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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 19 records

Coordination of Advanced Solar Observatory (ASO) Science Working Group (SWG) for the study of instrument accommodation and operational requirements on space station

The objectives are to coordinate the activities of the Science Working Group (SWG) of the Advanced Solar Observatory (ASO) for the study of instruments accommodation and operation requirements on board space station. In order to facilitate the progress of the objective, two conferences were organized, together with two small group discussions.

Wu, S. T.↗

SPHERES Synchronized, Position, Hold, Engage, Reorient, Experimental Satellites: SPHERES Working Group (SWG) Quarterly Meeting

SPHERES Working Group (SWG) Quarterly meeting. Membership includes MIT, FIT, AFS, DARPA, CASIS, SJSU, and NASA (HQ, KSC, JSC, MSFC, and ARC). Face-to-Face, twice a year. Next Face-to-Face will be scheduled in Feb. 2017 at NASA Ames. Purpose: Information sharing across the SPHERES community. Program office shares National Lab Facility availability. Status of resources (batteries, CO2 tanks, etc.), Overall Calendar (scheduled Test Sessions, upmassreturn), and Updates on new PD, Investigations, and ISS infrastructure.Provide the SPHERES community (PD, investigators, etc.) with up-to-date information to determine opportunities to use the NL Facility. Discuss proposed changes updates to SPHERES Nat Lab which may be required to support a specific activity or research. Discuss specific support requests made to the ISS Office.

Jose V Benavides↗

Cost-Benefit Analysis For Indonesia Building Sector: Whole-Building Cooling Solutions

The Net Zero World (NZW) Initiative Collaborative Work Program with the Government of Indonesia (GoI) includes technical assistance and investment mobilization facilitation to accelerate deployment of energy efficiency technologies and solutions for the building sector. A February 2023 U.S.–Indonesia Joint Workshop on Decarbonizing the Building Sector yielded a NZW Indonesia Building Decarbonization Working Group (NZW IBDWG) with four sub-working groups (SWG): SWG-A National Center, SWG-B Capacity Building, SWG-C Investment and Financing, and SWG-D Pilot Projects. Technical analysis of whole-building cooling solutions for tropical climates of Indonesia was conducted by SWG-A to quantify energy savings, carbon dioxide reductions, and comfort improvements offered by 12 passive or low-energy cooling strategies: ceiling fans with and without thermostat setbacks; cool roofs; cool walls; exterior awnings; exterior shades; interior shades; insulated roofs; insulated walls; low-e windows; solar window films; and natural ventilation. Leveraging the results from SWG-A, cost-benefit analysis (CBA) was conducted by SWG-C to assess the consumer and national costs and impacts associated with these 12 cooling solutions. The evaluation involved estimating life-cycle costs (LCC), payback period (PBP), net present values (NPV), annual electricity burden change for low-income households, and reduced national annual power-sector generation demand by 2030, 2040, 2050, and 2060. This evaluation can help guide Indonesia’s Just Energy Transition Partnership (JETP) investments in policies and programs to advance research, development, deployment, and commercial adoption (RDDCA) of efficient residential building sector cooling technologies and solutions in Indonesia. Four key energy conservation measures (ECM) have been identified to reduce air-conditioning (AC) energy demand in single-family housing in Indonesia: ceiling fan with temperature setback (to 28.1 °Celcius from 25 °C); insulated walls; insulated roof; and cool roof. This study found that low-income households with AC installations in Indonesia currently face a high energy cost burden of approximately 10%. However, by implementing a ceiling fan with temperature setback, this burden could decrease to 2.5% today and further reduce to 1.3% by the year 2060. The PBP for a ceiling fan with temperature setback is one year, indicating one of the lowest LCC and best NPV. In the planned upcoming phase of CBA, a series of building cooling improvement scenarios can be further defined, incorporating more than one ECM in combination with socio-economic factors evaluated in the initial CBA phase. Additionally, the analysis of ECM effects in multifamily housing can be expanded. This broader national analysis aims to encompass a holistic and comprehensive system-level perspective, including factors such as avoided power sector infrastructure investments, domestic job creation, domestic manufacturing job creation, and gross domestic product (GDP) growth.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Corn and Switchgrass Derived Sustainable Aviation Fuel Carbon Intensity

