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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 253 records · Page 14
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Accelerated CO2 Storage Optimization Using Multi-Resolution Fourier Neural Operator at the Illinois Basin Decatur Project (IBDP)

This paper presents a deep learning-based approach for optimizing CO2 injection in carbon capture and storage (CCS) operations. We developed a multi-resolution machine learning model to significantly reduce data generation costs. Utilizing this proxy model, we implemented a multi-objective genetic algorithm to optimize well control during the CO2 injection process. The proposed approach was applied to the Illinois Basin Decatur Project (IBDP), successfully optimizing the CO2 injection schedule based on three key objectives: maximizing the amount of CO2 stored, maximizing sweep efficiency, and minimizing pressure increase. The use of the proxy model accelerated the optimization workflow by two orders of magnitude, while the cost of data generation for the proxy model was reduced by 90% by utilizing a coarse-scale model.

accelerated CO2 storage optimization↗
DOE OSTI2022

Site demonstration and performance evaluation of MPC for a large chiller plant with TES for renewable energy integration and grid decarbonization

Thermal energy storage (TES) for a cooling plant is a crucial resource for load flexibility. Traditionally, simple, heuristic control approaches, such as the storage priority control which charges TES during the nighttime and discharges during the daytime, have been widely used in practice, and shown reasonable performance in the past benefiting both the grid and the end-users such as buildings and district energy systems. However, the increasing penetration of renewables changes the situation, exposing the grid to a growing duck curve, which encourages the consumption of more energy in the daytime, and volatile renewable generation which requires dynamic planning. The growing pressure of diminishing greenhouse gas emissions also increases the complexity of cooling TES plant operations as different control strategies may apply to optimize operations for energy cost or carbon emissions. This paper presents a model predictive control (MPC), site demonstration and evaluation results of optimal operation of a chiller plant, TES and behind-meter photovoltaics for a campus-level district cooling system. The MPC was formulated as a mixed-integer linear program for better numerical and control properties. Compared with baseline rule-based controls, the MPC results show reductions of the excess PV power by around 25%, of the greenhouse gas emission by 10%, and of peak electricity demand by 10%.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2020

Structural and Electrochemical Impacts of Mg/Mn Dual Dopants on the LiNiO 2 Cathode in Li-Metal Batteries

Doping chemistry has been regarded as an efficient strategy to overcome some fundamental challenges facing the “no-cobalt” LiNiO 2 cathode materials. By utilizing the doping chemistry, we evaluate the battery performance and structural/chemical reversibility of a new no-cobalt cathode material (Mg/Mn-LiNiO 2 ). The unique dual dopants drive Mg and Mn to occupy the Li site and Ni site, respectively. We report the Mg/Mn-LiNiO 2 cathode delivers smooth voltage profiles, enhanced structural stability, elevated self-discharge resistance, and inhibited nickel dissolution. As a result, the Mg/Mn-LiNiO 2 cathode enables improved cycling stability in lithium metal batteries with the conventional carbonate electrolyte: 80% capacity retention after 350 cycles at C /3, and 67% capacity retention after 500 cycles at 2 C (22 °C). We then take the Mg/Mn-LiNiO 2 as the platform to investigate the local structural and chemical reversibility, where we identify that the irreversibility takes place starting from the very first cycle. The highly reactive surface induces the surface oxygen loss, metal reduction reaching the subsurface, and metal dissolution. Our data demonstrate that the dual dopants can, to some degree, mitigate the irreversibility and improve the cycling stability of LiNiO 2 , but more efforts are needed to eliminate the key challenges of these materials for battery operation in the conventional carbonate electrolyte.

25 ENERGY STORAGE↗
DOE OSTI2025

Studying the Durability of Molybdenum Carbide Aerogel as an Electrocatalyst Support for Proton Exchange Membrane Fuel Cells

Carbon-supported platinum nanoparticles (Pt/C) are currently the state-of-the-art catalyst in proton exchange membrane fuel cells (PEMFCs). Unfortunately, the carbon support lacks the ability to stabilize the metal catalyst, as platinum tends to dissolve and agglomerate, significantly compromising the durability. Herein, we synthesized a ceramic material, molybdenum carbide aerogel (MCAG), and utilized it as a Pt support for PEMFCs, as an alternative for conventional carbon supports. N 2 adsorption and XRD analysis showed that the MCAG possesses a combination of high porosity and a well-defined ceramic crystalline structure. The Pt/MCAG system was studied for its electrocatalytic activity toward ORR in a half-cell and demonstrated satisfactory reaction kinetics and electrochemical active surface area, comparable to the commercial Pt/C. For durability examination, an accelerated stress test (AST) in a single cell was conducted with the Pt/MCAG catalyst at the cathode, following the U.S. DOE electrocatalyst AST protocol. Intermediate polarization curves and cyclic voltammograms were recorded over the course of the AST to monitor the aging process. The results indicated that the MCAG support exhibited superior durability in long-term fuel cell operation compared to a carbon support. The Pt/MCAG system demonstrated stable behavior during the progressive stages of the AST, retaining more than 50% of its initial performance by the end of the test, whereas carbon-supported Pt preserved only 30%.

