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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 415 records · Page 23
All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

Design of automatic startup and shutdown logic for a Brayton-cycle 2- to 15-kilowatt engine

The NASA Lewis Research Center is conducting a closed-Brayton-cycle power conversion system technology program in which a complete power system (engine) has been designed and demonstrated. This report discusses the design of automatic startup and shutdown logic circuits as a modification to the control system presently used in this demonstration engine. This modification was primarily intended to make starting the engine as simple and safe as possible and to allow the engine to be run unattended. In the modified configuration the engine is started by turning the control console power on and pushing the start button after preheating the gas loop. No other operator action is required to effect a complete startup. Shutdown, if one is required, is also effected by a simple stop button. The automatic startup and shutdown of the engine have been successfully and purposefully demonstrated more than 50 times at the Lewis Research Center during 10,000 hours of unattended operation. The net effect of this modification is an engine that can be safely started and stopped by relatively untrained personnel. The approach lends itself directly to remote unattended operation.

Vrancik, J. E.↗
NASA NTRS1975

Wind power

A historical background on windmill use, the nature of wind, wind conversion system technology and requirements, the economics of wind power and comparisons with alternative systems, data needs, technology development needs, and an implementation plan for wind energy are presented. Considerable progress took place during the 1950's. Most of the modern windmills feature a wind turbine electricity generator located directly at the top of their rotor towers.

Savino, J. M.↗
NASA NTRS1982

Advanced Coal-Based Power Generations

Advanced power-generation systems using coal-derived fuels are evaluated in two-volume report. Report considers fuel cells, combined gas- and steam-turbine cycles, and magnetohydrodynamic (MHD) energy conversion. Presents technological status of each type of system and analyzes performance of each operating on medium-Btu fuel gas, either delivered via pipeline to powerplant or generated by coal-gasification process at plantsite.

Robson, F. L.↗
NASA NTRS1983

Vehicle test report: South Coast Technology electric Volkswagen Rabbit with developmental low-power armature chopper

Dynamometer performance of a South Coast Technology electric conversion of a Volkswagen (VW) Rabbit designated SCT-8 was tested. The SCT-8 vehicle was fitted with a transistorized chopper in the motor armature circuit to supplement the standard motor speed control via field weakening. The armature chopper allowed speed control below the motor base speed. This low speed control was intended to reduce energy loss at idle during stop-and-go traffic; to eliminate the need for using the clutch below base motor speed; and to improve the drivability. Test results indicate an improvement of about 3.5% in battery energy economy for the SAE J227a-D driving cycle and 6% for the C-cycle with only a minor reduction in acceleration performance. A further reduction of about 6% would be possible if provision were made for shutting down field power during the idle phases of the driving cycles. Drivability of the vehicle equipped with the armature chopper was significantly improved compared with the standard SCT Electric Rabbit.

Marte, J. E.↗
NASA NTRS1988

Space power technologies

Information is given in viewgraph form on space power technologies. Energy conversion, the role of nuclear power in space, lunar and Mars bases, and the Pathfinder program are covered.

Sovie, Ronald J.↗
NASA NTRS2004

Remote Sensing of Icy Galilean Moon Surface and Atmospheric Composition Using Low Energy (1 eV-4 keV) Neutral Atom Imaging

We describe a low energy neutral atom imager suitable for composition measurements Europa and other icy Galilean moons in the Jovian magnetosphere. This instrument employs conversion surface technology and is sensitive to either neutrals converted to negative ions, neutrals converted to positive ions and the positive ions themselves depending on the power supply. On a mission such as the Jupiter Icy Moons Orbiter (JIMO), two back-to-back sensors would be flown with separate power supplies fitted to the neutral atom and iodneutral atom sides. This will allow both remote imaging of 1 eV < E < 4 keV neutrals from icy moon surfaces and atmospheres, and in situ measurements of ions at similar energies in the moon ionospheres and Jovian magnetospheric plasma. The instrument provides composition measurements of the neutrals and ions that enter the spectrometer with a mass resolution dependent on the time-of-flight subsystem and capable of resolving molecules. The lower energy neutrals, up to tens of eV, arise from atoms and molecules sputtered off the moon surfaces and out of the moon atmospheres by impacts of more energetic (keV to MeV) ions from the magnetosphere. Direct Simulation Monte Carlo (DSMC) models are used to convert measured neutral abundances to compositional distributions of primary and trace species in the sputtered surfaces and atmospheres. The escaping neutrals can also be detected as ions after photo- or plasma-ionization and pickup. Higher energy, keV neutrals come from charge exchange of magnetospheric ions in the moon atmospheres and provide information on atmospheric structure. At the jovicentric orbits of the icy moons the presence of toroidal gas clouds, as detected at Europa's orbit, provide M e r opportunities to analyze both the composition of neutrals and ions originating from the moon surfaces, and the characteristics of magnetospheric ions interacting with neutral cloud material. Charge exchange of low energy ions near the moons, and directional distributions of the resultant neutrals, allow indirect global mapping of magnetic field structures around the moons. Temporal variation of the magnetic structures can be linked to induced magnetic fields associated with subsurface oceans.

