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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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Hydrogen Storage High-Capacity Hydrogen Storage for Portable Power Fundamental Hydrogen Interactions for the Development of Advanced Hydrogen Storage Materials Hydrogen for Thermal Energy Storage Leveraging the reversible reaction of hydrogen with metals for long duration energy storage
A high-speed, high-capacity digital data storage system has been developed for a new balloon-borne gamma-ray telescope. The system incorporates sophisticated, yet easy to use and economical consumer products: the portable video cassette recorder (VCR) and a relatively newer item - the digital audio processor. The in-flight recording system employs eight VCRs and will provide a continuous data storage rate of 1.4 megabits/sec throughout a 40 hour balloon flight. Data storage capacity is 25 gigabytes and power consumption is only 10 watts.
Pumped storage hydropower represents the bulk of the United States' current energy storage capacity: 23 gigawatts (GW) of the 24-GW national total (Denholm et al. 2021). This capacity was largely built between 1960 and 1990. PSH is a mature and proven method of energy storage with competitive round-trip efficiency and long life spans. These qualities make PSH a very attractive potential solution to energy storage needs, particularly for longer-duration storage (8 hours or more); such storage will be crucial to bridge gaps in electricity production as variable wind and solar production continue to comprise an ever-larger portion of the United States' energy portfolio (Cole et al. 2021; Frazier et al. 2021). However, it is unclear how much potential the United States has for the development of new PSH. No new large PSH has been constructed in the United States since the 1990s, and attempts to quantify technical potential capacity from PSH project applications to the Federal Energy Regulatory Commission (FERC) suffer from inconsistent site and cost evaluation methodologies and likely are not representative of all PSH opportunities. This study seeks to better under understand the technical potential for PSH development in the United States by developing a national-scale resource assessment for closed-loop PSH. Individual sites are not modeled in sufficient detail for project-level development, but they do provide valuable insights into potential resource areas across the United States, including the ability to provide estimates for a range of long-term development scenarios.
Energy storage is increasingly being deployed in behind-the-meter use cases, partially in response to falling lithium-ion prices and new utility tariff structures. Utilities are grappling with new tariff design in the presence of distributed energy resources (DER), trying to motivate, fairly price the contribution of, and, in some cases, discourage, certain operation of DER. There are opportunities for energy storage under emerging tariff structures, but utility net load management objectives for storage remain unclear. Diverse tariff structures motivate the use of energy storage to provide one or a combination of: energy arbitrage, energy shifting, solar self-consumption, and import shaving. This paper formulates a linear optimization to demonstrate the optimal storage tariff response, examining customer net load metrics under diverse utility tariff structures, such as time-of-use, net metering, feed-in tariffs, zero export tariffs, and demand charges. A key contribution of this paper is the introduction and examination of a capacity charge as mechanism that can both motivate reductions in both peak import, and exports, along with greater load levelling.
MoO 2 has attracted much recent attention as a high capacity energy storage material. While much of the current work on MoO 2 has been focused on the high capacity four-electron reduction, this reaction is limited to slow charging process due to the large volume change and phase transitions involved. In this study we focus on one-electron insertion reactions and demonstrate that ordered mesoporous thin films of MoO 2 can show signatures of pseudocapacitive charge storage. Mesoporous MoO 2 (mp-MoO 2 ) thin films were treated at different temperatures between 350 and 700 °C to explore the role of crystallinity and nanoscale structure on charging dynamics. The porosity and pore size decreased while the crystallinity and grain size increased as the calcination temperature increased. Materials processed at 600 °C showed the best electrochemical performance due to an optimized combination of high crystallinity and small grain size. These materials could be charged and discharged in 24 s while still achieving a Li + storage capacity of 158 mAh/g. While such thin film systems do not constitute a practical energy storage device, the work here provides structural design parameters for the production of future bulk nanoporous materials.
Coastal or isolated microgrids depend on diesel generators and could benefit from renewable energy resources, especially offshore wind and wave energy. Integrating these resources into microgrids is complicated by their high intermittency, which requires optimal economic dispatch to effectively evaluate. This study considers three coastal or islanded sites, and uses mid-fidelity models of wind and wave energy technologies, and local demand data to solve the optimal economic dispatch problem. An optimal storage sizing method is developed that finds the smallest capacity of energy storage required to meet the microgrid load during each season. The storage capacity decreases by a factor of two at most when adding wave energy converters to a system. Adding wave energy converters to a farm decreases cost by about 30%. Furthermore, the required storage size varies by two to three times from summer to winter. Compared with the state-of-the-art approaches that often overlook realistic offshore renewable energy technology in microgrid economic dispatch and optimal storage sizing, the proposed solution introduced in this study allows for better site selection, microgrid design, converter selection, and storage sizing considerations for isolated microgrids.
