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Design Configurations for a Very High Temperature Gas-Cooled Reactor Designed to Generate Electricity and Hydrogen

Description: The High Temperature Gas-Cooled Reactor is being envisioned that will generate not just electricity, but also hydrogen to charge up fuel cells for cars, trucks and other mobile energy uses. INL engineers studied various heat-transfer working fluids—including helium and liquid salts—in seven different configurations. In computer simulations, serial configurations diverted some energy from the heated fluid flowing to the electric plant and hydrogen production plant. In anticipation of the design, development and procurement of an advanced power conversion system for HTGR, this study was initiated to identify the major design and technology options and their tradeoffs in the evaluation of power conversion system (PCS) coupled to hydrogen plant. In this study, we investigated a number of design configurations and performed thermal hydraulic analyses using various working fluids and various conditions (Oh, 2005). This paper includes a portion of thermal hydraulic results based on a direct cycle and a parallel intermediate heat exchanger (IHX) configuration option.
Date: July 1, 2006
Creator: preceedings, Conference
Partner: UNT Libraries Government Documents Department

HyPEP-FY 07 Annual Report: A Hydrogen Production Plant Efficiency Calculation Program

Description: The Very High Temperature Gas-Cooled Reactor (VHTR) coupled to the High Temperature Steam Electrolysis (HTSE) process is one of two reference integrated systems being investigated by the U.S. Department of Energy and Idaho National Laboratory for the production of hydrogen. In this concept the VHTR outlet temperature of 900 °C provides thermal energy and high efficiency electricity for the electrolysis of steam in the HTSE process. In the second reference system the Sulfur Iodine (SI) process is coupled to the VHTR to produce hydrogen thermochemically. In the HyPEP project we are investigating and characterizing these two reference systems with respect to production, operability, and safety performance criteria. Under production, plant configuration and working fluids are being studied for their effect on efficiency. Under operability, control strategies are being developed with the goal of maintaining equipment within operating limits while meeting changes in demand. Safety studies are to investigate plant response for equipment failures. Specific objectives in FY07 were (1) to develop HyPEP Beta and verification and validation (V&V) plan, (2) to perform steady state system integration, (3) to perform parametric studies with various working fluids and power conversion unit (PCU) configurations, (4) the study of design options such as pressure, temperature, etc. (5) to develop a control strategy and (6) to perform transient analyses for plant upsets, control strategy, etc for hydrogen plant with PCU. This report describes the progress made in FY07 in each of the above areas. (1) The HyPEP code numeric scheme and Graphic User Interface have been tested and refined since the release of the alpha version a year ago. (2) The optimal size and design condition for the intermediate heat exchanger, one of the most important components for integration of the VHTR and HTSE plants, was estimated. (3) Efficiency calculations were performed for a variety ...
Date: September 1, 2007
Creator: Oh, Chang
Partner: UNT Libraries Government Documents Department

Critical Function Models for Operation of the International Space Station

Description: Long duration and exploration class space missions will place new requirements on human performance when compared to current space shuttle missions. Specifically, assembly and operation of the International Space Station (ISS) will place significant new demands on the crew. For example, maintenance of systems that provide habitability will become an ongoing activity for the international flight crews. Tasks for maintaining space station habitability will need to be integrated with tasks associated with scientific research. In addition, tasks and resources will need to be prioritized and allocated dynamically in response to changing operational conditions and unplanned system breakdowns. This paper describes an ongoing program to develop a habitability index (HI) for space operations based on the critical function approach. This pilot project focuses on adaptation of the critical function approach to develop a habitability index specifically tailored for space operations. Further work will then be needed to expand and validate the habitability index for application in the ISS operational environment.
Date: November 1, 2000
Creator: Nelson, William Roy & Bagian, T. M.
Partner: UNT Libraries Government Documents Department

IEA Wind Task 24 Integration of Wind and Hydropower Systems; Volume 1: Issues, Impacts, and Economics of Wind and Hydropower Integration

Description: This report describes the background, concepts, issues and conclusions related to the feasibility of integrating wind and hydropower, as investigated by the members of IEA Wind Task 24. It is the result of a four-year effort involving seven IEA member countries and thirteen participating organizations. The companion report, Volume 2, describes in detail the study methodologies and participant case studies, and exists as a reference for this report.
Date: December 1, 2011
Creator: Acker, T.
Partner: UNT Libraries Government Documents Department

IEA Wind Task 24 Integration of Wind and Hydropower Systems; Volume 2: Participant Case Studies

