Energy dispersive X-ray diffraction (EDXRD) for operando materials characterization within batteries
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99 GENERAL AND MISCELLANEOUS↗
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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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Characterization of wave energy resource and wave load conditions at Atlantic Marine Energy Center wave energy converter test sites
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Meuris, Brek Joseph↗
Reorganization Energies for Interfacial Proton-Coupled Electron Transfer to a Water Oxidation Catalyst
The reorganization energy (λ) for interfacial electron transfer (ET) and proton-coupled electron transfer (PCET) from a conductive metal oxide (In 2 O 3 :Sn, ITO) to a surface-bound water oxidation catalyst were extracted from kinetic data measured as a function of the thermodynamic driving force. Visible light excitation resulted in rapid excited-state injection (k inj > 10 8 s -1 ) to the ITO, which photo-initiated the two interfacial reactions of interest. The rate constants for both reactions increased with the driving force, −ΔG°, to a saturating limit, k max , with rate constants consistently larger for ET than for PCET. Marcus-Gerischer analysis of the kinetic data provided the reorganization energy for interfacial PCET (0.90 ± 0.02 eV) and ET (0.40 ± 0.02 eV), respectively. The magnitude of k max for PCET was found to decrease with pH, behavior that was absent for ET. Both the decrease in k max and the larger reorganization energy for an unwanted competing PCET reaction from the ITO to the oxidized catalyst showcases a significant kinetic advantage for driving solar water oxidation at high pH. Computational analysis revealed a larger inner-sphere reorganization energy contribution for PCET than for ET arising from a more significant change in the Ru–O bond length for PCET. Extending Marcus-Gerischer theory to PCET by including the excited electron-proton vibronic states and the proton donor-acceptor motion provided an apparent reorganization energy of 1.01 eV. Furthermore, this study demonstrates that the Marcus-Gerischer theory initially developed for ET can be reliably extended to PCET for quantifying and interpreting reorganization energies observed experimentally.
Catalysts Kinetic parameters↗
Quantum efficiency, photoemission energy spectra, and mean transverse energy of ultrananocrystalline diamond photocathode
The quantum efficiency and mean transverse energy of electrons emitted from a cathode determine the quality of beams generated from photoinjectors. The nitrogen-incorporated ultrananocrystalline diamond, (N)UNCD, is a new class of robust semiconductor photocathodes, which has been considered in photoinjectors for high peak current extraction. In this work, we measure the spectral response in quantum efficiency, photoemission energy spectra, and mean transverse energy of the (N)UNCD photocathode using a photoemission electron microscope. The observed quantum efficiency was comparable to that of copper photocathodes. Photoemission spectra showed the evidence of scattering of electrons before emission. This relaxation of electrons due to scattering is also observed in the spectral response of the mean transverse energy. The mean transverse energy is limited to ∼70 meV at the threshold. We attribute this to the physical and chemical roughness of the (N)UNCD photocathode and, hence, smoother films will be required to further reduce the mean transverse energy obtained from the (N)UNCD photocathode.
Kachwala, A. (ORCID:0000000301756478)↗
Band Energy Dependence of Defect Formation in the Topological Semimetal Cd3As2
Cadmium Arsenide (Cd3As2) is a prototypical Dirac semimetal that manifests topological properties in a 3D bulk material. In defect-free Cd3As2, the Fermi level lies at a minimum in the density of states at the Dirac point, but experimentally it forms with excess electron carriers and an elevated EF, thereby masking the topological features. To computationally study the self-doping of Cd3As2, we combine density functional theory (DFT) calculations for defect formation energies with quasi-particle self-consistent GW (QSGW) electronic structure calculations. We demonstrate an innate dependence of the point defect formation energies on carrier concentrations and use the QSGW calculated density of states to extrapolate formation energies to arbitrary electron concentrations. This approach allows the quantitative modeling of thermodynamic defect equilibria in topological semimetals and is used to predict how Cd3As2 growth conditions affect the position of EF relative to the Dirac point.
CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS↗
Differential Measurements of Jet Substructure and Partonic Energy Loss in Au+Au Collisions at √ sNN = 200 GeV
The STAR collaboration presents jet substructure measurements related to both the momentum fraction and the opening angle within jets in p+p and Au+Au collisions at √sNN =200GeV. The substructure observables include SoftDrop groomed momentum fraction (zg), groomed jet radius (Rg), and subjet momentum fraction (zSJ) and opening angle (θSJ). The latter observable is introduced for the first time. Fully corrected subjet measurements are presented for p+p collisions and are compared to leading-order Monte Carlo models. The subjet θSJ distributions reflect the jets leading opening angle and are utilized as a proxy for the resolution scale of the medium in Au+Au collisions. We compare data from Au+Au collisions to those from p+p which are embedded in minimum-bias Au+Au events in order to include the effects of detector smearing and the heavy-ion collision underlying event. The subjet observables are shown to be more robust to the background than zg and Rg. We observe no significant modifications of the subjet observables within the two highest-energy, back-to-back jets, resulting in a distribution of opening angles and the splittings that are vacuumlike. We also report measurements of the differential dijet momentum imbalance (AJ) for jets of varying θSJ. We find no qualitative differences in energy loss signatures for varying angular scales in the range 0.1< θSJ<0.3, leading to the possible interpretation that energy loss in this population of high-momentum dijet pairs, is due to soft medium-induced gluon radiation from a single color charge as it traverses the medium.
Abdallah, M. S.↗
Thermal modifications of mesons and energy-energy correlators from real-time simulations of a 𝑈(1) lattice gauge theory
We investigate thermal properties of a 𝑈(1) lattice gauge theory in 1 + 1 dimensions through real-time simulations. We extract the spectral functions directly coupling to the pseudoscalar and scalar mesons, demonstrating the thermal modifications of these states with increasing temperatures. Introducing the notion of energy-flow operators, we quantify the temporal buildup of correlations in the energy flows across the lattice. We demonstrate that energy-energy correlators fail to factorize to products of energy flows, both in the vacuum and at nonzero temperature, indicating the presence of nontrivial correlations in the quantum states. Our results constitute a first real-time ab initio study of bound-state thermal broadening and finite temperature energy-flow correlations in a gauge theory, providing a benchmark for future studies of hadronic matter under extreme conditions.
73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
Data-Driven Modeling and Optimization of Building Energy Consumption: a Case Study
Installing sensors and Building Automation Systems (BAS) allows controlling the facility operations while generating data that can be analyzed for model development. This work focuses on data-driven modeling of the building to optimize energy consumption. The City of Orlando aims to reduce its energy consumption so, they provided us access to their BAS for data and studying the operation of its facilities. We selected a mid-size pilot building to conduct data analysis and modeling. We develop an Application Programming Interface (API) to login to the servers and scrape data. The scraped data contains features ranging from environmental conditions to equipment activity. This dataset is a time series so, it's handled in accordance and analyzed to investigate patterns and relations between data points that help choose parameters for predictive models for building and equipment. Finally, the models are optimized to reduce the energy consumption of the facility.
Grover, Divas↗
Potential Heating Energy and Cost Savings of Dual Fuel Heat Pump Controls as a Residential Building Equipment Retrofit in the U.S.
This study investigated the energy and cost savings potential by modeling a dual fuel heat pump system with its control for a residential building in (5A) cold climate in U.S. The simulation analysis showed that the application of the DFHP system and its control to the target building can save the heating energy by 42% over a gas furnace system (baseline system). Although the HP-only system can save more heating energy (i.e., 53%) over the baseline system than DFHP system does, the DFHP with its control demonstrated the higher cost savings when a time of use electricity rate was considered.
Yoon, Yeobeom↗
Molecular Dynamics Free Energy Simulations Reveal the Mechanism for the Antiviral Resistance of the M66I HIV-1 Capsid Mutation
While drug resistance mutations can often be attributed to the loss of direct or solvent-mediated protein−ligand interactions in the drug-mutant complex, in this study we show that a resistance mutation for the picomolar HIV-1 capsid (CA)-targeting antiviral (GS-6207) is mainly due to the free energy cost of the drug-induced protein side chain reorganization in the mutant protein. Among several mutations, M66I causes the most suppression of the GS-6207 antiviral activity (up to ~84,000-fold), and only 83- and 68-fold reductions for PF74 and ZW-1261, respectively. To understand the molecular basis of this drug resistance, we conducted molecular dynamics free energy simulations to study the structures, energetics, and conformational free energy landscapes involved in the inhibitors binding at the interface of two CA monomers. To minimize the protein−ligand steric clash, the I66 side chain in the M66I−GS-6207 complex switches to a higher free energy conformation from the one adopted in the apo M66I. In contrast, the binding of GS-6207 to the wild-type CA does not lead to any significant M66 conformational change. Based on an analysis that decomposes the absolute binding free energy into contributions from two receptor conformational states, it appears that it is the free energy cost of side chain reorganization rather than the reduced protein−ligand interaction that is largely responsible for the drug resistance against GS-6207.
