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At least 1,297 records · Page 72

Scanning ARM Cloud Radar—Advanced—Velocity Azimuth Display Value-Added Product

Spatial distribution of horizontal winds is an important meteorological property to understand mesoscale and cloud scale dynamics of cloud and precipitation systems. The most popular wind measurement is performed by soundings. The sounding observation is generally conducted 1-4 times per day, which may not be enough to observe detailed in-cloud structure. Doppler weather and cloud radars can perform frequent measurements of radial velocities of cloud/precipitation particles in clouds. The weather radar community has historically used the Velocity-Azimuth Display (VAD) technique to retrieve in-cloud wind properties (direction and speed) from radial velocity (e.g., Lhermitte and Atlas, 1961). The U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility’s Ka- and W-band Scanning ARM Cloud Radars (SACRs) collect volume observations of mean Doppler velocity with horizon-to-horizon range height indicator (HSRHI) scans every 30-60 minutes. The SACR ADVanced Velocity-Azimuth Display (SACR-ADV-VAD) Value-Added Product (VAP) extends the VAD technique to cloud radar observations. The VAP provides time series of vertical profiles of in-cloud wind fields at higher temporal and vertical resolutions, which can augment sounding wind measurements.

47 OTHER INSTRUMENTATION↗

Property Values Associated with the Failure of Individual Links in a System with Multiple Weak and Strong Links.

Representations are developed and illustrated for the distribution of link property values at the time of link failure in the presence of aleatory uncertainty in link properties. The following topics are considered: (i) defining properties for weak links and strong links, (ii) cumulative distribution functions (CDFs) for link failure time, (iii) integral-based derivation of CDFs for link property at time of link failure, (iv) sampling-based approximation of CDFs for link property at time of link failure, (v) verification of integral-based and sampling-based determinations of CDFs for link property at time of link failure, (vi) distributions of link properties conditional on time of link failure, and (vii) equivalence of two different integral-based derivations of CDFs for link property at time of link failure.

97 MATHEMATICS AND COMPUTING↗

Possible reason for the numerical value of the fine-structure constant

A simple picture of the electron emerges if there is a cross section of πλ 2 for vacuum virtual photons to stimulate an isolated electron to emit an additional virtual photon. This reaction mechanism leads to the storage of the rest-mass energy in the surrounding cloud of virtual photons. The Lamb shift can be obtained if one out of every 1/α of the stimulated emissions is preceded by the absorption and re-emission of the incident vacuum virtual photon including the corresponding electron recoil. This suggests a “doorway” cross section of απλ 2 plays a key role in some QED processes. Additional support for this suggestion is obtained via a simple semi-classical picture of Compton scattering. Several speculative semi-classical reaction mechanism choices, including near-field effects, give the anomalous magnetic moment of the free electron. These choices are partially justified by their ability to give the magnetic moment of electrons in hydrogen-like atoms as a function of the atomic number of the corresponding nucleus, close to the correct result. The stimulated-emission process used to obtain the rest-mass energy allows for the possibility that stimulated virtual photons can be exchanged between an electron pair. This exchange can be used to estimate a repulsive force between electrons, and thus allows for a calculation of the fine-structure constant. A result near to the experimental value is obtained with minor modifications to the assumptions that give the rest mass, Lamb shift, and anomalous magnetic moment of the electron. Additional studies are required to confirm or negate the suggestions made here.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

IEA Wind TCP Task 26: Impacts of Wind Turbine Technology on the System Value of Wind in Europe

This report analyzes the impact of different land-based wind turbine designs on grid integration and related system value and cost. This topic has been studied in a number of previous publications, showing the potential benefits of wind turbine technologies that feature higher capacity factors. Building on the existing literature, this study aims to quantify the effects of different land-based wind turbine designs in the context of a projection of the European power system to 2030. This study contributes with insights on the quantitative effects in a likely European market setup, taking into account the effect of existing infrastructure on both existing conventional and renewable generation capacities. Furthermore, the market effects are put into perspective by comparing cost estimates for deploying different types of turbine design. Although the study focuses on Europe, similar considerations and results can be applied to other power systems with high wind penetration.

