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Results for “ALTERNATIVE”

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 361 records · Page 20
All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

Analysis of Alternative Architectures for a 2024 Lunar Sortie

This study focused on performing a broad analysis of lunar architectures to identify key alternatives capable of performing a 2024 human lunar landing mission. The goal of the study was to identify architecture alternatives which exhibit robustness, as measured by launch vehicle payload margin, to absorb the natural growth that occurs during design maturation. The study consisted of up to three element architectures which perform the mission from cis-lunar aggregation, through the surface sortie, and return to cis-lunar space. More than 600,000 data points were evaluated utilizing a novel architecture synthesis framework currently being developed by NASA/MSFC. Key findings from the study indicate that architecture complexity can be reduced by minimizing the number of discrete, unique architecture elements, which in turn translates into reduced design, development, test, and evaluation (DDT&E) complexity. It was identified that heavy lift launch vehicles enable such architectures while also providing significant increases to launch vehicle margin over existing and near-term commercial launch vehicle (CLV) performance expected in the 2024 time frame. Additionally, the study identified storable propellant based lander architectures as leading alternatives in achieving a 2024 human lunar landing by providing reduced technology needs and development schedules.

Architecture Analysis↗
NASA NTRSDate not supplied

NASA Alternate Fecal Canister On-orbit Performance and Applicability to Exploration Missions

NASA developed a collapsible canister for the collection and containment of fecal deposits on long range exploration missions as well as on space stations where mass and volume are of great impact on spacecraft and propulsion designs. Developed as an alternative to the exploration toilet hard-sided canister, the container is a smaller volume for stowage in the unfilled state which allows better use of constrained volume on smaller vehicles for longer missions while still providing the important features of odor and solid/liquid contents containment when in the filled state. A reduction in mass was also achieved for the alternate fecal canister itself, although weight of the lid and contents are common to both the hard-side canister, and the alternate fecal canister. Details of the design, flight build and certification, and technology demonstration on ISS will be discussed. The discussion will include interface requirements and design solutions for use with the Universal Waste Management System (UWMS) as well as future extensibility for other toilet systems.

toilet↗
NASA NTRS2023

Drought-Tolerant Succulent Plants as an Alternative Crop Under Future Global Warming Scenarios in Sub-Saharan Africa

Globally, we are facing an emerging climate crisis, with impacts to be notably felt in semiarid regions across the world. Cultivation of drought-adapted succulent plants has been suggested as a nature-based solution that could: (i) reduce land degradation, (ii) increase agricultural diversification and provide both economic and environmentally sustainable income through derived bioproducts and bioenergy, (iii) help mitigate atmospheric CO 2 emissions and (iv) increase soil sequestration of CO 2 . Identifying where succulents can grow and thrive is an important prerequisite for the advent of a sustainable alternative ‘bioeconomy’. Here, we first explore the viability of succulent cultivation in Africa under future climate projections to 2100 using species distribution modelling to identify climatic parameters of greatest importance and regions of environmental suitability. Minimum temperatures and temperature variability are shown to be key controls in defining the theoretical distribution of three succulent species explored, and under both current and future SSP5 8.5 projections, the conditions required for the growth of at least one of the species are met in most parts of sub-Saharan Africa. These results are supplemented with an analysis of potentially available land for alternative succulent crop cultivation. In total, up to 1.5 billion ha could be considered ecophysiologically suitable and available for succulent cultivation due to projected declines in rangeland biomass and yields of traditional crops. These findings may serve to highlight new opportunities for farmers, governments and key stakeholders in the agriculture and energy sectors to invest in sustainable bioeconomic alternatives that deliver on environmental, social and economic goals.

agriculture↗
DOE OSTI2012

The Prospects of Alternatives to Vapor Compression Technology for Space Cooling and Food Refrigeration Applications

This article identifies and describes five alternative cooling technologies (magnetic, thermionic, thermoacoustic, thermoelectric, and thermotunnel) and qualitatively assesses the prospects of each technology relative to vapor compression for space cooling and food refrigeration applications. Assessment of the alternatives was based on the theoretical maximum % of Carnot efficiency, the current state of development, the best % of Carnot efficiency currently achieved, developmental barriers, and the extent of development activity. The prospect for each alternative was assigned an overall qualitative rating based on the subjective, composite view of the five characteristics.

