Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Hydrogen Storage”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Risk assessment of wellbore leakage during underground hydrogen storage

The expansion of renewable energy sources would require large-scale energy storage options to overcome the intermittent nature of these sources. Underground hydrogen storage (UHS) in depleted hydrocarbon reservoirs offers a scalable and practical energy storage solution. These reservoirs are chosen for their availability and large capacity, but the unique properties of hydrogen raise concerns about potential leakage pathways, particularly through wellbores. In this study, we develop and apply, for the first time, reduced-order models (ROMs) specifically designed for efficient leakage risk prediction in UHS systems operating in depleted hydrocarbon reservoirs. Using 3,000 high-fidelity simulation scenarios, we examine the influence of 11 key parameters, including reservoir and aquifer depths, wellbore permeability and porosity, initial saturations of water, oil and gas fractions (hydrogen, light, intermediate, and heavy hydrocarbons), reservoir pressure multiplier, and the aquifer-to-reservoir volume ratio, to simulate leakage behavior over a 1,000-year timescale. We train ROMs using a two-step classification-regression approach, achieving R 2 values exceeding 99 % across all targets. These ROMs effectively capture the leakage evolution and identify critical controls of leakage, guiding the design of mitigation strategies. Results indicate that gas leakage occurs in about 27 % of scenarios as early as five years post-operation, reaching volumes of up to 106 ft3. Oil leakage is less frequent (~17 %) and typically begins decades later. Our findings also show that hydrogen often migrates first, owing to its smaller molecular size and higher buoyancy, followed by heavier hydrocarbons. Over time, these heavier components contribute significantly to the total leaked volume, reinforcing the need for targeted monitoring and remediation strategies. Our analysis highlights that deeper storage reservoirs, shallower aquifers, and low-permeability wellbores significantly reduce leakage risks. In conclusion, this work offers a robust framework for risk-informed UHS deployment, supporting energy security through reliable large-scale hydrogen storage while safeguarding environmental integrity.

08 HYDROGEN↗
DOE OSTI2026

Innovations in underground hydrogen storage with multiphysics simulations, optimization, and monitoring: A review

Underground Hydrogen Storage (UHS) is a promising solution for large-scale energy storage and a critical component in advancing low-carbon energy system. Ensuring the safety and efficiency of UHS necessitates a comprehensive understanding of multiphysical interactions driven by cyclic pore fluid pressure fluctuations and coupled physicochemical processes. Here, this review examines the key geomechanical responses in UHS, including rock property variations under cyclic loading, fracture evolution and propagation, reservoir stress sensitivity, and fault stability. It also explores the impact of geochemical and microbial reactions on geomechanical characteristics. We provide an in-depth analysis of Thermal-Hydraulic-Mechanical-Chemical (THMC) coupled numerical simulations, highlighting their potential for future multi-scale modeling. Limitations of current machine learning (ML) approaches in addressing UHS challenges are highlighted, emphasizing the need for innovative ML-based methodologies. Operational strategies for hydrogen injection and production are reviewed, focusing on safety, efficiency, and economic viability. The necessity for multi-objective optimization (MOO) to balance storage efficiency, risk mitigation, and cost-effectiveness is also discussed. Current monitoring technologies are evaluated to ensure safe and efficient UHS operations. Finally, this review identifies critical knowledge gaps and underscores the importance of advancing geomechanical understanding under multiphysics-coupling. We highlight the need for ML-driven multiphysics theories, enhanced modeling techniques, and robust optimization strategies to improve UHS performance. This study serves as a comprehensive reference for future research and the large-scale implementation of UHS systems.

