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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 91 records · Page 5
All sourcesNASA NTRSDOE OSTI
DOE OSTI2013

Modeling of GE Appliances: Final Presentation

The Energy Information Administration (EIA) estimates that electricity use will increase by more than 30 percent by 2035, and that residential electricity usage will increase by 23 percent. During this time, peak electricity demand is expected grow at an even greater rate, requiring significant investment in system capacity. In addition, increased penetration of intermittent renewable resources will increase system variability, requiring additional resources to mitigate the variability associated with generator output. Widespread adoption of demand response (DR) enabled appliances, thermostats, and other demand-side resources can result in significant reduction to peak electrical demand and provide potential grid stabilization benefits. The key to adoption is to provide this resource at a cost commensurate with traditional grid capabilities, and to appropriately share both the costs and the benefits between the consumer and the service provider (i.e., the utility). However, the business model for investing in demand-side resources cannot be determined without an estimation of the possible technical benefits and how those benefits translate to monetary value in current electrical market structures. GE Appliances has developed a line of appliances that will have the capability of offering several levels of demand reduction actions based on information received from the utility grid, often in the form of price or grid status. However due to a number of factors, including the number of DR-enabled appliances available at any given time, the reduction of diversity factor due to the synchronizing control signal, and the percentage of consumers who may override the utility signal, it can be difficult to predict the aggregate response of a large number of residences. The effects of these behaviors have been modeled and simulated in the Pacific Northwest National Laboratory (PNNL) developed open-source software, GridLAB-D™, including evaluation of appliance controls, improvement to current algorithms, and development of aggregate control methodologies. The results of these simulations provide an estimation of the possible technical benefits (e.g., peak load reduction) attributable to smart appliances, but do not describe the monetary value of these services. This report is the final in a series of three reports funded by U.S. Department of Energy Office of Electricity Delivery and Energy Reliability (DOE-OE) in collaboration with GE Appliances’ through a Cooperative Research and Development Agreement (CRADA) to describe the potential of GE Appliances’ DR-enabled appliances to provide benefits to the utility grid.

Demand Response↗
DOE OSTI2026

Carbon Tetrachloride Degradation Results for 200-ZP-1 Operable Unit

Carbon tetrachloride (CT) contamination in the 200-ZP-1 Operable Unit (OU) at the Hanford Site originated from large-volume discharges to the subsurface during plutonium production operations between 1955 and 1973. Contamination migrated through more than 70 meters of unsaturated sediment to reach the underlying unconfined aquifer, where it persists as a large and complex groundwater plume. The 200-ZP-1 OU Record of Decision (ROD) requires that groundwater CT concentrations be reduced to 3.4 µg/L within 125 years. Current groundwater modeling projections estimate that the existing pump-and-treat, even when combined with monitored natural attenuation (specifically hydrolysis), will not achieve this target within the designated timeframe. A fundamental contributor to this shortfall is the extremely slow rate of CT hydrolysis under Hanford aquifer conditions, which has been estimated to have a half-life of 630 years. If faster-acting biotic and abiotic degradation processes are operating within the aquifer, their contribution to CT mass reduction could have a meaningful impact. However, site-specific measurements of these processes and their rates have not previously been performed. This report documents the results of a two-phase laboratory investigation designed to characterize and quantify the capacity of site-specific 200-ZP-1 OU sediments and groundwater to support natural attenuation of CT through biotic and abiotic pathways. In this context, degradation capacity is defined as the intrinsic potential of the subsurface matrix to transform CT under optimized, controlled conditions. System capacity is evaluated in two ways: (1) as rate-limited capacity, which establishes the maximum kinetic velocity of CT transformation and is measured using half-lives and first order rate constants; and (2) as mass limited capacity, which defines the total contaminant mass the batch experimental system can degrade before reactants are exhausted, representing the maximum amount of contaminant the microbial community and reactive mineral phases can transform under the experimental conditions.

abiotic degradation↗
DOE OSTI2016

Methods to Determine Recommended Feeder-Wide Advanced Inverter Settings for Improving Distribution System Performance

This paper describes methods that a distribution engineer could use to determine advanced inverter settings to improve distribution system performance. These settings are for fixed power factor, volt-var, and volt-watt functionality. Depending on the level of detail that is desired, different methods are proposed to determine single settings applicable for all advanced inverters on a feeder or unique settings for each individual inverter. Seven distinctly different utility distribution feeders are analyzed to simulate the potential benefit in terms of hosting capacity, system losses, and reactive power attained with each method to determine the advanced inverter settings.

