As a market segment for solar photovoltaic (PV) adoption, new homes have a number of attractive attributes. Homebuyers can easily roll the cost of the PV system into their mortgage and, with rebates or other financial incentives, potentially realize an immediate net positive cash flow from the investment. PV system performance can be optimized by taking roof orientation, shading, and other structural factors into account in the design of new homes. Building-integrated photovoltaics (BIPV), which are subject to fewer aesthetic concerns than traditional, rack-mounted systems, are well-suited to new construction applications. In large new residential developments, costs can be reduced through bulk purchases and scale economies in system design and installation. Finally, the ability to install PV as a standard feature in new developments - like common household appliances - creates an opportunity to circumvent the high transaction costs and other barriers typically confronted when each individual homeowner must make a distinct PV purchase decision.

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A new experimental technique to study crystallographic slip system activity in metallic single crystals deformed under a condition of uniaxial stress is applied to study the behavior of Zn single crystals. The experimental apparatus allows essentially unconstrained shape change of inherently anisotropic materials under a condition of uniaxial stress by allowing 3 translational and 3 rotational degrees of freedom during compression; hence we have named the experiment 6 degrees of freedom (6DOF). The experiments also utilize a 3-D digital image correlation system to measure full-field displacement fields, which are used to calculate strain and make direct observations of slip system activity. We show that the experimental results associated with a pristine zinc single crystal are precisely consistent with the theoretical predicted shape change (sample distortion) assuming that the most favored slip system on the basal plane is the only one that is active. Another experiment was performed on a processed and annealed Zn single crystal to investigate slip that is inconsistent with the critical resolved shear stress (CRSS) theory. These experiments on zinc illustrate the ability of the 6DOF experiment, together with image correlation (IC) data, to measure slip system activity with a high degree of fidelity.

To detect and quantify subtle surface CO2 leakage signals, we present a strategy that combines measurements of CO2 fluxes or concentrations in the near-surface environment with an algorithm that enhances temporally- and spatially-correlated leakage signals while suppressing random background noise. The algorithm consists of a filter that highlights spatial coherence in the leakage signal, and temporal stacking (averaging) that reduces noise from temporally uncorrelated background fluxes/concentrations. We assess the performance of our strategy using synthetic data sets in which the surface leakage signal is either specified directly or calculated using flow and transport simulations of leakage source geometries one might expect to be present at sequestration sites. We estimate the number of measurements required to detect a potential CO2 leakage signal of given magnitude and area. Results show that given a rigorous field-sampling program, subtle CO2 leakage may be detected using the algorithm; however, leakage of very limited spatial extent or exceedingly small magnitude may be difficult to detect with a reasonable set of monitoring resources.

The main purpose of this paper is to present the current status of development of the Lead-cooled Fast Reactor (LFR) in Generation IV (GEN IV), including the European contribution, to identify needed R&D and to present the corresponding GEN IV International Forum (GIF) R&D plan [1] to support the future development and deployment of lead-cooled fast reactors. The approach of the GIF plan is to consider the research priorities of each member country in proposing an integrated, coordinated R&D program to achieve common objectives, while avoiding duplication of effort. The integrated plan recognizes two principal technology tracks: (1) a small, transportable system of 10-100 MWe size that features a very long refuelling interval, and (2) a larger-sized system rated at about 600 MWe, intended for central station power generation. This paper provides some details of the important European contributions to the development of the LFR. Sixteen European organizations have, in fact, taken the initiative to present to the European Commission the proposal for a Specific Targeted Research and Training Project (STREP) devoted to the development of a European Lead-cooled System, known as the ELSY project; two additional organizations from the US and Korea have joined the project. Consequently, ELSY will …

In order to understand the physical processes associated with fs-laser waveguide writing in glass, the effects of the laser repetition rate, the material composition and feature size were studied. The resulting material changes were observed by collecting Raman and fluorescence spectra with a confocal microscope. The guiding behavior of the waveguides was evaluated by measuring near field laser coupling profiles in combination with white light microscopy. Waveguides and Bragg gratings were fabricated in fused silica using pulse repetition rates from 1 kHz to 1 MHz and a wide range of scan speeds and pulse energies. Two types of fluorescence were detected in fused silica, depending on the fabrication conditions. Fluorescence from self trapped exciton (E{prime}{sub {delta}}) defects, centered at 550 nm, were dominant for conditions with low total doses, such as using a 1 kHz laser with a scan speed of 20 {micro}m/s and pulse energies less than 1 {micro}J. For higher doses a broad fluorescence band, centered at 650 nm, associated with non-bridging oxygen hole center (NBOHC) defects was observed. Far fewer NBOHC defects were formed with the 1 MHz laser than with the kHz lasers possibly due to annealing of the defects during writing. We also observed an …