25 ENERGY STORAGE↗
DOE OSTI2025

Laboratory evaluation of cyclic underground hydrogen storage in the Temblor sandstone of the San Joaquin Basin, California

Underground Hydrogen Storage (UHS) in depleted oil and gas reservoirs could provide a cost-effective solution to balance seasonal fluctuations in renewable energy generation. However, data and knowledge on UHS at subsurface conditions are limited so it is difficult to estimate how effective this type of storage could be. In this study, we perform high pressure experiment to measure the effectiveness of cyclic hydrogen (H 2 ) storage in a specimen of Temblor sandstone retrieved from the San Joaquin Basin of California. Our experiment mimics reservoir pressure conditions to measure H 2 -brine relative permeability and fluid-rock interactions over the course of ten charging and discharging cycles. Initial gas breakthrough occurred at 15 % to 25 % H2 saturation in the specimen with 3 % NaCl brine as the resident fluid. Continuing injecting to 4 pore volumes (PV) of H 2 yielded an asymptotic H 2 saturation of 38 % to 41 %, a level often referred to as the irreducible gas saturation based on two-phase flow. The boundary condition in this study mimics the near wellbore region, which experiences bi-directional H 2 flow. This bi-directional flow led to evaporative drying of the specimen resulting in 94 % H 2 saturation at the end of 10th cycle. This indicates that cyclic flow and evaporative drying can lead to more efficient reservoir storage where a larger fraction of the reservoir porosity is usable to store H 2 . The produced gas stream consisted of H 2 mixed with 8 % to 22 % H 2 O, indicating formation dry-out by evaporation. Meanwhile, produced water chemistry indicated calcite and silicate dissolution, with calcite sourced from fossil fragments. This led to a loss of cementation and weakened the rock sample. Combined, our results indicate dry-out, compaction, increased H 2 saturation, rock weakening, and permeability loss during cyclic UHS. Overall, we anticipate that the combined effects should lead to higher than anticipated UHS storage efficiency per volume of sandstone reservoir rock.

08 HYDROGEN↗
NASA NTRSDate not supplied

Experimental Investigation of a Physisorption-Based Hydrogen Storage System

This study discusses a practical system utilizing the principle of physisorption where hydrogen is weakly bound to the surface of a nanoporous silica aerogel blanket as an alternative to high-pressure and cryogenic hydrogen storage. Three different experiments are conducted to simulate various scenarios of such a storage method: change in pressure and change of scale. Transient responses of the charging and discharging cycles are of particular interest. It is observed that hydrogen uptake can be increased by up to 36-38 % at ambient conditions and 77 K when utilizing the aerogel blankets. Packing density, or the artificial increase of surface per volume, increases storage capacity as it is a mainly surface-driven phenomenon. High-pressure testing up to 50 bar showed benefits of the aerogel addition whereas the maximum uptake improvement was observed for 2 bar with a 105.3 % improvement over an empty vessel at identical conditions corresponding to 6.43 wt%. The scale-up of the system is highly sensitive to the design of the internal cooling design as aerogels are poor thermal conductors reducing the transient response of such systems. Furthermore, the high mass of metal-based pressure vessels further delays the thermal response. This makes the system suitable for day to week-long hydrogen storage but not for peak-shaving or load balancing.

Marcel Otto↗
NASA NTRSDate not supplied

Vacuum Pump-Down of the Annular Insulation Space for Large Field-Erected Liquid Hydrogen Storage Tanks

Insulation systems are critical to liquid hydrogen storage tank performance. Tanks in the capacity range of 100 to 1,000 m 3 are typically shop built and designed with high-vacuum (HV) multi-layer insulation (MLI), whereas storage vessels larger than 1,000 m 3 are typically field-erected and supplied with bulk fill insulation working at moderate vacuum (MV) levels (1-100 millitorr). For large, field-erected vessels, two types of bulk fill insulation typically used: perlite and hollow glass microspheres (glass bubbles). Selection of either material is driven by a tradeoff between CAPEX and OPEX, such as the material and construction cost versus operating thermal performance and maintenance. In either case, the vacuum level needed to achieve optimum performance is likely to drive the field testing and commissioning portion of the construction schedule. A primary goal of this paper is to present practical experience and data for warm vacuum pressure (WVP) and cold vacuum pressure (CVP) levels. Recommended WVP levels needed prior to cooldown consider both perlite powder and glass bubbles. Pumping time expected to achieve target vacuum levels, considering a variety of factors, is also discussed. Recommendations for a standard practice in vacuum-insulated tank commissioning are based on historical NASA data, and those collected during recent projects.

