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At least 1,243 records · Page 69

Status Report on the High-Temperature Steam Electrolysis Plant Model Developed in the Modelica Framework (FY17)

This report has been prepared as part of an effort to design and build a modeling and simulation (M&S) framework to assess the economic viability of a nuclear-renewable hybrid energy system (N-R HES). In order to facilitate dynamic M&S of such an integrated system, research groups in multiple national laboratories have been developing various subsystems as dynamic physics-based components using the Modelica programming language. In fiscal year 2015 (FY15), Idaho National Laboratory (INL) performed a dynamic analysis of two region-specific N-R HES configurations, including the gas-to-liquid (natural gas to Fischer-Tropsch synthetic fuel) and brackish water reverse osmosis desalination plants as industrial processes. In FY16, INL developed two additional subsystems in the Modelica framework: (1) a high-temperature steam electrolysis (HTSE) plant as a high priority industrial plant to be integrated with a light water reactor (LWR) within an N-R HES and (2) a gas turbine power plant as a secondary energy supply. In FY17, five new components (i.e., a feedwater pump, a multi-stage compression system, a sweep-gas turbine, flow control valves, and pressure control valves) have been incorporated into the HTSE system proposed in FY16, aiming to better realistically characterize all key components of concern. Special attention has been given to the controller settings based on process models (i.e., direct synthesis method), aiming to improve process dynamics and controllability. A dynamic performance analysis of the improved LWR/HTSE integration case was carried out to evaluate the technical feasibility (load-following capability) and safety of such a system operating under highly variable conditions requiring flexible output. The analysis (evaluated in terms of the step response) clearly shows that the FY17 model resulted in superior output responses with much smaller settling times and less oscillatory behavior in response to disturbances in the electric load than those observed with the FY16 model. Simulation results involving several case studies show that the suggested control scheme could maintain the controlled variables (including the steam utilization factor, cathode stream inlet composition, and temperatures and pressures of the process streams at various locations) within desired limits under various plant operating conditions. The results also indicate that the proposed HTSE plant could provide operational flexibility to participate in energy management at the utility scale by dynamically optimizing the use of excess plant capacity within an N-R HES.

08 HYDROGEN↗

Chemical Looping Coal Gasification Sub-Pilot Unit Demonstration and Economic Assessment for IGCC applications (Final Report)

The Ohio State University (OSU) coal to syngas (CTS) technology is an advanced air separation process that can be applied for electricity production via an integrated gasification combined cycle (IGCC). The objective of the proposed project is to enable the OSU CLG technology for a commercially relevant demonstration by 2020. In order to accomplish this objective, small pilot scale demonstration of the CLG reactor system was performed. The small pilot test unit incorporates commercially scalable non-mechanical gas sealing and solids flow control components for extended operations of the integrated reactor system. A cumulative demonstration of greater than 100 hours was performed to confirm the reliability of the reactors (reducer and oxidizer) and non-mechanical devices in maintaining controlled solid circulation, gas sealing, and coal distribution in the reactor (reducer) as well as to confirm sustained syngas product performance. A comprehensive techno-economic analysis (TEA) of the OSU CLG process for IGCC application was conducted with the support of WorleyParsons, Ltd. (WP) and compared to the Department of Energy (DOE) baseline IGCC report. Using the data gained from the small pilot demonstration, a complete comprehensive techno-economic analysis (TEA) of the CLG process was conducted. The evaluation was used as basis to attract utilities and coal industries in Ohio. The project duration lasts 30 months (6 months of no cost extension). Ohio coal was used in the integrated CLG small pilot unit to convert to high hydrogen syngas. A demonstration of the integrated chemical looping reactor system at the 15 kW th scale accelerates technology commercialization in the near term. The 15 kWth demonstration addressed several major technology gaps, such as coal injection and distribution in the reducer, controllable solids circulation with the desired fuel to solids ratio, system pressure distribution for proper gas sealing, effects of contaminants and fuel/oxygen carrier residence time requirements. The fates of impurities, such as SO x and NO x was also investigated in unit demonstrations. WP conducted a comprehensive system TEA to optimize the OSU CLG process design for efficient electricity generation with greater than 90% CO 2 capture in IGCC applications. The conclusion of this project supports the further scale-up of the technology to a commercially applicable large pilot scale test unit for operation by 2020. More importantly, it benefits Ohio as it provides an economically competitive mean for power generation with carbon capture. Given the rise of natural gas usage and strict environmental regulations, the use of Ohio coal is expected to decrease and thus impact the coal economy in Ohio. The conclusion of this project provided way for Ohio coal to compete in the future and secure jobs in the energy sector.

