100 research outputs found
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Remote Area Power Supply (RAPS) load and resource profiles.
In 1997, an international team interested in the development of Remote Area Power Supply (RAPS) systems for rural electrification projects around the world was organized by the International Lead Zinc Research Organization (ILZRO) with the support of Sandia National Laboratories (SNL). The team focused on defining load and resource profiles for RAPS systems. They identified single family homes, small communities, and villages as candidates for RAPS applications, and defined several different size/power requirements for each. Based on renewable energy and resource data, the team devised a ''strawman'' series of load profiles. A RAPS system typically consists of a renewable and/or conventional generator, power conversion equipment, and a battery. The purpose of this report is to present data and information on insolation levels and load requirements for ''typical'' homes, small communities, and larger villages around the world in order to facilitate the development of robust design practices for RAPS systems, and especially for the storage battery component. These systems could have significant impact on areas of the world that would otherwise not be served by conventional electrical grids
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Reliability of valve-regulated lead-acid batteries for stationary applications.
A survey has been carried out to quantify the performance and life of over 700,000 valve-regulated lead-acid (VRLA) cells, which have been or are being used in stationary applications across the United States. The findings derived from this study have not identified any fundamental flaws of VRLA battery technology. There is evidence that some cell designs are more successful in float duty than others. A significant number of the VRLA cells covered by the survey were found to have provided satisfactory performance
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Summary of the laser working group
The laser working group considered several options to deliver synchronized laser pulses of the required energy to the photocathode and laser triggered switches. These requirements actually decreased during the course of the workshop, and the values finally settled upon (<10 {mu}J in 100 fs at {approximately}250 nm for the photocathode and {approximately}20 mJ in 2 ps near either 250 nm or 1 {mu}m for the switches) were considered to be well within the state of the art. Some development work may be required, however, to provide a system that has the desirable characteristics of stability, ease of use and low maintenance. The baseline concept, which is similar to a number of existing systems, utilizes doubled Nd:YAG-pumped dye oscillator/amplifiers to produce an upconverted picosecond pulse that can be amplified to tens of mJ in a KrF excimer laser. A fraction of the dye oscillator output is also compressed by means of a fiber-grating compressor and further amplified in a dye amplifier before being upconverted to produce the synchronized pulse for the photocathode. 9 refs., 1 fig
Review of in-situ process monitoring and in-situ metrology for metal additive manufacturing
Lack of assurance of quality with additively manufactured (AM) parts is a key technological barrier that prevents manufacturers from adopting AM technologies, especially for high-value applications where component failure cannot be tolerated. Developments in process control have allowed significant enhancement of AM techniques and marked improvements in surface roughness and material properties, along with a reduction in inter-build variation and the occurrence of embedded material discontinuities. As a result, the exploitation of AM processes continues to accelerate. Unlike established subtractive processes, where in-process monitoring is now commonplace, factory-ready AM processes have not yet incorporated monitoring technologies that allow discontinuities to be detected in process. Researchers have investigated new forms of instrumentation and adaptive approaches which, when integrated, will allow further enhancement to the assurance that can be offered when producing AM components. The state-of-the-art with respect to inspection methodologies compatible with AM processes is explored here. Their suitability for the inspection and identification of typical material discontinuities and failure modes is discussed with the intention of identifying new avenues for research and proposing approaches to integration into future generations of AM systems
Model-based assessment of energy-efficiency, dependability, and cost-effectiveness of waste heat recovery systems onboard ship
YesTechnological systems are not merely designed with a narrow function in mind. Good designs typically aim at reducing operational costs, e.g. through achieving high energy efficiency and improved dependability (i.e. reliability, availability and maintainability). When there is a choice of alternative design options that perform the same function, it makes sense to compare alternatives so that the variant that minimises operational costs can be selected. In this paper, we examine this issue in the context of the design of Waste Heat Recovery Systems (WHRS) for main engines of large commercial freight vessels. We propose a method that can predict the operational cost of a WHRS via thermodynamic analysis which shows costs related to energy utilisation, and dependability analysis which shows costs related to system unavailability and repair. Our approach builds on recent advances in thermodynamic simulation and compositional dependability analysis techniques. It is a model-based approach, and allows reuse of component libraries, and a high degree of automation which simplify application of the method. Our case study shows that alternative designs can be explored in fast iterations of this method, and that this facilitates the evidence-based selection of a design that minimises operational costs
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Characterizations of Hydrogen Energy Technologies