A M Swanger↗
DOE OSTI2025

Hydrogen Storage Engineering Center of Excellence Adsorbent (Final Report)

The Hydrogen Storage Engineering Center of Excellence (HSECoE) team would like to thank the U.S Department of Energy’s (DOE) Hydrogen and Fuel Cell Technologies Office for the funding to embark on such a large endeavor to develop the material and engineering science related to the use of adsorbents as the storage media for automotive applications. In addition, SRNL would like to thank the many partners of the HSECoE including U.S. automotive manufacturers, GM and Ford, potential component and materials suppliers, United Technologies Research Center, Hexagon Lincoln Composites, and BASF, Universities, Oregon State University, University of Michigan, and the University of Québec, Trois Reveres, along with the Jet Propulsion Laboratory, Pacific Northwest National Laboratory, Los Alamos National Laboratory and Savannah River National Laboratory. Individual specific contributions can be found in individual final reports submitted to DOE. No attempt is made here to attribute contributions to individual people or organizations, illustrating the cooperative arrangement of the team members.

08 HYDROGEN↗
DOE OSTI2025

Potential Risks Associated with Short-Term Hydrogen Storage in Methane Reservoirs

Hydrogen (H2) has been identified as a flexible energy carrier with zero emissions. It is possible to utilize H2 by storing Hyblend, or H2 blended with CH4, in existing natural gas infrastructure. However, the compatibility of adapting the current CH4 storage strategies to include H2 injection has not been fully demonstrated. It is essential that we understand the impact of H2 gas on the naturally occurring microbial community of subsurface storage reservoirs before deploying large-scale H2-CH4 storage. We designed a series of experiments that allowed us to identify potential challenges of HyBlend Storage in existing methane reservoirs (Figure 1). First, we characterized two field fluid samples from a methane reservoir located in Western United States. Next, we used these samples to complete a series of short-term reactor experiments at reservoir conditions for a natural gas (100% CH4) and HyBlend (80% CH4/20% H2) storage environment.

geomicrobiology↗
DOE OSTI2025

Machine learning-assisted design of metal–organic frameworks for hydrogen storage: A high-throughput screening and experimental approach

Various theoretical approaches, including big data and high-throughput screening techniques, have been explored in developing new materials due to their significant potential time-saving advantages. However, it remains a significant challenge to experimentally realize new materials that are predicted. In this study, we propose a novel materials design strategy that utilizes machine-learning (ML) techniques to predict new porous materials that show promise for hydrogen storage and are likely to be feasible to synthesize. By leveraging ML techniques and metal–organic framework (MOF) databases, we are able to predict the synthesizability of MOF structures. This is evidenced by the successful synthesis of a new vanadium-based MOF that exhibits excellent performance for cryogenic H 2 storage. Notably, the total gravimetric and volumetric H 2 uptakes are as high as 9.0 wt% and 50.0 g/L at 77 K and 150 bar. This ML-assisted materials design offers an efficient and promising approach for developing hydrogen storage materials.

08 HYDROGEN↗
NASA NTRS2019

Return to Service of a Liquid Hydrogen Storage Sphere

One, of two, 850,000 gallon liquid hydrogen storage spheres, at NASA's Kennedy Space Center, was decommissioned in 2010. This tank had an abnormally high heat leak that was investigated and determined to be the result of a large void in the perlite insulation. The insulation void was subsequently filled, and the tank was refurbished for its planned use in the Space Launch Systems (SLS) program. Return to service of this tank began in December of 2017 with a partial liquid hydrogen fill. Since that time, routine measurement of the liquid level have been recorded in order to establish a new boiloff rate and associated heat leak. This data shows the perlite top off activities have resulted in a much reduced, and within design specification, heat leak.

air leak↗
NASA NTRS2019

Return to Service of a Liquid Hydrogen Storage Sphere

One, of two, 850,000 gallon liquid hydrogen storage spheres, at NASA's Kennedy Space Center, was decommissioned in 2010. This tank had an abnormally high heat leak that was investigated and determined to be the result of a large void in the perlite insulation. The insulation void was subsequently filled, and the tank was refurbished for its planned use in the Space Launch Systems (SLS) program. Return to service of this tank began in December of 2017 with a partial liquid hydrogen fill. Since that time, routine measurement of the liquid level have been recorded in order to establish a new boiloff rate and associated heat leak. This data shows the perlite top off activities have resulted in a much reduced, and within design specification, heat leak.

