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At least 217 records · Page 12

Conceptual design of inverted core lead bismuth eutectic fast reactor for marine applications

The development of an inverted core fast reactor aims to generate 60 MWth for about 30 Effective Full Power Years without refueling. The reactor design is a transportable reactor using UO{sub 2} fuel and lead-bismuth-eutectic cooled designed for marine applications and is intended to improve the reactor performances compared to the normal core design: better condition for passive cooling system capability by lower core pressure drop, taking advantage of potential power uprate from the lower maximum fuel temperature. Systematic design processes are presented in this work: fuel pin geometry selection, fuel assembly (FA) design, and core design. A relationship between pressure drops, coolant velocity, maximum fuel temperature, coolant channel diameter, and fuel volume fraction was introduced in a single graph used as a tool to select fuel pin geometry. Fuel fabrication capability also took place in consideration of FA design which led to 7 holes per FA, and two-dimensional temperature distribution studies were also carried out. Core design processes including radial zoning, axial zoning, and core optimization were conducted using Monte Carlo code MCS, which is UNIST CORE laboratory in-house code. The current core design uses 3 fuel enrichment levels and 3 FA types to control the local power distribution and power shift during its lifetime. (authors)

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

Design of the ITER ICRF Antenna

The CYCLE consortium has been designing the ITER ICRF antenna since March 2010, supported by an F4E grant. Following a brief introduction to the consortium, this paper: describes the present status and layout of the design; highlights the key mechanical engineering features; shows the expected impact of cooling and radiation issues on the design and outlines the need for future R and D to support the design process. A key design requirement is the need for the mechanical design and analysis to be consistent with all requirements following from the RF physics and antenna layout optimisation. As such, this paper complements that of Durodie et al.

42 ENGINEERING↗

Conceptual Design of a Tension Leg Platform With 22.3 MW Vertical Axis Turbine

Here, this paper presents the conceptual design of a tension leg platform (TLP) for the ARCUS “towerless” vertical-axis wind turbine (VAWT). VAWTs are ideal for floating offshore sites and have several advantages over horizontal-axis wind turbines (HAWT) including reduced top mass, lower center of gravity, increased energy capture, and in turn lower cost. The towerless ARCUS VAWT drives these advantages further through increased structural efficiency and by enabling more optimized TLP designs with simplified installation procedures. For hull sizing, we have studied three turbine sizes with corresponding power ratings of 5.1 MW, 10.4 MW and 22.3 MW. The largest turbine was identified as having the greatest potential to reduce the levelized cost of energy (LCOE) and is the reference size used for the further detailed design process. The conceptual design of the VAWT TLP has been awarded with an ABS Approval in Principle Certificate. This paper contains brief analysis results and design findings for a TLP designed to house a VAWT, including the following topics: • Applicable Design Codes • Metocean Conditions • ARCUS Turbine Loads • Design Load Cases and Requirements - Pre-service TLP Stability - In-place TLP Global Performance • Platform Configurations, Hull Structure Scantling Design, Weight and CG Estimation, and General Arrangement Drawings • Hull Ballast Plan for both Pre-service and In-place Conditions • Pre-service Quayside Integration, Transportation and Wet Tow Stability Analysis • Global Performance Analysis for Motions and Tendon tensions • Summary of cost components and system levelized cost of energy

17 WIND ENERGY↗

Gearbox Reliability Collaborative Phase 3 Gearbox 2 Test Plan

Gearboxes in wind turbines have not been achieving their expected design life even though they commonly meet or exceed the design criteria specified in current design standards. One of the basic premises of the National Renewable Energy Laboratory (NREL) Gearbox Reliability Collaborative (GRC) is that the low gearbox reliability results from the absence of critical elements in the design process or insufficient design tools. Key goals of the GRC are to improve design approaches and analysis tools and to recommend practices and test methods resulting in improved design standards for wind turbine gearboxes that lower the cost of energy (COE) through improved reliability. The GRC uses a combined gearbox testing, modeling and analysis approach, along with a database of information from gearbox failures collected from overhauls and investigation of gearbox condition monitoring techniques to improve wind turbine operations and maintenance practices. Testing of Gearbox 2 (GB2) using the two-speed turbine controller that has been used in prior testing. This test series will investigate non-torque loads, high-speed shaft misalignment, and reproduction of field conditions in the dynamometer. This test series will also include vibration testing using an eddy-current brake on the gearbox's high speed shaft.

