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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 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

Reports From The Frontier: Overcoming Limitations for Pure-water Anion-exchange-membrane Electrolysis

Anion-exchange-membrane electrolysis is positioned to play a key role in the predicted exponential growth of green hydrogen technology with essential R&D advances. We reveal key design parameters essential to commercialization. First, stable alkaline oxygen-evolution reaction catalysts with high electronic conductivity and minimal surface reconstruction during operation must be designed. Alkaline catalyst layers must also be applied to the membrane electrode assembly with scalable, industrially relevant techniques. Second, ionomer oxidation mitigation strategies must be developed. Furthermore, this approach could also target other creative catalyst layer design, such as phase-separation control to protect oxidation-prone organic components or catalyst engineering to direct selectivity for hydroxide over polymer oxidation. If competitive efficiency and durability can be achieved in pure water, AEM electrolysis has the potential to become a dominant electrolyzer technology.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

Development of an Advanced Hydrogen Energy Storage System using Aerogel in a Cryogenic Flux Capacitor

The Cryogenic Flux Capacitor (CFC) is a cold, dense fluid storage core with integrated design features that afford the designer flexibility and provide new possibilities for the storage and discharge of energy. The stored energy, in this case, is represented by hydrogen physically bonded within the nanoscale pores within the aerogel composite blanket material, and the process of bonding or debonding is governed by the principles of physical adsorption (physisorption) and thermodynamics. The large surface area afforded by the nanoporous aerogel (~1,000 m 2 /g) allows for storage densities close to, or in some cases exceeding, that of normal boiling point liquids. Its performance easily exceeds what can be achieved via ambient temperature and high-pressure gas storage for an equivalent volume. CFC storage is predicted to be easily scalable, constructed from readily available commercial materials, and lends itself to a range of pressure applications. The project team designed and manufactured the CFC, integrating it into a set of temperature-controlled flow loops. The CFC test setup was validated against existing data from previous NASA work. Tests used bottled hydrogen gas for test validation. A cryogenic fluid, nitrogen, flowed through a metered control system. Hydrogen temperature, pressure, and flow rates, as well as the temperature control targets, provided all necessary control targets. The team analyzed the recorded data and updated the Technology Maturation Plan based on the results of the test, making recommendations for a follow-up test, scale-up, and maturation pathway. For the engineering development and maturation of CFC hydrogen storage technology, a Techno-Economic Assessment (TEA) and Commercialization Plan for the integration of this technology with various power generation assets were produced. A companion analytical model was developed, experimentally validated, compared against performance metric, and used to tune the model and scale up the technology.

08 HYDROGEN↗
DOE OSTI2024

Aryl ether-free polymer electrolytes for electrochemical and energy devices

Anion exchange polymers (AEPs) play a crucial role in green hydrogen production through anion exchange membrane water electrolysis. The chemical stability of AEPs is paramount for stable system operation in electrolysers and other electrochemical devices. Given the instability of aryl ethercontaining AEPs under high pH conditions, recent research has focused on quaternized aryl ether-free variants. The primary goal of this review is to provide a greater depth of knowledge on the synthesis of aryl ether-free AEPs targeted for electrochemical devices. Synthetic pathways that yield polyaromatic AEPs include acid-catalysed polyhydroxyalkylation, metal-promoted coupling reactions, ionene synthesis via nucleophilic substitution, alkylation of polybenzimidazole, and Diels–Alder polymerization. Polyolefinic AEPs are prepared through addition polymerization, ring-opening metathesis, radiation grafting reactions, and anionic polymerization. Discussions cover structure–property–performance relationships of AEPs in fuel cells, redox flow batteries, and water and CO 2 electrolysers, along with the current status of scale-up synthesis and commercialization.

