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Experimental results on the two-stage, Venetian Blind, direct energy converter

Description: Some preliminary results obtained from experiments designed to test the feasibility of the Venetian Blind, direct energy-conversion concept are discussed. A two-stage unit was built and tested and found to have an overall efficiency of 65% for an energy spread of from 330 to 1000 eV. The calculated efficiency was 69% leaving a 4% discrepancy. This discrepancy seems to result from the slight transparency in the backward direction of the ribbons of the converter. (auth)
Date: February 1, 1974
Creator: Moir, R. W. & Barr, W. L.
Partner: UNT Libraries Government Documents Department

Voltage holding considerations for direct-collection units

Description: Results have been obtained from initial experiments designed to study high-voltage breakdown under conditions of importance to the design of direct- collection units. A coaxial configuration was used to mock-up critical fields near grid wires. With appropriate heat conditioning, fields as high as 9.6 x 10/ sup 5/ V/cm were maintained at the surface of a 7-mil-diam tungsten wire. This represents an enhanced field of ~10/sup 8/V/cm at whisker'' sites. Breakdown criteria are proposed for three regimes; initial, field-emission, and ultimate, which differ by the amount of prior conditioning applied to the wire. Additional considerations of importance to direct collectors such as the effect of thermionic emission and ion bombardment are discussed. (auth)
Date: December 1, 1973
Creator: Miley, G.H.
Partner: UNT Libraries Government Documents Department

Technology Development: Wireless Sensors and Controls BT0201 Review of Energy Scavenging Schemes and Recommended Order of Investigation

Description: This report reviews the characteristics of four candidate concepts that extract and convert ambient energy to provide electrical power for wireless sensors.
Date: September 1, 2004
Creator: DeSteese, John G.; Olsen, Larry C. & Schienbein, Lawrence A.
Partner: UNT Libraries Government Documents Department

Surface requirements for electrostatic direct energy converters

Description: From surface effects in controlled thermonuclear fusion devices and reactors meeting; Argonne, Illinois, USA (10 Jan 1974). There are two major electrostatic direct energy converter concepts whlch will be discussed from the point of view of the surfaces. One is the Venetian blind concept and the other is the periodic electrostatic focusing concept. They are both of the direct collector type. Fluxes of D/sup +/, T/sup +/, He/sup ++/, electrons, and x-rays are given. Design consideration due to thermionic emission, secondary electron emission, and radiation cooling are discussed. A detailed discussion is devoted to breakdown physics, the voltages and electric field strengths that can be employed, and how surface deterioration may affect voltage holding due to He/sup ++/ bombardment blistering. (auth)
Date: January 17, 1974
Creator: Moir, R.W.; Barr, W.L. & Miley, G.H.
Partner: UNT Libraries Government Documents Department

Institutional aspects of fuel-cell total-energy system: a summary survey

Description: The institutional impediments to market penetration by fuel cells are briefly discussed including the following topics: (1) ownership of fuel cell and related franchise limitations; (2) backup arrangements; (3) economic effects; (4) fuel policy; (5) regulatory proceedings; and (6) competitive response. (WHK)
Date: July 31, 1977
Partner: UNT Libraries Government Documents Department

Surface conditions in a conceptual D--T mirror reactor with direct conversion

Description: From surface effects in controlled thermonuclear fusion devices and reactors meeting; Argonne, Illinois, USA (10 Jan 1974). A conceptual D-T fusion reactor employing magnetic mirror confinement and periodic focusing electrostatic direct conversion is described with emphasis on surface conditions. (auth)
Date: January 23, 1974
Creator: Lee, J.D.
Partner: UNT Libraries Government Documents Department

Design studies of mirror machine reactors

Description: An overview is presented of a mirror fusion reactor design study. The general methodology used in the study is discussed, the reactor is described, and some design alternatives to the present approach are enumerated. The system chosen for this design study is a mirror machine with direct conversion using D- T fuel. The nominal power output is 200 MW. The coil geometry is the Yin Yang, minimum B with a vacuum mirror ratio of 3. The coil is of particular utility because of its simple conductor shapes and because the two separate conductors, by proper B-field biasing, allow the charged particles to escape preferentially through one mirror only and through a relatively small window'' of that mirror. This is necessary for direct converter economy. (auth)
Date: December 1, 1973
Creator: Werner, R.W.; Carlson, G.A.; Hovingh, J.; Lee, J.D. & Peterson, M.A.
Partner: UNT Libraries Government Documents Department

Status of the DOE Battery and Electrochemical Technology Program V

Description: The program consists of two activities, Technology Base Research (TBR) managed by the Lawrence Berkeley Laboratory (LBL) and Exploratory Technology Development and Testing (EDT) managed by the Sandia National Laboratories (SNL). The status of the Battery Energy Storage Test (BEST) Facility is presented, including the status of the batteries to be tested. ECS program contributions to the advancement of the lead-acid battery and specific examples of technology transfer from this program are given. The advances during the period December 1982 to June 1984 in the characterization and performance of the lead-acid, iron/nickel-oxide, iron/air, aluminum/air, zinc/bromide, zinc/ferricyanide, and sodium/sulfur batteries and in fuel cells for transport are summarized. Novel techniques and the application of established techniques to the study of electrode processes, especially the electrode/electrolyte interface, are described. Research with the potential of leading to improved ceramic electrolytes and positive electrode container and current-collectors for the sodium/sulfur battery is presented. Advances in the electrocatalysis of the oxygen (air) electrode and the relationship of these advances to the iron/air and aluminum/air batteries and to the fuel cell are noted. The quest for new battery couples and battery materials is reviewed. New developments in the modeling of electrochemical cell and electrode performance with the approaches to test these models are reported.
Date: June 1, 1985
Creator: Roberts, R.
Partner: UNT Libraries Government Documents Department