The production and use of sustainable aviation fuel (SAF) could lower aviation's carbon footprint. Feedstock agricultural management can optimize—or potentially determine—SAF sustainability and profitability, but long-term SAF feedstock comparisons are limited. Life cycle assessments (LCA) are commonly used to estimate the carbon intensity of producing SAF from emerging feedstocks due to the limited availability of long-term, primary field data. We quantified the agricultural phase and well-to-wake (WTWa) carbon intensities of producing SAF from no-till, continuous corn (Zea mays L.) under 120 kg N ha−1 year−1 (120 N corn) and switchgrass (Panicum virgatum L.) under 60 or 120 kg N ha−1 year−1 (60 N and 120 N SWG, respectively) via LCAs based on measured data from a long-term (1998-present) field experiment on marginally productive cropland located in Eastern NE, USA. Measured data included crop productivity, long-term changes in soil organic carbon (SOC) stocks (0–150 cm), annual soil N2O emissions, and field management practices. Both 120 N corn (2078 L ha−1) and 120 N SWG (1752 L ha−1) produced more SAF than 60 N SWG (1229 L ha−1) (p < 0.0001). However, making SAF from corn had greater life cycle GHG emissions (i.e., WTWa carbon intensity) than making SAF from 120 N and 60 N SWG (61.5 > −14.5 and −27.5 g CO2e MJ−1 SAF, respectively; p = 0.0007), primarily due to SOC accrual during crop production. Here, we demonstrate that agricultural management (e.g., crop type, fertilizer use) can determine the sustainably and productivity of producing SAF by using long-term, measured field data in LCAs.

carbon intensity↗

Broadband integrated polarization splitter and rotator using subwavelength grating claddings

We present a broadband integrated photonic polarization splitter and rotator (PSR) using adiabatically tapered coupled waveguides with subwavelength grating (SWG) claddings. The PSR adiabatically rotates and splits the fundamental transverse-magnetic (TM 0 ) input to the fundamental transverse-electric (TE 0 ) mode in the coupler waveguide, while passing the TE 0 input through the same waveguide. The SWGs work as an anisotropic metamaterial and facilitate modal conversions, making the PSR efficient and broadband. We rigorously present our design approaches in each section and show the SWG effect by comparing with and without the SWG claddings. The coupling coefficients in each segment explicitly show a stronger coupling effect when the SWGs are included, confirmed by the coupled-mode theory simulations. The full numerical simulation shows that the SWG-PSR operates at 1500–1750 nm (≈250 nm) wavelengths with an extinction ratio larger than 20 dB, confirmed by the experiment for the 1490–1590 nm range. The insertion losses are below 1.3 dB. Since our PSR is designed based on adiabatical mode evolution, the proposed PSR is expected to be tolerant to fabrication variations and should be broadly applicable to polarization management in photonic integrated circuits.

47 OTHER INSTRUMENTATION↗

Phase II Cost-Benefit Analysis: Economic Impact Assessment For Indonesia Building Sector Whole-Building Cooling Solutions

The Net Zero World (NZW) Initiative Collaborative Work Program with the Government of Indonesia (GoI) includes technical assistance and investment mobilization facilitation to accelerate deployment of energy efficiency technologies and solutions for the building sector. A February 2023 US–Indonesia Joint Workshop on Decarbonizing the Building Sector yielded a NZW Indonesia Building Decarbonization Working Group (NZW IBDWG) with four sub working groups (SWGs): SWG-A National Center, SWG-B Capacity Building, SWG-C Investment and Financing, and SWG-D Pilot Projects.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Chairmanship of the Neptune/Pluto outer planets science working group