Brown, Daryl R↗
DOE OSTI2013

Turbo-alternator-compressor design for supercritical high density working fluids

Techniques for generating power are provided. Such techniques involve a thermodynamic system including a housing, a turbine positioned in a turbine cavity of the housing, a compressor positioned in a compressor cavity of the housing, and an alternator positioned in a rotor cavity between the turbine and compressor cavities. The compressor has a high-pressure face facing an inlet of the compressor cavity and a low-pressure face on an opposite side thereof. The alternator has a rotor shaft operatively connected to the turbine and compressor, and is supported in the housing by bearings. Ridges extending from the low-pressure face of the compressor may be provided for balancing thrust across the compressor. Seals may be positioned about the alternator for selectively leaking fluid into the rotor cavity to reduce the temperature therein.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2014

THERMAL EVALUATION OF ALTERNATE SHIPPING CASK FOR GTRI EXPERIMENTS

The Global Threat Reduction Initiative (GTRI) has many experiments yet to be irradiated in support of the High Performance Research Reactor fuels development program. Most of the experiments will be irradiated in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL), then later shipped to the Hot Fuel Examination Facility (HFEF) located at the Materials and Fuels Complex for post irradiation examination. To date, the General Electric (GE)-2000 cask has been used to transport GTRI experiments between these facilities. However, the availability of the GE-2000 cask to support future GTRI experiments is at risk. In addition, the internal cavity of the GE-2000 cask is too short to accommodate shipping the larger GTRI experiments. Therefore, an alternate shipping capability is being pursued. The Battelle Energy Alliance, LLC, Research Reactor (BRR) cask has been determined to be the best alternative to the GE-2000 cask. An evaluation of the thermal performance of the BRR cask is necessary before proceeding with fabrication of the newly designed cask hardware and the development of handling, shipping, and transport procedures. This paper presents the results of the thermal evaluation of the BRR cask loaded with a representative set of fueled and non-fueled experiments. When analyzed with identical payloads, experiment temperatures were found to be lower with the BRR cask than with the GE-2000 cask. From a thermal standpoint, the BRR cask was found to be a suitable alternate to the GE-2000 cask.

42 ENGINEERING↗
DOE OSTI2015

Alternate Lattice Design for Advanced Photon Source Multi-Bend Achromat Upgrade

A 67-pm hybrid-seven-bend achromat (H7BA) lattice is proposed for a futureAdvanced Photon Source (APS)multibend- achromat (MBA) upgrade. This lattice requires use of a swap-out (on-axis) injection scheme. Alternate lattice design work has also been performed to achieve better beam dynamics performance than the nominal APS MBA lattice, in order to allow beam accumulation. One of such alternate H7BA lattice designs, which still targets a very low emittance of 76 pm, is discussed in this paper. With these lattices, existing APS injector complex can be employed without the requirement of a very high charge operation. Studies show that an emittance below 76 pm can be achieved with the employment of reverse bends in an alternate lattice. We discuss the predicted performance and requirements for these lattices and compare them to the nominal lattice.

Sun, Yipeng↗
DOE OSTI2021

AFLEET: ASSESS THE IMPACTS OF CONVENTIONAL AND ALTERNATIVE FUEL VEHICLES

The Alternative Fuel Life-Cycle Environmental and Economic Transportation (AFLEET) tool, developed by researchers at Argonne National Laboratory for the U.S. Department of Energy (DOE) Clean Cities coalition network, estimates the environmental and economic costs and benefits of alternative fuel and advanced vehicles. Using simple inputs, AFLEET lets fleet managers estimate and compare petroleum use, greenhouse gas emissions (GHGs), air pollutant emissions, and cost of ownership for conventional and alternative fuel vehicles (AFVs).

Burnham, Andrew↗
DOE OSTI2013

Targeted Health Assessment for Wastes Contained at the Niagara Falls Storage Site to Guide Planning for Remedial Action Alternatives - 13428

The U.S. Army Corps of Engineers (USACE) is evaluating potential remedial alternatives at the 191-acre Niagara Falls Storage Site (NFSS) in Lewiston, New York, under the Formerly Utilized Sites Remedial Action Program (FUSRAP). The Manhattan Engineer District (MED) and Atomic Energy Commission (AEC) brought radioactive wastes to the site during the 1940's and 1950's, and the U.S. Department of Energy (US DOE) consolidated these wastes into a 10-acre interim waste containment structure (IWCS) in the southwest portion of the site during the 1980's. The USACE is evaluating remedial alternatives for radioactive waste contained within the IWCS at the NFSS under the Feasibility Study phase of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) process. A preliminary evaluation of the IWCS has been conducted to assess potential airborne releases associated with uncovered wastes, particularly during waste excavation, as well as direct exposures to uncovered wastes. Key technical issues for this assessment include: (1) limitations in waste characterization data; (2) representative receptors and exposure routes; (3) estimates of contaminant emissions at an early stage of the evaluation process; (4) consideration of candidate meteorological data and air dispersion modeling approaches; and (5) estimates of health effects from potential exposures to both radionuclides and chemicals that account for recent updates of exposure and toxicity factors. Results of this preliminary health risk assessment indicate if the wastes were uncovered and someone stayed at the IWCS for a number of days to weeks, substantial doses and serious health effects could be incurred. Current controls prevent such exposures, and the controls that would be applied to protect onsite workers during remedial action at the IWCS would also effectively protect the public nearby. This evaluation provides framing context for the upcoming development and detailed evaluation of remedial alternatives for the IWCS. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