25 ENERGY STORAGE↗
DOE OSTI2024

Science Driven Discovery of Nanoparticle Photocatalysts

Photocatalytic water splitting using suspensions of nanoparticle photocatalysts is a promising route to economically sustainable production of green hydrogen. The principal challenge is to develop photocatalysts with overall solar-to-hydrogen conversion efficiency that exceeds 10 percent. In this project we have developed a new platform for investigating candidate materials for photocatalytic water splitting. Our platform consists of patterned Au electrodes and a Ag/AgCl reference electrode on an insulating substrate onto which we disperse nanoparticle photocatalysts. We then cover the substrate with a thin layer of ionogel containing a protic ionic liquid that dissolves water from the ambient. Using this platform we have demonstrated photoelectrochemical activity mapping for single and small clusters of BiVO 4 nanoparticle photocatalysts and correlated these results to their Raman and photoluminescence spectra. The preliminary results suggest a strong correlation for low efficiency nanoparticles, followed by saturation for those with higher activities, indicating that interface reaction or electrolyte transport become the limiting factor. We anticipate that further application of this platform to investigation of candidate photocatalyst materials will provide useful insights into the mechanisms that limit their performance.

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2024

Cyber-Physical Simulation of an Innovative Solid Oxide Electrolysis Cell - Gas Turbine (SOEC-GT) Hybrid Energy System

To produce green hydrogen at scale and at low cost, the solid oxide electrolysis cell (SOEC) systems would be tied to renewable power sources (mainly solar and wind), leveraging zero-carbon electricity at low prices and even nearly free during overgeneration scenarios. However, due to the intermittency of renewable power generation, the SOEC system is subjected to rapid load transitions that occur not only in diurnal cycles but also in short timeframes (e.g., sub-minute). This can result in fast degradation and thus greatly reduce the SOEC’s lifetime. Our team at the National Energy Technology Laboratory has demonstrated that the anode air flow can have a crucial role in SOEC thermal management. Typically, a higher air flow rate can help to mitigate the local temperature gradient distortion during rapid load transitions. To move a large amount of air, the gas turbine (GT; i.e., compressor-turbine-generator set) has been regarded as the most mature and efficient technology. In this presentation, we show the configuration and preliminary results of an innovative SOEC-GT hybrid energy system in a cyber-physical simulation (CPS) approach.

Zhang, Biao↗
DOE OSTI2023

Techno-economic Analysis of the Cryogenic Flux Capacitor Compared to Other forms of Hydrogen Production and Storage

The Cryogenic Flux Capacitor (CFC) is a cold, dense energy storage core that is being studied in the cryo-compressed, about 300 bar and 80K, region of gaseous hydrogen (GH2) storage and liquid hydrogen (LH2) region near the normal boiling point. The hydrogens storage is improved by physically bonding the molecules within the nanoscale pores of the aerogel composite blanket material. The process of bonding or debonding is governed by principles of physical adsorption (physisorption) and thermodynamics. The large surface area afforded by the nanoporous aerogel (~1,000 m2/g) allows its storage performance to easily exceed capacities of high-pressure GH2 storage for an equivalent volume. With the integrated aerogel, subscale tests have shown that storage is increased by about 49% over a simple tank filled with GH2 at the same operating temperature and pressure. For LH2 conditions, the CFC is shown to operate at equivalent densities. For the techno-economic analysis (TEA), the source of hydrogen is compared between onsite steam methane reforming (SMR) and onsite solar photovoltaic (PV) panels providing power to electrolyzers to produce GH2. The TEA compares pure hydrogen burning in a combined cycle gas turbine (CCGT) to hydrogen fuel cells with an overall net power output of 650 MW. The SMR system uses natural gas as an input and includes a carbon capture and storage (CCS) system. The levelized cost of electricity is developed based on the capital cost and operating cost of the systems. Sensitivities are discussed around the cost of natural gas, ranging from 1.93 USD per MMBTU to 6.75 USD per MMBTU, and carbon dioxide disposal, ranging from 7 USD per tonne to 10 USD per tonne. For comparison to the conventional CCGT baseline, a baseload scenario is adopted with 85% capacity factor. The results of the study show that onsite hydrogen generation from SMR is about 1 to 3 USD per kg over the life of the plant and the PV hydrogen production produces at 4 to 5 USD per kg. The cost of storage for CFC is compared to other systems, including high-pressure GH2 and atmospheric LH2. The system is shown to provide the lowest costs for all these options at the grid scale, due to its higher capacity than high-pressure GH2 and ability to operate at 80K, receiving refrigeration from liquid nitrogen systems reducing capital and operating costs when compared LH2 storage systems. SMR is competitive with CCGT at the gas prices, both of which have lower LCOE than the PV system. When accounting for variability in gas prices, the PV and electrolyzer system is less sensitive to these changes and provides the lowest LCOE across the whole range.

