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At least 19 records

Advanced Reactor Control and Operations (ARCO): A University Research Facility for Developing Optimized Digital Control Rooms

The Advanced Reactor Control and Operations (ARCO) facility was constructed in January 2018 to serve as a test bed for advanced reactor control rooms and operator support systems. Since then, it has supported human-machine interface user experience research, fault detection and mitigation technology development, control room concept of operations development, and remote operations research. ARCO serves as the control room for the Compact Integral Effects Test (CIET) facility, which replicates the primary-side flow paths and thermal-hydraulic behavior of a fluoride-salt-cooled high-temperature reactor (FHR) using simulant fluids and scaling principles. New reactor designs feature different operating conditions and scenarios than those in existing reactors. ARCO supports the research and development of digital tools for operator communications, intuitive real-time data analysis, online health monitoring and prognostics, and control room cybersecurity. By integrating these different technologies, ARCO acts as a prototypical control system to iteratively develop methods and tools of operation in advanced small modular nuclear reactors. This paper describes the features of and challenges to operating advanced small modular reactors underlying the design basis for ARCO and its operator support systems.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

arco (Assembled Resource-Constrained Optimization) [SWR-26-030]

Arco (Assembled Resource-Constrained Optimization) is a memory-smart optimization DSL and solver for LP and MIP problems on constrained hardware. The software is an optimization framework built around a KDL-based domain-specific language and a CLI compiler/solver. You write optimization models in .kdl files, and the arco CLI compiles, validates, inspects, and solves them. Language bindings (Python today, more planned) provide programmatic access to the same engine. Built for harder optimization problems on constrained resources, Arco is intentional about every allocation, careful with stack and heap behavior, and relentless about minimizing memory usage so more systems can run real workloads. Arco is built primarily for internal use within our organization. You are welcome to try it, but we make no guarantees about API stability or robustness at this stage

Sanchez Perez, Pedro Andres [National Laboratory o↗

Historic American Landscapes Survey: Arco Naval Proving Ground (Idaho National Laboratory)

Based on historical evaluations in 1993 and 1997, historians determined that the then-remaining Arco NPG structures were significant to the nation’s history through their association with World War II . Through ensuing discussions with the SHPO, it was further determined that the infrastructure and associated landscape were also significant. According to provisions of INL’s Cultural Resource Management Plan (CRMP) as legitimized through a 2004 Programmatic Agreement between DOE-ID, the Idaho State Historic Preservation Office (SHPO), and Advisory Council on Historic Preservation (ACHP) historians identified the World War II structures as DOE “Signature Properties”. As defined by DOE-HQ, Signature Properties “denote its [DOE’s] most historically important properties across the complex…and/or those properties that are viewed as having tourism potential.” The INL is a secure site and the INL land and structures are not accessible to the public and, therefore have no “tourism potential”. Although DOE-ID actively sought other uses for the vacant, unused buildings, none were identified and the buildings present safety and health concerns. A condition assessment found lead based paint, asbestos, rodent infestation/droppings, small animal carcasses, mold, and, in CF-633, areas of radiological contamination. In early 2013, DOE-ID notified the Idaho SHPO, ACHP, and, as required by the INL CRMP and PA, DOE-Headquarters Federal Preservation Officer, of their intent to demolish the vacant buildings (CF-606, CF-607, CF-613, CF-632, and CF-633). The proposed “end-state” of the buildings will be either grass and/or gravel pads. Through the NHPA Section 106 consultation process, measures to mitigate the adverse impacts of demolition were determined and agreed to through a Memorandum of Agreement (MOA) between DOE-ID, SHPO, and ACHP. The measures include the development and installation of interpretive signs to be placed at a publicly accessible location, retention of original components of CF-633, and completion of this HALS standard format report. Buildings, infrastructure, and features that are not scheduled for removal are documented here as well as properties that are scheduled for removal and the overall Arco NPG landscape. The Arco NPG, located in the remote high-desert of eastern Idaho aided in the defense and eventual ally victory in the Pacific Theater of World War II, in addition to revising national standards for the safe storage and transport of conventional ordnance.