Collier, M. R.↗
NASA NTRS1991

SSTAC/ARTS review of the draft Integrated Technology Plan (ITP). Volume 3: Space power and thermal management

Viewgraphs of briefings from the SSTAC/ARTS review of the draft integrated technology plan on thermal power and thermal management are presented. Topics covered include: space energy conversion research and technology; space photovoltaic energy conversion; chemical energy conversion and storage; thermal energy conversion; power management; thermal management; space nuclear power; high capacity power; surface power and thermal management; space platforms power and thermal management; and project SELENE.

Source record↗
NASA NTRS2014

Solid-State Thermionic Nuclear Power for Megawatt Propulsion, Planetary Surface and Commercial Power Project

Thermionic (TI) power conversion is a promising technology first investigated for power conversion in the 1960's, and of renewed interest due to modern advances in nanotechnology, MEMS, materials and manufacturing. Benefits include high conversion efficiency (20%), static operation with no moving parts and potential for high reliability, greatly reduced plant complexity, and the potential for reduced development costs. Thermionic emission, credited to Edison in 1880, forms the basis of vacuum tubes and much of 20th century electronics. Heat can be converted into electricity when electrons emitted from a hot surface are collected across a small gap. For example, two "small" (6 kWe) Thermionic Space Reactors were flown by the USSR in 1987-88 for ocean radar reconnaissance. Higher powered Nuclear-Thermionic power systems driving Electric Propulsion (Q-thruster, VASIMR, etc.) may offer the breakthrough necessary for human Mars missions of < 1 yr round trip. Power generation on Earth could benefit from simpler, moe economical nuclear plants, and "topping" of more fuel and emission efficient fossil-fuel plants.

George, Jeffrey↗
DOE OSTI2024

Antisolvent‐Mediated Air Quench for High‐Efficiency Air‐Processed Carbon‐Based Planar Perovskite Solar Cells

Perovskite solar cells (PSCs) have becoma a leading low‐cost photovoltaic technology, achieving power conversion efficiencies (PCEs) of up to 26.1%. However, their commercialization is hindered by stability issues and the need for controlled processing environments. Carbon‐electrode‐based PSCs (C‐PSCs) offer enhanced stability and cost‐effectiveness compared to traditional metal‐electrode PSCs, i.e., Au and Ag. However, processing challenges persist, particularly in air conditions where moisture sensitivity poses a significant hurdle. Herein, a novel air processing technique is presented for planar C‐PSCs that incorporates antisolvent vapors, such as chlorobenzene, into a controlled air‐quenching process. This method effectively mitigates moisture‐induced instability, resulting in champion PCEs exceeding 20% and robust stability under ambient conditions. The approach retains 80% of initial efficiency after 30 h of operation at maximum power point without encapsulation. This antisolvent‐mediated air‐quenching technique represents a significant advancement in the scalable production of C‐PSCs, paving the way for future large‐scale deployment.

14 SOLAR ENERGY↗
DOE OSTI2025

Technology Case Study: Techno-Economic and Life Cycle Analysis for Microalgae Conversion Pathways to Fuels and Products

This technology case study report details the cost and sustainability prospects for an emerging feedstock - microalgae - converted to fuels and products via a fractionation and upgrading approach termed combined algae processing (CAP). Detailed techno-economic analysis (TEA) and life cycle analysis (LCA) are conducted for the conversion of farmed algae biomass, with two primary scenarios considering the conversion of either high-compositional-quality biomass enriched in lipids (high-lipid [HL]) or lower-quality biomass enriched in protein (high-protein [HP]). Each scenario employs a different biorefinery configuration tailored towards extracting the maximum value from the given biomass composition. The HL scenario produces fuels and non-isocyanate polyurethane (NIPU) as the primary products, while the HP scenario products fuels and a residual solid coproduct which can be used as a co-feed for producing thermoplastics. The results for the HL scenario were particularly promising, with a minimum fuel selling price (MFSP) of $\$$3.68 per gasoline gallon equivalent (GGE) and fuel GHG emissions translating to 54%-76% reduction compared to petroleum fuels depending on the coproduct handling method used. In contrast, the HP scenario faced more challenges in producing biofuels economically, projecting an MFSP of $\$$7.92/GGE despite significant revenues from the residual algae solids. LCA results for the HP case reflected a 24% reduction potential in biorefinery-level GHG emissions. However, these GHG reductions were primarily associated with the thermoplastic coproduct, which accounted for 93% of all biorefinery outputs by mass. Using a process-level allocation method, carbon intensity results were less promising, indicating a net increase in fuel GHG emissions versus petroleum fuels and highlighting the reliance of this scenario on the thermoplastic coproduct.

