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[en] In recent years, coincidence spectroscopy of photo and Auger electrons helped to investigate the de-excitation of atoms, molecules and solids. These techniques are, for example, used at synchrotrons to analyze the emission of multiple electrons due to Auger processes that follow the excitation or ionization of inner-shell electrons. The total kinetic energy of the emitted electrons allows to obtain information about the spectrum and population of the final states, while the individual electron energies reveal details about the intermediate states, and therefore the decay pathways of an Auger cascade.
[en] This publication documents the results achieved by participants of an IAEA coordinated research project (CRP) related to hydrogen production using nuclear energy. The IAEA has previously developed the Hydrogen Economic Evaluation Programme (HEEP) that supports the analysis of various options for future hydrogen economies. HEEP is the first of its kind software and has been distributed freely to IAEA Member States. The CRP participants performed a generic benchmark analysis for various scenarios of hydrogen production and against other codes built on different platforms and models. The research report highlights various aspects of nuclear hydrogen production based not only on national but also international trends. It considers important technical aspects of coupling nuclear reactors to hydrogen plants and the challenges for nuclear hydrogen production compared to steam or solar energy produced hydrogen. Major accomplishments achieved by Member States are presented in the summary section of this report. A detailed description of the activities and outcomes through the implementation of the CRP can be found in the individual country reports available on the CD-ROM attached to this publication.
[en] Since 2014, the installed solar capacity in South Carolina (SC) has mushroomed from 5.5 megawatts to more than 354 megawatts today. Concurrently, the number of customer-sited, load-centered solar generation was expected to grow from less than 600 statewide to as many over 10,000 today. This growth was the direct result of a landmark state policy initiative, Act 236, passed by the SC General Assembly and signed into law by the Governor in June of 2014. Local policy makers in SC were ill-equipped to handle the onslaught of solar permitting and zoning requests expected by 2021. Similarly, the state’s building inspectors, first responders, and tax assessors know little about photovoltaic (PV) technology and best practices. Finally, SC’s workforce and workforce trainers were underprepared to benefit from the tremendous opportunity created by the passage of Act 236. Each of these deficits in knowledge of and preparedness for solar PV translated into higher “soft costs” of installed solar PV in SC. The Savannah River National Laboratory (SRNL), together with almost a dozen electricity stakeholders in the Southeast, has studied the ability of Act 236 to serve as replicable model for solar PV cost reduction. In 2015, this study began with a focus on the effects of Act 236 to offer a unique perspective and understanding of the actual impact of rapidly integrating solar energy into the electric grid. This study would analyze the impact of starting at a solar PV penetration of 0.1% and increasing to over 2%, while expanding access, developing regional specific training and educational materials, and developing datasets to support expanding solar markets. Through targeted tracking and analysis, the team developed a baseline of the current market, identified the major obstacles in soft cost reduction, and cooperatively developed stakeholder-centric strategies. This work has enabled us to directly track and report on the growth and effects of recently enacted solar legislation on the industry. This report marks the final in a series of reports examining the effects of Act 236 on the solar economy in SC since 2014.
[en] From 2016-2021, the installed solar capacity in South Carolina will mushroom from less than 20 megawatts to more than 300 megawatts. Concurrently, the number of customer-sited, load-centered solar generation is expected to grow from less than 500 statewide to as many as 10,000 by 2021. This growth is anticipated to be the direct result of a landmark state policy initiative, Act 236, passed by the South Carolina General Assembly and signed into law by the Governor in June of 2014. Local policy makers in South Carolina are ill-equipped to handle the onslaught of solar permitting and zoning requests expected over the next five years. Similarly, the state’s building inspectors, first responders, and tax assessors know little about photovoltaic (PV) technology and best practices. Finally, South Carolina’s workforce and workforce trainers are underprepared to benefit from the tremendous opportunity created by the passage of Act 236. Each of these deficits in knowledge of and preparedness for solar PV translates into higher “soft costs” of installed solar PV in South Carolina. Currently, we estimate that the installed costs of residential rooftop solar are as much as 25 percent higher than the national average. The Savannah River National Laboratory (SRNL), together with almost a dozen electricity stakeholders in the Southeast, proposes to create a replicable model for solar PV soft cost reduction in South Carolina through human capacity-building at the local level and direct efforts to harmonize policy at the inter-county or regional level. The primary goal of this effort is to close the gap between South Carolina installed costs of residential rooftop solar and national averages. The secondary goal is to develop a portable and replicable model that can be applied to other jurisdictions in the Southeastern US.
[en] The United States Department of Energy, Office of Nuclear Energy, Fuel Cycle Technology Program sponsors nuclear fuel cycle research and development. As part of its Fuel Cycle Options campaign, the DOE has established the Nuclear Fuel Cycle Options Catalog. The catalog is intended for use by the Fuel Cycle Technologies Program in planning its research and development activities and disseminating information regarding nuclear energy to interested parties. The purpose of this report is to document the improvements and additions that have been made to the Nuclear Fuel Cycle Options Catalog in the 2016 fiscal year.
