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All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

LAPIS: Linear Algebra Performance for Intermediate Subprograms

SAND2025-11594O LAPIS (Linear Algebra Performance for Intermediate Subprograms) is a compiler infrastructure for linear algebra that targets both high productivity and performance portability. It is based on the open-source MLIR package from the LLVM project. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.

Kelley, Brian↗
DOE OSTI2024

Economically Viable Intermediate to Long Duration Hydrogen Energy Storage Solutions for Fossil Fueled Assets

This report was prepared as an account of work sponsored by the Office of Fossil Energy and Carbon Management of U.S. Department of Energy under Funding Opportunity Announcement Number DE-FOA-0002332 “Energy Storage for Fossil Power Generation”. The work aimed to explore and advance an innovative hydrogen energy storage system – the synergistically integrated hydrogen energy storage system (SIHES) – that has the following characteristics: • Compatible with existing or new coal and gas fuel electricity generation units, • best suited for intermediate to long duration energy storage, from 12 hours to weeks even months, and • capable of storing energy at the utility scale – hundreds of MWh to GWh energy storage with power output level in tens to hundreds of MW. Preliminary front-end engineering design (Pre-FEED) studies was carried out to develop and refine a site-specific SIHES as peaking power generation units (so named as HyPeaker) as the first market entry point, to demonstrate both the technical feasibility and the economic viability to integrate the HyPeaker “within the fence” of a fossil power plant. This specific site was TVA’s Johnsonville Combustion Turbine Plant. The HyPeaker was designed and engineered to integrate with a 60MW aeroderivative gas turbine unit already available at TVA’s Johnsonville site. This site-specific HyPeaker consists of an alkaline electrolyzer to produce hydrogen from CO 2 free electricity sources, an innovative low-cost high-pressure hydrogen storage system (Big-Ton) and the aero gas turbine to generate electricity using blend of hydrogen and natural gas. A holistic system level technoeconomic analysis tool specific to HyPeaker was developed to optimize the engineering design of the Johnsonville site-specific HyPeaker for cost and performance. The optimal design and specification of the Johnsonville site-specific HyPeaker are the following: • Alkaline electrolyzer: 3MW • Big-Ton storage vessel: 11,000kg H 2 at 3000psi. • 4-stage diaphragm hydrogen compressor: 55kg-H 2 /hr from 150psi to 3000psi. The HyPeaker is designed to provide sufficient hydrogen for 90% continuous operation of the HyPeaker. All major components have design life of 30 years. The capex of HyPeaker is estimated at $\$$7.1M. This included $\$$1.5M for the electrolyzer, $\$$5.6M for the storage vessel and compressor. The cost of aero gas turbine was included as it is already available at the site. Key findings are: • HyPeaker can be designed, manufactured, installed and integrated with the fossil power plants, with sub-systems and components commercially available on the market today, even when it is scaled up to an order of magnitude larger than the one at the Johnsonville site. HyPeaker is a technologically viable solution to cover a wide range of energy storage duration needs, from daily peaking operation to seasonal shifting for fossil fueled assets. • The cost advantage of SCCV based Big-Ton H 2 storage vessel made it possible to “oversize” the H 2 storage subsystem to achieve overall system level cost optimization. The benefits are two-fold. First, it allows to significantly reduce the capacity and cost of electrolyzer by spreading H 2 production over a much longer period of time when the fuel cost for electricity production is low. Second, it allows to balance the hydrogen production and usage shift over weeks to months to meet the peak demands. As such, the capital cost of HyPeaker system using the Big-Ton was less than half of the cost of a system with today’s steel tube based H 2 storage system. The HyPeaker has even better cost advantage Li-ion battery based energy storage system. The estimated capital cost of Li-Ion battery system would be at $\$$38M, under the same projected 20-year electricity generation profile of the Johnsonville site. This is over 5 times more expensive than the HyPeaker system. • Since industry scale energy storage systems do not have 100% energy conversion and storage efficiency, energy storage systems using fossil fuel generated electricity would increase the CO 2 emission. This is particularly the case for HyPeaker due to its low round trip efficiency. Therefore, a more sensible solution would be to the excessive or curtailed electricity from CO 2 emission free sources such as solar farms, wind farms or nuclear power plants, to produce hydrogen, and integrate them with the HyPeaker. Electricity from TVA’s nuclear power plants was used for the Johnsonville HyPeaker. • The economic viability of HyPeaker is expected to be further improved when global supply chains are taken into consideration. For the same Johnsonville site specific HyPeaker, the capex would be reduced to ~$\$$3.6M from ~$\$$7.1M, and the added LCOE is reduced to ~$\$$85/MWh. With the bipartisan Infrastructure Investment and Jobs Act, the cost of domestically produced HyPeaker sub-systems would be at the level of today’s global suppliers. Since the peaking units generally operate at peak usage period, thereby demanding higher price, the projected $\$$85/MWh LCOE would be within the realm of financial viability for utility operators.