14 SOLAR ENERGY↗
NASA NTRS2011

A Validation Study of Merging and Spacing Techniques in a NAS-Wide Simulation

In November 2010, Intelligent Automation, Inc. (IAI) delivered an M&S software tool to that allows system level studies of the complex terminal airspace with the ACES simulation. The software was evaluated against current day arrivals in the Atlanta TRACON using Atlanta's Hartsfield-Jackson International Airport (KATL) arrival schedules. Results of this validation effort are presented describing data sets, traffic flow assumptions and techniques, and arrival rate comparisons between reported landings at Atlanta versus simulated arrivals using the same traffic sets in ACES equipped with M&S. Initial results showed the simulated system capacity to be significantly below arrival capacity seen at KATL. Data was gathered for Atlanta using commercial airport and flight tracking websites (like FlightAware.com), and analyzed to insure compatible techniques were used for result reporting and comparison. TFM operators for Atlanta were consulted for tuning final simulation parameters and for guidance in flow management techniques during high volume operations. Using these modified parameters and incorporating TFM guidance for efficiencies in flowing aircraft, arrival capacity for KATL was matched for the simulation. Following this validation effort, a sensitivity study was conducted to measure the impact of variations in system parameters on the Atlanta airport arrival capacity.

Glaab, Patricia C.↗
NASA NTRS1979

Data System Implications Derived from User Application Requirements for Satellite Data

An investigation of the data system needs as driven by users of space acquired Earth observation data is documented. Two major categories of users, operational and research, are identified. Limiting data acquisition alleviates some of the delays in processing thus improving timeliness of the delivered product. Trade offs occur between timeliness and data distribution costs, and between data storage and reprocessing. The complexity of the data system requirements to apply space data to users' needs is such that no single analysis suffices to design and implement the optimum system. A series of iterations is required with analyses of the salient problems in a general way, followed by a limited implementation of benefit to some users with a continual upgrade in system capacity, functions, and applications served. The resulting most important requirement for the data system is flexibility to accommodate changing requirements as the system is implemented.

Neiers, J.↗
DOE OSTI2017

Impact of a counter-rotating planetary rotation system on thin-film thickness and uniformity

Planetary rotation systems incorporating forward- and counter-rotating planets are used as a means of increasing coating-system capacity for large oblong substrates. Comparisons of planetary motion for the two types of rotating systems are presented based on point tracking for multiple revolutions, as well as comparisons of quantitative thickness and uniformity. Counter-rotation system geometry is shown to result in differences in thin-film thickness relative to standard planetary rotation for precision optical coatings. As a result, this systematic error in thin-film thickness will reduce deposition yields for sensitive coating designs.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Enhancing capacity of optical links using polarization multiplexing

5G mobile networks targets wireless connection capacity up to 10 Gb/s. For this purpose, we propose a method to considerably increase capacity. In this paper first, we show how to compensate the effects of polarization mode dispersion (PMD) in systems with double polarizations where PMD in such systems could cause fluctuations in optical transmission due to crosstalk and cross phase modulation. Second, we show how to enhance system capacity benefiting from polarization multiplexing (POL-MUX) technique which can provide double bandwidth efficiency. Based on the simulation results, we have achieved optimum system performance and we were able to reduce the PMD effect using pre- and post-compensation. We also have improved the POL-MUX technique using coherent detection in case of 16/64 QAM modulations. The results were achieved by implementing polarization controllers, polarization beam combiners and splitters, as well as polarization phase shifters.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
NASA NTRS2003

Industry Support

NASA Glenn Research Center (GRC) is responsible for the Advanced Communications for Air Traffic Management (AC/ATM) Project, a sub-element task of the Advanced Air Transportation Technologies (AATT) Project of the NASA Aviation System Capacity Program (ASC). The AC/ATM Project is developing new communications technologies and tools that will improve throughput in the U.S. Air Traffic Control System. The goal of the AC/ATM Project is to enable a communications infrastructure providing the capacity, efficiency, and flexibility necessary to realize benefits of the future mature Free-Flight environment. The capabilities and scope of communications technologies needed to accomplish this goal depend on characteristics of the future Free-Flight environment. There are many operational concepts being proposed for a future ATM system to enable user flexibility and efficiency. GRC s focus is on developing new technologies and techniques to support the digital communication of information involving airborne and ground-based users. However, the technologies and techniques must be integrated with the systems and services that industry and the Federal Aviation Administration (FAA) are developing. Thus, GRC needs to monitor and provide input to the various industry and FAA organizations and committees that are specifying new systems and services. Adoption of technologies by the FAA is partially dependent on acceptance of the technology by the aviation community. The commercial aviation community in particular would like to adopt technologies that can be used throughout the world. As a result, the adoption of common or at least compatible technologies by European countries is a key factor in getting commitments to those technologies by the US aviation community. GRC desires to keep informed of European activities that relate to aviation communication technologies, particularly those that are being supported by Eurocontrol.

