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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Jason Harper, an electrical engineer in Argonne National Laboratory's EV-Smart Grid Interoperability Center, discusses his SpEC Module invention that will enable fast charging of electric vehicles in under 15 minutes. The module has been licensed to BTCPower.
This work has applied a suite of long-term-reliability accelerated tests to a variety of module-level power electronics (MLPE) devices (such as microinverters and optimizers) from five different manufacturers. This dataset is one of the first (only the paper by Parker et al. entitled “Dominant factors affecting reliability of alternating current photovoltaic modules,” in Proc. 42nd IEEE Photovoltaic Spec. Conf., 2015, is reported for reliability testing in the literature), as well as the largest, experimental sets in public literature, both in the sample size (five manufacturers including both dc/dc and dc/ac units and 20 units for each test) and the number of experiments (six different experimental test conditions) for MLPE devices. The accelerated stress tests (thermal cycling test per IEC 61215 profile, damp heat test per IEC 61215 profile, and static temperature tests at 100 and 125 °C) were performed under powered and unpowered conditions. The first independent long-term experimental data regarding damp heat and grid transient testing, as well as the longest term (>9 month) testing of MLPE units reported in the literature for thermal cycling and high-temperature operating life, are included in these experiments. Additionally, this work is the first to show in situ power measurements, as well as periodic efficiency measurements over a series of experimental tests, demonstrating whether certain tests result in long-term degradation or immediate catastrophic failures. Lastly, the result of this testing highlights the performance of MLPE units under the application of several accelerated environmental stressors.
Ten new C100 cryomodules have been fabricated and installed for the CEBAF 12 GeV upgrade in the past few years. The high order modes (HOM) of these modules need to be controlled to avoid beam breakup (BBU) instability. Over the last few years, we surveyed the HOM for all the 80 cavities of the C100 modules in the Vertical Test Area (VTA), as well as in the JLAB Cryomodule Test Facility (CMTF) and the CEBAF tunnel. Additional measures such as waveguide filters were applied to reduce the quality factor of the out of spec modes. In addition, we also measured the same passband modes of all the cavities. In this paper, we will present the HOM survey methodology and results from CMTF and CEBAF survey (not including the VTA survey), as well as the same passband modes. The mitigation measures and their effects will also be discussed.
Second patch release of v2.0.0 Changes since v2.0.1 [Important change] Add and update SSP370 and SSP585 cases, add tests, fix use-case files, Change ocean and sea-ice IC for ARRM60to10. [EAM] allow thetaxx as a CAM_TARGET, enable northamericax4v1pg2_WC14to60E2r3 for AMIP, fix ndrop initialization, allow up to 15 history files. [EAMxx] allow use of readnl [EAM-MMF] allow transient SST case for C++ MMF, remove specific task/thread count for ESMT test, modify the variance transport diagnostic, reorg tests, [HOMME] Allow optional sponge layer. [ELM] add 2 land-atm compsets, update FATES to API 17.0.0, allow FATES sp mode, allow ELM harvest to drive FATES harvest, fix memleaks, reduce test build times, modified parameters for miscanthus and switchgrass based on calibration [MPAS-Ocean] turn on ocean BGC in BGC cases, fix interface locations for 60L PHC grid, add mode spec to conservation check streams, allow oRRS18to6v3 grid to run with JRA, update ocean and sea ice ICs for ARRM60to10 (needed for v2), GPU port of thickness tendency, add CMPASO-JRA1p4, [MPAS framework] Add new reproducible global sum module for MPAS components, Add mostRecentAccessTime attribute to streams [MPAS-landice] Update MALI version and Greenland mesh [MPAS-seaice] add single-cell test case, fix BGC restart, Adds omp critical directives for ice warnings seen on cori. [CIME] Fix component namelist creation bugs when NINST>1, add OpenACC, OpenMP and CXX GPU tests, fix nonBFB tests, stop using config_compilers, reduce ELM test build times with shared executable, update OpenMPI on Chrysalis. fix baseline handling, provenance handling with update to cime6.0.33, also use component-specific config_pes files and add the ones from master [Machine updates] cori modules after maint, Chrysalis to OpenMPI-4.1.3 [run_e3sm] replace default case name and group. [Externals] update SCORPIO to 1.3.2
Abstract All freely available plane‐of‐array (POA) transposition models and photovoltaic (PV) temperature and performance models in pvlib‐python and pvpltools‐python were examined against multiyear field data from Albuquerque, New Mexico. The data include different PV systems composed of crystalline silicon modules that vary in cell type, module construction, and materials. These systems have been characterized via IEC 61853‐1 and 61853‐2 testing, and the input data for each model were sourced from these system‐specific test results, rather than considering any generic input data (e.g., manufacturer's specification [spec] sheets or generic Panneau Solaire [PAN] files). Six POA transposition models, 7 temperature models, and 12 performance models are included in this comparative analysis. These freely available models were proven effective across many different types of technologies. The POA transposition models exhibited average normalized mean bias errors (NMBEs) within ±3%. Most PV temperature models underestimated temperature exhibiting mean and median residuals ranging from −6.5°C to 2.7°C; all temperature models saw a reduction in root mean square error when using transient assumptions over steady state. The performance models demonstrated similar behavior with a first and third interquartile NMBEs within ±4.2% and an overall average NMBE within ±2.3%. Although differences among models were observed at different times of the day/year, this study shows that the availability of system‐specific input data is more important than model selection. For example, using spec sheet or generic PAN file data with a complex PV performance model does not guarantee a better accuracy than a simpler PV performance model that uses system‐specific data.