08 HYDROGEN↗
DOE OSTI2026

Catalytic Reaction Intermediates Revealed with Femtosecond M-edge XANES (Final Technical Report)

The major goals of this work were to measure the electronic structure of earth-abundant catalysts at key steps in their catalytic cycles using ultrafast UV/Visible, Extreme Ultraviolet, and X-ray spectroscopy. Our central idea was that by using these sophisticated probes, we could uncover hidden reaction mechanisms and provide guidance for catalyst design. A second major goal was the development of Extreme Ultraviolet (XUV) spectroscopy as an accessible, tabletop probe of transition metal electronic structure. Spectra in this 30-100 eV energy range probe 3d→3p transitions in 3d metals and 5p/4f→5d transitions in 5d metals, and share the oxidation state, spin state, and ligand field specificity of hard X-ray spectroscopy. The Vura-Weis group previously established the basic utility of this technique for measuring the excited-state cascades of transition metal chromophores, and in this grant we intended to extend its scope to catalytic intermediates.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Preparation and Characterization of Materials for Low- to Intermediate-Temperature CO2 Adsorption

Global carbon dioxide emissions are rising and the use of fossil fuels in several sectors are the leading causes. As global population and economies continue to grow significantly, the most practical method of lowering such emissions is to capture CO2. Although other technologies are more developed, adsorption is very promising and has attracted much attention. To ensure this technology’s success, it is essential to have suitable CO2 adsorbent materials. In this work, several new hydrotalcites (HTs) with different initial concentrations of ion precursors were prepared for the first time by the co-precipitation method—it was possible to verify that the ion concentrations influence the characteristics of the materials. The prepared HTs were characterized by thermogravimetric analysis (TG), X-Ray diffraction (XRD), surface area measurements and temperature-programmed desorption of CO2 (TPD-CO2) to relate their CO2 capture capacity to their physicochemical properties; the CO2 adsorption equilibrium isotherms were determined at 35 and 300 °C for the prepared samples, as well as for some commercial materials: magnesium oxide, calcium oxide, aluminium oxide and Zeolite 13X. After determining which materials present the best CO2 adsorption capacity, these were submitted to adsorption-desorption cycles to study their stability. The main objective of the work was to prepare and study different CO2 adsorbents for processes that are carried out at low and intermediate temperatures. From the experimental results, it was possible to conclude that the Zeolite 13X showed the best capacity at 35 °C, 3.38 mmol·g−1 (@ pCO2 = 1 bar), and a prepared calcined HT (c-HT2) was the best at 300 °C, 0.97 mmol·g−1 (@ pCO2 = 1 bar). Moreover, it seems there is an optimum initial concentration of the ions’ solutions for the tested HTs, which depends on the final application—c-HT1 showed a better capacity at 35 °C and c-HT2 at 300 °C. From the adsorption-desorption cycles—performed at 35 and 300 °C with the best materials using a magnetic suspension microbalance at 1 bar of CO2 partial pressure —, a working cyclic capacity of 2.69 mmol∙g−1 was achieved by the Zeolite at 35 °C; in turn, c-HT2 showed a working cyclic capacity of 0.79 mmol∙g−1 at 300 °C.