25 ENERGY STORAGE↗
DOE OSTI2022

Energy-efficient building technologies

Buildings consume one-third of the total final energy produced on the globe and are responsible for almost 40 percent of total carbon dioxide generation annually. The latest carbon dioxide burden of buildings approached 10 Gigatons in the year 2019. Energy-efficient building technologies are necessary to address the climate change induced by greenhouse gases and fulfill the growth in demand and continuously depleting energy reserves. To meet the net-zero carbon footprint goals, sustainable, renewable energy resources, efficient building technologies, and demand management strategies are needed. Achieving zero emissions will require buildings to be equipped with energy-efficient technologies while completely avoiding on-site fossil fuel consumption and being only powered by renewable energy. In this context, this chapter provides an overview of various building technologies, including envelopes, materials, equipment, appliances, and integration concepts, which will play a significant role in lowering the overall energy consumption in both existing building stock and new buildings. Specifically, the following areas are discussed in detail: emerging building envelope designs, thermal comfort and refrigeration equipment, bridging technologies for improved energy efficiency in the ongoing energy transition, hybrid renewable (photovoltaic) configurations, energy storage technologies, miscellaneous appliances, refrigerants, and renewable fuels. The influence of key design and operating characteristics on annual carbon footprint is presented.

Cheekatamarla, Praveen↗
DOE OSTI2022

Multiscale simulation of integrated energy system and electricity market interactions

Accelerating the deep decarbonization of the world's electric grids requires the coordination of complex energy systems and infrastructures across timescales from seconds to decades. Here, we present a new multiscale simulation framework that integrates process- and grid-centric modeling paradigms to better design, operate, and control integrated energy systems (IESs), which combine multiple technologies, in wholesale energy markets. Traditionally, IESs are analyzed with a process-centric paradigm such as levelized cost of electricity (LCOE) or annualized net revenue, ignoring important interactions with electricity markets. This framework explicitly models the complex interactions between an IES's bidding, scheduling, and control decisions and the energy market's clearing and settlement processes, while incorporating operational uncertainties. Through two case studies, we show the importance of understanding and quantifying complex resource-grid interactions. In case study 1, we demonstrate that optimized bidding from one resource shifts the profit distribution for all energy systems in the market. This result suggests new and more flexible IES technologies can disrupt the economics of all market participants, possibly leading to accelerated retirements of less flexible resources. Interestingly, the optimized bidding has little impact on grid-level aggregate statistics, such as total generation costs and renewable penetration rate. While aggregate modeling strategies may remain valid under some IES adoption scenarios for analysis focused on regional outcomes, direct comparisons of IES technologies at specific locations without considering these interactions may lead to misleading or incorrect conclusions. In case study 2, we consider the design and flexible operation of IESs that hybridize conventional generators with energy storage. Through a sensitivity analysis, we find that as the size of the storage system increases, the total number of start-ups for coal- and natural gas-based IESs reduced by 25% and 33.6%, and the total thermal generator ramping (i.e., mileage) reduced by 86.5% and 62.5%, respectively. This shows the primary benefit of storage may not be reduced operational costs (which do not change significantly) but fewer start-ups and less ramping, which may greatly simplify the design, operation, and control of carbon capture systems. The new modeling and optimization capabilities from this work enable the coupling of rigorous, dynamic process models with grid-level production cost models to quantitatively identify the nuanced interdependencies across these vast timescales that must be addressed to realize clean, safe, and secure energy production. Moreover, the proposed general multiscale simulation framework is applicable to all IES technologies and can be easily extended to consider other energy carriers (e.g., hydrogen, ammonia) and energy infrastructures (e.g., natural gas pipelines).