A New Fabrication Process for Thin-Film Multijunction Thermal Converters

Description: Advanced thin film processing and packaging technologies are employed in the fabrication of new planar thin-film multifunction thermal converters. The processing, packaging, and design features build on experience gained from prior NIST demonstrations of thin-film converters and are optimized for improved sensitivity, bandwidth, manufacturability, and reliability.
Date: December 8, 2000
Partner: UNT Libraries Government Documents Department

Direct energy conversion in fission reactors: A U.S. NERI project

Description: In principle, the energy released by a fission can be converted directly into electricity by using the charged fission fragments. The first theoretical treatment of direct energy conversion (DEC) appeared in the literature in 1957. Experiments were conducted over the next ten years, which identified a number of problem areas. Research declined by the late 1960's due to technical challenges that limited performance. Under the Nuclear Energy Research Initiative the authors are determining if these technical challenges can be overcome with todays technology. The authors present the basic principles of DEC reactors, review previous research, discuss problem areas in detail, and identify technological developments of the last 30 years that can overcome these obstacles. As an example, the fission electric cell must be insulated to avoid electrons crossing the cell. This insulation could be provided by a magnetic field as attempted in the early experiments. However, from work on magnetically insulated ion diodes they know how to significantly improve the field geometry. Finally, a prognosis for future development of DEC reactors will be presented .
Date: May 30, 2000
Partner: UNT Libraries Government Documents Department

Reduction of photovoltaic cell reverse breakdown by a peripheral bypass diode

Description: A photovoltaic cell in a series-connected string can be forced to operate in a power-dissipation mode when the cell's short-circuit current is reduced below the string current as a result of cracking or shadowing. New techniques for significantly reducing the power dissipated are reported based on locating protection for the cell around its periphery. One approach uses a standard diode, thereby requiring processing; the other approach uses a backward diode, which requires one additional doping step. Theoretical considerations and experimental results are presented. Initial devices yield a power-dissipation reduction of more than a factor of 10 with the backward diode and over 30 for the standard diode. It is found that the standard diode requires a slight increase in cell-interconnect complexity while the backward diodes uses conventional interconnections.
Date: January 1, 1982
Creator: Cox, III, C H; Silversmith, D J & Mountain, R W
Partner: UNT Libraries Government Documents Department

Module Utilization Committee. Final report

Description: Photovoltaic collector modules were declared surplus to the needs of the US Department of Energy. The Module Utilization Committee was formed to make appropriate disposition of the surplus modules. The final report of that committee accounts for that disposition. The membership and activities of the committee are set forth and the results of its activities are reported.
Date: March 1, 1984
Partner: UNT Libraries Government Documents Department

Determination of a definition of solar grade silicon. Third quarterly report, 1 April--30 June 1976

Description: All scheduled experimental crystals have been grown. Analysis is about 75 percent complete; solar cell work is about 50 percent complete. Minority carrier life-time measurements are 90 percent done. From the results we conclude not only do solar cells tolerate certain impurities but cells built in silicon containing controlled amounts (up to one ppM) of magnesium, manganese and nickel, singly or combined, have actually higher-than-baseline performances. On the other hand, iron, chromium, vanadium and particularly titanium, reduce conversion efficiency from slightly to catastrophically. The influence of carbon is perhaps only marginal but no doubt is left about oxygen. Oxygen levels about 50 ppM, i.e., about 10/sup 18/ atoms/cc reduce device performance definitely.
Date: January 1, 1976
Creator: Christ, M. H.; Gupta, K. P.; Gutsche, H. W.; Hill, D. E.; Tucker, W. F. & Wang, M. S.
Partner: UNT Libraries Government Documents Department

Trimode Power Converter optimizes PV, diesel and battery energy sources

Description: Conservatively, there are 100,000 localities in the world waiting for the benefits that electricity can provide, and many of these are in climates where sunshine is plentiful. With these locations in mind a prototype 30 kW hybrid system has been assembled at Sandia to prove the reliability and economics of photovoltaic, diesel and battery energy sources managed by an autonomous power converter. In the Trimode Power Converter the same power parts, four IGBT`s with an isolation transformer and filter components, serve as rectifier and charger to charge the battery from the diesel; as a stand-alone inverter to convert PV and battery energy to AC; and, as a parallel inverter with the diesel-generator to accommodate loads larger than the rating of the diesel. Whenever the diesel is supplying the load, an algorithm assures that the diesel is running at maximum efficiency by regulating the battery charger operating point. Given the profile of anticipated solar energy, the cost of transporting diesel fuel to a remote location and a five year projection of load demand, a method to size the PV array, battery and diesel for least cost is developed.
Date: July 1, 1994
Creator: O`Sullivan, G.; Bonn, R. & Bower, W.
Partner: UNT Libraries Government Documents Department