08 HYDROGEN↗
DOE OSTI2024

Development and Commercialization of a Nanosegrated Oxygen Evolution Reaction Electrocatalyst (CRADA)

This collaborative project leverages advanced characterization tools, catalyst treatment and electrochemical testing capabilities at LBNL to help commercialize a bimetallic nanosegrated catalysts for oxygen evolution reaction in proton-exchange membrane water electrolyzers. This project also has three industrial partners who are involved in catalyst scale-up synthesis, large electrode fabrication and large electrode electrochemical testing. This project investigates a broad range of topics including electrocatalysis, ink rheology and electrode fabrication and testing. This knowledge could help bridge the performance and durability gap from laboratory-developed materials (such as electrocatalysts) to applications in commercial devices. The research results also bring fundamental understanding of possible degradation mechanisms that occur under extremely oxidative potentials including material and morphological changes. The project will help accelerate the deployment of proton-exchange membrane water electrolyzers. The public benefits could include creating jobs and increasing public awareness of potential clean technologies for green hydrogen production. Ultimately, the project will help national wide effort of flighting climate change and achieving carbon neutrality by 2050.

30 DIRECT ENERGY CONVERSION↗
DOE OSTI2025

High-Efficiency Low-Carbon Fuel Flexible Burner for Steel Industry

GTI Energy, with Bloom Engineering, Argonne National Laboratory and Oak Ridge National Laboratory, are developing the FlexGen-H burner. This high-efficiency burner can achieve 45•100% CO2e emissions reduction using green hydrogen with natural gas. It offers NOx, CO emissions ?50 ppm (3% O2), 15•51% fuel savings, ?50% PM2.5 reduction with turndown of ?5:1. The technology can work with renewable liquid fuels, ethanol or methanol. The technology aims to significantly reduce emissions, enhance resiliency, improve process efficiency. The paper will discuss preliminary results of development, with planned laboratory validation including safety, CFD, burner system design and market for the technology.

Sperry, McKay [ORNL] (ORCID:0009000658602049)↗
DOE OSTI2022

Assessing the Oxidative Stability of Anion Exchange Membranes in Oxygen Saturated Aqueous Alkaline Solutions

While anion exchange membrane water electrolyzers show promise as a source of green hydrogen using low-temperatures and non-platinum group metal catalysts, many concerns must be addressed. A primary challenge for the development of high-performance anion exchange membrane water electrolyzers is the fabrication of a stable membrane that will be able to survive long-term stability test while maintaining high anion conductivity, which is a necessity for a durable water electrolyzer. This method will present a standardized protocol that can be used by researchers to assess the quality of their AEM materials and be able to provide insight into how materials may be degrading and how to improve the quality of AEMs. Using Mohr or Volhard titration to measure ion-exchange capacity, EIS to determine the ionic conductivity, NMR and FTIR to understand the extent of membrane degradation over time, and mechanical analyzers to determine the strength of their AEMs, this standardized protocol will guide researchers to determining and improving upon the long-term durability and performance of their AEM materials.