17 WIND ENERGY↗

Advanced Energy Approaches for Mixed-Use Developments in the Front Range Urban Corridor

The primary objective of the document is to present example technical approaches and strategies that planners and developers can reference for all-electric mixed-use developments in the Rocky Mountain Front Range urban corridor that are considering advanced energy performance goals such as high levels of energy efficiency and renewable integration. The strategies are tailored toward the vision for a zero energy, all-electric, district thermal system-connected starter district. In this example, on-site solar generation is emphasized as a strategy that can be combined with electrical and thermal energy storage for enhanced community resilience and demand flexibility. Opportunities for utilizing or adapting these strategies include: sharing with vertical developers for potential integration of strategies into vertical design guidelines; incorporation into Owner Project Requirements (OPRs); providing example strategies to design teams as a starting point for design; informing structure of agenda for a building design charrette; comparing building designs to example strategies at various points in the design process to evaluate design progression. While the technical strategies outlined in this document can help inform the development of guidelines for projects in the Front Range urban corridor, this document does not set requirements for any rating, certification, program, or policy.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Looking Beyond Energy Efficiency: An Applied Review of Water Desalination Technologies and an Introduction to Capillary-Driven Desalination

Most notable emerging water desalination technologies and related publications, as examined by the authors, investigate opportunities to increase energy efficiency of the process. In this paper, the authors reason that improving energy efficiency is only one route to produce more cost-effective potable water with fewer emissions. In fact, the grade of energy that is used to desalinate water plays an equally important role in its economic viability and overall emission reduction. This paper provides a critical review of desalination strategies with emphasis on means of using low-grade energy rather than solely focusing on reaching the thermodynamic energy limit. Herein, it is argued that large-scale commercial desalination technologies have by-and-large reached their engineering potential. They are now mostly limited by the fundamental process design rather than process optimization, which has very limited room for improvement without foundational change to the process itself. The conventional approach toward more energy efficient water desalination is to shift from thermal technologies to reverse osmosis (RO). However, RO suffers from three fundamental issues: (1) it is very sensitive to high-salinity water, (2) it is not suitable for zero liquid discharge and is therefore environmentally challenging, and (3) it is not compatible with low-grade energy. From extensive research and review of existing commercial and lab-scale technologies, the authors propose that a fundamental shift is needed to make water desalination more affordable and economical. Future directions may include novel ideas such as taking advantage of energy localization, surficial/interfacial evaporation, and capillary action. Here, some emerging technologies are discussed along with the viability of incorporating low-grade energy and its economic consequences. Finally, a new process is discussed and characterized for water desalination driven by capillary action. The latter has great significance for using low-grade energy and its substantial potential to generate salinity/blue energy.

Ahmadvand, Seyedsaeid (ORCID:000000017888262X)↗

Processing and Device Oriented Approach to CIGS Module Reliability; SunShot Initiative, U.S. Department of Energy (DOE)

Abstract: A device level understanding of thin film module reliability has been lacking. We propose that device performance and stability issues are strongly coupled and simultaneous attention to both is necessary. Commonly discussed technical issues such as light soaking, metastability, reverse bias breakdown and junction breakdown can be understood by comparing the behaviors of cells made inAbstract: A device level understanding of thin film module reliability has been lacking. We propose that device performance and stability issues are strongly coupled and simultaneous attention to both is necessary. Commonly discussed technical issues such as light soaking, metastability, reverse bias breakdown and junction breakdown can be understood by comparing the behaviors of cells made in the laboratory and industry. It will then be possible to attribute the observed effects in terms of processing and cell design. Process connection to stability studies can help identify root causes and a path for mitigating the degradation.