Benefits of less intrusive remediation alternatives; A review of case studies in Oak Ridge, Tennessee - 15482

Various alternative cleanup strategies have been utilized at Department of Energy facilities in Oak Ridge, Tennessee to avoid costly and potentially ineffective removal of contaminants in soil and sediments, transportation by truck, and long-term storage in landfills. One such example is a remedial decision in the 1990's to not conduct large-scale removal of PCB-contaminated sediments from a large downstream reservoir, and instead implement sediment disturbance controls and monitoring requirements. Monitoring results suggest the decision was a good one with PCB concentrations in fish decreasing substantially over the last 20 years, presumably due to recent cleaner sediments overlying historical sediment layers. At the East Tennessee Technology Park an innovative remediation strategy was developed to reduce human and ecological risks associated with a PCB-contaminated pond, while also enhancing the site's natural resources. Termed the 'Ecological Management and Enhancement' strategy, this remediation option provided an alternative approach to more conventional pond remediation options like sediment and soil removal, draining and capping, and point source/discharge actions. The basic premise of this option is that ecological management, including fish and wildlife management and vegetation management, can interrupt the contaminant exposure pathways that lead to ecological or human receptors. Recent monitoring results have demonstrated both risk reduction and increased natural resource value. Currently under investigation is the use of watershed management approaches that may help ameliorate mercury methylation and bioaccumulation in East Fork Poplar Creek. There is increased recognition that mercury source reduction alone will not achieve the human health risk target level in fish in the downstream environment, where water chemistry and ecological processes are conducive to mercury methylation. Additionally, significant losses in natural resource values are anticipated if major soil and sediment source removal activities are implemented. The Oak Ridge experience suggests that alternative approaches to the conventional 'muck and truck' options to sediment contamination are worth pursuing in some cases. Taking advantage of natural attenuation processes and/or implementing less intrusive water and ecological manipulations could be especially advantageous at contaminated sites where there are multiple or complex sources that are difficult to remediate, conventional source removal is costly, the contaminant of concern is highly bio-accumulative, or where natural resource values could be preserved or enhanced. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2018

Oxidizer Testing on Alternative Absorbents for Los Alamos National Laboratory - 18656

In the summer of 2016, during glovebox operations in TA-55, cheesecloth, a cellulosic material, was used to clean up a small spill of 9.8 molar nitric acid (oxidizer). Because cellulosic materials and oxidizers are incompatible, this prompted a chemical compatibility evaluation of the waste in TA-55 to determine if this waste was Resource Conservation and Recovery Act (RCRA) ignitable waste (D001) or RCRA reactive waste (D003). After testing and consulting with the Carlsbad Field Office in Carlsbad (CBFO), Los Alamos National Laboratory (LANL) NPI-7 decided to look for alternative absorbents to use in the gloveboxes that would not create an incompatibility issue with an oxidizer. While small spills are infrequent, they do happen and LANL wanted to be proactive and search for a material that would be compatible with an oxidizer. In December 2016, LANL NPI-7 requested LANL-Carlsbad's (LANL-CO) Difficult Waste Team to perform compatibility testing on potential alternative wipes for disposal at the Waste Isolation Pilot Plant (WIPP). The purpose for testing was to meet the Operational Experience Level 3 (OE-3) requirements that states 'any proposed use of organic absorbents or engineered absorbents in combination with potentially oxidizing TRU waste, wet or dry, should be evaluated and approved by the National TRU Program, Carlsbad Field Office' [1]. LANL NPI-7 requested LANL-CO to perform these tests because they were the group that performed all of the oxidizer testing for CBFO for the Basis of Knowledge (BoK) [2]. LANL NPI-7 chose nine fabrics and KMI Zeolite to be tested. The testing in Carlsbad took approximately 2 months to prepare the procedures, test plans and for the procurement of items. The burn rate testing was done in accordance with the requirements discussed in the BoK and approved by the LANL-CO Difficult Waste Team. Each absorbent was tested for 1) capacity limiting tests, 2) verifying the non-oxidizer threshold concentration of the oxidizer and 3) establishing the non-oxidizer concentration based on the experimental results. The effect of rinsing cheesecloth samples that have absorbed an oxidizer was also tested [3]. The burn rate testing provided three potential alternative absorbents (Spilfyter Hazmat Sorbent SM Pads Premium, Kimtech Pure W4 Wipers and Polybenzimidazole (PBI) Staple fiber) that produced a non-oxidizer result as defined by the BoK. Two wipes Spilfyter Hazmat Sorbent SM Pads Premium and Kimtech Pure W4 Wipers were able to absorb the highest concentration of potassium nitrite and still produce a non-oxidizer. TA-55 has used Spilfyter Hazmat Sorbent SM Pads Premium for a number of years in several of the processes and has ordered Kimtech Pure W4 Wipers for use in the facility. PBI fabric passed at 25 wt. % solution. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2024