Source record↗
DOE OSTI2027

Nodal capacity expansion planning with flexible large-scale load siting

We propose explicitly incorporating large-scale load siting into a stochastic nodal power system capacity expansion planning model that concurrently co-optimizes generation, transmission, and storage expansion. The potential operational flexibility of some of these large loads is also taken into account by considering them as consisting of a set of tranches with different reliability requirements, which are modeled as a constraint on expected served energy across operational scenarios. We implement our model as a two-stage stochastic mixed-integer optimization problem with cross-scenario expectation constraints. To overcome the challenge of scalability, we build upon existing work to implement this model on a high performance computing platform and exploit scenario parallelization using an augmented Progressive Hedging Algorithm. The algorithm is implemented using the bounding features of mpisppy, which have shown to provide satisfactory provable optimality gaps despite the absence of theoretical guarantees of convergence. We test our approach and assess the value of this proactive planning framework on total system cost and reliability metrics using realistic testcases geographically assigned to San Diego and South Carolina, with datacenter and direct air capture facilities as large loads.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2026

Powered By CADET

The Capacity Expansion Decision Support for Distribution Networks (CADET) is a Python-based library and framework for creating electrical distribution system capacity planning tools for cost-effective, reliable power delivery. It enables the creation of modular, scalable, and extensible distribution capacity planning tools by providing a high-level optimization interface, parameter and options data managers, optimization constraint and objective libraries, generalized nomenclature, a system for tracking and modifying distribution network changes, optimization solution validation, and other capabilities. This webinar will describe 1) the motivation for creating CADET, 2) key designs, and 3) several use cases.

24 POWER TRANSMISSION AND DISTRIBUTION↗
NASA NTRS2008

The Liquid Nitrogen System for Chamber A: A Change from Original Forced Flow Design to a Natural Flow (Thermo Siphon) System

NASA Johnson Space Center (JSC) in Houston is currently supplementing its 20K helium refrigeration system to meet the new requirements for testing the James Web Space Telescope in the environmental control Chamber-A (65 dia x 120 high) in Building 32. The new system is required to meet the various operating modes which include a high 20K heat load, a required temperature stability at the load, rapid (but controlled) cool down and warm up and bake out of the chamber. This paper will present the proposed modifications to the existing helium system(s) to incorporate the new requirements and the integration of the new helium refrigerator with the existing two 3.5KW 20K helium refrigerators. In addition, the floating pressure process control philosophy to achieve high efficiency over the operating range (40% to 100% of the refrigeration system capacity), and the required temperature stability of +/- 0.25 K at the load will be discussed. The refrigeration systems ability to naturally seek the operating conditions under various loads and thus minimizing operator involvement and the over all improvements to the system operability and the reliability will be explained.

Homan, Jonathan↗
NASA NTRS1979

Spectrum sharing considerations between radar and fixed satellite services

It is suggested that the real though constrained utility of sharing be maximized through the application of a system engineering approach. It is stressed that sharing should be applied to those situations where the overall system capacity can be most enhanced; when sharing is not feasible between radar and conventional FDM-FM voice systems, it may be applicable for other interference-resistant modulation forms. It is noted that a limitation on satellite power radiation is needed in the form of a power flux density limit, that more work is needed to develop performance standards for pulse blanking, and that video and digital links need to be looked at more closely. It is emphasized that every link that can be operated in a shared band segment frees spectrum and transponder capacity in the 3.7-4.2 GHz band.

Kinal, G. V.↗
DOE OSTI2022

Generation of Data-Driven Expected Energy Models for Photovoltaic Systems

Although unique expected energy models can be generated for a given photovoltaic (PV) site, a standardized model is also needed to facilitate performance comparisons across fleets. Current standardized expected energy models for PV work well with sparse data, but they have demonstrated significant over-estimations, which impacts accurate diagnoses of field operations and maintenance issues. This research addresses this issue by using machine learning to develop a data-driven expected energy model that can more accurately generate inferences for energy production of PV systems. Irradiance and system capacity information was used from 172 sites across the United States to train a series of models using Lasso linear regression. The trained models generally perform better than the commonly used expected energy model from international standard (IEC 61724-1), with the two highest performing models ranging in model complexity from a third-order polynomial with 10 parameters (Radj2 = 0.994) to a simpler, second-order polynomial with 4 parameters (Radj2=0.993), the latter of which is subject to further evaluation. Subsequently, the trained models provide a more robust basis for identifying potential energy anomalies for operations and maintenance activities as well as informing planning-related financial assessments. We conclude with directions for future research, such as using splines to improve model continuity and better capture systems with low (≤1000 kW DC) capacity.