36 MATERIALS SCIENCE↗
DOE OSTI2021

The Influence of Transitional Metal Dopants on Reducing Chlorine Evolution during the Electrolysis of Raw Seawater

Electrocatalytic water splitting is a possible route to the expanded generation of green hydrogen; however, a long-term challenge is the requirement of fresh water as an electrolyzer feed. The use of seawater as a direct feed for electrolytic hydrogen production would alleviate fresh water needs and potentially open an avenue for locally generated hydrogen from marine hydrokinetic or off-shore power sources. One environmental limitation to seawater electrolysis is the generation of chlorine as a competitive anodic reaction. This work evaluates transition metal (W, Co, Fe, Sn, and Ru) doping of Mn-Mo-based catalysts as a strategy to suppress chlorine evolution while sustaining catalytic efficiency. Electrochemical evaluations in neutral chloride solution and raw seawater showed the promise of a novel Mn-Mo-Ru electrode system for oxygen evolution efficiency and enhanced catalytic activity. Subsequent stability testing in a flowing raw seawater flume highlighted the need for improved catalyst stability for long-term applications of Mn-Mo-Ru catalysts. This work highlights that elements known to be selective toward chlorine evolution in simple oxide form (e.g., RuO2) may display different trends in selectivity when used as isolated dopants, where Ru suppressed chlorine evolution in Mn-based catalysts.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2024

The Role of Low-Carbon Fuels and Carbon Capture in Decarbonizing the U.S. Clinker Manufacturing for Cement Production: CO2 Emissions Reduction Potentials

Low-carbon fuels, feedstocks, and energy sources can play a vital role in the decarbonization of clinker production in cement manufacturing. Fuel switching with renewable natural gas, green hydrogen, and biomass can provide a low-carbon energy source for the high-temperature process heat during the pyroprocessing steps of clinker production. However, up to 60% of CO2 emissions from clinker production are attributable to process-related CO2 emissions, which will need the simultaneous implementation of other decarbonization technologies, such as carbon capture. To evaluate the potential of fuel switching and carbon capture technologies in decarbonizing the cement industry, a study of the facility-level CO2 emissions is necessary. This study evaluates the potential for using a single low-carbon fuel as an energy source in clinker production for cement manufacturing compared to conventional clinker production (which uses a range of fuel mixes). In addition, conventional carbon capture (operated with natural gas-based steam for solvent regeneration) and electrified carbon capture configurations were designed and assessed for net-zero emission targets. Carbon emissions reductions with and without biogenic emissions credits were analyzed to ascertain their impact on the overall carbon accounting. Results show that carbon emissions intensity of cement can vary from 571 to 784 kgCO2eq/metric ton of cement without carbon capture and from 166.33 to 438.66 kgCO2eq/metric ton of cement with carbon capture. We find that when biogenic carbon credits are considered, cement production with a sustainably grown biomass as fuel source coupled with conventional carbon capture can lead to a net-negative emission cement (−271 kgCO2eq/metric ton of cement), outperforming an electrified capture design (35 kgCO2eq/metric ton of cement). The carbon accounting for the Scope 1, 2, and biogenic emissions conducted in this study is aimed at helping researchers and industry partners in the cement and concrete sector make an informed decision on the choice of fuel and decarbonization strategy to adopt.

42 ENGINEERING↗
DOE OSTI2025

Repurposing Offshore Infrastructure for Clean Energy (ROICE) vs. Decommissioning – Commercial Considerations

Abstract The Repurposing Offshore Infrastructure for Clean Energy (ROICE) Program, a collaboration of the energy industry and University of Houston, proposes extending the life of up to 1,500 oil and gas platforms in the Outer Continental Shelf of the Gulf of Mexico, USA. Rather than decommissioning or converting them to underwater reefs at the end of their oil and gas production phase, the platforms could be transformed for 10–20+ years of renewable energy development, such as green hydrogen production or carbon dioxide injection and storage, resulting in significant economic, environmental, and social benefits. ROICE has already published papers on the technical and regulatory considerations for such repurposing projects. This paper focuses on the commercial considerations needed to ensure ROICE projects are economically viable and sustainable for all involved. There are potentially many entities that can come together to progress a repurposing project, including oil and gas asset owners, operators, investors, developers, contractors, manufacturers, and regulators. This paper looks at possible combinations of these entities in a ROICE project team and the various commercial agreements that will be needed to ensure a mutually successful outcome. The paper proposes adapting existing industry agreements and templates to suit, including asset transfer agreements (ATA), asset purchase agreements (APA) and joint purchasing agreements (JOA). An ATA or APA can be drafted to address the obligations and issues involved in the sale or transfer of an existing oil and gas facility to the developer, operator, non-operating interests, and financial investors in a ROICE project, while a JOA can be drafted to govern the rights, obligations, and financial requirements of the parties involved in the development and operation.