[en] Excellent technology of government-funded research institute is not spin-on into the national defense field because many researchers in the institute do not accurately recognize the system and characteristics of national defense R&D. As a result, the basic source technology capability of national defense R&D is lacking. In addition, despite the lack of basic source technologies, the national defense field is focusing on weapon systems-oriented R&D, which is the main reason of the slow development of national defense science and technology capacity. Therefore, in this report, the intention of science and technology of national defense R&D is examined by analyzing the state of national defense R&D investment based on the national economic scale and national R&D investment and predicting future. The national defense R&D environment is understood by analyzing the strengths and weaknesses of national defense R&D projects, civil-military technology cooperation projects, and future national defense R&D projects and examining cooperation relationships between national defense agencies and private institutions. The technology of our research institute related to national defense R&D policy direction is discovered, and integrated national defense R&D convergence plan is proposed with considering national defense R&D characteristics. An efficient and systematic national defense R&D participation condition is created for our researchers. Moreover, the characteristics, pros and cons, and differences related to national defense R&D are introduced to make efficient judgments through institutional understanding for convergence of out institute technology and national defense R&D. In conclusion, an efficient national defense R&D convergence method of atomic energy technology is proposed by effectively integrating our research capacity into national defense R&D in accordance with the government policy that emphasizes the strengthening of future national defense capacity and by contributing to the acquisition of state-of-the-art weapon systems resulting of expanding the capabilities of basic source national defense R&D. When this is institutionalized, an environment that will encourage researchers to participate in national defense R&D will be fostered
[en] Sustainability of nuclear power plants is accomplished through integrity and reliability of nuclear systems/structures/components. Verification of reliability for secondary side piping and reactor internal structural component is essential to integrity improvement and advancement in technology of nuclear power plant. Test facilities for flow accelerated corrosion of secondary side pipe and irradiation assisted stress corrosion cracking of reactor internal structural component will be constructed and verified data will be produced using the facilities. Nuclear power plant design technology is a world class competitiveness, but domestic materials properties database that are used as a design data of nuclear power plant are very scarce. Therefore, It is intended to establish a foundation for the certification of international nuclear material specifications and infrastructure for a unique standardization of nuclear material of Korea type based on already secured the national reference standard quality assurance system and measurement/evaluation/verification systems for the nuclear structural materials physics properties and high reliable material information DB construction. Digitization of instrumentation and control system in nuclear power plant persists as to check the system safety, It is required to construct scheme that evaluate safety compliance of system software and human factors engineering. It should be developed simulator-based, realistic simulation facilities-based, and software/human factors integrated system for this purpose. The application of computer and network technologies in nuclear power plants evokes research needs for cyber incident response. ESF-CCS among the safety systems, DPS among the non-safety systems, and IPS are selected as test-beds, which are important to researches on the response to nuclear cyber security threats. Then these test-beds are designed, fabricated and tested, based on our experience on the design and development of Korean nuclear digital I&C systems. Along with the test-beds, monitoring technologies are developed for the close examination of behavior changes in digital I&C systems induced by cyber attacks. Online monitoring and diagnostic of nuclear pressure vessels and machinery and developments of monitoring systems was carried out. Health monitoring methods and novel sensors using vibration and ultrasonic signals for pipes and pressure vessels and machinery such as main water feed pumps was studied. World-class NIMS and a diagnostic platform were developed for the practical use of research results. To enhance public safety and minimize economic loss caused by nuclear accident, unmanned mobile monitoring and response system should be established for early response and mitigating nuclear accident. Remote monitoring technology such as radioactive detection and hydrogen detection lidar should be developed. And aerial and ground mobile platform for accessing hazardous area should be developed
[en] Full text: Hot-spot ignition planned at the National Ignition Facility (NIF) requires proper assembly of the DT fuel, as manifested by the evolution of areal density (ρR) symmetry and hotspot ion temperature (Ti). Ideally, a spherically symmetric layer of cold dense fuel with ρR > 1 g/cm2 surrounding a∼5 keV lower-density hot spot is obtained at peak convergence. To reach these conditions, the implosion must be 1D in nature and efficient conversion of implosion kinetic energy to hot-spot thermal energy must be obtained. If substantial 3D nonuniformities in the implosion exist, conversion efficiency is degraded and a significant fraction of implosion kinetic energy, in bulk-fluid motion form, remains at peak convergence. Experimentally, residual bulk-fluid motion is assessed from directional measurements of the primary DT and DD neutron spectrum. The width of the primary spectrum is characteristic of Ti as well as the variance of the bulk-fluid motion in the burning region. Energy shifts beyond Ti-induced shifts are also an indication of bulk-fluid motion. As well, ρR asymmetries are determined from directional yield measurements of scattered or unscattered neutrons. In recent high-foot-implosion experiments, directional measurements of the neutron spectrum illustrate the existence of substantial bulk-fluid motion and low-mode ρR asymmetries at peak convergence, which degrade the implosion performance. The measured DT-weighed apparent Ti is also consistently higher than the apparent DD-weighed Ti, a discrepancy that increases with increasing implosion drive. From a 1D perspective, the DD yields are also too high relative to DT yields. Effects due to profiles, reactivity differences, and bulk-fluid motion partly explain these observations, but none of them appear sufficient to explain the data. The observables are most likely caused by significant ρR asymmetries (> 500 mg/cm2) and substantial bulk-fluid motion of about 50–100 km/s. The hypothesis is that these observations are driven by radiation drive asymmetry, and instabilities seeded by the fill tube and thin tent holding the capsule in the hohlraum. These issues are currently being addressed by new engineering solutions, more refined implosion modelling, and implementation of new diagnostics. (author)
[en] AFC management and integration activities in FY-17 included continued support for international collaborations, primarily with France, Japan, the European Union, Republic of Korea, and China, as well as various working group and expert group activities in the Organization for Economic Cooperation and Development Nuclear Energy Agency (OECD-NEA) and the International Atomic Energy Agency (IAEA). Three industry-led Funding Opportunity Announcements (FOAs) and two university-led Integrated Research Projects (IRPs) funded in 2013, made significant progress in fuels and materials development. All are closely integrated with AFC and accident-tolerant fuels (ATF) research. Accomplishments made during FY-17 are highlighted in this report, which focuses on completed work and results.