01 COAL, LIGNITE, AND PEAT↗

Transforming the Uranium Fuel Cycle: Safe & Economical Conversion of DUF 6 to DUF 4 [Slides]

Project Outcomes: Designed and fabricated SS reaction vessels for executing reactions with UF 6 at SIGMA, followed by transport and analysis at TA-48; Established a new capability at SIGMA for performing small mass transfers of UF 6 ; Safety documentation approved for performing new UF 6 chemistry at SIGMA; Staff training and conversion opportunity established for LANL Seaborg post-doc; Neat reaction with HMDS (CH 3 ) 3 Si-Si(CH 3 ) 3 produced fluorosilanes; In reactions with solvents, fluorination observed. No DUF 4 observed yet. Observations: Only 4 reactions were completed – more clearly needed; Due to problems with procurement, we did not get the mass control flow (MFC) unit until late August; Due to staff and time shortages UF 4 was never delivered from SIGMA to TA-48 by SHIP-IT; Established ability for future collaboration between C and Sigma.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Detecting Data-Races in High-Performance Computing

High-performance computing is susceptible to data-race bugs. Data races occur when sequences of computed events do not happen in the intended order, a significant barrier to the integrity of parallel programs using shared-memory architectures. Many approaches to data-race detection are based on traditional static-analysis techniques that typically execute on a program’s source code or control-flow graph (the graphical representation of all possible orders of events in the execution of a program). Similar to classical data-flow analyses, such tools can produce false alarms that report spurious race conditions on error free programs. We have developed a software verification technique that requires as input only a program’s source code and can automatically detect a data-race bug which definitely exists, determine that a program is definitely data-race free, or report that it cannot determine either of the two cases.

97 MATHEMATICS AND COMPUTING↗

Demand Response Optimization and Management System for Real-TIme (DROMS-RT)

To design and demonstrate DROMS-RT, a highly distributed Demand Response Optimization and Management System for Real-Time (DROMS-RT) power flow control to support large scale integration of distributed renewable generation into the grid. AutoGrid developed a novel control and communications platform to allow highly dispatchable demand response (DR) services in time frames suitable for providing ancillary services to the transmission grid. These services will be substantially less expensive and more efficient than other forms of ancillary services options currently available to manage the intermittency associated with large-scale renewable integration. DROMSRT successfully leveraged Automated Demand Response (ADR) by fundamentally re-thinking the architecture of the DR platform from the ground up and by developing innovative new technologies in a number of areas related to DR. DROMS-RT leveraged the low-cost, open, interoperable DR signaling technology, OpenADR, and low-cost, internet-protocol based telemetry solutions to reduce the cost of hardware. This allowed DROMS-RT to provide dynamic price signals to millions of OpenADR clients. Statistically rigorous signal processing techniques were developed to reliably detect even small load reductions in the presence of noisy baseline profiles. Novel forecasting engines based on modern online machine learning algorithms enabled accurate individualized forecasts for customer loads in the presence of dynamic pricing signals, and a real-time decision engines enabled continuous optimization and optimal dispatch of DR resources across a large portfolio of heterogeneous loads that respond at varying time-scales. Moreover, the real-time optimization conducted by the decision engine can utilize grid physics to maximize load reduction at the transmission system in addition to the distribution sites, for more efficient grid operation. Finally, the Software-as-a-Service (SaaS) availability of the DROMS-RT platform has reduced the cost of deployment and enable participation of small commercial and residential customers in DR who otherwise would not be able to do so.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Thermal Transport Gen3 Liquid-Pathway Funds Re-Allocation Proposal