In 1996, Dr. Ed Skolnik of Energetics, Incorporated, began a series of visits to the locations of various projects that were part of the DOE Hydrogen Program. The site visits/evaluations were initiated to help the DOE Program Management, which had limited time and limited travel budgets, to get a detailed snapshot of each project. The evaluations were soon found to have other uses as well: they provided reviewers on the annual Hydrogen Program Peer Review Team with an in-depth look at a project--something that is lacking in a short presentation--and also provided a means for hydrogen stakeholders to learn about the R&D that the Hydrogen Program is sponsoring. The visits were conducted under several different contract mechanisms, at project locations specified by DOE Headquarters Program Management, Golden Field Office Contract Managers, or Energetics, Inc., or through discussion by some or all of the above. The methodology for these site-visit-evaluations changed slightly over the years, but was fundamentally as follows: Contact the Principal Investigator (PI) and arrange a time for the visit; Conduct a literature review. This would include a review of the last two or three years of Annual Operating Plan submittals, monthly reports, the paper submitted with the last two or three Annual Peer Review, published reviewers' consensus comments from the past few years, publications in journals, and journal publications on the same or similar topics by other researchers; Send the PI a list of questions/topics about a week ahead of time, which we would discuss during the visit. The types of questions vary depending on the project, but include some detailed technical questions that delve into some fundamental scientific and engineering issues, and also include some economic and goal-oriented topics; Conduct the site-visit itself including--Presentations by the PI and/or his staff. This would be formal in some cases, informal in others, and merely a ''sit around the table'' discussion in others; The format was left to the discretion of the PI; A tour of the facility featuring, whenever possible, a demonstration of the process in operation; Detailed discussions of the questions sent to the PI and other topics; and Writing a report on the visit. This compilation presents the reports for all the site-visits held between February 1996 and July 2001, each written shortly after the visit. While nothing has been changed in the actual content of any of the reports, reformatting for uniformity did occur. In each report, where the questions and their respective answers are discussed, the questions are shown in bold. In several cases, the PI chose to answer these questions in writing. When this occurs, the PI's answers are produced ''verbatim, in quotes, using a different font.'' Discussion of the questions, tour/demonstration, and anything else raised during the visit is presented in normal type. Comments that represent the opinion of Dr. Skolnik, including those added during the writing of the report are shown in italics. The reports compiled here, as stated, covers a period through July 2001. Since then, site-visits to various project locations and the accompanying evaluations have continued. Thus, a second compilation volume should follow in the fall of 2003. Following the compilation of reports, is an afterward that briefly discusses what has happened to some of the projects or project personnel since that particular report was written
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Energetics Inc
This report includes thirteen site-visit-based analyses or assessments of hydrogen R&D projects as well as four analyses of hydrogen process scenarios. The latter include the use of hydrogen/bromine electricity storage, hydrogen as a bus fuel, low-rank coal as thermal source to regenerate hydrides, and sodium hydride on-board storage
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Cryogenics Vision Workshop for High-Temperature Superconducting Electric Power Systems Proceedings
The US Department of Energy's Superconductivity Program for Electric Systems sponsored the Cryogenics Vision Workshop, which was held on July 27, 1999 in Washington, D.C. This workshop was held in conjunction with the Program's Annual Peer Review meeting. Of the 175 people attending the peer review meeting, 31 were selected in advance to participate in the Cryogenics Vision Workshops discussions. The participants represented cryogenic equipment manufactures, industrial gas manufacturers and distributors, component suppliers, electric power equipment manufacturers (Superconductivity Partnership Initiative participants), electric utilities, federal agencies, national laboratories, and consulting firms. Critical factors were discussed that need to be considered in describing the successful future commercialization of cryogenic systems. Such systems will enable the widespread deployment of high-temperature superconducting (HTS) electric power equipment. Potential research, development, and demonstration (RD and D) activities and partnership opportunities for advancing suitable cryogenic systems were also discussed. The workshop agenda can be found in the following section of this report. Facilitated sessions were held to discuss the following specific focus topics: identifying Critical Factors that need to be included in a Cryogenics Vision for HTS Electric Power Systems (From the HTS equipment end-user perspective) identifying R and D Needs and Partnership Roles (From the cryogenic industry perspective) The findings of the facilitated Cryogenics Vision Workshop were then presented in a plenary session of the Annual Peer Review Meeting. Approximately 120 attendees participated in the afternoon plenary session. This large group heard summary reports from the workshop session leaders and then held a wrap-up session to discuss the findings, cross-cutting themes, and next steps. These summary reports are presented in this document. The ideas and suggestions raised during the Workshop will be used by the DOE Superconductivity Program for Electric Systems in preparing subsequent planning and strategy documents such as a Cryogenic Technology Development Roadmap
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Evaluation of battery/microturbine hybrid energy storage technologies at the University of Maryland :a study for the DOE Energy Storage Systems Program.
This study describes the technical and economic benefits derived from adding an energy storage component to an existing building cooling, heating, and power system that uses microturbine generation to augment utility-provided power. Three different types of battery energy storage were evaluated: flooded lead-acid, valve-regulated lead-acid, and zinc/bromine. Additionally, the economic advantages of hybrid generation/storage systems were evaluated for a representative range of utility tariffs. The analysis was done using the Distributed Energy Technology Simulator developed for the Energy Storage Systems Program at Sandia National Laboratories by Energetics, Inc. The study was sponsored by the U.S. DOE Energy Storage Systems Program through Sandia National Laboratories and was performed in coordination with the University of Maryland's Center for Environmental Energy Engineering
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