The Outer Planets Science Working Group (OPSWG) is the NASA Solar System Exploration Division (SSED) scientific steering committee for the Outer Solar System missions. OPSWG consists of 19 members and is chaired by Dr. S. Alan Stern. This proposal summarizes the FY93 activities of OPSWG, describes a set of objectives for OPSWG in FY94, and outlines the SWG's activities for FY95. As chair of OPSWG, Dr. Stern will be responsible for: organizing priorities, setting agendas, conducting meetings of the Outer Planets SWG; reporting the results of OPSWG's work to SSED; supporting those activities relating to OPSWG work, such as briefings to the SSES, COMPLEX, and OSS; supporting the JPL/SAIC Pluto study team; and other tasks requested by SSED. As the Scientific Working Group (SWG) for Jupiter and the planets beyond, OPSWG is the SSED SWG chartered to study and develop mission plans for all missions to the giant planets, Pluto, and other distant objects in the remote outer solar system. In that role, OPSWG is responsible for: defining and prioritizing scientific objectives for missions to these bodies; defining and documenting the scientific goals and rationale behind such missions; defining and prioritizing the datasets to be obtained in these missions; defining and prioritizing measurement objectives for these missions; defining and documenting the scientific rationale for strawman instrument payloads; defining and prioritizing the scientific requirements for orbital tour and flyby encounter trajectories; defining cruise science opportunities plan; providing technical feedback to JPL and SSED on the scientific capabilities of engineering studies for these missions; providing documentation to SSED concerning the scientific goals, objectives, and rationale for the mission; interfacing with other SSED and OSS committees at the request of SSED's Director or those committee chairs; providing input to SSED concerning the structure and content of the Announcement of Opportunity for payload and scientific team selection for such missions; and providing other technical or programmatic inputs concerning outer solar system missions at the request of the Director of SSED.

Stern, S. Alan↗

Anisotropic leaky-like perturbation with subwavelength gratings enables zero crosstalk

Abstract Electromagnetic coupling via an evanescent field or radiative wave is a primary characteristic of light, allowing optical signal/power transfer in a photonic circuit but limiting integration density. A leaky mode, which combines both evanescent field and radiative wave, causes stronger coupling and is thus considered not ideal for dense integration. Here we show that a leaky oscillation with anisotropic perturbation rather can achieve completely zero crosstalk realized by subwavelength grating (SWG) metamaterials. The oscillating fields in the SWGs enable coupling coefficients in each direction to counteract each other, resulting in completely zero crosstalk. We experimentally demonstrate such an extraordinarily low coupling between closely spaced identical leaky SWG waveguides, suppressing the crosstalk by ≈40 dB compared to conventional strip waveguides, corresponding to ≈100 times longer coupling length. This leaky-SWG suppresses the crosstalk of transverse–magnetic (TM) mode, which is challenging due to its low confinement, and marks a novel approach in electromagnetic coupling applicable to other spectral regimes and generic devices.

42 ENGINEERING↗

Topics and Considerations for Developing State Geothermal Regulations

The intent of this document is to provide guidance to states for developing geothermal regulations that would be inclusive of all geothermal technologies (e.g., conventional and non-conventional power production and direct-use applications) with applicability in all states. As part of this project, the NREL project team reviewed and catalogued existing state and federal geothermal regulations, compiled best practices from geothermal and other extractive industries, and established a Geothermal Regulatory Stakeholder Working Group (SWG) to advise and review the geothermal regulatory guidance. The SWG met approximately monthly over the course of one year to review and discuss specific topics as relevant to this geothermal regulatory guidance. This report is broken into five main sections, which were identified in coordination with the SWG as the main topics for inclusion. Within these sections, a list of considerations within each category were identified and, in some cases, relevant examples from existing state and federal geothermal regulations are included to further illustrate the proposed considerations. This report includes the following topics: geothermal resource definition; leasing process; exploration approval process; drilling/wellfield development approval process; and underground injection control process.