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2025

Hybrid Energy-Powered Electrochemical Direct Ocean Capture Model

Offshore synthetic fuel production and marine carbon dioxide removal can be enabled by direct ocean capture, which extracts carbon dioxide from the ocean that then can be used as a feedstock for fuel production or sequestered underground. To maximize carbon capture, plants require a variety of low-carbon energy sources to operate, such as variable renewable energy. However, the impacts of variable power on direct ocean capture have not yet been thoroughly investigated. To facilitate future deployments, a generalizable model for electrodialysis-based direct ocean capture plants is created to evaluate plant performance and electricity costs under intermittent power availability. This open-source Python-based model captures key aspects of the electrochemistry, ocean chemistry, post-processing, and operation scenarios under various conditions. To incorporate realistic energy supply dynamics and cost estimates, the model is coupled with the National Renewable Energy Laboratory’s H2Integrate tool, which simulates hybrid energy system performance profiles and costs. This integrated framework is designed to provide system-level insights while maintaining computational efficiency and flexibility for scenario exploration. Initial evaluations show similar results to those predicted by the industry, and demonstrate how a given plant could function with variable power in different deployment locations, such as with wind energy off the coast of Texas and with wind and wave energy off the coast of Oregon. The results suggest that electrochemical systems with greater tolerances for power variability and low minimum power requirements may offer operational advantages in variable-energy contexts. However, further research is needed to quantify these benefits and evaluate their implications across different deployment scenarios.

16 TIDAL AND WAVE POWER↗
DOE OSTI2022

Feedstock and Catalyst Impact on Bio-Oil Production and FCC Co-Processing to Fuels

NREL's thermochemical biomass conversion research is focused on ex-situ upgrading of biomass fast-pyrolysis (FP) vapors as an efficient route to completely biogenic pyrolysis-based fuel precursors, fuels, and value-added chemicals depending on catalyst and process conditions. A near term pathway being developed uses these liquids for co-processing with petroleum feedstocks to assess biogenic carbon incorporation in hydrocarbon fuel feedstocks for potential refinery use. In this work, the impact of feedstock and catalyst on catalytic fast pyrolysis oil (CFPO) composition was determined with the oils then assessed for biogenic fuel production via FCC (fluidized catalytic cracking) co-processing. Biomass vapors were generated via fast pyrolysis with destabilizing vapor components (char, inorganics, tar aerosols) removed by hot gas filtration to produce clean vapors more responsive to catalytic upgrading. A Davison Circulating Riser (DCR), a petroleum industry standard for fluidized catalytic cracking (FCC) catalyst evaluation, was coupled to a custom pyrolyzer system designed to produce consistent-composition pyrolysis vapors as feed to the DCR. Pyrolysis vapors, derived from pure hardwood and softwood, were upgraded using commercially available modified zeolite-based catalysts to produce CFPOs. These upgraded oils were analyzed via 31P and 13C NMR spectroscopy, GCxGC-TOF/MS, carbonyl and ultimate analysis (CHNO), and simulated distillation (SIMDIS) to assess both oil chemistry and distillation behavior as they relate to catalyst and feedstock type for producing fungible hydrocarbon product liquids. These exploratory vapor-phase-upgrading results demonstrated the feasibility of producing refinery-compatible hydrocarbon fuel intermediates entirely from biomass-derived fast-pyrolysis vapors using an industry-accepted DCR system for catalytic upgrading. The FCC co-processing results demonstrated the feasibility of using CFPOs with VGO feeds in FCC refinery operations to produce biogenic carbon containing fuels.

biogenic carbon↗
DOE OSTI2022

Co-intercalation-free ether electrolytes for graphitic anodes in lithium-ion batteries

Carbonate-based electrolytes are widely used in Li-ion batteries but are limited by a small operating temperature window and poor cycling with silicon-containing graphitic anodes. The lack of non-carbonate electrolyte alternatives such as ether-based electrolytes is due to undesired solvent co-intercalation that occurs with graphitic anodes. Here, we show that fluoroethers are the first class of ether solvents to intrinsically support reversible lithium-ion intercalation into graphite without solvent co-intercalation at conventional salt concentrations. In full cells using a graphite anode, they enable 10-fold higher energy densities compared to conventional ethers, and better thermal stability over carbonate electrolytes (operation up to 60 °C) by producing a robust solvent-derived solid electrolyte interphase (SEI). As single-solvent–single-salt electrolytes, they remarkably outperform carbonate electrolytes with fluoroethylene carbonate (FEC) and vinylene carbonate (VC) additives when cycled with graphite–silicon composite anodes. In conclusion, our molecular design strategy opens a new class of electrolytes that can enable next generation Li-ion batteries with higher energy density and a wider working temperature window.