Krenn, A. G.↗
DOE OSTI2026

Enhancing Room-Temperature Hydrogen Storage Properties in Ti–V–Cr–Nb–Mo/Fe Multielement Alloys via Substitutional Tuning

Building upon previously reported high-entropy alloys (HEA) in the Ti−V−Cr−Nb−Mo/Fe compositional space, this study presents a novel bcc alloy containing 6 at. % of the earthabundant element Fe, exhibiting enhanced hydrogen storage properties at room temperature (25 °C). The optimized bcc Ti 23 V 30 Nb 10 Cr 31 Fe 6 alloy rapidly absorbs hydrogen at room temperature with a maximum gravimetric capacity of 3.4 wt % and an enthalpy of hydride formation of −34 kJ/mol H 2 . This value is among the lowest reported to date for bcc HEAs. The reversible capacity of this alloy remains stable at 2.0 wt % upon 20 absorption/desorption cycles at room temperature, which is among the highest reported values for this material class. Collectively, these advances highlight the potential of Fecontaining multielement alloys as efficient and economical candidates for next-generation hydrogen storage systems.

08 HYDROGEN↗
DOE OSTI2025

Fabrication and characterization of nanoscale magnesium diboride and tetraboride for propulsion and hydrogen storage applications

Abstract: Boron-loaded propellants have the potential to dramatically increase the performance of solid fuel ramjets, ducted rockets, and hybrid rocket engines. However, difficult ignition of boron decreases the combustion efficiency of these propellants. One approach to solving this problem involves the use of magnesium diboride, MgB2, which ignites easier than boron. Magnesium tetraboride, MgB4, potentially offers greater energetic performance as B has a higher energy density than Mg. However, the effect of the higher boron/metal ratio on the ignition and combustion is unclear. Nanoscale MgB2 particles and quasi 2D structures are promising propellant ingredients, but the oxidation and combustion properties of nanoscale MgB4 remain unknown. Nanoscale magnesium borides are also of interest as precursors for the synthesis of magnesium borohydride, Mg(BH4)2, a promising hydrogen storage material, but hydrogenation of MgB4 has not been studied yet. The objectives of the present work included synthesis, purification, and high-energy ball milling of MgB2 and MgB4 powders as well as investigation of their hydrogen uptake, thermal decomposition, oxidation, and combustion. The powders were fabricated by combustion synthesis and by heating in a tube furnace. The latter method was superior in the synthesis of MgB4. Oxide impurities in the synthesized powders were removed by acid leaching. Nanoscale powders were obtained by ball-mill exfoliation. The hydrogen intake of the obtained magnesium borides was examined at 700 bar and 300 ℃ and did not reveal any advantage of MgB4 over MgB2. Their thermal decomposition and oxidation were investigated with thermogravimetric analysis (TGA), while their combustion was studied using laser ignition and high-speed video recording. TGA has confirmed prior observations of multistep decomposition of magnesium borides, where each step involves formation of a boride with a higher B/Mg ratio and evaporation of formed magnesium. The oxidation rates of the borides are much higher than that of boron at temperatures over 1200 °C for MgB2 and over 900 °C for MgB4. The burning rates of non-milled MgB₂ and MgB₄ powders were much higher than for the used submicron boron. Milling the MgB₂ and MgB₄ powders further increased their burning rates. The milled MgB4 burned 7.5 times faster than submicron boron.