14 SOLAR ENERGY↗

Performance of a Dual Fluidized Bed Reactor for Chemical Looping Combustion with Oxygen Uncoupling

Chemical looping with oxygen uncoupling (CLOU) is a variant of chemical looping combustion which uses as fluidized bed particles specific solid oxygen carriers which readily liberate gaseous oxygen (O2) in the fuel reactor. This enables much more efficient combustion of solid fuels such as coal than conventional chemical looping combustion, which relies on in situ gasification of char in to produce syngas that can react heterogeneously with the solid oxygen carrier. The CLOU process for coal is an especially interesting application of fluidized bed technology since several types of reactions take place within the reactors. For copper-based oxygen carrier particles, the copper cycles between cuprous and cupric oxide (Cu2O + ½ O2 ↔ 2 CuO). Volatiles released from coal during pyrolysis may react with oxidized copper or with released oxygen gas. Char reacts primarily with released oxygen. Balancing oxygen supply to the fuel reactor, heat generation and temperatures and global and internal circulation rates is a challenge. The University of Utah has been researching CLOU technology for 10 years, studying fundamental reaction kinetics for copper-based CLOU oxygen carriers, performing lab- and bench-scale experiments in single and dual fluidized beds, and developing reactor models through computational fluid dynamic modeling using Barracuda VR™. Recently the university began testing a 200 kWth dual circulating fluidized bed process development unit (PDU) for processing coal. The design process for that reactor, reactor simulations, operational experience and practical challenges of the PDU system are presented.

Whitty, Kevin J.↗

Low Regeneration Temperature Sorbents for Direct Air Capture of CO 2

Susteon Inc., in partnership with University of Wyoming and SoCalGas, successfully met all major technical objectives to (1) scale up the ionic liquid catalyst for amine-based sorbents for improved desorption and absorption kinetics, (2) evaluate the catalyzed amine-based sorbents for direct CO 2 capture process to determine CO 2 adsorption and desorption rates and energy requirements, and (3) based on the experimental results, develop a conceptual process design to perform a preliminary economic assessment to evaluate the potential for DAC process cost reduction using the catalyzed sorbents. Amine doped solid sorbents are effective for DAC applications and can be regenerated by heat or by a combination of heat, steam, and vacuum. The best sorbent composition identified was polyethyleneimine (PEI) on fumed silica with 200 ppm ionic liquid catalyst. This sorbent formulation was shown to have a CO 2 breakthrough capacity twice that of the non-catalyzed sorbent, in laboratory tests with air at 75% relative humidity (RH). The CO 2 adsorption rate was also 40% higher than that of the non-catalyzed sorbent. This type of sorbents has the attributes required for lowering the overall cost of DAC with high CO 2 capacity and high rate of adsorption. The combination of an industrially utilized amine-based sorbent with a highly active catalyst to form a new class of materials for DAC provides a technically viable pathway for reducing the cost of DAC to <$100/tonne of CO 2 . Laboratory measurements show that the silica/PEI (polyethyleneimine) sorbents with 100 ppm of ionic liquid catalyst have almost 100% higher CO 2 cyclic capacity and 40% higher adsorption rate. Generally, CO 2 desorption occurred at higher temperatures with a rate of desorption 10 times faster than adsorption (which occurred at ambient conditions). Therefore, adsorption rate is a much more important factor in the cost of DAC because it is directly linked to the CAPEX of the total system and the cycle time (i.e., sorbent productivity in ton/day of CO 2 captured per unit volume of the air contactor). An initial process design, coupled with techno-economic analysis, based on optimal experimental results and preliminary resulting from structured sorbent testing, showed a path to lower the DAC cost from the current cost of over $200/tonne CO 2 to less than $100/tonne with a scale-up, mature state of the technology, with projected material and process improvements. These results demonstrate the effectiveness of the catalyst in silica/PEI sorbents in enhancing sorbents’ CO 2 working capacity, in (a) increasing the rate of adsorption and desorption, and (b) in lowering the CAPEX and OPEX of the DAC system employing the ionic liquid catalyzed sorbents.

