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DOE OSTI2020

Shield Design for 50 kW Three-Phase Wireless Charging System

In this paper, magnetic field emissions (MFE) from a 50 kW bipolar coil-based three-phase wireless charging system (WCS) is investigated. Then, a shield design is proposed to suppress the MFE below the safety limit identified by the International Commission of Non-Ionized Radiation Protection (ICNIRP) guidelines. Bipolar coil-based three-phase (3φ) WCSs provide extremely high power-density; therefore, the 3φ WCSs are highly promising for high-power fast-wireless-charging of the electric vehicles. For the high-power EV application, it is a critical challenge to design a shield to suppress the MFE below the safety limit. The traditional aluminum shield is found ineffective for the bipolar 3φ-WCS. The proposed shield is designed with high-permeability magnetic material, i.e. ferrite, nanocrystalline material, etc. The proposed shield is simulated in finite element analysis (FEA) and the FEA results show that the proposed magnetic shield effectively suppresses the magnetic field emission below the ICNIRP limit. The generalized design of the proposed shield can be used for even higher power bipolar coil based WCSs.

Mohammad, Mostak↗

DOE OSTI2017

Model Reduction for Fast Assessment of Grid Impact of High Penetration PV

A key challenge in properly analyzing the impact of solar photovoltaics (PV) during planning, interconnection and operation in the distribution grid is computational complexity. Such studies require the use of Quasi-Steady-Time-Series (QSTS) power flow to capture the complex interaction of PV with voltage regulating equipment and protection devices and a large number of scenario studies are needed to capture location specific constraints and uncertainties. In addition, a typical distribution feeder can have thousands of nodes and there can be thousands of such feeders in a given utility system. To solve this problem, a new and systematic method for distribution network reduction is proposed. The objective is to reduce the size of distribution systems by more than 80% while preserving the accuracy of power flow results. To this end, an extended Ward-equivalent method has been proposed to create an equivalent circuit. Moreover, load and PV aggregation based on the backward sweep method has been developed to further simplify the feeder. The proposed method is tested with a modified IEEE 123-node distribution test system. The simulation results demonstrate the high efficiency and accuracy of the proposed approach for distribution network reduction.

reduced order systems, load flow, load modeling, v↗

DOE OSTI2015

WE-E-304-02: Implementing SBRT Protocols: A NRG CIRO Perspective

SBRT is having a dramatic impact on radiation therapy of early-stage, locally advanced cancers. A number of national protocols have been and are being developed to assess the clinical efficacy of SBRT for various anatomical sites, such as lung and spine. Physics credentialing for participating and implementation of trial protocols involve a broad spectrum of requirements from image guidance, motion management, to planning technology and dosimetric constrains. For radiation facilities that do not have extensive experiences in SBRT treatment and protocol credentialing, these complex processes of credentialing and implementation could be very challenging and, sometimes, may lead to ineffective even unsuccessful execution of these processes. In this proposal, we will provide comprehensive review of some current SBRT protocols, explain the requirements and their underline rationales, illustrate representative failed and successful experiences, related to SBRT credentialing, and discuss strategies for effective SBRT credentialing and implementation. Learning Objectives: Understand requirements and challenges of SBRT credentailing and implentation Discuss processes and strategies of effective SBRT credentailing Discuss practical considerations, potential pitfalls and solutions of SBRT implentation.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2015

WE-E-304-01: SBRT Credentialing: Understanding the Process From Inquiry to Approval

60 APPLIED LIFE SCIENCES↗

DOE OSTI2014

Noble Gas Concept Of Operation

The intent of this document is to provide the reader with an understanding of a general approach to performing the noble gas component of an On Site Inspection or OSI. The authors of this document recognize that owing to the wide range of scenarios that are possible for carrying out an underground nuclear explosion, the diverse sets of information that might be available to the inspection team initially and the potential range of political and physical constraints imposed during the inspection, a satisfactory prescriptive approach to carrying out the noble gas component of an OSI is unlikely. Rather, the authors intend only to aid the reader in understanding what a reasonable course of actions or responses may be as performed by an inspection team (IT) during a general OSI. If this document helps to inform the intuition of the reader about addressing the challenges resulting from the inevitable deviations from this general scenario, it will have achieved its intent.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2015

Biogas Opportunities Roadmap Progress Report

In support of the Obama Administration's Climate Action Plan, the U.S. Department of Energy, the U.S. Environmental Protection Agency, and U.S. Department of Agriculture jointly released the Biogas Opportunities Roadmap Progress Report, updating the federal government's progress to reduce methane emissions through biogas systems since the Biogas Opportunities Roadmap was completed by the three agencies in July 2014. The report highlights actions taken, outlines challenges and opportunities, and identifies next steps to the growth of a robust biogas industry.