Legge, G. [Endeavor Management, USA]↗
DOE OSTI2022

Optimal Wind Turbine Design for H2 Production

NREL and industrial partners GE and Nel seek to advance affordable green hydrogen production by optimizing wind turbine design specifically for hydrogen production and validating designs using NREL's ARIES facilities. This project will couple wind turbine, wind plant, solar plant, and electrolyzer models to predict hydrogen production from variable, renewable power sources. It will then use gradient-based optimization with exact-analytic gradients to optimize wind turbine rotor diameter, hub height, and power rating for optimal hydrogen production. Finally, it will validate the optimal turbine designs using the ARIES research platform, where it will compare a baseline turbine to the optimal design for a variety of scenarios and resources.

electrolyzer↗
DOE OSTI2023

Direct Numerical Simulation of Flame-Wall Interaction for Low-Carbon Gas Turbine Combustion

Green hydrogen (H2) and ammonia (NH3) are emerging as carbon free alternatives to hydrocarbon fuels. In gas turbines, flames interact with the combustor liner (wall), which affects the pollutant emissions, the burning efficiency, and the thermal load on the liner. We lack understanding of this important flame-wall interaction (FWI) for alternative fuels. FWI occurs at the scale of the flame thickness, and such scales are only resolved by direct numerical simulation. Here, we resolve the FWI for NH3 and H2 flames. Preliminary results of two distinct projects are presented: 2D laminar anchored V-flame, and 3D turbulent swirling flame. For the laminar flame, we show flame quenching at the wall and resulting leakage of NH3 and increased N2O, but decreased NO emissions. For the swirling flame, we show CO emissions, and comparison of flame shapes and location to experimental measurements. Ultimately we show that quenching and pollutant emissions strongly affected by fuel/air ratio, and that an inclined wall can stabilize very lean turbulent CH4/H2 flames, but prone to large CO emissions.

adaptive mesh refinement↗
DOE OSTI2024

Advancing Geothermal Research: Fiscal Year 2024 Accomplishments Report

Geothermal resources have delivered renewable electricity for more than 100 years, and renewable heat for far longer, but recent research and advancements have shown that geothermal is more than a 24/7 clean energy source. With the ability to also provide cooling and storage - plus the potential to access critical minerals, capture and sequester carbon, produce green hydrogen, and more - geothermal technologies and resources are emerging as key solutions to the climate crisis. In fiscal year 2024 (FY24), the National Renewable Energy Laboratory (NREL) broadened its research, development, demonstration, and deployment (RDD&D) portfolio and partnerships with exciting innovations such as next-generation geothermal technologies for power, geothermal energy networks for heating and cooling, subsurface thermal energy storage, well repurposing, and more. In support of the U.S. Department of Energy (DOE) Geothermal Technologies Office's (GTO) mission to increase geothermal energy deployment through research, development, and demonstration of innovative technologies that enhance exploration and production, NREL led impactful research in geothermal technologies and resources, market acceleration, and grid integration while also demonstrating leadership in the sector and increasing stakeholder engagement and outreach efforts.