01 COAL, LIGNITE, AND PEAT↗

Gasification Combined Heat and Power from Coal Fines

The goal of this final project report is to comprehensively summarize the work for public domain conducted on project DE-FE 0031520. In accordance with the Statement of Project Objectives (SOPO), the University of Kentucky Center for Applied Energy Research (UKy-CAER) (Recipient) has completed a Front End Engineering Design (FEED) study 5 MWe polygeneration unit using the Coal Fields Regional Industrial Park in Hazard, Kentucky (KY) as a model location and using coal recovered from the adjacent Pads Branch Impoundment as feed. The scope of work is a thorough study that can be used as a template for the application of the proposed technology throughout Eastern KY and other coal communities nationwide. The Technology Design Basis was developed based on three elements: basic site characteristics; fuel feedstock; and environmental health and safety requirements. The Basic Engineering Design Elements include the preliminary process design (the process area descriptions; the Block Flow Diagram (BFD), Process Flow Diagrams (PFDs) and Piping and Instrumentation Diagrams (P&IDs), process simulation outputs and Heat and Mass Balance (H&MB) stream tables, the major process equipment and instrumentation lists which includes specifications and materials of construction); the cost estimate (capital cost estimate, operational cost estimate, and comparison with state-of-the-art commercial scale similar technologies, options to lower cost, construction cost and schedule estimate); and other supporting elements (guidelines for execution and management of the project), logistical summary, and balance of plant summary, the Environmental Health and Safety (EH&S) assessment; and a Social and Economic Impact (S&EI) assessment. All project milestones, deliverables and success criteria were met. The proposed 5 MWe polygeneration facility being fed from impoundment recovered coal has been shown to be technically feasible. Annual revenues are estimated at $\$ $2.4M from electricity, steam and hydrocarbon production; annual operating expenses are $\$ $5.2M ($\$ $2.9 M in operating expenses, and $\$ $2.4M in indirect expenses). The gasifier facility, as configured during the FEED, will lose money when operating under commercial operating conditions and terms. However, eight options improving the economics can be considered during the detailed design phase to make the facility profitable by taking advantage of the positive differential of revenue to variable operating costs, and reducing the influence of fixed operating costs. Coupled with the findings from the S&EI assessment estimating a total economic impact of $\$ $374M for the proposed polygeneration facility at >$\$ $1.5B, if three additional such projects are implemented, clearly positive economics are demonstrated. No EH&S issues are identified that would prohibit proceeding with the project, although permitting efforts are estimated to take 3-5 years.

01 COAL, LIGNITE, AND PEAT↗

Investigation of thermochemical biorefinery sizing and environmental sustainability impacts for conventional supply system and distributed pre-processing supply system designs