99 GENERAL AND MISCELLANEOUS↗

Comparative Study of 28 and 18 Years Field Aged Siemens-Arco M55 Modules in Temperate and Hot-Dry Climates

The primary objective of this research work is two-fold: (i) determine the degradation rates of Siemens-Arco M55 modules exposed over 18 and 28 years in a hot-dry climate of Arizona and a temperate climate of California, and; (ii) identify the potential modes responsible for these degradation losses. The degradation rates were determined based on the I-V data obtained on exposed modules and on the corresponding control modules which were not exposed in the fields. The degradation modes responsible for these degradations were determined using several nondestructive tests and destructive tests performed on these control and exposed modules. The nondestructive tests included: current-voltage, visual inspection, cell-module quantum efficiency, and module level reflectance spectroscopy. The destructive tests included: transmittance spectroscopy of glass superstrates, and FTIR, DSC and TGA of encapsulant materials.

14 SOLAR ENERGY↗

Evolution of integrated panel structural design and interfaces for PV power plants

The evolution of integrated photovoltaic (PV) panel design at ARCO Solar is discussed. Historically, framed PV modules of about 1 x 4-ft size were individually mounted in the field on fixed support structures and interconnected electrically with cables to build higher-power arrays. When ARCO Solar saw the opportunity in 1982 to marry its PV modules with state-of-the-art heliostat trackers developed by ARCO Power Systems, it became obvious that mounting individual modules was impractical. For this project, the framed modules were factory-assembled into panels and interconnected with cables before being mounted on the trackers. Since then, ARCO Solar made considerable progress and gained substantial experience in the design and fabrication of large PV panels. Constraints and criteria considered in these design activities included static and dynamic loads; assembly and transportation equipment and logistics, structural and electrical interfaces, and safety and grounding concerns.

Arnett, J. C.↗

Solar Electricity

ARCO Solar manufactures PV Systems tailored to a broad variety of applications. PV arrays are routinely used at remote communications installations to operate large microwave repeaters, TV and radio repeaters rural telephone, and small telemetry systems that monitor environmental conditions. Also used to power agricultural water pumping systems, to provide electricity for isolated villages and medical clinics, for corrosion protection for pipelines and bridges, to power railroad signals, air/sea navigational aids, and for many types of military systems. ARCO is now moving into large scale generation for utilities.

Source record↗

Managing complexity in simulations of land surface and near-surface processes

Increasing computing power and the growing role of simulation in Earth systems science have led to an increase in the number and complexity of processes in modern simulators. We present a multiphysics framework that specifies interfaces for coupled processes and automates weak and strong coupling strategies to manage this complexity. Process management is enabled by viewing the system of equations as a tree, where individual equations are associated with leaf nodes and coupling strategies with internal nodes. A dynamically generated dependency graph connects a variable to its dependencies, streamlining and automating model evaluation, easing model development, and ensuring models are modular and flexible. Additionally, the dependency graph is used to ensure that data requirements are consistent between all processes in a given simulation. Here we discuss the design and implementation of these concepts within the Arcos framework, and demonstrate their use for verification testing and hypothesis evaluation in numerical experiments.

54 ENVIRONMENTAL SCIENCES↗

Hydrocarbon production reduces natural methane seeps in the Santa Barbara channel