Further development of the Gen3 Liquid-Pathway project is necessary to address technical engineering challenges with respect to incorporation of a flow control valve and sodium system for the 2.0 MWth Pilot-Scale system. For the Thermal Transport development task 1.3, Sandia National Laboratories (SNL) originally set aside $\$$388,425 for the development of a heat trace test bed, however while the team felt that this work is necessary to de-risk a number critical design-related issues the team also has identified items that require more near-term attention. These items largely pertain to the Chloride molten salt values development, with operation up to 720°C, as well as operational mode/system design development as it pertains to the sodium system design, which is currently not included as part of the system design work. The Gen 3 project team requests the ~$\$$388k of funds be used to address these issues, where the previous work requested may be addressed with the 300kWth chloride molten salt loop. These funds would only be spent during the remainder of the Phase 1 budget period, in preparation of final design work for the Phase 2 portion of the project. For the Budget Summary below, please note that the values are burdened values and not raw values, so the actual values going to the entities will be less due to National Laboratory tax costs.

14 SOLAR ENERGY↗

CodeFlow: A Code Generation System for Flash-X Orchestration Runtime

We propose the CodeFlow toolchain for Flash-X that realizes the “recipe-to-source” code transformation for Flash-X simulations and that is necessary to achive performance portability. We design a high-level language to express operations of simulations in so-called recipes, which are given as input to the toolchain. The tools of the CodeFlow pipeline include code transformation with tree-based source code representation techniques and code orchestration and generation based on control flow graphs. The generated source code utilizes a new runtime, developed for Flash-X, that orchestrates dynamic and asynchronous data movement and task execution. The functionality of CodeFlow is demonstrated using a hydrodynamic problem with a strong shock.

97 MATHEMATICS AND COMPUTING↗

Foam Fracturing Study for Stimulation Development of Enhanced Geothermal Systems

The large thermal gradients and high subsurface temperatures of the western region of the U.S. hold great potential for the implementation of enhanced geothermal systems (EGS). The development of these potential EGS resources requires stimulation of the reservoir to enhance permeability and it has been widely reported that a substantial amount of water will be required should conventional hydraulic stimulation be used. This presents a huge challenge and a high risk to the geothermal development because the water stress1 in these areas is already high or extremely high. The use of foam, a gas/liquid mixture predominantly composed of gas, in fracturing is considered and explored in this project as a potential approach to address water concerns with hydraulic stimulation in the development of EGS. This project, led by Oak Ridge National Laboratory (ORNL) in collaboration with Temple University, was awarded in an open lab call in 2018, and was part of the DOE GTO waterless stimulation initiative. The goal of the project was to demonstrate the feasibility of foam fracturing for EGS development through two primary tasks: Task 1: Laboratory study of the effectiveness of foam fracturing for representative geological materials, including cyclic pressurization using foam (led by ORNL) and Task 2: High temperature foam material selection and characterization (led by Temple University). In FY19, ORNL finished the critical review on serval issues associated with foam fracturing and the implementation of the proposed tasks in a lab study (Wang, et al., 2019), and completed the foam fracturing testing using cement as a model material (Wang, et al, 2020a). The work at ORNL was geared up to develop a brand-new foam testing system in FY20. The purchase of main components for the new system was finished in the first half of the FY20. The assembly of the foam testing system and foam fracturing testing were completed in the second half of the FY20 (Wang, et al., 2021a). Task 1 required the development of a test system which can be used to perform hydraulic fracturing of geological specimens with both water and foamed liquids at pressure up to 6,000 psi (41.4 MPa). The system possesses several capabilities that conventional injection systems lack for hydraulic fracturing. In addition to its ability to generate foam with controlled quality, it is capable of cycling pressure levels between specified values up to frequencies of 50 Hz. The latter capability was developed to evaluate the hypothesis that cyclic loading of samples would produce enhanced fracturing. The system consists of two sections: one for foam generation and another for foam injection. The foam is generated through separate control and pressurization of liquid and gas phases with controlled flow rates. The injection section is equipped with a low-flow Coriolis flow that monitors the density of foam to ensure the injection is in the range of target foam quality2. Experimental results of foam fracturing are reported for cylindrical granite specimens using water and aqueous N2 foam as the fracturing fluids. All experiments were performed for unconfined conditions. The effects of injection mode (i.e., monotonic vs cyclic pressurization) on breakdown pressure and failure response sample were investigated using water alone as a fracturing fluid and foams with a range of compositions. It was found that in the case of monotonic injection, the breakdown pressure of granite specimens tended to be slightly higher when fracturing with foam. Additionally, with a foam quality of 90%, the water use can be reduced by 50 to 84%, depending on hole size. On the other hand, it was observed that the breakdown pressure can be brought down to 70% of the monotonic breakdown pressure by using low cycle fatigue. Finally, discussions are presented regarding injectivity and water use reduction.