The 2011 US Billion-Ton Update estimates that by 2030 there will be enough agricultural and forest resources to sustainably provide at least one billion dry tons of biomass annually, enough to displace approximately 30% of the country's current petroleum consumption. A portion of these resources are inaccessible at current cost targets with conventional feedstock supply systems because of their remoteness or low yields. Reliable analyses and projections of US biofuels production depend on assumptions about the supply system and biorefinery capacity, which, in turn, depend upon economic value, feedstock logistics, and sustainability. A cross-functional team has examined combinations of advances in feedstock supply systems and biorefinery capacities with rigorous design information, improved crop yield and agronomic practices, and improved estimates of sustainable biomass availability. A previous report on biochemical refinery capacity noted that under advanced feedstock logistic supply systems that include depots and pre-processing operations there are cost advantages that support larger biorefineries up to 10 000 DMT/day facilities compared to the smaller 2000 DMT/day facilities. This report focuses on analyzing conventional versus advanced depot biomass supply systems for a thermochemical conversion and refinery sizing based on woody biomass. The results of this analysis demonstrate that the economies of scale enabled by advanced logistics offsets much of the added logistics costs from additional depot processing and transportation, resulting in a small overall increase to the minimum ethanol selling price compared to the conventional logistic supply system. While the overall costs do increase slightly for the advanced logistic supply systems, the ability to mitigate moisture and ash in the system will improve the storage and conversion processes. In addition, being able to draw on feedstocks from further distances will decrease the risk of biomass supply to the conversion facility.

99 GENERAL AND MISCELLANEOUS↗

RISK-INFORMED BALANCING OF SAFETY, NONPROLIFERATION, AND ECONOMICS FOR THE SFR

A substantial barrier to the implementation of Sodium-cooled Fast Reactor (SFR) technology in the short term is the perception that they would not be economically competitive with advanced light water reactors. With increased acceptance of risk-informed regulation, the opportunity exists to reduce the costs of a nuclear power plant at the design stage without applying excessive conservatism that is not needed in treating low risk events. In the report, NUREG-1860, the U.S. Nuclear Regulatory Commission describes developmental activities associated with a risk-informed, scenario-based technology neutral framework (TNF) for regulation. It provides quantitative yardsticks against which the adequacy of safety risks can be judged. We extend these concepts to treatment of proliferation risks. The objective of our project is to develop a risk-informed design process for minimizing the cost of electricity generation within constraints of adequate safety and proliferation risks. This report describes the design and use of this design optimization process within the context of reducing the capital cost and levelized cost of electricity production for a small (possibly modular) SFR. Our project provides not only an evaluation of the feasibility of a risk-informed design process but also a practical test of the applicability of the TNF to an actual advanced, non-LWR design. The report provides results of five safety related and one proliferation related case studies of innovative design alternatives. Applied to previously proposed SFR nuclear energy system concepts We find that the TNF provides a feasible initial basis for licensing new reactors. However, it is incomplete. We recommend improvements in terms of requiring acceptance standards for total safety risks, and we propose a framework for regulation of proliferation risks. We also demonstrate methods for evaluation of proliferation risks. We also suggest revisions to scenario-specific safety risk acceptance standards, particularly concerning seismic and aircraft impactrelated risks. Most importantly, within the context of the TNF historical SFR safety concerns about energetic core disruptive accidents are seen to be unimportant, but those of rare scenarios mentioned above are seen to be of dominant concern. In terms of proliferation risks the SFR energy system is seen not to be of considerably greater concern than with other nuclear power technologies, providing that highly effective safeguards are employed. We find the economic performance of proposed SFRs likely, due to the problems of using sodium as a coolant, to be inferior to those of LWRs unless they can be credited for services to improve nuclear waste disposal, nuclear fuel utilization and proliferation risk reductions. None of the design innovations investigated offers the promise to reverse this conclusion. The most promising innovation investigated is that of improving the plant's thermodynamic efficiency via use of the supercritical CO{sub 2} (rather than steam Rankine) power conversion system. We were unable to reach conclusions about the economic and proliferation risk implications of competing nuclear fuel processing methods, as available designs are too little developed to justify any such results. Overall, we find the SFR to be a promising alternative to LWRs should the conditions governing the valuation change substantially from current ones.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Maintaining a Flat Li Surface during the Li Stripping Process via Interface Design