Abundant natural hydrocarbon seepage in the Santa Barbara Channel includes large amounts of gas, mainly methane. Numerous seeps are focused along a faulted anticlinal axis where in 1982 ARCO placed two large (900 m 2 each) steel gas capture tents on the seabed adjacent to Platform Holly. The seep rate into the tent at high tide is about 5 percent less compared with low tide (2m tidal range). An earthquake in 2013 (M = 4.8) did not affect seepage rates into the steel tents, indicating that gas was not released by fault dilation. The CO 2 and H 2 S content of the captured gas are anomalously low compared to typical Holly gas due to bacterial and sea water-gas interaction at the seep tent. Platform Holly production had an overall effect of reducing gas seepage into the tents over time. Wells beneath the tents at 1-km depth had a much greater influence on the seepage rate than more distal wells. The nearby wells had a direct effect on seepage rate when they were put on production (seepage decreased) versus shut in (seepage increased). The response time was within hours, indicating a direct hydraulic connection between the reservoir at 1 km subsea and the seabed. Permeability of the approximate 1-km fault pathway between the reservoir and the seep tent is calculated to be about 3 × 10 -14 m 2 (30 millidarcys). Gradually, the seep rate declined from peak flow in 1990 (4.5×10 4 m 3 dy-1) to less than 7.1×10 3 m 3 dy -1 in 2013. In June of 2013, a horizontal well was completed high on the structural anticline between Platform Holly and directly beneath the seep tents. Within three weeks of turning on this new well, seepage into the tents completely ceased, ending more than 30 years of natural methane seepage captured by the tents.

58 GEOSCIENCES↗

Investigation of Coupled Processes and Impact of High Temperature Limits in Argillite Rock

Shale and clay-rich geological formations have been considered as potential host rock for geological disposal of high-level radioactive waste throughout the world, because of their low permeability, low diffusion coefficient, high retention capacity for radionuclides, and capability to self-seal fractures. Permeabilities arising from the primary porosity of these rock types are low because of the extremely fine-grained constituents and the very small pores associated with the fine-grained material. Permeability values are typically less than 10 microdarcies (10-17 m2 or about 10-10 m/s equivalent hydraulic conductivity) and are often two to four orders of magnitude lower. While fractures can occur, clay and shale often demonstrate the tendency to self-seal fractures, which reduces the effects of fractures on bulk permeability. This occurs as a result of swelling from the increased water potential in fractures, the generation of fracture infilling materials and mineral precipitation, and plastic deformation of the rock (Mazurek et al., 2003). The low permeability of clay and shale rock are well-known in the hydrogeology community where these rock types represent aquitards that severely limit groundwater movement, and in petroleum geology, where they act as caprocks limiting the rise of buoyant petroleum fluids. Other favorable characteristics of clay/shale rock are the strong sorptive behavior for many radionuclides and (in saturated systems) the low flow rates, which typically lead to reducing conditions because of the lack of oxygen transport from the surface. Clay and shale rock also act to chemically buffer the effects of materials introduced through repository construction, operation, and emplaced materials (Arcos et al., 2008).

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Energy Technology Proving Ground Program Plan

New methods of energy production and distribution are required to meet clean energy goals and demands across all U.S. energy sectors. Idaho National Laboratory’s (INL) Integrated Energy Systems (IES) initiative is enabling clean energy research, development, and demonstration (RD&D) activities. To date, IES demonstration programs have been limited by distributed infrastructure and a lack of large-scale facilities to accommodate industry-scale research of Technical Readiness Level (TRL) 6-8 technologies. The IES initiative plans to eliminate these constraints by establishing a new research complex at INL known as the Energy Technology Proving Ground (Proving Ground) to be led by the Energy and Environment Science and Technology Directorate. The Energy and Environment Science and Technology (EES&T) directorate, one of five Idaho National Laboratory (INL) RD&D organizations, focuses on clean energy technologies that anchor the industry-enabling research of the Proving Ground. The Proving Ground will combine diverse clean energy systems into lean integrated test bed of independent multiscale capabilities available to the government and commercial industries to perform research; and will enable INL’s goal of becoming a Net-Zero entity by 2031. This program encompasses existing and new research space at both the in-town Research and Education Campus (REC) and the Arco desert site (the Site). The Proving Ground will support the maturation of IES technologies from TRL 1 through 8 by providing the infrastructure and capabilities needed to sustain a continuum of RD&D from basic science to industry-scale. To establish The Proving Ground and meet INL’s net-zero goals by 2031, nine research program areas have been identified within the IES initiative that require expanded and new capital infrastructure. This program plan provides guidance for establishing the Proving Ground at the Site for plug-and-play pilot testing and proofing of integrated energy system functionality including fission and renewable energy sources for industry driven application platforms.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Energy Technology Proving Ground FY-2026 Program Plan (Rev.1)