Combustion of metals, Solid fuels, Propellants, Hy↗
NASA NTRS2005

Catalytic Metal Free Production of Large Cage Structure Carbon Particles: A Candidate for Hydrogen Storage

We will demonstrate that carbon particles consisting of large cages can be produced without catalytic metal. The carbon particles were produced in CO gas as well as by introduction of 5% methane gas into the CO gas. The gas-produced carbon particles were able to absorb approximately 16.2 wt% of hydrogen. This value is 2.5 times higher than the 6.5 wt% goal for the vehicular hydrogen storage proposed by the Department of Energy in the USA. Therefore, we believe that this carbon particle is an excellent candidate for hydrogen storage for fuel cells.

Kimura, Yuki↗
DOE OSTI2025

Foam-insulated cryo-compressed hydrogen storage vessels for buses

Here, large reductions (40 % vs. compressed gaseous hydrogen vessels and 17 % vs. vacuum insulated cryo-compressed vessels) in hydrogen storage system cost are possible by operating buses with foam-insulated cryo-compressed hydrogen (CcH 2 ) vessels. Detailed thermodynamic analysis reveals that large size and rapid H 2 consumption in buses compensate for the poor performance of foam insulation (∼100 times more conductive than vacuum multilayer insulation), resulting in compact and inexpensive H 2 storage systems with sufficient H 2 capacity for the longest routes (500 km) while maintaining previously identified advantages of CcH 2 systems: increased autonomy, rapid high density refueling, and improved safety, while simultaneously avoiding vacuum insulation stability problems resulting from composite resin outgassing.

Cryo-compressed↗
NASA NTRS1992

Capacity retention in hydrogen storage alloys

Results of our examination of the properties of several candidate materials for hydrogen storage electrodes and their relation to the decrease in H-storage capacity upon open-circuit storage over time are reported. In some of the alloy samples examined to date, only about 10 percent of the hydrogen capacity was lost upon storage for 20 days, while in others, this number was as high as 30 percent for the same period of time. This loss in capacity is attributed to two separate mechanisms: (1) hydrogen desorbed from the electrode due to pressure differences between the cell and the electrode sample; and (2) chemical and/or electrochemical degradation of the alloy electrode upon exposure to the cell environment. The former process is a direct consequence of the equilibrium dissociation pressure of the hydride alloy phase and the partial pressure of hydrogen in the hydride phase in equilibrium with that in the electrolyte environment, while the latter is related to the stability of the alloy phase in the cell environment. Comparison of the equilibrium gas-phase dissociation pressures of these alloys indicate that reversible loss of hydrogen capacity is higher in alloys with P(eqm) greater than 1 atm than in those with P(eqm) less than 1 atm.

Anani, A.↗
DOE OSTI2025

Underground Hydrogen Storage: Transforming Subsurface Science into Sustainable Energy Solutions

As the global economy moves toward net-zero carbon emissions, large-scale energy storage becomes essential to tackle the seasonal nature of renewable sources. Underground hydrogen storage (UHS) offers a feasible solution by allowing surplus renewable energy to be transformed into hydrogen and stored in deep geological formations such as aquifers, salt caverns, or depleted reservoirs, making it available for use on demand. This study thoroughly evaluates UHS concepts, procedures, and challenges. This paper analyzes the most recent breakthroughs in UHS technology and identifies special conditions needed for its successful application, including site selection guidelines, technical and geological factors, and the significance of storage characteristics. The integrity of wells and caprock, which is important for safe and efficient storage, can be affected by the operating dynamics of the hydrogen cycle, notably the fluctuations in pressure and stress within storage formations. To evaluate its potential for broader adoption, we also examined economic elements such as cost-effectiveness and the technical practicality of large-scale storage. We also reviewed current UHS efforts and identified key knowledge gaps, primarily in the areas of hydrogen–rock interactions, geochemistry, gas migration control, microbial activities, and geomechanical stability. Resolving these technological challenges, regulatory frameworks, and environmental sustainability are essential to UHS’s long-term and extensive integration into the energy industry. This article provides a roadmap for UHS research and development, emphasizing the need for further research to fully realize the technology’s promise as a pillar of the hydrogen economy.

25 ENERGY STORAGE↗