15 GEOTHERMAL ENERGY↗

Developing Capability for Hydride Moderator Manufacturing to Facilitate Thermal Spectrum Design Options

This report provides a summary of efforts to develop the capability to fabricate massive crack-free yttrium hydride samples to support thermal spectrum design options for the Transformational Challenge Reactor (TCR) in FY2019. The challenges to fabricating massive, crack-free single-phase yttrium hydride are discussed. By using a modified static hydriding system, we have successfully demonstrated the fabrication of crack-free yttrium hydride, guided by the well-established thermodynamics of the binary yttriumhydrogen system. The presence of α-phase yttrium in the fabricated yttrium hydride necessitates employing temperature-pressure isochore cooling at the end of the hydriding process. Thus, a fully programmable hydriding system with continuous hydrogen partial pressure and flow control coordinated with precise temperature control has been designed to facilitate processing of massive, crack-free metal hydrides with the desired H/Y atom ratio. The new system is capable of fabricating yttrium hydride samples that will be used to establish a complete database of yttrium hydride to support the application of yttrium hydride as a high-performance moderator material in the TCR and other nuclear systems.

36 MATERIALS SCIENCE↗

“Hybridizing heat-integrated 3D printed modules with mass manufacturable, low pressure drop fiber sorbents” (Final Report)

The overall objective of this proposal was to research, develop, and evaluate a modular direct air capture (DAC) system that is simple and scalable. This system was based on the adsorption of CO 2 into commercial polyamines supported by porous fiber sorbents, which can be produced at kilometer per hour scales using our pre-pilot spinning line. We have housed these fiber materials in novel 3D printed modular housing systems that provide easy-to-manufacture and localized heat integration and flow control. This hybridization of fiber sorbent technology with modular housing provided several advantages that led to lower air pressure drops, higher sorbent productivity, as well as ease of manufacturing and assembly unrivaled by existing and emerging heat integrated contactor designs. The modular housing was fabricated with the following features, at a minimum: (i) a tapered air intake to reduce pressure drop related to entrance effects, (ii) a structured network of heat transfer channels to enable localized cooling and heating during adsorption and desorption, respectively, and (iii) low pressure drop supports for the fiber sorbents. This hybrid manufacturing approach provides a facile method for taking fiber sorbents from lab scale to pilot scale as it dramatically simplifies the fabrication of heat integrated contactor structures.

42 ENGINEERING↗

High-Temperature Freeze & Leak-Resistant Advanced Molten Salt Valve (Final Project Report)

The overall goal of this investigation was to develop an innovative high-temperature chloride molten salt flow control valve capable of operation up to 750 °C. The team developed an integrated active and passive thermal management system to ensure robust design for freeze-thaw cycles, with either a bellows-sealed configuration, a high-temperature stuffing box, or combination of the two. The STM system is unique in the industry.