New methods of energy production and distribution are required to meet clean energy goals and demands across all U.S. energy sectors. Idaho National Laboratory’s (INL) Integrated Energy Systems (IES) initiative is enabling clean energy research, development, and demonstration (RD&D) activities. To date, IES demonstration programs have been limited by distributed infrastructure and a lack of large-scale facilities to accommodate industry-scale research of Technical Readiness Level (TRL) 6-8 technologies. The IES initiative plans to eliminate these constraints by establishing a new research complex at INL known as the Energy Technology Proving Ground (Proving Ground) to be led by the Energy and Environment Science and Technology Directorate. The Energy and Environment Science and Technology (EES&T) directorate, one of five Idaho National Laboratory (INL) RD&D organizations, focuses on clean energy technologies that anchor the industry-enabling research of the Proving Ground. The Proving Ground will combine diverse clean energy systems into lean integrated test bed of independent multiscale capabilities available to the government and commercial industries to perform research; and will enable INL’s goal of becoming a Net-Zero entity by 2031. This program encompasses existing and new research space at both the in-town Research and Education Campus (REC) and the Arco desert site (the Site). The Proving Ground will support the maturation of IES technologies from TRL 1 through 8 by providing the infrastructure and capabilities needed to sustain a continuum of RD&D from basic science to industry-scale. To establish The Proving Ground and meet INL’s net-zero goals by 2031, nine research program areas have been identified within the IES initiative that require expanded and new capital infrastructure. This program plan provides guidance for establishing the Proving Ground at the Site for plug-and-play pilot testing and proofing of integrated energy system functionality including fission and renewable energy sources for industry driven application platforms.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Dryocosmus kuriphilus Yasumatsu (Hymenoptera: Cynipidae) in Minho (Northern Portugal): Bioecology, Native Parasitoid Communities and Biological Control with Torymus sinensis Kamijo (Hymenoptera: Torymidae)

The Asian chestnut gall wasp Dryocosmus kuriphilus Yasumatsu, native to China, was first detected in Europe in Italy in 2002. In Portugal it was declared in 2014, and it has since affected the Portuguese chestnut production. The introduction of its natural parasitoid Torymus sinensis Kamijo started through inoculative releases according to the National Action Plan for the Control of Dryocosmus kuriphilus, established by the Direção Geral de Alimentação e Veterinária (DGAV), in 2015. This research was carried out during 2018 and 2019, in five chestnut orchards in the Minho region (Northern Portugal). Between January and March 2018, at each location, three monthly harvests of 100 buds were carried out to determine the infestation level. Between April and June 2018, 240 galls were harvested every two weeks, with the purpose of studying the bioecology of D. kuriphilus. In each sampling site, 160 galls were placed in emergence boxes to follow adults of the D. kuriphilus population, and 80 galls were dissected with a binocular magnifying glass, to count and record the evolution of the larval stages of D. kuriphilus and of the parasitoids. The identification of T. sinensis and native parasitoids was carried out. The parasitism rates and Simpson diversity indices were determined. The percentage of buds infested by D. kuriphilus was high in all studied places, varying between 67% and 80%, regardless of the number of T. sinensis releases made and of the chestnut cultivars present in each orchard. The highest rate of parasitism by T. sinensis was 0.5044% and it was recorded in an orchard where there were two releases of T. sinensis in 2016 and 2017 (Arcos de Valdevez—Rio Cabrão—P1). Considering that the exotic parasitoid has already been released in the region since 2016, its establishment in all the chestnut orchards studied was confirmed, although with very low parasitism rates. The natural parasitism associated with the native parasitoid species of D. kuriphilus was confirmed in this work, recording values between 34% and 51% of the parasitized chestnut galls, with 11 species of native parasitoids having been identified: Eupelmus azureos, Eupelmus uruzonus, Eurytoma brunnivientris, Eurytoma pistaciae, Megastigmus dorsalis, Mesopolobus sp., Ormyrus pomaceus, Sycophila biguttata, Sycophila iracemae, Sycophila variegatta and Torymus flavipes.