Figueiredo, Anabela↗
DOE OSTI2024

Stellar Mergers or Truly Young? Intermediate-age Stars on Highly Radial Orbits in the Milky Way’s Stellar Halo

Reconstructing the mass assembly history of the Milky Way relies on obtaining detailed measurements of the properties of many stars in the galaxy, especially in the stellar halo. One of the most constraining quantities is stellar age, as it can shed light on the accretion time and quenching of star formation in merging satellites. However, obtaining reliable age estimates for large samples of halo stars is difficult. We report published ages of 120 subgiant halo stars with highly radial orbits that likely belong to the debris of the Gaia-Enceladus/Sausage (GES) galaxy. The majority of these halo stars are old, with an age distribution characterized by a median of 11.6 Gyr and a 16th (84th) percentile of 10.5 (12.7) Gyr. However, the distribution is skewed, with a tail of younger stars that span ages down to ~6–9 Gyr. All highly radial halo stars have chemical and kinematic/orbital quantities that associate them with the GES debris. Initial results suggest that these intermediate-age stars are not a product of mass transfer and/or stellar mergers, which can bias their age determination low. If this conclusion is upheld by upcoming spectrophotometric studies, then the presence of these stars will pose an important challenge for constraining the properties of the GES merger and the accretion history of the galaxy.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2025

Hadronic vacuum polarization for the muon g - 2 from lattice QCD: Complete short and intermediate windows

We present complete results for the hadronic vacuum polarization (HVP) contribution to the muon anomalous magnetic moment a μ in the short- and intermediate-distance window regions, which account for roughly 10% and 35% of the total HVP contribution to a μ , respectively. In particular, we perform lattice-QCD calculations for the isospin-symmetric connected and disconnected contributions, as well as corrections due to strong-isospin breaking. For the short-distance window observables, we investigate the so-called log-enhancement effects as well as the significant oscillations associated with staggered quarks in this region. For the dominant, isospin-symmetric light-quark-connected contribution, we obtain a μ l l , SD ( conn ) = 48.139 ( 11 ) stat ( 91 ) syst [ 92 ] total × 10 - 10 and a μ l l , W ( conn ) = 206.90 ( 14 ) stat ( 61 ) syst [ 63 ] total × 10 - 10 . We use Bayesian model averaging to fully estimate the covariance matrix between the individual contributions. Our determinations of the complete window contributions are a μ SD = 69.05 ( 1 ) stat ( 21 ) syst [ 21 ] total × 10 - 10 and a μ W = 236.45 ( 17 ) stat ( 83 ) syst [ 85 ] total × 10 - 10 . This work is part of our ongoing effort to compute all contributions to HVP with an overall uncertainty at the few-permille level.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
NASA NTRS1958

A Feasibility Study of the Flare-Cylinder Configuration as a Reentry Body Shape for an Intermediate Range Ballistic Missile

A study has been made of a flare-cylinder configuration to investigate its feasibility as a reentry body of an intermediate range ballistic missile. Factors considered were heating, weight, stability, and impact velocity. A series of trajectories covering the possible range of weight-drag ratios were computed for simple truncated nose shapes of varying pointedness, and hence varying weight-drag ratios. Four trajectories were chosen for detailed temperature computation from among those trajectories estimated to be possible. Temperature calculations were made for both "conventional" (for example, copper, Inconel, and stainless steel) and "unconventional" (for example, beryllium and graphite) materials. Results of the computations showed that an impact Mach number of 0.5 was readily obtainable for a body constructed from conventional materials. A substantial increase in subsonic impact velocity above a Mach number of 0.5 was possible without exceeding material temperature limits. A weight saving of up to 134 pounds out of 822 was possible with unconventional materials. This saving represents 78 percent of the structural weight. Supersonic impact would require construction of the body from unconventional materials but appeared to be well within the range of attainability.

Garland, B. J.↗
NASA NTRS1966

Intermediate rotating ring improves reliability of dynamic shaft seal

Intermediate rotating ring improves the reliability of dynamic shaft seals whose rubbing surfaces wear down rapidly at high shaft speeds. The rotating ring is placed between the rotating shaft sealing surfaces and the stationary surface, and driven at one-half the shaft speed.

Mesny, P. R.↗