09 BIOMASS FUELS↗
DOE OSTI2022

Enabling technologies for the continuous electrically driven conversion of CO 2 and water to multi-carbon products at high current densities

Here, we demonstrate greatly improved conversion of CO 2 using a gas diffusion electrode (GDE) with flowing electrolyte configuration for CO 2 gas delivery in combination with a high surface area nickel phosphide electrocatalyst. This configuration achieves 40–50% selectivity for total carbon products over H 2 formation (HER) at total current densities ranging from 50 to 300 mA cm -2 . We developed a soft-templating method using CTAB detergent micelles for synthesis of phase-pure Ni 2 P, achieving a 260-fold larger surface area (BET) and porous sponge-like morphology that produces stable currents. This catalyst produces mainly one C-product, methylglyoxal (MG, C 3 H 4 O 2 ) with 38–47% overall selectivity, the highest reported selectivity for a 12-electron reduction product. The versatile soft-templating method for electrocatalyst synthesis uses low-temperature (185 °C) that is permissive for incorporation of co-catalysts that are otherwise destroyed by the high temperatures used in traditional solid-state synthesis (SSS). The non-porous Ni 2 P-SSS catalyst produces mainly H 2 at these current densities. Achieving these high currents and C/H selectivity benefits from use of hydrophobic polymers as co-catalyst binders (cationic = Nafion, anionic = PFAEM and neutral = PTFE) to improve CO 2 conversion. PFAEM is the better ionomer for the CO 2 RR at high current density, postulated as due to suppressing CO 2 conversion to inactive bicarbonate. Precipitation of the carbon products as a polycarbonate polymer occurs at high currents.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Supported and coordinated single metal site electrocatalysts

The ever-increasing global environmental and energy crisis issues necessitates technological innovation, especially in the development of renewable energy-related devices, such as electrochemical energy conversion and storage technologies, including fuel cells, water electrolyzers, and CO 2 electrolyzers. Reliable and sustainable energy conversion devices are highly dependent on engineering of electrocatalysts. Furthermore, state-of-the-art electrocatalysts for these electrochemical conversion systems are usually platinum group metal (PGM)-based nanoparticles with high cost, which has sparked intensive research on atomically dispersed single metal site electrocatalysts for decreasing metal loadings and boosting catalytic efficiencies by taking advantage of their inherent electronic effects, quantum size effects, and metal-support interactions. In this review, we first introduced the intrinsic active site identification and stabilization, followed by addressing the mutual metal-support interactions, and most important, their correlations with catalytic properties. Next, the advances in synthetic strategies and characterization techniques for single metal site electrocatalysts are highlighted. Additionally, recent advances in single metal site electrocatalysts designs for applications in electrochemical conversion reactions are also presented. Finally, remaining challenges and a forward-looking perspective on this field of research are provided.

25 ENERGY STORAGE↗
DOE OSTI2020

Lignin-derived electrochemical energy materials and systems

Electrochemical energy storage systems such as supercapacitors, rechargeable batteries and fuel cells have been proven the most effective technologies for energy conversion, storage, and management at different scales. Although a large number of electrochemical energy technologies have been developed in the past and they will continue to be optimized in terms of cost, lifetime, and performance, there is a substantial growing demand for advanced electrochemical energy systems. To deploy these advanced systems, the electrode and electrolyte materials with higher performance, longer life, and lower cost, must be developed. Lignin is the second most abundant natural polymer after cellulose, a byproduct from emerging cellulosic biorefineries, and a waste product from pulp and paper industries. Numerous researches have successfully demonstrated that lignin from different sources can be used as precursors or feedstocks for preparing high-performance electrochemical energy materials and components such as electrodes, electrolytes, membrane separators, and additives. Moreover, techno-economic analyses indicate that it is possible to prepare cost-effective carbons from lignin at engineering scales, compared to current carbon products. These facts suggest that scalable conversion of lignin into high-value energy materials will offer a promising pathway to not only promote the utilization and valorization of lignin but also boost the development of the advanced electrochemical energy systems. This review presents state of the arts of renewable energy materials derived from various lignin and their applications in electrochemical energy systems with emphasis on supercapacitors, rechargeable batteries, and fuel cells. Meanwhile, this article also aims to carve out the critical barriers for lignin-derived high-performance materials for energy applications, intending to identify viable approaches for synthesis of sustainable new energy materials.

