Thermionic tantalum emitter doped with oxygen Patent Application

Oxygen-doped tantalum emitter for thermionic devices such as cesium vapor diode

Feasibility study of oxygen-dispensing emitters for thermionic converters, phase 1

A metal/ceramic Marchuk tube was used to measure work functions of oxygen-doped tantalum, to determine applicability of the material to plasma-mode thermionic converters. Oxygen-doped tantalum was shown to increase in work function monotonically with oxygen doping in the range 0.1 to 0.3 atomic percent. Oxygenated test emitters were run at an average temperature of 2165 K and a T/T sub Cs ratio -5.8 to observe the influence of oxygen depletion. Bare work function decreased with outgassing of oxygen. Projections were made based on outgassing kinetics and area/volume ratios to calculate the longevity of oxygen doping in a practical converter. Calculations indicated that the program goal of 10,000 hr could be achieved at 1800 K with an initial oxygen doping of 1 atomic percent and a practical emitter area/volume ratio

Electrodes for the thermionic converters, phase 2 - 3

The characteristics of electrodes for thermionic converters are discussed. A metal/ceramic Marchuk tube was constructed and operated with a quiescent cesium vapor plasma corresponding to cesium liquid reservoir temperatures from 376 to 427 K. The work function characteristics of tantalum test emitters coated with anodic films were measured to evaluate the applicability of the materials as the collector surface in a plasma mode thermionic converter. Work function minimum values between 1.4 and 1.5 electron volts were observed. The effect of the electronegative surface layers was partially obscured by additive vapor impurities detected by the clean tantalum reference emitter

Identification and prioritization of concerns in coal transportation now through 2000

This review presents the results of analysis used to identify and prioritize perceived potential problems that may hinder the development of coal transportation in the United States during the balance of the century. One objective of this effort is to discriminate serious concerns affecting the overall adequacy of coal transportation systems from issues of lesser significance. The concerns with the highest priority are anticipated to impact coal transportation in the early 1980s. These concerns relate to public acceptance, logistic problems with frozen coal, the impact of slurry pipelines, and sludge transportation. Problems with the potential of impact in the balance of the century include the effects of rate rgulations on railroad incentives to haul coal, the safety and environmental impact of advanced slurry systems and congestion on inland waterways. A second objective of the analysis is to recommend specific actions that may mitigate the consequences of potential problems. The recommendations discussed in this paper include the need for new research, developments and demonstrations, risk assessments and other evaluations to fill possible gaps in the coverage of current programs that address aspects of the above concerns. Reasons are discussed for considering some familiar issues to be of lower importance than the above concerns, including railroad capital requirements, equipment availability, abandonment policy and sabotage, eminent domain for slurry pipelines, competition for barges at harvest time and potential impacts of the Clean Air Act amendments

Electric Power Interruption Cost Estimates for Individual Industries, Sectors, and U.S. Economy

During the last 20 years, utilities and researchers have begun to understand the value in the collection and analysis of interruption cost data. The continued investigation of the monetary impact of power outages will facilitate the advancement of the analytical methods used to measure the costs and benefits from the perspective of the energy consumer. More in-depth analysis may be warranted because of the privatization and deregulation of power utilities, price instability in certain regions of the U.S. and the continued evolution of alternative auxiliary power systems

LNG annotated bibliography

This document updates the bibliography published in Liquefied Gaseous Fuels Safety and Environmental Control Assessment Program: third status report (PNL-4172) and is a complete listing of literature reviewed and reported under the LNG Technical Surveillance Task. The bibliography is organized alphabetically by author

Fort Lewis electric energy baseline and efficiency resource assessment

The mission of the US Department of Energy (DOE) Federal Energy Management Program (FEMP) is to lead the improvement of energy efficiency and fuel flexibility within the federal sector. Through Pacific Northwest Laboratory, FEMP is developing a fuel-neutral approach for identifying, evaluating, and acquiring all cost-effective energy projects at federal installations. In this report, we describe PNL's assessment of the electric energy efficiency resource potential at Fort Lewis (near Tacoma, WA). Through this assessment, we developed an estimate of the electricity use baseline and efficiency improvement potential for major sectors and end uses at the Fort. Developing the baseline was essential to segment the end uses that are targets for broad-based efficiency improvement programs and to provide TPU with the basis for its proposal to Bonneville. An estimate of the efficiency resource is presented to reflect the available quantity of resource for three electricity price ranges. The baseline and efficiency resource estimates did not identify all possible areas of opportunity, but instead identified the majority of the resource; areas of additional opportunity are noted, to encourage further effort. 2 figs., 2 tabs

Fort Lewis electric energy baseline and efficiency resource assessment

In support of the US DOE Federal Energy Management Program, the Pacific Northwest Laboratory is developing a fuel-neutral approach for identifying, evaluating, and acquiring all cost-effective energy projects at federal installations. Fort Lewis, a US Army installation near Tacoma, Washington, was selected as the pilot site for developing this approach. This site was chosen in conjunction with the interests of the Bonneville Power Administration to develop programs for its federal sector customers and the Army Forces Command to develop an in-house program to upgrade the energy efficiency of its installations. This report documents the electricity assessment portion of the approach, providing an estimate of the electricity use baseline and efficiency improvement potential for major sectors and end uses at the Fort. Although the assessment did not identify all possible efficiency improvement opportunities, it is estimated that electricity use can be reduced by at least 20% cost-effectively at the $0.045/kWh marginal cost of electricity in the Pacific Northwest. 12 refs., 3 figs., 7 tabs

Pacific Northwest GridWise™ Testbed Demonstration Projects; Part I. Olympic Peninsula Project

This report describes the implementation and results of a field demonstration wherein residential electric water heaters and thermostats, commercial building space conditioning, municipal water pump loads, and several distributed generators were coordinated to manage constrained feeder electrical distribution through the two-way communication of load status and electric price signals. The field demonstration took place in Washington and Oregon and was paid for by the U.S. Department of Energy and several northwest utilities. Price is found to be an effective control signal for managing transmission or distribution congestion. Real-time signals at 5-minute intervals are shown to shift controlled load in time. The behaviors of customers and their responses under fixed, time-of-use, and real-time price contracts are compared. Peak loads are effectively reduced on the experimental feeder. A novel application of portfolio theory is applied to the selection of an optimal mix of customer contract types

Environmental concerns influencing the future development of energy material transportation systems: the year 2000 study

This paper presents results of studies conducted to assess the potentially longer-range problems which could hinder the future development of safe and environmentally-acceptable energy material transportation systems. The purpose of this effort is to recommend appropriate action that contributes to the anticipatory management of possible future problems before they can have serious effects on the adequacy or acceptability of the system. Most significant future concerns in energy material transportation relate to potential institutional, legal, political and social problems. Environmental issues are involved in many of these concerns. Selected environmental concerns are discussed that may influence the future development of transportation systems for fossil and nuclear energy materials during the balance of this century. A distinction between potentially real and perceived concerns is made to emphasize basic differences in the recommended approach to solutions of the respective type of potential problem