Electroplating has been the main focus in mitigating the dendrite growth on the Li-metal electrode; however, the stripping process is equally critical, since the nonsmooth Li surface during stripping will lead to nonuniform local current density, planting the seeds for dendrite growth. In this paper, density functional theory (DFT) and kinetic Monte Carlo (KMC) techniques were combined to investigate the vacancy evolution in Li interfaced with different solid–electrolyte interphase (SEI) materials. It was found that the lithiophilic interface, such as Li/Li 2 O, repels vacancies into the bulk Li, so Li atoms can quickly fill the Li vacancies near the Li/Li 2 O interface and maintain a smooth Li surface. In contrast, the lithiophobic interface, such as Li/LiF, traps Li vacancies toward the interface, and the accumulated Li vacancies form voids and roughen the surface. The predicted critical stripping current density, below which a smooth Li surface will be maintained, is therefore much faster at the lithiophilic interface than that at the lithiophobic interface. It was further revealed that the lithiophilicity at different SEI or coating materials can be ranked as Li/Li 2 O > Li/LiPON > Li/Li 2 CO 3 > Li/LiF based on the calculated interfacial adhesion and accumulation of electron density at the interface. Furthermore, this suggests that interface and coating design at nanoscale can be effective for maintaining a smooth Li surface during the stripping process, solving another challenge to achieving a dendrite-free Li-metal electrode in both liquid and solid electrolytes.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Fuel element design and analysis for potential LEU conversion of the Advanced Test Reactor

This study provides a summary of the status of the design process for a low-enrichment replacement for the high-enrichment fuel that has historically been used in the Advanced Test Reactor (ATR) at Idaho National Laboratory. Under current long-term Department of Energy policy, the ATR will be converted to operate using low-enrichment fuel by 2030. To this end, an engineering evaluation and design process has been underway for more than ten years. Initially performed as a series of scoping studies for different design options, the last five years have seen a transition to a formal Safety-in-Design approach to the design and safety evaluation process. This paper focuses on such efforts in progress since 2012 to identify pre-conceptual and conceptual design candidates for ATR conversion. The Enhanced LEU Fuel (ELF) design is selected as the most promising conceptual design. Analyses and trade-off studies performed that led to that selection are described. Analysis of certain aspects of core performance for an ELF-fueled core relative to the current high-enrichment fuel show that only small and manageable changes to core operations will be necessary to support conversion of ATR to low-enrichment fuel.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

Example Evaluation of a Representative Heat Pipe Test Article Design for Structural Acceptability using ASME Design Rules

This report describes a design analysis of a test article mimicking a core block of a heat-pipe mi-croreactor using the ASME Boiler & Pressure Vessel Code Section III, Division 5, Subsection HB, Subpart B rules. These rules cover the design and construction of elevated temperature nu-clear reactor structural components, like the core block of a heat-pipe microreactor emulated by the test article. The purposes of the report are to: (1) provide a step-by-step example of applying the ASME rules to a reasonable core block geometry and corresponding loading conditions, (2) to provide design feedback on the test article, and (3) to evaluate the ASME rules for use in the design of complex heat-pipe microreactor components. The test article design has a relatively short ASME design life, limited by high thermal stresses. The current ASME rules are adequate for evaluating the core block component designs, though they could be optimized to increase the design efficiency and reduce the amount of designer/analyst time required to execute the design process. The report covers both the current, 2019 edition ASME rules and modified, currently unapproved, rules designed to improve the design process for components with complex geometries and high secondary stresses, like the core block test article.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