25 ENERGY STORAGE↗
DOE OSTI2022

Quench and Partitioning Steels

Quench and Partitioning (Q&P) steels are produced by implementing a unique thermal history designed to produce microstructures that contain martensite, and potentially ferrite, along with significant amounts of retained austenite stabilized by high carbon contents. Carbon-stabilized austenite is obtained by carbon transfer from martensite into austenite after a controlled amount of martensite is introduced by judicious selection of a so-called quench temperature at which quenching below the martensite start temperature is interrupted. Following the quench interruption, during the partitioning step, the steel is either held at the quench temperature or brought to a higher temperature and held for a specific time, to stimulate carbon transfer from martensite to austenite, to decrease the carbon supersaturation in martensite and correspondingly stabilize the austenite by carbon enrichment. A final quench to room temperature may be associated with the transformation of a certain fraction of austenite into secondary or “fresh” martensite, which is usually undesirable. A review of the Q&P process is presented, including prediction of austenite retention, alloying effects on its stabilization, a mechanical properties survey, including tensile and local formability relevant to sheet steels for automotive applications, along with perspectives on reactions competing with carbon partitioning that may operate during partitioning.

Kang, Singon↗
DOE OSTI2026

Advancing technologies for lignin-based jet fuel production in aqueous phase

Integrating lignin into a cellulosic ethanol plant for the co-production of lignin-based jet fuel (LJF) in aqueous phase offers a significant opportunity to boost operational efficiency, economic viability, carbon conversion, and the overall sustainability of biofuel and chemical production. LJF is lignin-structure-based jet fuel blendstocks primarily composed of alkyl-substituted mono-, bi-, and tri-cyclohexanes. It exhibits high energy density, potential for low emissions, and favourable blend characteristics that comply with drop-in specifications. An overview of lignin feedstock, catalytic processes, LJF chemical compositions, fuel properties tests, and techno-economic analysis (TEA) and life cycle assessment (LCA) indicate that (1) the reactivity of lignin plays a crucial role in its structure transformation to LJF molecules; (2) catalytic processing of lignin to LJF can occur through a simultaneous depolymerization and hydrodeoxygenation process, bypassing the intermediate step of producing and upgrading lignin-derived oil; (3) LJF's uniqueness molecules making it more promising for high energy content and low emission jet fuel properties for next generation sustainable aviation fuel (SAF); and (4) TEA and LCA demonstrate that LJF is not only potentially cost-effective but also offers favourable carbon footprint compared to other SAFs. In conclusion, this review highlights the most recent advancements in LJF technology, along with the challenges and opportunities that lie ahead in fulfilling its potential.

09 BIOMASS FUELS↗
DOE OSTI2024

Advancing spatiotemporal forecasts of CO 2 plume migration using deep learning networks with transfer learning and interpretation analysis

Accurate and timely forecasts of CO 2 plume distribution throughout the injection and post-injection phases are crucial for detecting plume migration, assessing leakage risks, and supporting operational decisions in geologic carbon storage (GCS). Current convolutional neural network-based approaches primarily focus on spatial information and overlook temporal dependencies in plume distributions, thus limiting their ability to capture dynamic movement effects and provide accurate predictions of plume migration. In this work, we propose two deep learning models, Auto-Encoder (AE)-LSTM and Encoder-Decoder (ED)-ConvLSTM, each uniquely designed to capture both spatial and temporal features. We apply the proposed methods to forecast the dynamic distribution of CO 2 plumes based on 108 reservoir simulations over a 30-year injection and a 30-year post-injection period. The results indicate that the ED-ConvLSTM model outperforms the AE-LSTM model in accurately predicting the spatiotemporal dynamics of CO 2 plume migration, achieving R 2 values above 0.99. To provide a deeper understanding of these model predictions, we employ a gradient-based explanation method on the trained models. This approach provides insights into the influence of input variables on plume migration forecasts and uncovers the underlying prediction mechanisms of the proposed models. Furthermore, we introduce a transfer learning technique, enabling fast and accurate plume migration forecasting in the post-injection phase by leveraging the trained model during the injection phase. This reduces the necessity for extensive data collection or re-training. In conclusion, the methods proposed in our work enhances the performance and interpretability of CO 2 plume migration forecasts, thereby facilitating informed decision-making throughout the entire lifecycle of GCS applications.