Sun, Qinfang (ORCID:0000000173621543)↗
USE OF NOVEL REFRACTORY DESIGN AND INSTALLATION TECHNIQUES FOR IMPROVED ENERGY EFFICIENCY IN IRON AND STEEL AND OTHER ENERGY INTENSIVE INDUSTRIES
This work describes a US Department of Energy funded program which unites key players to develop and deploy new technologies aimed at increasing energy efficiencies while reducing their overall energy and environmental footprint. The research brings together a vertically integrated collaborative team consisting of the end user (US Steel), material producers/suppliers (Allied Mineral Products and Reno Refractories), raw material suppliers (American Metallurgical Services, Minerals Manufacturing), and research organizations (Oak Ridge National Laboratory, National Energy Technology Laboratory and University of Alabama-Birmingham) with the objective of designing and producing new refractory materials. Design and production criteria are based on novel aggregates, improved particle packing, and engineered surface textures. In addition, the recycling and use of spent refractory materials has been investigated resulting in development of a novel installation technique that utilizes additive manufacturing technology and existing refractory shotcrete technology. The combination of these new technologies will improve the energy, environmental, and economic efficiencies of the steel industry while reducing the environmental footprint. The developed technology is potentially applicable to additional energy intensive industries including cement, glass, pulp and paper, and non-ferrous metals processing.
Hemrick, James↗
A techno-economic assessment framework for hydrogen energy storage toward multiple energy delivery pathways and grid services
Hydrogen energy storage (HES) transforms and stores electric energy from the grid into hydrogen, and supplements other energy storage and demand response resources in addressing challenges in renewable-intensive power systems. Understanding how to optimally utilize an HES system to maximize its economic benefits from stacked value streams is highly important to its development and deployment. Here, in this paper, we present a techno-economic assessment framework for an HES system considering three common energy delivery pathways and multiple grid and end-user services. Models are developed to capture the operational capability, flexibility, and constraints associated with hydrogen production, compression, storage, and utilization as well as different grid services in an economic assessment. To define the technically achievable benefits, an optimal dispatch formulation is proposed to maximize the economic benefits over a representative year with an hourly time step considering the trade-offs among different value streams. Representative case studies are designed and carried out to show how system configuration, energy delivery pathways, and grid services may affect economic benefits. It was found that value streams from bundling grid services account for up to 76% of the total benefits and are critical for an HES project to be financially viable.
25 ENERGY STORAGE↗
Real-time hybrid controls of energy storage and load shedding for integrated power and energy systems of ships
This paper presents an original energy management methodology to enhance the resilience of ship power systems. The integration of various energy storage systems (ESS), including battery energy storage systems (BESS) and super-capacitor energy storage systems (SCESS), in modern ship power systems poses challenges in designing an efficient energy management system (EMS). The EMS proposed in this paper aims to achieve multiple objectives. The primary objective is to minimize shed loads, while the secondary objective is to effectively manage different types of ESS. Considering the diverse ramp-rate characteristics of generators, SCESS, and BESS, the proposed EMS exploits these differences to determine an optimal long-term schedule for minimizing shed loads. Furthermore, the proposed EMS balances the state-of-charge (SoC) of ESS and prioritizes the SCESS’s SoC levels to ensure the efficient operation of BESS and SCESS. For better computational efficiency, we introduce the receding horizon optimization method, enabling real-time EMS implementation. Further, a comparison with the fixed horizon optimization (FHO) validates its effectiveness. Simulation studies and results demonstrate that the proposed EMS efficiently manages generators, BESS, and SCESS, ensuring system resilience under generation shortages. Additionally, the proposed methodology significantly reduces the computational burden compared to the FHO technique while maintaining acceptable resilience performance.