annual report↗
DOE OSTI2024

A country-scale green energy-water-hydrogen nexus: Jordan as a case study

Many developing countries suffer from a shortage of clean energy-water production, causing significant dependency on imported fossil fuel to meet the local energy and freshwater demands. Furthermore, when planning a 100 % renewable energy system (RES) to match the energy demand on an hourly basis, the RES is usually oversized. Hence, unavoidable large amounts of excess energy would be generated during hours of high production, low demand, and fully charged energy storage systems (ESSs). Hence, using Jordan as a case study, this work proposes a novel integrated system of wind, solar photovoltaic (PV), and lithium-ion ESS to match 100 % of the country's energy demand while using the excess generated power to drive reverse osmosis water desalination plants to match the demand of freshwater as well. Furthermore, the remaining excess energy is used for producing green hydrogen. A techno-economic optimizer was developed to show that this concept is indeed feasible. Here, the model was used to scan Jordan for the fitting sites of the highest demand-supply matching and the lowest levelized cost of electricity (LCOE), simultaneously. Three different integration scenarios are presented, namely PV-ESS, wind-ESS, and hybrid PV-wind-ESS RESs. The hybrid system showed the best performance, especially compared to the wind-ESS RES, in terms of total installed capacity (33.37 GW), LCOE (0.0492 USD/kWh), specific water cost (0.3629 USD/m 3 ), and energy and water demand-supply fractions (99.47 and 96.16 %, respectively). Storing desalinated water in natural aquifers was found to be a favorable option to enhance the performance of the three systems, where stored water by the end of the year was sufficient to cover the freshwater requirements for several following years. Finally, the remaining excess energy is used to produce green hydrogen with an annual production of up to 1.37 million tons and a specific cost down to 1.08 USD/kg.

14 SOLAR ENERGY↗
DOE OSTI2025

Comparative life cycle assessment of various hydrogen pathways for cleaner methanol synthesis

This study evaluates the potential environmental impacts of e-methanol production using hydrogen from green, yellow, and blue sources, including Gas Switching Reforming for high purity hydrogen production with carbon capture (GSR-H 2 ), and compares their performance across current and renewable energy scenarios. Using a cradle-to-gate life cycle assessment (LCA), the study quantifies impacts across seven TRACI categories. Global warming potential (GWP) ranged from 0.28 kg CO 2 eq/kg MeOH for green hydrogen with renewables to 2.55 kg CO 2 eq/kg MeOH for SMR-CC under grid power. Among the scenarios, renewable electrolysis achieves the lowest GWP, while GSR-H 2 under renewable power offered the best balance of emissions reductions and resource efficiency among the fossil-based routes, offering a viable transitional solution in regions dependent on natural gas infrastructure. The study reveals GSR-H 2 's potential as an alternative to conventional steam methane reforming with carbon capture (SMR-CC), showing its advantages in carbon capture efficiency and reduced life cycle emissions as well as significantly lower water consumption. GSR-H 2 , when powered by renewables, consumed only 1.41 L of water per kg MeOH, an 82% reduction compared to grid-powered electrolysis, highlighting its potential in water-scarce regions. This study is the first to evaluate GSR-H 2 as a hydrogen source for e-methanol, providing new evidence for its role as a cleaner, scalable transitional solution aligned with cleaner production principles.

08 HYDROGEN↗
DOE OSTI2023

Balancing molecular level influences of intermolecular frustrated Lewis pairs (FLP) for successful design of FLP catalysts for hydrogen storage applications

The rise in energy demands and the deleterious environmental issues related to fossil fuels has led to a surge of interest in hydrogen as a "green" alternative. Hydrogen's extraordinary energy density makes it a potential energy and economic "power"-house. Significant research has been dedicated to materials-based hydrogen storage. One area, liquid organic hydrogen carriers (LOHC) is of substantial interest for the reversible transportation of hydrogen from production to end-use facilities. There are challenges associated with this technology including the dependency on precious metal-based catalysts. Recent work in frustrated Lewis pair (FLP) catalysis demonstrates promise for addressing these challenges. Here this review is focused on assessing recent literature on the utilization of intermolecular FLP main group catalysts for improved hydrogenation/dehydrogenation of various substrates including potential LOHC complexes. This review will present an overview of FLPs, highlight potential hydrogen storage applications, and propose areas where knowledge gaps exist that require further investigations.

08 HYDROGEN↗