Description: This report describes the background, concepts, issues and conclusions related to the feasibility of integrating wind and hydropower, as investigated by the members of IEA Wind Task 24. It is the result of a four-year effort involving seven IEA member countries and thirteen participating organizations. The companion report, Volume 2, describes in detail the study methodologies and participant case studies, and exists as a reference for this report.
Date: December 1, 2011
Creator: Acker, T.
Partner: UNT Libraries Government Documents Department

Design Configurations and Coupling High Temperature Gas-Cooled Reactor and Hydrogen Plant

Description: The US Department of Energy is investigating the use of high-temperature nuclear reactors to produce hydrogen using either thermochemical cycles or high-temperature electrolysis. Although the hydrogen production processes are in an early stage of development, coupling either of these processes to the high-temperature reactor requires both efficient heat transfer and adequate separation of the facilities to assure that off-normal events in the production facility do not impact the nuclear power plant. An intermediate heat transport loop will be required to separate the operations and safety functions of the nuclear and hydrogen plants. A next generation high-temperature reactor could be envisioned as a single-purpose facility that produces hydrogen or a dual-purpose facility that produces hydrogen and electricity. Early plants, such as the proposed Next Generation Nuclear Plant (NGNP), may be dual-purpose facilities that demonstrate both hydrogen and efficient electrical generation. Later plants could be single-purpose facilities. At this stage of development, both single- and dual-purpose facilities need to be understood.
Date: April 1, 2008
Creator: Oh, Chang H.; Kim, Eung Soo & Sherman, Steven
Partner: UNT Libraries Government Documents Department

The VirtualwindoW: A Reconfigurable, Modular, Stereo Vision System

Description: An important need while using unmanned vehicles is the ability for the remote operator or observer to easily and accurately perceive the operating environment. A classic problem in providing a complete representation of the remote work area is sensory overload or excessive complexity in the human-machine interface. In addition, remote operations often benefit from depth perception capability while viewing or manipulating objects. Thus, there is an on going effort within the remote and teleoperated robotic field to develop better human-machine interfaces. The Department of Energy's Idaho National Engineering and Environmental Laboratory (INEEL) has been researching methods to simplify the human-machine interface using atypical operator techniques. Initial telepresence research conducted at the INEEL developed and implemented a concept called the VirtualwindoW. This system minimized the complexity of remote stereo viewing controls and provided the operator the "feel" of viewing the environment, including depth perception, in a natural setting. The VirtualwindoW has shown that the human-machine interface can be simplified while increasing operator performance. This paper deals with the continuing research and development of the VirtualwindoW to provide a reconfigurable, modular system that easily utilizes commercially available off the shelf components. This adaptability is well suited to several aspects of unmanned vehicle applications, most notably environmental perception and vehicle control.
Date: April 1, 1999
Creator: Kinoshita, Robert Arthur; Anderson, Matthew Oley; Mckay, Mark D & Willis, Walter David
Partner: UNT Libraries Government Documents Department

The VirtualwindoW: A Reconfigurable, Modular, Stereo Vision System

Description: An important need while using unmanned vehicles is the ability for the remote operator or observer to easily and accurately perceive the operating environment. A classic problem in providing a complete representation of the remote work area is sensory overload or excessive complexity in the human-machine interface. In addition, remote operations often benefit from depth perception capability while viewing or manipulating objects. Thus, there is an ongoing effort within the remote and teleoperated robotic field to develop better human-machine interfaces. The Department of Energy's Idaho National Engineering and Environmental Laboratory (INEEL) has been researching methods to simplify the human-machine interface using atypical operator techniques. Initial telepresence research conducted at the INEEL developed and implemented a concept called the VirtualwindoW. This system minimized the complexity of remote stereo viewing controls and provided the operator the ''feel'' of viewing the environment, including depth perception, in a natural setting. The VirtualwindoW has shown that the human-machine interface can be simplified while increasing operator performance. This paper deals with the continuing research and development of the VirtualwindoW to provide a reconfigurable, modular system that easily utilizes commercially available off the shelf components. This adaptability is well suited to several aspects of unmanned vehicle applications, most notably environmental perception and vehicle control.
Date: February 1, 1999
Creator: McKay, M. D.; Anderson, M. O.; Kinoshita, R. A. & Willis, W. D.
Partner: UNT Libraries Government Documents Department

Future of Grid-Tied PV Business Models: What Will Happen When PV Penetration on the Distribution Grid is Significant? Preprint

