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A system analysis has been performed to assess the efficiency and carbon utilization of a nuclear-assisted coal gasification process. The nuclear reactor is a high-temperature helium-cooled reactor that is used primarily to provide power for hydrogen production via high-temperature electrolysis. The supplemental hydrogen is mixed with the outlet stream from an oxygen-blown coal gasifier to produce a hydrogen-rich gas mixture, allowing most of the carbon dioxide to be converted into carbon monoxide, with enough excess hydrogen to produce a syngas product stream with a hydrogen/carbon monoxide molar ratio of about 2:1. Oxygen for the gasifier is also provided by the high-temperature electrolysis process. The results of the analysis predict 90.5% carbon utilization with a syngas production efficiency (defined as the ratio of the heating value of the produced syngas to the sum of the heating value of the coal plus the high-temperature reactor heat input) of 64.4% at a gasifier temperature of 1866 K for the high-moisture-content lignite coal considered. Usage of lower moisture coals such as bituminous can yield carbon utilization approaching 100% and 70% syngas production efficiency.

Accelerated market penetration of plug-in electric vehicles and deployment of grid-connected energy storage are restricted by the high cost of lithium-ion batteries. Research, development, and manufacturing are underway to lower material costs, enhance process efficiencies, and increase production volumes. A fraction of the battery cost may be recovered after vehicular service by reusing the battery where it may have sufficient performance for other energy-storage applications. By extracting post-vehicle additional services and revenue from the battery, the total lifetime value of the battery is increased. The overall cost of energy-storage solutions for both primary (automotive) and secondary (grid) customer could be decreased. This techno-economic analysis of battery second use considers effects of battery degradation in both automotive and grid service, repurposing costs, balance-of-system costs, the value of aggregated energy-storage to commercial and industrial end users, and competitive technology. Batteries from plug-in electric vehicles can economically be used to serve the power quality and reliability needs of commercial and industrial end users. However, the value to the automotive battery owner is small (e.g., $20-$100/kWh) as declining future battery costs and other factors strongly affect salvage value. Repurposed automotive battery prices may range from $38/kWh to $132/kWh.

This paper discusses key design and development issues in utilizing coal and other solid fuels in gas turbines. These fuels may be burned in raw form or processed to produce liquids or gases in more or less refined forms. The use of such fuels in gas turbines requires resolution of technology issues which are of little or no consequence for conventional natural gas and refined oil fuels. For coal, these issues are primarily related to the solid form in which coal is naturally found and its high ash and contaminant levels. Biomass presents another set of issues similar to those of coal. Among the key areas discussed are effects of ash and contaminant level on deposition, corrosion, and erosion of turbine hot parts, with particular emphasis on deposition effects.

Large loading events on wind turbine rotor blades are often associated with transient bursts of coherent turbulent energy in the turbine inflow. These coherent turbulent structures are identified as peaks in the three-dimensional, instantaneous, turbulent shearing stress field. Such organized inflow structures and the accompanying rotor aeroelastic responses typically have time scales of only a few seconds and therefore do not lend themselves for analysis by conventional Fourier spectral techniques. Time-frequency analysis (and wavelet analysis in particular) offers the ability to more closely study the spectral decomposition of short period events such as the interaction of coherent turbulence with a moving rotor blade. In this paper, the authors discuss the initial progress in the application of time-frequency analysis techniques to the decomposition and interpretation of turbulence/rotor interaction. The authors discuss the results of applying both the continuous and discrete wavelet transforms for their application. Several examples are given of the techniques applied to both observed turbulence and turbine responses and those generated using numerical simulations. They found that the presence of coherent turbulent structures, as revealed by the inflow Reynolds stress field, is a major contributor to large load excursions. These bursts of coherent turbulent energy induce a broadband aeroelastic response in the turbine rotor as it passes through them.

The Product Development Team (PD) in the US Environmental Protection Agency's ENERGY STAR Labeling Program fuels the long-term market transformation process by delivering new specifications. PD's goal is to expand the reach and visibility of ENERGY STAR as well as the market for new energy-efficient products. As of 2002, PD has launched nine new ENERGY STAR specifications and continues to evaluate new program opportunities. To evaluate the ENERGY STAR potential for a diverse group of products, PD prepared a framework for developing new and updating existing specifications that rationalizes new product opportunities and draws upon the expertise and resources of other stakeholders. Manufacturers and stakeholders have a vested interest in understanding how ENERGY STAR products are selected for labeling. In this article, we explore in depth PD's process and also provide two case studies that illustrate the application of PD's framework. After 3 years of implementation, several lessons learned have emerged. Manufacturers are increasingly inquiring as to why a product is/is not labeled. Careful application of the framework allows PD to justify program decisions. PD increasingly recognizes that each industry has unique market and product characteristics that can require reconciliation with the guidelines of the ENERGY STAR program. Careful application of the framework identifies where reconciliation is needed to preserve the program integrity and justify decisions. Finally, to date, the application of the framework has enabled PD to navigate through complex product issues and make consistent specification development decisions.

MERCURY is a modern, parallel, general-purpose Monte Carlo code being developed at the Lawrence Livermore National Laboratory. Recently, a radiographic capability has been added. MERCURY can create...

Theoretical studies have demonstrated that the energy transfer between a hot an cold body at close spacing (on the order of the radiation wavelength) can greatly exceed the limit for black body radiation (i.e. Power=σT4). This effect, due to the coupling of evanescent fields, presents an attractive option for thermo-photovoltaic (TPV) applications (assuming the considerable technical challenges can be overcome). The magnitude of the enhanced energy transfer depends on the optical properties of the hot and cold bodies as characterized by the dielectric functions of the respective materials. The present study considers five different situations as specified by the materials choices for the hot/cold sides: metal/metal, metal/insulator, metal/semiconductor, insulator/insulator, and semiconductor/semiconductor. For each situation, the dielectric functions are specified by typical models. An increase in energy transfer (relative to the black body law) is found for all situations considered, for separations less...

Three instruments for measuring local velocities in liquid-metal MHD experiments for fusion blanket applications are being evaluated. The devices are used in room-temperature NaK experiments to measure three-dimensional flow field patterns anticipated in complex blanket geometries. Hot film anemometry, a standard technique in ordinary fluids, is being used, as well as two developmental devices. One is called the Liquid Metal Electromagnetic Velocity Instrument (LEVI), and performs essentially as a local dc electromagnetic flow meter. The third device, a Thermal Transient Anemometer (TTA) is a rugged, yet relatively simple device, which measures local velocity through the mechanism of convective heat transfer, in some ways similar to hot-film anemometry. Results are presented showing the kinds of data collected this far with each instrument. Measurements include both local velocity measurements and some preliminary frequency analyses of the fluctuating signals from both a hot-film sensor and the LEVI device.