09 BIOMASS FUELS↗

DOE OSTI2018

Cyberspace, Information Strategy and International Security (Workshop Summary)

In recent years, the Center for Global Security Research has hosted a number of events to inform strategic thought on key areas of concern to national security and laboratory planning. This was the first dedicated workshop that CGSR has hosted seeking to convene a community of experts around issues of cybersecurity and Internet governance as they pertain to national security. The goal of this work was to bridge policy, academic, military, technical and other expert communities that often have limited contact with each other’s concerns and specialized knowledge. This workshop brought together over 80 experts from government, military, national labs, academic institutions, think tanks, the private sector, and civil society and hailing from 10 countries. While focusing on the national security challenges and military strategy emerging in and through cyberspace, the workshop aimed to address the cross-cutting interests and concerns of different stakeholders in the development and future governance of cyberspace, including those of the private sector, and civilian publics. To this end, the first day of the workshop focused particularly on issues directly relevant to military strategy in the cyber domain, while the second day addressed questions bridging national security and military concerns and their connections to the domestic and international politics of Internet governance. Topics discussed included the evolving cyber strategies of the U.S., U.S. allies and potential adversaries, as well as the complex characteristics of the cyber domain, the potential for deterrence in or through cyberspace, the domain’s escalation risks, and the ways in which the “dual use” nature of much of the underlying technology of cyberspace connects actions in the domain with broader questions of global Internet governance. Issues of online disinformation and information warfare and the unique conceptual tensions and governance challenges posed by these forms of conflict were addressed. The workshop also examined the roles and interests of different stakeholders in addressing cybersecurity challenges, as well as the possibility of norms, international law, and other potential mechanisms of constraint.

97 MATHEMATICS AND COMPUTING↗

DOE OSTI2024

Portable Soft X-Ray Diagnostics for Transformative Fusion-Energy Concepts (Final Scientific/Technical Report)

A time-gated extreme-ultraviolet spectrometer was fielded on a transformative fusion-energy device, FuZE-Q at Zap Energy, Inc. (ZEI), a sheared-flow-stabilized z-pinch. Plasma emission spectra were collected in the 5–40 nm wavelength (30–250 eV) range. This was the first time a direct-vacuum-coupled, high-voltage, deposition-sensitive diagnostic was fielded on this type of dense-plasma fusion device. To overcome the special challenges of such a coupling, a unique, highly effective implementation was developed, with fast (10-ns risetime) pulsed high-voltage electronics and a multi-stage differential pumping system. This enabled the UNR spectrometer to collect three independently timed spectra per FuZE-Q shot while also protecting sensitive internal components. Analysis of line emission identified oxygen (N-, C-, B-, Be-, Li-, and He-like O), peaking in intensity shortly after maximum current (>500 kA). Spectral databases and collisional-radiative modeling have been used to identify impurities and estimate edge-plasma temperatures.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

DOE OSTI2025

PCOR partnership initiative to accelerate CCCUS deployment

The Plains CO 2 Reduction (PCOR) Partnership Initiative, led by the Energy & Environmental Research Center (EERC), was a 5-year collaborative effort under the U.S. Department of Energy’s Regional Initiative to Accelerate CCUS (carbon capture, utilization, and storage). With support from the University of Wyoming School of Energy Resources (UW SER), the University of Alaska Fairbanks Institute of Northern Engineering (UAF INE), and a broad network of public and private stakeholders, the program focused on overcoming regional challenges to CCUS across ten U.S. states and four Canadian provinces. This report summarizes the notable findings of the EERC and its collaborators through the 5-year PCOR Partnership Initiative phase. The EERC developed and demonstrated a risk-based area of review (AOR) workflow for U.S. Environmental Protection Agency Class VI carbon dioxide (CO 2 ) storage permitting.