15 GEOTHERMAL ENERGY↗

Triaxial Shear Tests on Simulated Sierra White Fault Gouge & Borehole Simulation in Sierra White Gouge

Laboratory shear tests were conducted on pulverized Sierra White granite (SWG) to investigate slip mechanisms in naturally occurring faults. Synthetic fault geometries were constructed by sandwiching fine grained SWG powder in between steel forcing blocks. For dry experiments, ~3.5 g of SWG powder was poured onto the face of the lower steel forcing block and leveled. For saturated experiments, enough fluid was added to the ~3.5 g of Sierra White granite powder to form a slurry. This slurry was applied to the lower forcing block and leveled. Inclined forcing blocks with 25.4 mm diameter and 35° faces, which were machined from ground steel rods with fine teeth on the faces, help to hold the gouge in place and prevent delamination at the interface. The top forcing block had a 2.03 mm centered hole to allow pore fluid access to the gouge. A fine steel mesh prevented back flow of the gouge into pore fluid lines. Samples were isolated from the confining medium using three layers of heat shrink polyolefin, as shown in Figure 1. The outer layer was shrunk over the o-rings on the end caps to form an impermeable seal, which was reinforced with steel tie wires on both sides of the o-rings. Hardened steel spacers and copper shim stock was placed between the steel forcing blocks and the end caps to preserve the parallelism of the Hastelloy wetted parts. For dry samples, the end caps were plugged, while the end caps for the saturated samples were connected to pore lines.

58 GEOSCIENCES↗

Research in Support of the Use of Rankine Cycle Energy Conversion Systems for Space Power and Propulsion

This is the report of a Scientific Working Group (SWG) formed by NASA to determine the feasibility of using a liquid metal cooled nuclear reactor and Rankine energy conversion cycle for dual purpose power and propulsion in space. This is a high level technical report which is intended for use by NASA management in program planning. The SWG was composed of a team of specialists in nuclear energy and multiphase flow and heat transfer technology from academia, national laboratories, NASA and industry. The SWG has identified the key technology issues that need to be addressed and have recommended an integrated short term (approx. 2 years) and a long term (approx. 10 year) research and development (R&D) program to qualify a Rankine cycle power plant for use in space. This research is ultimately intended to give NASA and its contractors the ability to reliably predict both steady and transient multiphase flow and heat transfer phenomena at reduced gravity, so they can analyze and optimize designs and scale-up experimental data on Rankine cycle components and systems. In addition, some of these results should also be useful for the analysis and design of various multiphase life support and thermal management systems being considered by NASA.

Lahey, Richard T., Jr.↗

Terrestrial Planet Finder Interferometer Science Working Group Report

Over the past two years, the focus of the project for the interferometric version of the Terrestrial Planet Finder(TPF-I) has been on the development of the scientific rational for the mission, the assessment of TPF-I architectures, the laboratory demonstration of key technologies, and the development of a detailed technology roadmap. The Science Working Group (SWG), in conjunction with European colleagues working on the European Space Agency's (ESA's) Darwin project, has reaffirmed the goals of TPF-I as part of a broad vision for the detection and characterization of Earth-like planets orbiting nearby stars and for the search for life on those planets. The SWG also helped to assess the performance of different interferometric configurations for TPF-I/Darwin. Building on earlier SWG reports, this document restates the scientific case for TPF-I, assesses suitable target stars and relevant wavelengths for observation, discusses dramatic new capabilities for general astrophysical observations, and summarizes how Spitzer has improved our knowledge of the incidence of zodiacal emission on the search for planets. This document discusses in some detail on laboratory advances in interferometric nulling and formation flying. Laboratory experiments have now achieved stable narrow- and broad-band nulling the levels of 10-6 and 2.0x10-5, respectively. A testbed has demonstrated formation flying using two realistic spacecraft mockups. With a suitably funded program of technology development, as summarized herein and described in more detail in the Technology Plan for the Terrestrial Planet Finder Interferometer (2005), the National Aeronautics and Space Administration (NASA) and ESA would be able to start within the coming decade a full-scale TPF-I/Darwin mission capable of finding Earths orbiting more than 150 nearby stars, or a scaled back interferometer capable of studying more than 30 stars. Finding evidence for life on just one of those planets would revolutionize our understanding of our place in the cosmos.

interferometers↗

Assessing the Needs for Space Reactor Standards

A U.S. governmental interagency space reactor standards working group (SWG) was convened to address the limited availability of voluntary consensus standards currently in place specifically for space nuclear reactor design and safety. The SWG focused on reviewing existing standards, assessing agency needs, specifying gaps that could be addressed by new standards, and prioritizing those gaps through consensus group deliberations. The SWG identified a series of findings and recommendations relative to the development of space reactor standards, including moving three specific high-priority gap items to be pursued through a consensus standards development process: Safety and Risk Analysis Methods for Space Reactors, Testing Requirements for Space Reactors, including Facility Requirements, and Safe Operating Practices for Space Reactors.