17 WIND ENERGY↗

Estimating the Value of Improved Distributed Photovoltaic Adoption Forecasts for Utility Resource Planning

Misforecasting the adoption of customer-owned distributed photovoltaics (DPV) can have operational and financial implications for utilities; forecasting capabilities can be improved, but generally at a cost. This paper informs this decision-space by using a suite of models to explore the capacity expansion and operation of the Western Interconnection over a 15-year period across a wide range of DPV growth rates and misforecast severities. The system costs under a misforecast are compared against the costs under a perfect forecast, to quantify the costs of misforecasting. Using a simplified probabilistic method applied to these modeling results, an analyst can make a first-order estimate of the financial benefit of improving a utility’s forecasting capabilities, and thus be better informed about whether to make such an investment. For example, under our base assumptions, a utility with 10 TWh per year of retail electric sales who initially estimates that DPV growth could range from 2% to 7.5% of total generation over the next 15 years could expect total present-value savings of approximately $4 million if they could reduce the severity of misforecasting to within ±25%. Utility resource planners can compare those savings against the costs needed to achieve that level of precision, to guide their decision on whether to make an investment in tools or resources.

14 SOLAR ENERGY↗

Development and Comparison of Purgeable Mercury Values in SRR Samples Measured by SRNL and Eurofins FGS

Savannah River Remediation (SRR) requested the development of mercury speciation capabilities at the Savannah River National Laboratory (SRNL) to support the Liquid Waste Operations at SRS. As part of that method development, SRR requested that SRNL Analytical Development (AD) compare their results with those obtained from their outside contract laboratory, Eurofins Frontier Global Sciences (FGS). This document reports on this method development work as well as the comparative analyses conducted between the two laboratories. Development, optimization, and validation were undertaken at SRNL to produce a method for the species-specific analysis of dissolved gaseous mercury (DGM) in samples from SRR. It was determined that DGM present in SRR samples represented a combination of various soluble and volatile mercury species- and is thus referred to in this document as purgeable mercury. A method has been developed and analytically validated for the analysis of purgeable mercury in caustic nuclear waste. Using multivariate optimization method, purge flow rate was determined to be highly correlated with increased response (p=0.023). Total recovery of spiked purgeable mercury from deionized water was 99.4 ±10.6% and 91.6 ±14.9% from spiked high-activity tank waste samples. Calibration, by external calibration and standard addition calibration, maintained a mean accuracy of 101 ±5% and 99.9 ±1.7%, respectively. This method represents a decrease in sample handling and processing over currently standard methods and represents a more amenable method for purgeable mercury analysis in liquid nuclear waste.1 An interlaboratory comparison was performed between SRNL and Eurofins FGS in the co-analysis of three quarterly Tank 50 samples. Two samples demonstrated no statistically significant difference (p=0.271, p=0.0811), with one sample biased 30% low to a statistically significant degree (p=0.0432). Large mean uncertainty was present in the results reported by both laboratories (±15% and 40% from SRNL and Eurofins), with no significant difference observed in uncertainty (p=0.934). Across all co-analyzed samples, no significantly difference was observed in precision (p=0.205) or reported values (p=0.352) between SRNL and Eurofins. These results indicate that SRNL-AD may provide data to the customer of statistically similar quality.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Optimizing the Energy Usage and Cognitive Value of Extreme-Scale Data-Analysis Approaches

This report serves as a record that we have successfully completed work on the proposal Optimizing the Energy Usage and Cognitive Value of Extreme Scale Analysis Approaches, or, more succinctly, ECX. This includes successful completion of all three phases of the project, findings as summarized below, strong publications across the fields represented in the proposal, and a set of artifacts (code, websites, and other documentation) available to the public. In total, the results of this project represent significant findings in each domain, and a toolkit that will allow the community to engage with this work, advancing it and contributing to it in the years ahead. They also form the basis for a successfully funded follow-on project. This executive summary presents findings, tools and publications resulting from the ECX project. The balance of the report then provides more detail on these results.

97 MATHEMATICS AND COMPUTING↗

Value Accrual to Customers, Installers, and Financiers in Third-Party Owned Solar PV Markets

Beyond the Federal Investment Tax Credit, the two primary financial incentives provided by residential solar photovoltaic (PV) systems are electricity bill savings and state and local government incentives. Using transaction-level data on third-party owned systems from 2012-2015, we estimate how value associated with these incentives are passed along the installer-financier-consumer supply chain in the third-party owned market. Our analysis finds evidence of financial incentive pass-through to system prices and customer payments with respect to both types of incentives. Moreover, we document differences in the levels of pass-through for different contract types: total pass-through to customer payments for both types of incentives is greater for PPAs than for UFOs. We find some evidence that pass-through rates to customer payments for PPAs change with market concentration. Finally, we illustrate that the magnitude of estimated pass-through changes for PPAs if we account for simultaneity between system prices and customer payments.