01 COAL, LIGNITE, AND PEAT↗

DOE OSTI2015

LBNF Hadron Absorber: Mechanical Design and Analysis for 2.4MW Operation

Fermilab’s Long-Baseline Neutrino Facility (LBNF) requires an absorber, essentially a large beam dump consisting of actively cooled aluminum and steel blocks, at the end of the decay pipe to stop leftover beam particles and provide radiation protection to people and groundwater. At LBNF’s final beam power of 2.4 MW and assuming the worst case condition of a 204 m long helium filled decay pipe, the absorber is required to handle a heat load of about 750 kW. This results in significant thermal management challenges which have been mitigated by the addition of an aluminum ‘spoiler’ and ‘sculpting’ the central portion of the aluminum core blocks. These thermal effects induce structural stresses which can lead to fatigue and creep considerations. Various accident conditions are considered and safety systems are planned to monitor operation and any accident pulses. Results from these thermal and structural analyses will be presented as well as the mechanical design of the absorber. The design allows each of the core blocks to be remotely removed and replaced if necessary. A shielded remote handling structure is incorporated to hold the hadron monitor when it is removed from the beam.

Hartsell, B.↗

DOE OSTI2021

Defining a Use Case for the ADMS Test Bed: Fault Location, Isolation, and Service Restoration with Distributed Energy Resources: Preprint

Advanced distribution management systems (ADMS) integrate multiple enterprise-level functions into a single platform and offer advanced applications such as fault location, isolation, and service restoration (FLISR), to utilities to meet their operational needs for a modernized grid. These applications need to operate reliably even as distributed energy resource (DER) penetration increases on distribution systems. The ADMS test bed at the National Renewable Energy Laboratory offers utilities and vendors the opportunity to evaluate the performance of such advanced applications on distribution feeders of the future and to understand their potential benefits for a specific utility. This is done through defining use cases that address specific questions. This paper presents the definition of a use case on the performance of a commercially-available FLISR application on a feeder of an electric cooperative with DERs. Results from this use case will be disseminated to the electric utility and research community to improve understanding of the challenges and benefits that DERs present to ADMS applications and the operation of a modernized grid.

61 RADIATION PROTECTION AND DOSIMETRY↗

DOE OSTI2018

French Cigeo Operational Safety Options: The General Approach and Challenging Issues Towards the Licensing - 18051

After around 25 years of In view of the licensing application, two main milestones for safety are identified for Cigeo: a Safety Options Dossier 'DOS' early 2016 and the safety case to support Future License Application of Cigeo. The Safety Options was an opportunity for Andra to send in advance a first safety case to the French Safety Authority in order to stabilize the safety strategy, the safety requirements, the safety methods, key safety and design options, the list of safety scenarios that are selected and a preliminary 'bounding' impact. The paper describes the approach applied for the operating safety options and the main concluding aspects as well as the challenging issues towards the licensing. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2019

Progress in Addressing Workers' Concerns Related to Chemical Vapors at the Hanford Site - 19054

Washington River Protections Solutions, LLC (WRPS) is the prime contractor for the Department of Energy (DOE) Tank Farm Operations at the Hanford Site, and is responsible for the management and retrieval of millions of gallons of radioactive and chemical wastes, stored in 177 underground tanks; a legacy of decades of production activities at the Site. The potential for workforce exposure to the chemical vapors from the tanks has long been a concern for the workforce and for DOE and its tank contractors; concerns about tank vapors is an issue that pre-dates WRPS's incumbency as the Tank Operations Contractor. In response to an increase in the number of tank vapor events reported by workers at the Hanford Site in 2014, WRPS commissioned the Savannah River National Laboratory with establishing and overseeing a panel of external, independent experts (Tank Vapor Assessment Team (TVAT)) to examine chemical vapor management and related worker-protection measures at the Hanford Tank Farms. The TVAT released the Hanford Tank Vapor Assessment Report (SRNL-RP-2014-00791) in late 2014, which included several recommendations to reduce the potential for chemical vapor exposures. From 2015- 2018, governmental and external groups conducted additional assessments to review the progress made in implementing the TVAT recommendations, and the overall Industrial Hygiene (IH) program. All of these assessments specifically recommended WRPS take action to improve communications with the workforce around the subject of tank vapors. Some further recommended assessing the effectiveness of vapors-related communications. In fiscal year 2016, WRPS and DOE Office of River Protection (DOE-ORP) formed an Integrated Project Team (IPT) to: (1) develop the strategy for addressing chemical vapors and (2) define the future chemical vapor protection actions at the Tank Farms. The actions are designed to address the recommendations from the external assessments as part of the overall effort to mitigate vapors-related exposure incidences, and to ensure workers are safe and feel safe while working in and around the Hanford Tank Farms. A comprehensive vapor management communication plan, engagement processes, and effectiveness measurements were established as essential components of the IPT effort. The Chemical Protection Program Office (CPPO) was formed, in part, to deliver on these IPT initiatives, monitor performance, and drive improvements to WRPS's vapors-related communications and engagement efforts at the Hanford Tank Farms. The CPPO was created as a temporary program office tailored to address these unique challenges by augmenting traditional company performance monitoring and communications (i.e. all employee e-mails, posters, and formal briefings). Modeled in broad concept after the successful program office WRPS created to support the American Recovery and Reinvestment Act, CPPO has also proven successful in its mission. Because concerns about chemical vapors in the workplace were expressed by the workforce, they are a key stakeholder. As such, the CPPO has concentrated its information sharing efforts toward the WRPS workforce. With a focus on empathetic engagement, continuous improvement, and transparent information sharing, the CPPO has developed and implemented a strategy for improving worker trust in vapors-related communications and increasing the workforce knowledge of responses taken to address chemical vapors. Effective implementation of this strategy is demonstrated by the results of workforce surveys, which indicate measured and important improvement in the effectiveness of vapors-communications and the knowledge level workers report about vapor issues compared to the previous year. This paper discusses the utilization of a temporary program office and the unique approach that the CPPO implemented to achieve success, including: strategic application of the technical and communications staff skill mix of the organization (including talent development opportunities such as stretch assignments for WRPS's Strategic Talent Development program members and support from WRPS college interns), teaming with other WRPS' organizations such as IH, Engineering and Communications and Public Relations (C and PR), the development of new types of information sharing to support the effort, and the methods by which the effectiveness of the communications efforts are measured to drive continuous improvement. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2018