As an energy carrier, electricity has no rival with regard to its environmental cleanliness, flexibility in interfacing with multiple production sources and end uses, and efficiency of delivery. In fact, the electric power grid was named ?the greatest engineering achievement of the 20th century? by the National Academy of Engineering. This grid, a technological marvel ingeniously knitted together from local networks growing out from cities and rural centers, may be the biggest and most complex artificial system ever built. However, the growing demand for electricity will soon challenge the grid beyond its capability, compromising its reliability through voltage fluctuations that crash digital electronics, brownouts that disable industrial processes and harm electrical equipment, and power failures like the North American blackout in 2003 and subsequent blackouts in London, Scandinavia, and Italy in the same year. The North American blackout affected 50 million people and caused approximately $6 billion in economic damage over the four days of its duration. Superconductivity offers powerful new opportunities for restoring the reliability of the power grid and increasing its capacity and efficiency. Superconductors are capable of carrying current without loss, making the parts of the grid they replace dramatically more efficient. Superconducting wires carry up to …

Early in FY04, the Advanced Nuclear Transformation Technology (ANTT) subcommittee of the Nuclear Energy Research Advisory Committee (NERAC) requested a report on repository benefits for recycling of key transuranics in existing light water-cooled reactors (LWRs). The ANTT reviewers specifically requested a quantification of how such a campaign would impact (improve) the achievable loading of nuclear waste in the Yucca Mountain facility. The request stipulated that the transuranics be separated from commercial spent nuclear fuel (CSNF) and recycled a finite number of times in LWR-compatible fuel forms. The spent fuel remaining at the end of the recycling campaign, as well as all other nuclear waste generated by spent fuel reprocessing, would be permanently disposed in a geologic repository. In response, two reports have been prepared and distributed as deliverables for the AFCI program. Reference 1 provides the final report which addresses the original ANTT sub-committee request. Plutonium, neptunium, and americium recycling strategies in assemblies fabricated from mixed-oxide (MOX), CORAIL (heterogeneous UO{sub 2} and MOX), and inert-matrix fuel (IMF) forms were evaluated; the focus of the report is the time-dependent thermal response of the repository to a given loading of nuclear waste in the storage tunnels (drifts), as well as a quantification …

The methods and interim results from a testing program to quantify hydrogen effects on mechanical properties of carbon steel pipeline and pipeline weld materials are provided. The scope is carbon steels commonly used for natural gas pipelines in the United States that are candidates for hydrogen service in the hydrogen economy. The mechanical test results will be applied in future analyses to evaluate service life of the pipelines. The results are also envisioned to be part of the bases for construction codes and structural integrity demonstrations for hydrogen service pipeline and vessels. Tensile properties of one type of steel (A106 Grade B) in base metal, welded and heat affected zone conditions were tested at room temperature in air and high pressure (1500 psig) hydrogen. A general reduction in the materials ability to plastically deform was noted in this material when specimens were tested in 1500 psig hydrogen. Furthermore, the primary mode of fracture was changed from ductile rupture in air to cleavage with secondary tearing in hydrogen. The mechanical test program will continue with tests to quantify the fracture behavior in terms of J-R curves for these materials at air and hydrogen pressure conditions.

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U.S. Department of Energy (DOE) has monitored groundwater on the Hanford Site since the 1940s to help determine what chemical and radiological contaminants have made their way into the groundwater. As regulatory requirements for monitoring increased in the 1980s, there began to be some overlap between various programs. DOE established the Groundwater Performance Assessment Project (groundwater project) in 1996 to ensure protection of the public and the environment while improving the efficiency of monitoring activities. The groundwater project is designed to support all groundwater monitoring needs at the site, eliminate redundant sampling and analysis, and establish a cost-effective hierarchy for groundwater monitoring activities. This document provides the quality assurance guidelines that will be followed by the groundwater project. This QA Plan is based on the QA requirements of DOE Order 414.1C, Quality Assurance, and 10 CFR 830, Subpart A--General Provisions/Quality Assurance Requirements as delineated in Pacific Northwest National Laboratory’s Standards-Based Management System. In addition, the groundwater project is subject to the Environmental Protection Agency (EPA) Requirements for Quality Assurance Project Plans (EPA/240/B-01/003, QA/R-5). The groundwater project has determined that the Hanford Analytical Services Quality Assurance Requirements Documents (HASQARD, DOE/RL-96-68) apply to portions of this project and to the subcontractors. HASQARD …