Andrew Klein↗

Report of the Interagency Space Reactor Standards Working Group

A U.S. governmental interagency space reactor standards working group (SWG) was convened in April 2021 with a memo from the NASA Chief Engineer to address the limited standards and regulations in place specifically for space reactor design and safety. The convening memo requested support from the Standards Executives of six other federal agencies. The Standards Executives agreed to support a 6-month study to assess the need for consensus standards and identified SWG representatives from each agency. This report summarizes the SWG’s study, their findings, and their recommendations.

Space Reactor Standards Working Group↗

Topics and Considerations for Developing State Geothermal Regulations

The intent of this document is to provide guidance to states for developing geothermal regulations that would be inclusive of all geothermal technologies (e.g., conventional and non-conventional power production and direct-use applications) with applicability in all states. As part of this project, the NREL project team reviewed and catalogued existing state and federal geothermal regulations, compiled best practices from geothermal and other extractive industries, and established a Geothermal Regulatory Stakeholder Working Group (SWG) to advise and review the geothermal regulatory guidance. The SWG met approximately monthly over the course of one year to review and discuss specific topics as relevant to this geothermal regulatory guidance. This report is broken into five main sections, which were identified in coordination with the SWG as the main topics for inclusion. Within these sections, a list of considerations within each category were identified and, in some cases, relevant examples from existing state and federal geothermal regulations are included to further illustrate the proposed considerations. This report includes the following topics: 1) Geothermal Resource Definition; 2) Leasing process; 3) Exploration approval process; 4) Drilling/wellfield development approval process; 5) Underground injection control process In addition, a list of 'key considerations' summarized from this report are included below. This list is not meant to be exhaustive as each state's regulatory landscape is unique, rather these are meant to be concepts that can be considered when developing and/or updating existing geothermal regulations.

drilling↗

Near-Term Effects of Perennial Grasses on Soil Carbon and Nitrogen in Eastern Nebraska

Incorporating native perennial grasses adjacent to annual row crop systems managed on marginal lands can increase system resiliency by diversifying food and energy production. This study evaluated (1) soil organic C (SOC) and total N stocks (TN) under warm-season grass (WSG) monocultures and a low diversity mixture compared to an adjacent no-till continuous-corn system, and (2) WSG total above-ground biomass (AGB) in response to two levels of N fertilization from 2012 to 2017 in eastern Nebraska, USA. The WSG treatments consisted of (1) switchgrass (SWG), (2) big bluestem (BGB), and (3) low-diversity grass mixture (LDM; big bluestem, Indiangrass, and sideoat grama). Soils were sampled at fixed depth increments (0–120 cm) in the WSG plots and in the adjacent corn experiment in 2012 and 2017. Soil stocks (Mg ha−1) of SOC and TN were calculated on an equivalent soil mass (ESM) basis and compared within the three WSG treatments as well as between experiments (corn compared to the mean of all WSGs). Soil organic C and TN stocks within soil layers and cumulative stocks responded to the main effect of WSG (PWSG < 0.05) but were no different when comparing the WSGs to corn (Pexpt = NS). Both SOC/TN stocks and cumulative stocks were generally greater in the LDM compared to the BGB. Neither SOC nor TN changed over time under either the WSGs or corn. Warm-season grass AGB responded to a three-way interaction of year, N rate, and WSG (p = 0.0007). Decreases in AGB over time were significant across WSGs and N levels except for SWG at 56 kg N ha−1 and LDM at 112 kg N ha−1. Above-ground biomass was generally greater in the LDM after the first harvest year (2013). Results suggest that incorporating WSGs into marginal cropland can maintain SOC and TN stocks while providing a significant source of biomass to be used in energy production or in integrated livestock systems.

Ramirez, II, Salvador (ORCID:000000030152153X)↗