Description: Eventually, distributed PV will become a more significant part of the generation mix. When this happens, it is expected that utilities will have to take on a more active role in the placement, operation and control of these systems. There are operational complexities and concerns of revenue erosion that will drive utilities into greater involvement of distributed PV and will create new business models. This report summarizes work done by Navigant Consulting Inc. for the National Renewable Energy Laboratory as part of the Department of Energy's work on Renewable System Integration. The objective of the work was to better understand the structure of these future business models and the research, development and demonstration (RD&D) required to support their deployment. This report describes potential future PV business models in terms of combinations of utility ownership and control of the PV assets, and the various relationships between end-users and third-party owners.
Date: May 1, 2008
Creator: Graham, S.; Katofsky, R.; Frantzis, L.; Sawyer, H. & Margolis, R.
Partner: UNT Libraries Government Documents Department

Photovoltaics Value Analysis

Description: The goals of this report are to identify best practices in methodologies for estimating the value of distributed PV technologies, identify gaps in existing knowledge, and outline R&D opportunities.
Date: February 1, 2008
Creator: Contreras, J.L.; Frantzis, L.; Blazewicz, S.; Pinault, D. & Sawyer, H.
Partner: UNT Libraries Government Documents Department

CTBT integrated verification system evaluation model supplement

Description: Sandia National Laboratories has developed a computer based model called IVSEM (Integrated Verification System Evaluation Model) to estimate the performance of a nuclear detonation monitoring system. The IVSEM project was initiated in June 1994, by Sandia's Monitoring Systems and Technology Center and has been funded by the U.S. Department of Energy's Office of Nonproliferation and National Security (DOE/NN). IVSEM is a simple, ''top-level,'' modeling tool which estimates the performance of a Comprehensive Nuclear Test Ban Treaty (CTBT) monitoring system and can help explore the impact of various sensor system concepts and technology advancements on CTBT monitoring. One of IVSEM's unique features is that it integrates results from the various CTBT sensor technologies (seismic, in sound, radionuclide, and hydroacoustic) and allows the user to investigate synergy among the technologies. Specifically, IVSEM estimates the detection effectiveness (probability of detection), location accuracy, and identification capability of the integrated system and of each technology subsystem individually. The model attempts to accurately estimate the monitoring system's performance at medium interfaces (air-land, air-water) and for some evasive testing methods such as seismic decoupling. The original IVSEM report, CTBT Integrated Verification System Evaluation Model, SAND97-25 18, described version 1.2 of IVSEM. This report describes the changes made to IVSEM version 1.2 and the addition of identification capability estimates that have been incorporated into IVSEM version 2.0.
Date: March 2, 2000
Creator: EDENBURN,MICHAEL W.; BUNTING,MARCUS; PAYNE JR.,ARTHUR C. & TROST,LAWRENCE C.
Partner: UNT Libraries Government Documents Department

Energy Savings Potential of Flexible and Adaptive HVAC Distribution Systems for Office Buildings

Description: It has been understood by architects and engineers that office buildings with easily re-configurable space and flexible mechanical and electrical systems are able to provide comfort that increases worker productivity while using less energy. Raised floors are an example of how fresh air, thermal conditioning, lighting needs, and network access can be delivered in a flexible manner that is not ''embedded'' within the structure. What are not yet documented is how well these systems perform and how much energy they can save. This area is being investigated in phased projects of the 21st Century Research Program of the Air-conditioning and Refrigeration Technology Institute. For the initial project, research teams at the Center for Building Performance and Diagnostics, Pittsburgh, Pennsylvania, and Oak Ridge National Laboratory, Oak Ridge, Tennessee, documented the diversity, performance, and incidence of flexible and adaptive HVAC systems. Information was gathered worldwide from journal and conference articles, case studies, manufactured products and assemblies, and interviews with design professionals. Their report thoroughly describes the variety of system types along with the various design alternatives observed for plenums, diffusers, individual control, and system integration. Many of the systems are illustrated in the report and the authors provide quantitative and qualitative comparisons. Among conclusions regarding key design issues, and barriers to widespread adoption, the authors state that flexible and adaptive HVAC systems, such as underfloor air, perform as well if not better than ceiling-based systems. Leading engineers have become active proponents after their first experience, which is resulting in these flexible and adaptive HVAC systems approaching 10 percent of the new construction market. To encourage adoption of this technology that improves thermal comfort and indoor air quality, follow-on work is required to further document performance. Architects, professional engineers, and commercial real estate developers will benefit from the availability of information that quantifies ...
Date: June 1, 2002
Creator: Loftness, Vivian; Brahme, Rohini; Mondazzi, Michelle; Vineyard, Edward & MacDonald, Michael
Partner: UNT Libraries Government Documents Department