a future deterrent, including efficacy of the deterrent against new threats (threat assessment and response), capability needs associated with new materials and modern manufacturing and production processes, and efficiency requirements for a modern workflow for weapons design. Executing this complex strategy will come with challenges. We must execute our current mission, while we prepare for future missions and an increasingly uncertain future.

42 ENGINEERING↗
DOE OSTI2022

Mapping the Opportunity Space to Model the Circular Economy Using Tools Funded by the DOE Office of Energy Efficiency and Renewable Energy

An increasing rate of material consumption and a growing population mean that the Earth's supply of natural resources is witnessing an unsustainable and unprecedented demand. This forces us to find solutions that ensure the availability of resources for sustenance of our society in the years to come. Actors from various backgrounds are addressing these challenges from their own perspectives: engineers are developing efficient manufacturing processes, designers are creating lightweight and durable products, educators are incorporating sustainable thinking in their curricula, policymakers are finding interdisciplinary solutions that benefit society at large, etc. Circular economy (CE) is one such approach to resource use that aims to move away from the linear material use framework of "take-make-waste" to a more circular and interdependent system where product, material and resource use is maximized to avoid unnecessary social, economic, and environmental costs. The purpose of this report is to explain how to approach evaluating the circular economy and to help researchers identify existing tools that can be used or that can serve as starting points for their research needs.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