58 GEOSCIENCES↗
DOE OSTI2024

Impact of cement composition, brine concentration, diffusion rate, reaction rate and boundary condition on self-sealing predictions for cement-CO 2 systems

Geological CO 2 storage (GCS) plays an important role in curbing CO 2 emissions by reducing the carbon footprint of difficult to decarbonize operations and achieve negative CO 2 emissions through activities like Bioenergy with Carbon Capture and Storage (BECCS) and Direct Air Carbon Capture and Storage (DACCS). Leakage of CO 2 through wells is an important concern when it comes to deployment of large-scale GCS. Existing wells in sites that are otherwise suitable for GCS can act as conduits for stored CO 2 to escape the reservoir. There is broad consensus that the main risk of leakage through wellbores is via fractures/damaged pathways. The results from several studies evaluating the permeability evolution of cement fractures in wells upon leakage of CO 2 agree that smaller fracture apertures, slower brine velocities and higher brine residence times promote self-sealing of fractures by mineral precipitation. Quantitatively, however, the differences in sealing conditions are significant and are typically attributed to differences in experimental conditions or model assumptions. Here we examine the sensitivity of our model, describing CO 2 leakage through wellbores, to cement composition, brine concentration, diffusion rates, and reaction rates. We also evaluate the impact of the boundary condition to allow comparisons between observations from experiments performed at constant flow rate and model predictions made at constant pressure conditions. Our results show that diffusion and reactions rates have the most impact on the self-sealing criteria for cement-CO 2 systems. In addition, conditions associated with self-sealing of fractures at constant flow rate require longer fractures, smaller fracture apertures, and slower velocities than under constant pressure.

58 GEOSCIENCES↗
DOE OSTI2023

Voltage and Temperature Limits of Advanced Electrolytes for Lithium-Metal Batteries

Several advanced electrolytes (mainly ether-based) have recently demonstrated excellent electrochemical performance in high energy density lithium (Li)-metal batteries. However, the safety of these ether-based electrolytes is still unknown. This work evaluates the thermal stability of these new formulations to understand their safety limits of operation in comparison to carbonate electrolytes typically used in Li-ion batteries. Electrolyte stability is assessed in conjunction with LiNi 0.8 Mn 0.1 Co 0.1 O 2 cathode and Li-metal anode at ultra-high voltages (≤ 4.8 V) and temperatures (≤ 300°C) to trigger thermal runaway, where onset and extent of heat release are monitored via isothermal microcalorimetry and differential scanning calorimetry Most ether-based electrolytes show improved thermal resilience over commercial carbonate formulations when heated up to 300°C. The thermal behavior in presence of charged cathode and Li-metal suggests that the new electrolytes may be better at stabilizing active material surfaces than carbonate electrolytes. Although extreme voltages severely destabilize the ether-based formulations, prompting thermal runaway, a phosphate based localized high concentration electrolyte exhibits superior stability over commercial carbonate electrolytes at all tested temperatures (32°C, 45°C, and 60°C). Although thermal analysis during the first charge process (as adopted in this preliminary study) may be insufficient to conclude the long-term advantages of these electrolytes, a more stable electrolyte identified under extreme voltage and temperature conditions will provide valuable guidance for the safety of future electrolyte designs.

25 ENERGY STORAGE↗
DOE OSTI2020

Development of Advanced Ultra-Supercritical (AUSC) Pulverized Coal (PC) Plants

This report presents an independent assessment of pulverized coal (PC) power plants operating at advanced ultrasupercritical (AUSC) steam conditions. At AUSC conditions, PC plants generate electricity at higher efficiencies and with lower carbon footprints than PC plants operating at subcritical, supercritical (SC), and ultrasupercritical (USC) steam conditions, such as those examined in previous National Energy Technology Laboratory (NETL) reports. However, advanced materials are required for commercial operation under these AUSC steam conditions which impact plant economics. In 2001, the United States (U.S.) Department of Energy (DOE) with the Ohio Coal Development Office launched a research program carried out by a consortium of industry and research organizations (the AUSC Consortium) to develop the materials necessary to commercially demonstrate AUSC technology. The results contained in this report incorporate findings by the AUSC Consortium.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2025

The 8RH 2 Process for Producing Clean Hydrogen with Autothermal Reforming and Carbon Capture

The primary objective of this project is to demonstrate the commercial viability and environmental benefits of an 8 Rivers Hydrogen (8RH 2 ) process, a proprietary technology developed to optimally produce high-purity blue H 2 with up to 99% carbon capture. This 8RH 2 process is particularly notable for its integration of a low-energy cryogenic CO 2 separation system that not only maximizes hydrogen recovery but also minimizes the carbon footprint of the operation. This aligns with global environmental goals and supports the United States' push toward energy sustainability and independence.

03 NATURAL GAS↗
NASA NTRS1967

Development of low temperature battery

Self-contained low temperature battery system consisting of a magnesium anode, potassium thiocyanate-ammonia electrolyte and a cathode composed of a mixture of sulfur, carbon, and mercuric sulfate operates for at least seventy-two hours within a discharge temperature range of plus 20 degrees C to minus 90 degrees C.

Armstrong, G. M.↗