As CCS grows beyond isolated first-mover projects, the question of how to identify potential storage sites (prospects) is key to siting projects amidst the constraints of neighboring storage projects, hydrocarbon fields and other considerations. To date, prospects have been defined either by the extent of a buoyant trap or by the predicted maximum extent of the CO 2 or pressure plume. Both approaches have worked, but they may struggle in places like the Gulf of Mexico where complex geologic structure can invalidate simple assumptions of radial plume spread and buoyant traps are commonly unattractive due to numerous legacy well penetrations. Here, we propose identifying prospective storage sites by fetch area (drainage cell) rather than by buoyant closure alone. Doing so offers 1) greater freedom in siting injectors to avoid surface and subsurface constraints, including legacy wells that tend to cluster on structural high; and 2) a coherent flow regime in which buoyancy drives all injected CO 2 toward a common high. This strategy gives space to dissipate injection pressure and minimize the number of legacy wells needing review. It may also offer 1) better injectivity by bringing synclines and associated channel axes into play; and 2) potentially improved capacity by tapping a larger rock volume and taking advantage of migration losses.
The theoretical capacity of a given electrode material is ultimately determined by the number of electrons transferred in each redox center. The design of multi-electron transfer processes could break through the limitation of one–electron transfer and multiply the total capacity, but is difficult to achieve because multiple electron transfer processes are generally thermodynamically and kinetically more complex. In this work, we report the discovery of two-electron transfer in monolayer Ni(OH) 2 nanosheets, which contrasts with the traditional one-electron transfer found in multilayer materials. The first-principles calculations predict that the first oxidation process from Ni 2+ →Ni 3+ occurs easily, whereas the second electron transfer from Ni 3+ →Ni 4+ is strongly hindered in multilayer materials by both the interlayer hydrogen bonds and the domain H structure induced by the Jahn-Teller distortion of the Ni 3+ (t 2g 6 e g 1 ) centered octahedra. In contrast, the second electron transfer can easily occur in monolayers because all H’s are fully exposed. Experimentally, the as-prepared monolayer is found to deliver an exceptional redox capacity of ~ 576 mAh/g, nearly two times the theoretical capacity of one-electron processes. In-situ experiments demonstrate that monolayer Ni(OH) 2 can transfer two electrons and mostly transform to Ni 4+ in the charging process, while bulk Ni(OH) 2 can be partially transformed . Our work reveals a new redox reaction mechanism in atomically thin Ni(OH) 2 nanosheets, and suggests a promising path towards tuning the electron transfer numbers to multiply the capacity of the relevant energy storage materials.
The geological storage of CO 2 in the Earth’s subsurface has the potential to significantly offset greenhouse gas emissions for safe, economical, and acceptable public use. Due to legal advantages and vast resource capacity, offshore CO 2 storage provides an attractive alternative to onshore options. Although offshore Lower Cretaceous reservoirs have a vast expected storage capacity, there is a limited quantitative assessment of the offshore storage resource in the southeastern United States. This work is part of the Southeast Offshore Storage Resource Assessment (SOSRA) project, which presents a high-quality potential geological repository for CO 2 in the Mid- and South Atlantic Planning Areas. This is the first comprehensive investigation and quantitative assessment of CO 2 storage potential for the Lower Cretaceous section of the outer continental shelf that includes the Southeast Georgia Embayment and most of the Blake Plateau. An interpretation of 200,000 km of legacy industrial 2D seismic reflection profiles and geophysical well logs (i.e., TRANSCO 1005-1-1, COST GE-1, and EXXON 564-1) were utilized to create structure and thickness maps for the potential reservoirs and seals. We identified and assessed three target reservoirs isolated by seals based on their effective porosity values. The CO 2 storage capacity of these reservoirs was theoretically calculated using the DOE-NETL equation for saline formations. The prospective storage resources are estimated between 450 and 4700 Mt of CO 2 , with an offshore geological efficiency factor of dolomite between 2% and 3.6% at the formation scale.
Organic electrode materials possess many advantages such as low toxicity, sustainability, and chemical/structural tunability toward high energy density. However, to compete with inorganic-based compounds, crucial aspects such as redox potential, capacity, cycling stability, and electronic conductivity need to be improved. Herein, a comprehensive strategy on the molecular design of small organic electron-acceptor-molecule—hexaazatrianthranylene (HATA) embedded quinone (HATAQ) is reported. By introducing conjugated quinone moieties into the electron-deficient hexaazatriphenylene-derivative core, HATAQ with highly extended π-conjugation can yield extra-high capacity for lithium storage, delivering a capacity of 426 mAh g -1 at 200 mA g -1 (0.4C). At an extremely high rate of 10 A g -1 (19C), a reversible capacity of 209 mAh g -1 corresponding to nearly 85% retention is obtained after 1000 cycles. A unique network of unconventional lock-and-key hydrogen bonds in the solid-state facilitates favorable supramolecular 2D layered arrangement, enhancing cycling stability. To the best of the authors’ knowledge, the capacity and rate capability of HATAQ are found to be the best ever reported for organic small-molecule-based cathodes. Finally, these results together with density functional theory studies provide proof-of-concept that the design strategy is promising for the development of organic electrodes with exceptionally high energy density, rate capability, and cycling stability.