14 SOLAR ENERGY↗

Helium recovery system at IB3a

The increasing need for optimal and sustainable use of cryogenic resources to support Fermilab’s scientific mission has highlighted the necessity of improving the Laboratory’s helium management practices. An assessment of cryogenic test facilities identified the Technical Division’s Industrial Building 3a (IB3A) as a key site requiring upgrades to integrate a helium recovery system. The IB3A facility is essential for characterizing and testing superconductors, cables, and coils for various R&D projects, including the US High-Luminosity LHC Accelerator Upgrade Project (AUP), Mu2e, and other external collaborations. Currently, the facility relies on 500 L helium Dewars and vents the vaporized helium directly into the atmosphere, leading to significant helium loss. Given the non-renewable nature of helium, recovering and reusing this resource is critical for the sustainability of Fermilab’s operations. To address this challenge, a project has been initiated to connect IB3A to an existing helium purification station and refrigeration system located in another building via a dedicated pipeline pass over the roof of several buildings. This solution will enable the efficient capture of vented helium, its transfer to the purification station, and subsequent liquefaction for reuse in future operations. The project includes a detailed design phase, specifying the pipeline route, flow control mechanisms, and integration with the existing cryogenic infrastructure, followed by phased implementation and commissioning. By implementing this pipeline connection and upgrading IB3A, Fermilab aims to significantly reduce helium waste, lower operational costs, and align with its commitment to sustainability. This initiative provides a model for resource-efficient cryogenic operations and reinforces the Laboratory’s capacity to support its science mission for the long term.

Porwisiak, D. [Fermilab]↗

Development of High Temperature (>700°C) Molten Salt Pump Technology for Generation 3 Solar Power Tower Systems

Bearings are required for long-shafted pumps historically used in concentrating solar thermal power applications. For molten chloride salts, bearings for such service conditions are not commercially available, nor has a design been demonstrated to work. Therefore, a project was sponsored by the Department of Energy’s Solar Energy Technologies Office for the development and demonstration of a submerged bearing for use in chloride salt pumps. This project’s tasks covered the tribological testing of candidate materials and the design, fabrication, testing, and post-test analysis of full-scale salt-compatible bearings. This work expands upon previous work. The effects of potential particulate in the salt were investigated through tribological bench testing. Through 11 tests, the MgO particulate size and concentration in a molten chloride salt were varied, and the effects on friction, wear rate, and wear characteristics were recorded. Novel journal bearings for chloride salt service were designed and fabricated based on these results. The bearings were of a relevant scale (i.e., for a 1.5 in. pump shaft) to demonstrate the technology with respect to further scale-up. The bearings were made of Haynes 244 and Yttria Partially Stabilized Zirconia. A custom bearing test rig, salt tanks, and associated infrastructure (e.g., heaters, tanks, transfer lines, gas flow control) were designed, procured, and installed. A few issues were encountered in the system fabrication process, resulting in delay of the project schedule. The system was successfully fabricated and assembled. Heating, cover gas, and pump motor systems were integrated into the control logic. This progress of the bearing test system represents a significant step forward towards demonstrating this promising technology. Nevertheless, the project ended before testing of the full-scale bearings could be performed.

14 SOLAR ENERGY↗

Exploring anomalous electron decay in nanosecond repetitively pulsed discharges

Nanosecond pulsed discharges (typical pulse duration of about 10 nanoseconds) have attracted widespread attention due to their wide range of applications in plasma-assisted combustion and aerodynamic flow control, biomedicine, nanotechnology, and materials processing. This project investigated the plasma dynamics of nanosecond discharges in a pin-to-pin configuration using a combined experimental and theoretical modeling approach, leveraging the expertise and resources of Purdue University and the Princeton Collaborative Research Facility (PCRF).

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

Mechanical Solutions Scan Report

Power lines, poles, and towers are the backbone of the United States (U.S.) electric-power grid. These transmission and distribution networks route electricity from generator to loads. The characteristics of these routes are rapidly changing -- trending towards decentralized renewable generation, electric heating, vehicle charging, and large data-center loads. Coupled with aging infrastructure and the increased frequency of extreme weather events, there is concern about the future reliability and transmission capacity of conductors and adjacent components. This scan report seeks to provide an overview of mechanical solutions to challenges caused by extreme weather events associated with components of transmission and distribution infrastructure, including conductor heat sag, ice accumulation, wind, and wildfire. Many options could increase transmission capacity or reliability, and these are at various stages of technological readiness. Some have only been lab tested, while some have been widely deployed in the U.S. or overseas for decades. The solution categories and providers featured in this report are intended to be comprehensive at the time of publication and to serve as a reference for decision-makers concerned about transmission and distribution reliability. There are two other categories of large, complex solutions, which are not covered in this report: replacing existing conductors with advanced conductors and implementing digital grid enhancing technologies. A separate scan report titled “Advanced Conductor Scan Report,” which discusses advanced carbon-core conductors, was published by the Idaho National Laboratory (INL) in 2023. Information on digital technologies, such as dynamic line ratings, power-flow controllers, and other power electronics and communications-based devices, can be found on the Grid- Enhancing Technologies landing page. Mechanical grid-enhancing technologies, or solutions covered in this report, often do not require full equipment replacement and do not rely on digital components. Mechanical technologies are overlooked because they may be older, simpler, or seemingly “more obvious” than digital or carbon-core technologies. However, it is wise to consider mechanical solutions in a thorough evaluation of grid enhancing technology solutions.