Navigating the Compliance Reporting Tool: EPAct State and Alternative Provider Fleet Program User Guide

State government and alternative fuel provider fleets covered under the State and Alternative Fuel Provider Fleet Program (Program) established pursuant to the Energy Policy Act of 1992 (EPAct) may use the Compliance Reporting Tool to track and report on several compliance activities. These activities include, but are not limited to, completing Standard Compliance annual reports, Alternative Compliance notices of intent, and exemption requests. Covered fleets can access the Compliance Tool through the Program's website at https://epact.energy.gov/users/sign_in. Covered fleet point of contacts should bookmark the Compliance Reporting Tool for future access. This user guide addresses general tool navigation, including: 1) Logging in to the Tool, 2) Managing Your Point of Contact and Account Information, 3) Managing Fleet Contact Information, 4) Adding New Fleets to Your Account, 5) Reporting for Entities With Multiple Fleets, and 6) Viewing Credit Trades.

ADVANCED PROPULSION SYSTEMS,ENERGY PLANNING, POLIC↗
DOE OSTI2014

Alternative Fuel and Advanced Technology Commercial Lawn Equipment (Brochure)

The U.S. Department of Energy's Clean Cities program produced this guide to help inform the commercial mowing industry about product options and potential benefits. This guide provides information about equipment powered by propane, ethanol, compressed natural gas, biodiesel, and electricity, as well as advanced engine technology. In addition to providing an overview for organizations considering alternative fuel lawn equipment, this guide may also be helpful for organizations that want to consider using additional alternative fueled equipment.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2019

Example Alternative Compliance Annual Report

This document is an example for state and alternative fuel provider fleets regulated by the Energy Policy Act (EPAct) to report how they met their annual requirements using the Alternative Compliance method.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2020

Guidance for Federal Agencies on EPAct 2005 Section 701: Alternative Fuel Use Requirements for Dual-Fueled Vehicles

Section 701 of the Energy Policy Act of 2005 (EPAct 2005) requires Federal agencies to use alternative fuel in dual-fueled vehicles when it is reasonably available and not unreasonably more expensive than gasoline (42 U.S.C. Section 6374(a)(3)(E)). Since 2007, Federal agencies have requested waivers for vehicles from the Section 701 requirements as part of a June data call for the subsequent fiscal year (FY). The U.S. Department of Energy (DOE) Federal Energy Management Program (FEMP) has reviewed those waiver requests and granted or denied them prior to the subsequent FY. At the end of each FY, DOE FEMP has reviewed each Federal agency's covered alternative fuel use and compared it to total fuel use in non-waivered vehicles to determine compliance. This guidance provides two different processes through which DOE will begin evaluating waiver requests for FY 2021 (beginning with the FY 2020 data call): Automated reporting in the Federal Fleet Sustainability Dashboard (FleetDASH), and waiver requests in FAST.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2019

Plant selection initiates alternative successional trajectories in the soil microbial community after disturbance

Because interactions between plants and microbial organisms can influence species diversity and rates of nutrient cycling, how plants shape microbial communities is fundamental to understanding the structure of ecosystems. Despite this, the spatial and temporal scales over which plants influence microbial communities is poorly understood, particularly whether past abiotic or biotic legacies strongly constrain microbial community development. We examined biogeochemical cycling and microbial community structure in a coastal landscape where historical patterns of vegetation transition after a large fire in 1995 are well known, allowing us to account for past abiotic and biotic conditions. We found that alternative states in microbial community structure and ecosystem processes emerged under different plant species, regardless of past conditions. Greenhouse studies further demonstrated that these differences arise from direct plant selection of microbes, with selection stronger in roots compared with soils, especially for bacteria. Correlation of microbial community structure with seedling growth rates was also stronger for fungi compared to bacteria. Despite these effects, minimal overlap between seedling and field microbial communities indicates that the effects of initial plant selection are not stable, rather plant selection initiated alternative successional trajectories after the fire. Using data from a guild where we have abundant natural history information - ectomycorrhizal fungi - we show that greenhouse communities are dominated by ruderal taxa that are also common in the field after the fire, and that these ruderal fungi strongly alter spatial patterns in plant-soil feedback, enabling invasion and transformation of soils previously occupied by heterospecific plants, thus potentially acting as keystone mutualists.

59 BASIC BIOLOGICAL SCIENCES↗