14 SOLAR ENERGY↗
NASA NTRS1996

UNIX-based operating systems robustness evaluation

Robust operating systems are required for reliable computing. Techniques for robustness evaluation of operating systems not only enhance the understanding of the reliability of computer systems, but also provide valuable feed- back to system designers. This thesis presents results from robustness evaluation experiments on five UNIX-based operating systems, which include Digital Equipment's OSF/l, Hewlett Packard's HP-UX, Sun Microsystems' Solaris and SunOS, and Silicon Graphics' IRIX. Three sets of experiments were performed. The methodology for evaluation tested (1) the exception handling mechanism, (2) system resource management, and (3) system capacity under high workload stress. An exception generator was used to evaluate the exception handling mechanism of the operating systems. Results included exit status of the exception generator and the system state. Resource management techniques used by individual operating systems were tested using programs designed to usurp system resources such as physical memory and process slots. Finally, the workload stress testing evaluated the effect of the workload on system performance by running a synthetic workload and recording the response time of local and remote user requests. Moderate to severe performance degradations were observed on the systems under stress.

Chang, Yu-Ming↗
NASA NTRS2004

Erlang B/C Link Availability/Blockage for Data and Voice over VDL Mode 3

This study looks into the blockage and availability of Digital VHF Mode 3 link. Using future predicted voice and CPDLC data traffic loads, the Erlang B and Erlang C formulas were utilized to measure the availability/blockage of the two applications over VDL mode 3. The results here, along with previous cell capacity calculations on the number of frequency channels available done as a part of a separate study, can give a measure of the overall system capacity. This study shows sufficient availability (for acceptable blockage levels for worst case traffic loads. It is found that overall the voice communications will reduce the system availability the most, followed by Management accessing portion of the data which turns limits the CPDLC capability.

Shamma, Mohammed A.↗
DOE OSTI2017

Tehachapi Wind Energy Storage Project - Technology Performance Report #3

The TSP is located at SCE’s Monolith Substation in Tehachapi, California. The 8 MW, 4 hours (32 MWh) BESS is housed in a 6,300 square foot facility and 2 x 4 MW/4.5 MVA smart inverters are on a concrete pad adjacent to the BESS facility. The project will evaluate the capabilities of the BESS to improve grid performance and assist in the integration of large-scale intermittent generation, e.g., wind. Project performance was measured by 13 specific operational uses: providing voltage support and grid stabilization, decreasing transmission losses, diminishing congestion, increasing system reliability, deferring transmission investment, optimizing renewable-related transmission, providing system capacity and resources adequacy, integrating renewable energy (smoothing), shifting wind generation output, frequency regulation, spin/non-spin replacement reserves, ramp management, and energy price arbitrage. Most of the operations either shift other generation resources to meet peak load and other electricity system needs with stored electricity, or resolve grid stability and capacity concerns that result from the interconnection of intermittent generation. SCE also demonstrated the ability of lithium ion battery storage to provide nearly instantaneous maximum capacity for supply-side ramp rate control to minimize the need for fossil fuel-powered back-up generation. The project began in October, 2010 and will continue through December, 2016.

25 ENERGY STORAGE↗
NASA NTRS1971

Adaptive multisatellite systems for aeronautical services.

The use of satellite systems to provide operational communications and ATC services to aircraft flying the oceanic routes has been the subject of considerable interest recently. Since most of the link factors are functions of geometry and the aircraft traffic density varies with time, the satellite power needed to meet the communication demand varies considerably in an oceanic area as a function of both location and time. An adaptive system that tailors the use of system resources to the needs of the user can result in an additional system capacity improvement by a factor of between two and three. Results of studies conducted to date indicate that simple implementation of adaptive techniques in aeronautical satellite systems is feasible. Study is continuing in this area and on the application of satellite multibeam techniques to gain even further increase in capacity.

Bisaga, J. J.↗
NASA NTRS2002

Toward a Concept of Operations for Aviation Weather Information Implementation in the Evolving National Airspace System

The capacity of the National Airspace System is being stressed due to the limits of current technologies. Because of this, the FAA and NASA are working to develop new technologies to increase the system's capacity which enhancing safety. Adverse weather has been determined to be a major factor in aircraft accidents and fatalities and the FAA and NASA have developed programs to improve aviation weather information technologies and communications for system users The Aviation Weather Information Element of the Weather Accident Prevention Project of NASA's Aviation Safety Program is currently working to develop these technologies in coordination with the FAA and industry. This paper sets forth a theoretical approach to implement these new technologies while addressing the National Airspace System (NAS) as an evolving system with Weather Information as one of its subSystems. With this approach in place, system users will be able to acquire the type of weather information that is needed based upon the type of decision-making situation and condition that is encountered. The theoretical approach addressed in this paper takes the form of a model for weather information implementation. This model addresses the use of weather information in three decision-making situations, based upon the system user's operational perspective. The model also addresses two decision-making conditions, which are based upon the need for collaboration due to the level of support offered by the weather information provided by each new product or technology. The model is proposed for use in weather information implementation in order to provide a systems approach to the NAS. Enhancements to the NAS collaborative decision-making capabilities are also suggested.

McAdaragh, Raymon M.↗