14 SOLAR ENERGY↗

Models and methods for assessing the value of HVDC adn MVDC technologies in modern power grids (Annual Report, Executive Summary)

Evolution of today’s predominantly alternating current (ac) transmission grid in to mixed ac transmission – high-voltage direct current (HVdc) systems is expected with the decreasing costs of and advancements in power electronics technologies. The recent technological advancements include the development of more efficient and compact voltage source converters (VSCs) that can provide fast response. Because of their controllability and fast response, HVdc systems provide the ability to enhance reliability of the ac transmission grid through frequency support, voltage control, and congestion relief. The HVdc systems can also provide other ancillary services to enhance the economics and reliability of the ac transmission grids, and to optimize their performance. The tools, models, and methods developed to evaluate their benefits will be key enablers to understanding the value proposition introduced by the fast-acting HVdc systems. The main motivation of this work was to develop models and methods to explore and quantify the technical and economic benefits of HVdc systems and fast response VSC technologies in the future grid of United States. The models and methods explore the benefits of HVdc systems through provision of controlled active/reactive power and fast response. The fast response can provide much-needed multiobjective services to the grid (e.g., frequency response, voltage control) while moving blocks of energy. The models and methods can be applied to study other power electronics technologies and scenarios such as those undertaken in ongoing studies led by the North American Electric Reliability Corporation (NERC) Inverter-based Resource Performance Task Force (IRPTF). The IRPTF studies identify the problems associated with power electronics-based technologies as they are integrated in to the bulk power system (or the ac transmission system).

24 POWER TRANSMISSION AND DISTRIBUTION↗

Maximum Concentration Values Review for Use in NUCON Vapor Abatement Unit Testing

Exponent has recommended that “high inlet spike” concentrations be verified for accuracy regarding their representation of the maximum measured headspace concentrations for tanks at Hanford. Exponent further recommended that “high inlet spike” concentrations of chemicals of potential concern (COPCs) be inclusive of surrogate COPCs. In the initial analysis (Rev. A Test Plan), only analytical results from the Site-Wide Industrial Hygiene Database (SWIHD) were used. The reason for this initial decision was a concern about Washington River Protection Solutions (WRPS) taking responsibility for results that were not produced during their contract tenure. As a result of Exponent’s comments, WRPS verified the “high inlet spike” values for accuracy against the data for single-shell tanks in all the historical databases, not only SWIHD. Measurements made prior to interim waste stabilization or waste retrieval were not considered in the verification of maximum measured concentrations as they are not representative of current tank farm conditions. Data for surrogate COPCs were also considered in determining the “high inlet spike” concentrations. Table S.1 shows the newly evaluated concentrations (COPC and surrogate). The original and revised test conditions are also shown with changes indicated by red text.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Optimizing the Energy Usage and Cognitive Value of Extreme-Scale Data-Analysis Approaches (Final Report)

This report serves as a record that we have successfully completed work on the proposal Optimizing the Energy Usage and Cognitive Value of Extreme Scale Analysis Approaches, or, more succinctly, ECX. This includes successful completion of all three phases of the project, findings as summarized below, strong publications across the fields represented in the proposal, and a set of artifacts (code, websites, and other documentation) available to the public. In total, the results of this project represent significant findings in each domain, and a toolkit that will allow the community to engage with this work, advancing it and contributing to it in the years ahead. They also form the basis for a successfully funded follow-on project. This executive summary presents findings, tools and publications resulting from the ECX project. The balance of the report then provides more detail on these results.

97 MATHEMATICS AND COMPUTING↗

Aerosol and Cloud Optical Properties from the ARM Raman Lidars: The Feature Detection and Extinction (RLPROF-FEX) Value-Added Product

Aerosols and their interactions and influence on clouds are among the main sources of uncertainties in radiative direct and indirect forcing (IPCC 2013). Continuous height-resolved measurements of cloud and aerosol optical properties are needed to reduce these uncertainties. Here we describe the Raman Lidar Profiles – Feature detection and Extinction (RLPROF-FEX) Value-Added Product (VAP) derived using Raman lidar data at multiple U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) user facility sites. RLPROF-FEX provides estimates of extinction, backscatter, and depolarization using the algorithm described by Thorsen et al. 2015 and Thorsen and Fu 2015. This document provides a description of the FEX algorithm, its input and output data, and related details about the Raman lidar (RL) system.