Used Fuel Dry Storage Systems and Components for Shutdown Plants to Expedite Defueling of Spent Fuel Pool - 18378

For plants that have announced plans to shut down, their main priority is to off-load the Used Nuclear Fuel from the spent fuel pool to dry storage at an ISFSI so that they can proceed to 'Safe store' or other storage options, and start their decommissioning process as soon as possible. One of the major expenses for a decommissioned plant is the cost of maintenance of the spent fuel pool. Therefore, the ability of the dry storage system to store short cooled fuel is an important aspect of dry storage system for shutdown plants. When a shutdown plant evaluates the dry storage options, total cost of the transferring the fuel from the pool to ISFSI site needs to be evaluated. One of the major costs to the utility for dry storage is the cost of ISFSI pad (basemat) along with the cost of dry storage system hardware. Smaller ISFSI footprint saves utility for the cost of ISFSI site excavation, cost of engineered backfill and cost of ISFSI pad. In order to minimize the cost of dry storage systems, besides the size of the ISFSI pad as described above, other important considerations is to use high capacity systems. The highest capacity systems available in the dry storage market today are with 37 PWR or 89 BWR used fuel assemblies per canister. These dry storage systems are expected to be at the plant sites for extended duration due to the unavailability of Interim Storage Facilities or a permanent disposal sites like Yucca Mountain. Maintaining the integrity of the dry storage systems canisters and storage overpack so that they can safely protect the fuel and integrity of used nuclear fuel is maintained during storage period is of utmost importance. Robust Aging Management Program is an important aspect for dry storage systems not only at the shutdown plants but also at the operating plants. This paper will provide the update of a reduced footprint version of TN Americas NUHOMS{sup R} System with MATRIX HSM and NUHOMS{sup R} EOS Canisters that addresses the need for maximizing safety, ISFSI capacity while optimizing cost. It will provide an update on the current capabilities, design features and current status of the licensing and deployment of NUHOMS{sup R} EOS System. It will provide the current status of the MATRIX HSM along with the significant enhancement included for a robust Canister Evolved Safety Program for Aging Management. It will also describe the construction sequence; loading operations, and inspections during extended storage as a part of aging management program. The compact version of TN Americas NUHOMS{sup R} System with MATRIX HSM offers a 'Universal' Storage Overpack which is designed to accept all different designs dry storage canisters available in the industry. As UNF storage continues to drives the industry towards innovations that address the need for optimized dry storage systems, compact ISFSIs and prudent aging management programs, this new evolution of the TN Americas NUHOMS{sup R} system with MATRIX HSM and EOS Canisters offers a significant leap forward in addressing all of these challenges. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2023

National‐Scale Assessment of Total Gaseous Mercury Isotopes Across the United States