Amorim, Amaro↗

Qualification testing and electrical measurement experience: A manufacturer's view

ARCO Solar's experiences as a participant in an industry-utility-government environmental qualification team examining photovoltaic devices are discussed. Included is an assessment of the applicability, completeness and appropriateness of the testing procedures and of the acceptance criteria for megawatt-sized procurements for utilities. Like the stand-alone users, the utility industry is interested in obtaining low costs, but additional concerns exist related to reliability and durability, safety, grounding and overall system criteria including performance prediction (related to output power acceptance testing), power quality and dispatchability. For purposes of this first major purchase of photovoltaic modules and panels by the utility industry, there was a carry-over of the JPL specifications. The need exists for futher development, assessement, and selection of qualification and testing standards and evaluation criteria specifically addressing these additional concerns for utility-connected PV power-plant applications.

Arnett, J. C.↗

Qualification testing for a central station

Qualification testing for a Central Station Photovoltaic (PV) Facility depends to a great extent on the system design, (fixed versus tracking), and the level of data acquisition/control which is incorporated into the system. The basic elements which require qualification tests include: dc power production/collection; tracker conversion systems; ac utility interface; system level control; and data acquisition/reporting. The qualification tests from the Lungo (ARCO) 1 MW Facility which were completed in January 1983 are discussed. The philosophy and many of the procedures are applicable to any central station PV facility.

Forrester, D. L.↗

Light-induced effects-impacts to module performance measurements and reliability testing: An overview

The stability of solar cells is a key factor in determining the reliability of photovoltaic modules and is of great interest in the case of solar cells having a new technology which has not yet been fully developed. In particular this question arises with hydrogenated amorphous silicon (a-Si) solar cells because a-Si exhibits reversible light induced changes in its electronic properties, commonly referred to as the Staebler-Wronski effect (SWE). Continuous progress is being made in the peak conversion efficiencies of a-Si solar cells and efficiencies in excess of 11% have been achieved. However, stability is still a problem. ARCO Solar reports results on solar cells which, after over a year's exposure to sunlight, under open circuit conditions, still have about 7% conversion efficiency. Other results show a region of fast degradation for about a month, after which the degradation diminishes rapidly.

Wronski, C. R.↗

Thin film module development

The design of ARCO Solar, Inc.'s Genesis G100 photovoltaic module was driven by several criteria, including environmental stability (both electrical and mechanical), consumer aesthetics, low materials costs, and manufacturing ease. The module circuitry is designed as a 12 volt battery charger, using monolithic patterning techniques on a glass superstrate. This patterning and interconnect method proves amenable to high volume, low cost production throughput, and the use of glass serves the dual role of handling ease and availability. The mechanical design of the module centers on environmental stability. Packaging of the glass superstrate circuit must provide good resistance to thermal and humidity exposure along with hi-pot insulation and hailstone impact resistance. The options considered are given. Ethylene vinyl acetate (EVA) is chosen as the pottant material for its excellent weatherability.

Jester, T.↗

Reliability and engineering sciences area. Materials research: Single junction thin film

A test bench was designed and fabricated for the purpose of improving control of hot-spot test accuracy. Electrochemical corrosion research focused on corrosion mechanisms to which both crystalline and a-Si modules may be subjected in central station applications. A variety of cells and several designs were subjected to accelerated stress tests. Humiditiy degradation rates were determined and key electrochemical failure mechanisms were identified. Software was developed for the prediction of power loss resulting from open circuits in an array field of a-Si modules. Failure analysis was continued on the four ARCO Solar Genesis modules. The interactions of water on the silicon module was examined. An autocatalytic photooxidation model was proposed. The reliability and durability of bonding materials and electrical insulation were also studied.

Source record↗