24 POWER TRANSMISSION AND DISTRIBUTION↗
Bridging the Energy Future: The Role and Potential of Hydrogen Co-Firing with Natural Gas
In the transition toward sustainable energy systems, the co-firing of hydrogen (H2) with natural gas emerges as a critical technology for cleaner power generation. This study examines its benefits, including emissions reduction, enhanced efficiency, and compatibility with existing infrastructure. Concurrently, it addresses the inherent challenges, such as combustion dynamics, necessary infrastructure modifications, and economic considerations. Incorporating global case studies, the review explores recent advancements in hydrogen production and co-firing, evaluating their practicality and operational efficiency. It also provides a critical examination of the economic implications and societal acceptance, which are crucial for the adoption of hydrogen technologies. Moreover, the review investigates the synergy between hydrogen and renewable energy technologies, assessing potential impacts on energy policy and regulation. Ultimately, this comprehensive analysis underscores the essential role of hydrogen co-firing in the energy sector and advocates for a comprehensive strategy that synergizes technological progress, economic viability, regulatory support, and public engagement to promote a resilient and sustainable energy future.
hydrogen co-firing↗
Corporate acceleration of the renewable energy transition and implications for electric grids
Not Available
O'Shaughnessy, Eric (ORCID:0000000169280184)↗
Modified Energy Span Analysis Reveals Heterogeneous Catalytic Kinetics
Mechanistic modeling is a cornerstone of catalyst development generally conducted with microkinetic models or density functional theory-based energy profiles. We extend the energy span model of homogeneous catalysis to heterogeneous systems by introducing the modified energy span analysis (MESA) model by implementing collision theory and gas-phase concentration effects. We determine analytically turnover frequencies, coverages, rate-determining steps, apparent activation energies, and reaction orders in agreement with microkinetic and kinetic Monte Carlo simulations. The model applies to discrete catalyst state systems, including single-atom catalysts, homogeneous systems, and microporous materials. A generalizable rate expression is derived for reactor modeling or mechanistic insights from solely experimentally measured reaction orders. Here, we illustrate MESA on three published mechanisms and reveal unexpected phenomena absent in traditional energy span profiles.
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
Considerations for Distributed Energy Resource Integration in Puerto Rico: DOE Multi-Lab Grid Modeling Support for Puerto Rico; Analytical Support for Interconnection and IEEE Std 1547-2018 National Renewable Energy Laboratory (Task 3.0)
To ensure the sustainable long-term recovery of Puerto Rico's electric power grid from hurricanes María and Irma and to build capacity to manage future potential natural disasters in the most secure and resilient way, the U.S. Department of Energy (DOE) convened experts from multiple national laboratories to develop a comprehensive set of data, models, analytic tools, and studies, considering inputs from a wide variety of stakeholder groups, to support technically sound recommendations for Puerto Rico's energy investment decisions. A resilient electric grid is vital to Puerto Rico's security, economy, and way of life, and it will provide the foundation for essential services that people and businesses on the island rely on every day. This report shows progress for a grid modeling task under the DOE-sponsored project that is a collaboration among the National Renewable Energy Laboratory (NREL) and other national laboratories. In Phase 1 of the multilab effort to support Puerto Rico's recovery, NREL provided the utility company Puerto Rico Electric Power Authority (PREPA) recommendations for a new framework of interconnection standards to accelerate the integration of utility-scale, transmission-connected renewable electrical generation and energy storage that ensure cross-technology compatibility and enable high deployment levels without compromising grid reliably, safety, or security. This Phase 2 report focuses on the interconnection of distributed energy resources (DERs) to the electric distribution system in Puerto Rico. This report is intended to familiarize the reader with Puerto Rico's distribution infrastructure and operational practices and procedures that are relevant to DER interconnection. The report also provides considerations for streamlining the interconnection process given the expected increase in deployments resulting from Puerto Rico's renewable portfolio standard (RPS) goal of 100% renewables by 2050. Accordingly, the report identifies considerations and concerns associated with the increase in intermittent generation, strategies for DER interconnection best practices, and the potential use of the latest technological solutions identified in the latest revision of the Institute of Electrical and Electronics Engineers (IEEE) 1547-2018 interconnection standard.
24 POWER TRANSMISSION AND DISTRIBUTION↗
Senior Housing Complex Energy Efficiency and Solar Energy Project
As part of a longer-term energy efficiency and solar development program on the Coeur d'Alene reservation, the Coeur d'Alene Tribe completed energy efficiency measures and deployed a solar photovoltaic system at its Senior Housing Complex. The project generated nearly 68,000 kWh of solar energy in its first year, and reduced energy used at the senior housing complex by 95,192 kWh, saving $7,144.56 in energy costs, and saving 48.1 metric tons of carbon dioxide.
14 SOLAR ENERGY↗