Simulating Buildings While the Design is Still in the Architect's Imagination

Very early in the design process, prior to drawing a single line, architects get information from their client or prospective client trying to understand the nature and requirements of the building that needs to be designed. The design of the building is completely fluid, as the architect considers many options in their imagination. The overall massing of the building, the general shape and form, are being considered during this early step. Even for a simple box-shaped building, the aspect ratio between the east-west and the north-south dimensions of the building can greatly impact energy consumption due to daylighting availability. The prevailing winds and building orientation can impact natural ventilation. The locations of high and low population density spaces can also impact energy use. Deciding the floor area per office workstation or the size of the auditorium will impact energy use. Does making a building two stories instead of one reduce energy impacts by reducing roof area or does the additional volume for stairs and elevators result in more energy use. Since certain types of spaces require more windows for occupants than others, the locations of those spaces will determine how much glazing each building orientation has impacting daylighting as well as heating and cooling energy. The project was an attempted first step toward creating a system tailored toward architects for this very early stage in the design process to help them understand the energy impacts of design options. The approach was not to be based on drawing the building, and instead, the main inputs would have been the size of each type of space in the building. This report describes information gathered during the development that might be of use to others developing similar software as well as some of the software that was developed during the project. Phase II funding to continue this work was not pursued due to intellectual property issues discovered during the development of the commercialization plan.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Transforming Aeration Energy in Water Resource Recovery Facilities (WRRFs) through Suboxic Nitrogen Removal (Final Report)

The objective of this project was to advance two key technological components—aeration control strategies and process design methodologies—to support the development and broader adoption of suboxic biological nitrogen removal (SBNR). The project focused on achieving the following three goals: • Enhance Model Predictive Control (MPC) Technology: Advance the DO/Nmaster MPC platform from its initial 2018 pilot deployment at the Chico Water Resource Recovery Facility in California to full-scale integration. This included partnering with a blower technology commercialization partner and incorporating machine learning (ML) capabilities to enable nationwide deployment. • Bridge Knowledge Gaps in SBNR Process Design: Address fundamental gaps in SBNR process understanding through controlled pilot-scale testing at a dedicated pilot facility. These efforts supported the development of robust kinetic models to inform reliable SBNR control, operational strategies, and design frameworks. • Demonstrate Full-Scale Implementation of Low DO/SBNR with ML: Transition low dissolved oxygen (DO)/SBNR coupled with ML from pilot-scale trials to full-scale demonstration in flow-through biological nutrient removal (BNR) systems, with the goal of enabling scalable, nationwide adoption in activated sludge treatment processes. The project included demonstration of SBNR at the pilot scale as performed by Hampton Roads Sanitation District (HRSD) and at the full-scale as performed by the Los Angeles County Sanitation Districts' (LACSD) Pomona Water Reclamation Plant (POWRP).

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

ML-ACCEPT: Machine-Learning-enhanced Automated Circuit Configuration and Evaluation of Power Converters

This project, ML-ACCEPT, took a significant step toward achieving the first objective of the DIFFERENTIATE program: to help engineers to more rapidly and cost-effectively consider a wider range of more novel concepts before selecting an engineering-optimal architecture for high-fidelity detailed design and evaluation. Compared to existing methods, the ML-ACCEPT project investigated innovative technologies to make the design of power converters more cost-effective and time-efficient by i) integrating recent breakthroughs in ML, power electronics, simulation software, and optimization to research, develop, and developed a suite of ML-enhanced hypothesis generation tools for power converter design; and ii) facilitating the integration of the proposed software tools into existing power-converter design work-flows. Some existing tools for power-converter design have a certain level of intelligence to aid the design process, but to our knowledge none of them has ML-enhanced capability of automating the electrical circuit design process by selecting, configuring, and tailoring the individual components that enable available resources (e.g., high-voltage DC power) to be converted to the desired output (e.g., lower-voltage DC power with a desired voltage ripple), subject to application-specific (e.g., plasma generation and automotive applications) thermal and packaging considerations. The state-of-the-art circuit design of power converters is still heavily reliant on human experts to select the optimal topology and search for design parameters with human’s experience and intuitions, which can be very time-consuming, inefficient, and labor intensive. The team is composed of University of Michigan-Dearborn (UM-Dearborn), Lawrence Livermore National Laboratory (LLNL), Oak Ridge National Laboratory (ORNL), Modelon Inc., and lighthouse customers.

42 ENGINEERING↗