54 ENVIRONMENTAL SCIENCES↗

Models and Methods for Assessing the Value of HVDC and MVDC Technologies in Mondern Power Grids

Evolution of today’s predominantly alternating current (ac) transmission grid in to mixed ac transmission – high-voltage direct current (HVdc) systems is expected with the decreasing costs of and advancements in power electronics technologies. The recent technological advancements include the development of more efficient and compact voltage source converters (VSCs) that can provide fast response. Because of their controllability and fast response, HVdc systems provide the ability to enhance reliability of the ac transmission grid through frequency support, voltage control, and congestion relief. The HVdc systems can also provide other ancillary services to enhance the economics and reliability of the ac transmission grids, and to optimize their performance. The tools, models, and methods developed to evaluate their benefits will be key enablers to understanding the value proposition introduced by the fast-acting HVdc systems.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Oklahoma Mesonet Soil Moisture (OKMSOIL) Value-Added Product Report

Land surface and subsurface state characteristics (e.g., soil moisture) are critical measurements for ongoing weather and climate analyses of land-atmospheric interactions and processes. Knowledge of the variation in soil moisture across the U.S. Department of Energy Atmospheric Radiation Measurement (ARM) user facility’s Southern Great Plains (SGP) observatory domain is anticipated as a key quantity for assessing the potential impact of these interactions. This Oklahoma Mesonet Soil Moisture (OKMSOIL) value-added product (VAP) has been developed in response to growing demand for delivering a long-term measurement record of soil moisture (over an extended area) for such land-atmospheric studies. The Oklahoma Mesonet (OKM) started as a joint project between Oklahoma State University and the University of Oklahoma (Brock 1995). The OKM currently operates over 100 surface Mesonet stations across the state of Oklahoma, with an operational data record that extends into the early 1990s. This dense network of atmospheric and surface state instrumentation enables representation of land surface/subsurface conditions over this region and extended record. Algorithms introduced by previous Oklahoma Mesonet activities (e.g., Scott et al. 2013) are implemented in this documented OKMSOIL VAP to derive a key soil moisture quantity, the volumetric water content (volume of water per volume of soil in units, cm 3 /cm 3 ), from measurements of soil matric potential. These algorithms use a soil hydraulic parameter database (Meso-Soil Database) provided by the Oklahoma Mesonet scientists to estimate this quantity and several additional Mesonet station/sample details.

54 ENVIRONMENTAL SCIENCES↗

Ka-Band ARM Zenith Radar Corrections (KAZRCOR, KAZRCFRCOR) Value-Added Products

The Ka-Band Atmospheric Radiation Measurement (ARM) Zenith Radar Corrections (KAZRCOR) and KA-Band ARM Zenith Radar CF-Radial, Corrected (KAZRCFRCOR) value-added products (VAPs) perform several corrections to the ingested KAZR moments and also create a significant detection mask for each radar mode. The VAPs compute gaseous attenuation as a function of time and radial distance from the radar antenna, based on ambient meteorological observations, and correct observed reflectivities for that effect. Mean Doppler velocities are dealiased to correct velocities whose magnitudes exceed the radar’s Nyquist velocity. Input KAZR data fields are passed through to the KAZRCOR or KAZRCFRCOR output files, in their native time and range coordinates. Complementary corrected reflectivity and velocity fields are provided, along with a mask of significant detections and a number of data quality flags. This report covers the KAZRCOR VAP as applied to the original KAZR radars and the upgraded KAZR2 radars. Originally, prior to late 2019, there were two separate code bases for the different radar versions. Following the harmonization of KAZR and KAZR2 data formats in 2019, only a single code base is required. The new combined KAZR and KAZR2 code base is called the KAZRCFRCOR VAP. The ‘cfr portion of the VAP name refers to the Radial Climate and Forecasting data format standards that are used in these data sets. Throughout this report, references to ‘KAZRCOR’ should be taken to apply to the ‘KAZRCFRCOR’ VAP as well unless there is an explicit statement to the contrary.

54 ENVIRONMENTAL SCIENCES↗

Point Cloud of Cloud Points (PCCP) Value-Added Product Report

In this report, we refer to a pair of cameras that capture synchronized pictures with overlapping fields of view (FOV) as a stereo pair. Each stereo pair independently performs a stereo reconstruction of cloud points. Currently, there are three U.S. Department of Energy Atmospheric Radiation Measurement (ARM) user facility stereo pairs (six cameras in total) positioned around the Southern Great Plains (SGP) observatory’s Central Facility (CF; Romps and Oktem 2017). Time-synchronized pictures from the two cameras in a stereo pair can be paired together to obtain a three-dimensional (3D) reconstruction of feature points by triangulation. This document explains how we use ARM stereo cameras and stereophotogrammetric principles to generate the Point Cloud of Cloud Points (PCCP) Value-Added Product (VAP). The PCCP VAP is essentially a set of 3D positions representing the locations of cloud features in the sky. Thousands of cloud features can be reconstructed instantly in each stereo pair's FOV, which covers an area of tens of square kilometers. Cloud base and cloud top heights can be extracted from the PCCP product.

54 ENVIRONMENTAL SCIENCES↗