09 BIOMASS FUELS↗
DOE OSTI2021

Integration of CO2 Electrolysis with Microbial Syngas Upgrading to Rewire the Carbon Economy

This project has worked towards demonstrating and understanding the conversion of waste CO2 into value added fuels and chemicals. If successful, our proposed technology will incentivize CO2 capture and can add carbon efficiency to biorefineries. We have integrated two conversion technologies to demonstrate a novel approach of combining electrolytic CO2 reduction with biocatalytic CO upgrading. Industrial partners 3M and Dioxide Materials have recently demonstrated electrolytic conversion of CO2 and water to syngas using inexpensive renewable energy. Concurrently, supporting partner Lanzatech has demonstrated industrial scale CO fermentation using steel mill waste CO as a substrate. This presentation will highlight the investment BETO has made to establish a CO2 electrolysis test station and CO fermentation at NREL. We will also discuss the process of increasing the size of the electrolyzers to meet fermentation needs, along with the investigation into the affect CO2 concentration and contaminates have on electrolyzer efficiency, lifetime, and specificity. Additionally, we have begun to examine the downstream impact of electrolyzer off-gas CO:H2 ratios have on the metabolism of C. autoethanologen. Experimental results along input from our industrial partners have led to a baseline techno-economic and life cycle analyses. These results enabled the identification of key cost drivers and carbon intensity of the process. We have used these metrics to identify technology gaps to iteratively inform the process optimization and potential deployment siting to achieve economically viable, sustainable conversion of biopower-derived flue gases to fuels and chemical intermediates.

bioenergy↗
NASA NTRS1977

The NASA thermionic-conversion /TEC-ART/ program

The NASA program for applied research and technology in thermionic energy conversion is described, and the approaches used to obtain the goal of reduced interelectrode losses, improved emitters, and improved collectors are indicated. The current emphasis on out-of-core thermionics allows materials and designs previously prohibited by in-core nucleonics and geometrics. Since high-temperature material effects are important for several components, tungsten, 25%-rhenium technology is a subject of research. Emitter-vaporization, collector-deposition effects were studied, and improvements in metallic-fluid heat pipes are considered. Some required characteristics of electrodes are examined.

Morris, J. F.↗
NASA NTRS1993

Catalysis and biocatalysis program

This final report presents a summary of research activities and accomplishments for the Catalysis and Biocatalysis Program, which was renamed the Biological and Chemical Technologies Research (BCTR) Program, currently of the Advanced Industrial Concepts Division (AICD), Office of Industrial Technologies of the Department of Energy (DOE). The Program was formerly under the Division of Energy Conversion and Utilization Technologies (ECUT) until the DOE reorganization in April, 1990. The goals of the BCTR Program are consistent with the initial ECUT goals, but represent an increased effort toward advances in chemical and biological technology transfer. In addition, the transition reflects a need for the BCTR Program to assume a greater R&D role in chemical catalysis as well as a need to position itself for a more encompassing involvement in a broader range of biological and chemical technology research. The mission of the AICD is to create a balanced Program of high risk, long-term, directed interdisciplinary research and development that will improve energy efficiency and enhance fuel flexibility in the industrial sector. Under AICD, the DOE Catalysis and Biocatalysis Program sponsors research and development in furthering industrial biotechnology applications and promotes the integrated participation of universities, industrial companies, and government research laboratories.

Ingham, J. D.↗
DOE OSTI2020

Sustainable energy and fuels from biomass: a review focusing on hydrothermal biomass processing

Fossil fuels are being replaced with renewable energy resources (biomass and biomass waste, solar, geothermal, wind, etc.) to ensure sustainable development, reduce the dependence on fossil fuels, address environmental challenges including climate change. Today, biomass produces 5 × 10 19 kJ of energy/year, which corresponds to 10% of the annual global energy consumption. Considering the variety of biomass resources, this value is predicted to reach 150 × 10 19 kJ by 2050. Biomass may become even more important for use as an energy resource and chemical raw material in the 21st century. Hydrothermal biomass conversion stands out as a promising and alternative technology. Methods such as traditional gasification and pyrolysis require dry biomass. Hydrothermal techniques have been developed to eliminate the cost and time required for drying biomass. The purpose of this process is to decompose biomass with a high moisture content into small molecules and reduce its oxygen content to obtain liquid fuels or valuable chemicals. Finally, this review presents the current and future state of energy, energy sources, biomass properties and biomass conversion technologies with a focus on hydrothermal technologies.

09 BIOMASS FUELS↗