Abstract With the 2011 promulgation of the Mercury and Air Toxics Standards by the U.S. Environmental Protection Agency, and the successful negotiation by the United Nations Environment Program of the Minamata Convention, emissions of mercury (Hg) have declined in the United States. While the declines in atmospheric Hg concentrations in North America are encouraging, linking the declines to changing domestic and global source portfolios remains challenging. To address these research gaps, the U.S. Geological Survey initiated the first national‐scale effort to establish a baseline of total gaseous mercury stable isotope values at 31 sites distributed across the United States. Results indicated that unique Hg sources, such as Hg evasion from an elemental Hg contaminated site or free tropospheric intrusions in high altitude sites, were distinguishable from background atmospheric values. Minor gradients were observed across the nation, with regions of heavy industrial activity demonstrating lower δ 202 Hg, but no consistent changes in other isotopes such as Δ 199 Hg and Δ 200 Hg were observed. Furthermore, δ 202 Hg was impacted by foliar uptake and senescence but trends varied between forested regions in the northeastern and midwestern United States. These data demonstrate regional emission sources and other environmental variables can impact total gaseous Hg (TGM) isotope values, highlighting the need to characterize atmospheric Hg isotopes over larger geographical areas to evaluate changes related to national and international Hg regulations.

Tate, Michael T.↗

DOE OSTI2012

Quantum Capacitance in Topological Insulators

Topological insulators show unique properties resulting from massless, Dirac-like surface states that are protected by time-reversal symmetry. Theory predicts that the surface states exhibit a quantum spin Hall effect with counter-propagating electrons carrying opposite spins in the absence of an external magnetic field. However, to date, the revelation of these states through conventional transport measurements remains a significant challenge owing to the predominance of bulk carriers. Here, we report on an experimental observation of Shubnikov-de Haas oscillations in quantum capacitance measurements, which originate from topological helical states. Unlike the traditional transport approach, the quantum capacitance measurements are remarkably alleviated from bulk interference at high excitation frequencies, thus enabling a distinction between the surface and bulk. We also demonstrate easy access to the surface states at relatively high temperatures up to 60 K. Our approach may eventually facilitate an exciting exploration of exotic topological properties at room temperature.

36 MATERIALS SCIENCE↗

DOE OSTI2024

Data-driven Modeling for Grid Edge IBRs: A Digital Twin Perspective of User-Defined Models

Recent events in Odessa have brought attention to the challenges associated with the interaction between Inverter- Based Resources (IBRs) and the transmission and distribution system. The NERC event diagnosis report has highlighted sev- eral issues, emphasizing the need for continuous performance monitoring of these IBRs by system operators. Key areas of concern include the mismatch of control and protection perfor- mance of IBRs between the original equipment manufacturer (OEM)-provided models and field measurements. The inability to replicate the realistic response can result in incorrect reliability and resilience studies. In this paper, we developed an approach on how to emulate the behavior of an IBR using measurement data obtained for system operators to utilize in real-time and long- term planning. Two experiments are conducted in the phasor domain and electromagnetic transients (EMT) domain to emulate the behavior for grid forming and grid following inverters under various operating conditions and the effectiveness of the proposed model is demonstrated in terms of accuracy and ease of utilizing user-defined models (UDMs)

Mahapatra, Kaveri [BATTELLE (PACIFIC NW LAB)]↗

DOE OSTI2020

A Digital Twin Approach to Study Additive Manufacturing Processing Using Embedded Optical Fiber Sensors and Numerical Modeling

One of the major challenges for metal-powder-based additive manufacturing is measuring and mitigating residual strain induced during the manufacturing processes. This article reports distributed fiber optic sensors embedded in Inconel alloy components as experimental means to validate numerical models of additive manufacturing process. Electroplating was used to deposit a metal protective jacket onto standard telecom single-mode fibers for strain measurements, Fiber sensors were embedded in an Inconel alloy substrate using the laser engineered net shaping (LENS) process. Here by using a Rayleigh-scattering optical frequency domain reflectometer (OFDR), temperature changes, and residual strain in the metal substrate were monitored with 5 mm spatial resolution during the LENS process. Using finite element analysis, temperature and strain profiles induced by the LENS deposition processes were also numerically studied. Discrepancies between the simulated temperature and strain profiles and those measured directly were less than 10%. Results presented in this article demonstrates a digital twin approach to fuse modeling results with distributed fiber sensor measurement data to study additive manufacturing process toward design and fabrication process optimization.

36 MATERIALS SCIENCE↗