Energy storage is a leading option to enhance the resource adequacy contribution of solar energy. Detailed analysis of the capacity credit of solar energy and energy storage is limited in part due to the data intensive and computationally complex nature of probabilistic resource adequacy assessments. This paper presents a simple algorithm for calculating the capacity credit of energy-limited resources that, due to the low computational and data needs, is well suited to exploratory analysis. Validation against benchmarks based on probabilistic techniques shows that it can yield similar insights. The method is used to evaluate the impact of different solar and storage configurations, particularly with respect to the strategy for coupling storage and solar photovoltaic systems. Furthermore, application of the method to a case study of utilities in Florida, where solar is rapidly growing and demand peaks in the winter and summer, demonstrates that it can improve on rules of thumb used in practice by some utilities. If storage is required to charge only from solar, periods of high demand driven by cold weather events accompanied by lower solar production can result in a capacity credit of solar and storage that is less than the capacity credit of storage alone.
This paper analyzes the impacts of improved day-ahead solar forecasts on costs and dispatch in the solar-rich Southeast U.S. It uses an optimized high-solar, high-storage resource portfolio in which solar generation capacity accounts for 45 % of total installed capacity (34 %–36 % of generation) and energy storage capacity (43 GW) is equivalent to 33 % of peak demand. In a base scenario, improved day-ahead solar forecasts reduce production costs by $\$87$ million per year ($\$0.13$ per MWh load, $2023$$). This level of savings is within the range or lower than earlier studies of solar forecast improvements at lower levels of solar generation (<25 % of total generation). In this study, solar expansion was accompanied by two important sources of flexibility for managing solar forecast error: energy storage and day-ahead solar curtailment. Furthermore, the analysis finds that regional coordination complements day-ahead solar forecast improvements while natural gas commitment flexibility is a substitute for forecast improvements, as the improved solar forecast leads to sub-optimal commitment of thermal units. Day-ahead solar forecast improvements reduce reserves required to manage forecast error by 30 %. Fewer reserves to manage large, infrequent solar forecast errors could be an important benefit of improved solar forecasts.
Thermal energy storage (TES) deployed with concentrating solar power (CSP) has shown value and capabilities in generating dispatchable power. It has attracted significant interest for potential roles in energy storage for various capacities and applications. Energy storage plays an important role in expanding renewable generation and is becoming indispensable in future carbon-free electric power. TES development and deployment provide various possibilities for electric storage and have shown advantages in capacity and flexibility to support renewable integration. In addition, renewable energy integrated with a low-cost TES system can potentially provide a reliable thermal energy supply to displace fossil fuels for broad decarbonization. Varieties of TES technologies and developments breed new areas of growth in TES materials, designs, components, and system configurations, which provide opportunities for substantial cost reduction and performance improvements to meet the technoeconomic challenges in practical applications. This chapter will describe recent progress in thermal energy storage research and development and primarily focus on sensible heat storage and its applications in supplying reliable electricity and industry process heat by integrating with variable renewable energy.
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We propose a solution method for the large-scale stochastic unit commitment (SUC) problem with weekly-dispatched energy storage and significant weather-dependent stochastic generating capacity. Weekly storage facilities that mostly charge during weekends and discharge during weekdays require a weekly scheduling of generating units, which result in a large-scale optimization problem. This SUC problem is formulated as a two-stage stochastic model and we use the conditional value-at-risk as a risk measure. Using a Benders framework, the proposed solution method decomposes the problem into a mixed-integer linear master problem and linear and continuous subproblems. The master problem corresponds to the first-stage decisions throughout the week and includes all the commitment (binary) variables and their corresponding constraints. The subproblems correspond to the actual dispatch of the generating units on a weekly basis. Based on the success of column-and-constraint generation algorithms to solve robust optimization problems, we improve the low communication between the master problem and the subproblems in the standard Benders decomposition by adding primal variables and constraints from the subproblems to the master problem, which provides a better approximation of the recourse function. Furthermore, our computational experiments demonstrate the effectiveness of the proposed decomposition method using an instance of the South Carolina synthetic system with 90 generating units under 40 scenarios.
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The present invention relates to compositions including nano-particles and a nano-structured support matrix, methods of their preparation and applications thereof. The compositions of the present invention are particularly suitable for use as anode material for lithium-ion rechargeable batteries. The nano-structured support matrix can include nanotubes, nanowires, nanorods, and mixtures thereof. The composition can further include a substrate on which the nano-structured support matrix is formed. The substrate can include a current collector material.