24 - POWER TRANSMISSION AND DISTRIBUTION↗

Development and Full Load Demonstration of a 900°C Solid Particle Receiver for Concentrating Solar Power Applications - noLimits

Sandia National Laboratories (SNL) and the German Aerospace Centre (DLR) are world leaders in the joint and separate development of very high temperature next generation solar concentrator systems using solid particles. This project “noLimits” is meant to provide the critical performance information needed to commercialize DLR’s CentRec® solar receiver and ancillary particle systems (conveying systems, storage vessels, flow control equipment etc.) developed at Sandia National Laboratories (SNL). Performance information (at power levels closer to a small scale Concentrating Solar Power (CSP) plant) will be obtained at full load conditions (2.5 MWt ) and at 900 °C-1000 °C particle outlet temperatures at the National Solar Thermal Test Facility (NSTTF) located at SNL. Heliogen was proposed to be joining the project as a commercial partner to provide the commercialization route for this receiver design, if successful, as Heliogen acquired the intellectual property (IP) from DLR.

14 SOLAR ENERGY↗

Intelligent Experiments through Real-Time AI: Fast Data Processing and Autonomous Detector Control for High-Energy Nuclear Experiments

The aim of this project is to develop software and hardware for fast real-time data processing and autonomous detector control and calibration for the sPHENIX and the future EIC experiments. Below summarizes Georgia Tech team efforts in the past year: 1. We developed a real-time clustering algorithm and FPGA-based pipeline architecture for processing fired pixel data from ALPIDE sensors in sPHENIX experiments. Our Columnar Clustering Co-Design introduces a hardware-aware, stream-friendly approach that segments pixel data by column pairs using a Column Pair Clustering (CPC) strategy, followed by Cluster Stitching to merge adjacent subclusters. Implemented in Vitis HLS, the pipeline comprises five stages—read-in, subclustering, stitching, analysis, and write-out—connected by tagged HLS streams with custom end-of-event signaling for robust synchronization. We designed a pipelined dataflow model optimized for throughput, low latency, and minimal buffering, enabling scalable clustering across events of arbitrary size. Our system maintains spatial precision via center-of-mass and shape key extraction and efficiently handles edge cases such as fragmented or nested clusters. Compared against DBSCAN in both software and hardware, our approach demonstrates competitive performance under FPGA constraints. 2. We also conducted a comprehensive algorithm-to-hardware co-design of connected component analysis tailored for sPHENIX experiments, focusing on real-time, low-latency processing using FPGAs and High-Level Synthesis (HLS). Starting from a Python-based particle tracking pipeline, the team translated the core logic—graph traversal via DFS and Union-Find—into an HLS-compatible C++ model, replacing dynamic memory and recursion with static arrays and pipelined control flow. The final design includes a fully streamed and dataflow-compatible Union-Find kernel optimized across five iterations, incorporating loop pipelining, array partitioning, AXI/FIFO interface tuning, and function flattening. Experimental results show up to 14.8× speedup over the CPU baseline, reducing per-graph latency to 1.58 μs and demonstrating strong resource efficiency with only ~7k LUTs and zero BRAM usage. The design maintains functional correctness against the Python reference using a Python-based C-simulation framework and Mean Squared Error metrics. This work validates the potential of HLS-driven FPGA designs for edge-level HEP data acquisition, laying a scalable foundation for future integration with real-time detector pipelines and multi-graph processing systems.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