In the future ATLAS Inner Tracker detector (ITk), several silicon strip modules will be biased by a single High-Voltage (HV) line, so that a switch between each strip sensor and the HV line is required to disconnect faulty sensors. Such a switch must satisfy strict requirements, such as being radiation hard, being able to sustain high voltages in the OFF state and being able to operate in a high magnetic field. At Brookhaven National Laboratory we conceived a new kind of solid-state switch that can potentially meet all the specs: it is a HV silicon vertical JFET. Before designing and fabricating the JFET, we did a study using numerical TCAD simulations that demonstrate the feasibility of fabricating the device in a standard planar technology. As a result, we report such simulations, highlighting in particular a few key parameters to which the JFET performances are most sensitive.
This Final Technical Report describes the work and accomplishments of the project entitled, “Green-House-Gas-Reduced Coal-and-Biomass-to-Liquid-Based Jet Fuel (GHGR-CBTL) Process”. The main objective of the project was to raise the Technology Readiness Level (TRL) of the GHGR-CBTL fuel-production technology from TRL 4 to TRL 5 by producing a drop-in synthetic Jet Propellant 8 (JP-8) with a greenhouse-gas footprint less than or equal to petroleum-based JP-8 by utilizing mixtures of coal and biomass as the feedstock. The system utilizes the patented Altex fuel-production technology, which incorporates advanced catalysts developed by Pennsylvania State University. While the system was not fabricated and tested, major efforts were expended to design the 1-TPD and a full-scale plant. The system was designed, a Block-Flow Diagram (BFD), a Process-Flow Diagram (PFD), and Piping-and-Instrumentation Diagrams (P&IDs) were produced, a Bill of Materials (BOM) and associated spec sheets were produced, commercially available components were selected and procured, custom components were designed and fabricated, catalysts were developed and screened for performance, and permitting activities were conducted. Optimization tests for JP-8 production using C2 olefin as the feed were performed over a range of temperatures, pressures and WHSVs. Liquid yields of between 63 to 65% with 65% JP-8 fraction (41-42% JP-8 yield) at 50 psig were achieved. Life-Cycle Analysis (LCA) was performed by Argonne National Laboratory (ANL), and a GHGR-CBTL module was added to the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET®) model. Based upon the experimental results, the plant design was reconfigured for zero natural-gas imports and minimal electricity imports. The LCA analysis of the reconfigured process utilizing the GREET model showed that if the char from the process was utilized to produce combined heat and power (CHP) then a feed containing 23 wt% biomass and 77 wt% lignite would be needed for parity with petroleum-based JP-8. If the char is not utilized for CHP, but sequestered in a land fill, 24 wt% biomass and 76 wt% lignite would be required. A TEA was performed on this configuration following DOE guidelines and using the ANL-developed GREET module that showed that the GHGR-CBTL TOC and ECO are 69% and 58% of those for the DOE FT-Liquids Baseline Case, respectively. This analysis shows that the economics of the GHGR-CBTL process are significantly better than a gasification/FT process. No technical barriers were identified. The lower costs and the detailed design that was performed under this project are being used by Altex to attract funding partners to move the GHGR-CBTL development forward.
Ceramatec Inc, in collaboration with IntraMicron (IM), the Energy & Environmental Research Center (EERC) and Sustainable Energy Solutions, LLC (SES), have completed a three-year research project integrating their respective proprietary technologies in key areas to demonstrate production of a jet fuel from coal and biomass sources. The project goals and objectives were to demonstrate technology capable of producing a “commercially-viable quantity” of jet fuel and make significant progress toward compliance with Section 526 of the Energy Independence and Security Act of 2007 (EISA 2007 §526) lifecycle greenhouse gas (GHG) emissions requirements. The Ceramatec led team completed the demonstration of nominal 2 bbl/day Fischer-Tropsch (FT) synthesis pilot plant design, capable of producing a nominal 1 bbl/day in the Jet-A/JP-8 fraction. This production rate would have a capacity of 1,000 gallons of jet fuel per month and provide the design basis of a 100 bbl/day module producing over 2,000 gallons of jet fuel per day. Co-gasification of coal-biomass blends enables a reduction of lifecycle greenhouse gas emissions from equivalent conventional petroleum derived fuel basis. Due to limits of biomass availability within an economic transportation range, implementation of a significant biomass feed fraction will require smaller plants than current world scale CTL and GTL FT plants. Hence a down-scaleable design is essential. The pilot plant design leverages Intramicron’s MicroFiber Entrapped Catalyst (MFEC) support which increases the catalyst bed thermal conductivity two orders of magnitude, allowing thermal management of the FT reaction exotherm in much larger reactor tubes. In this project, single tube reactors having 4.5 inch outer diameter and multi-tube reactors having 4 inch outer diameters were operated, with productivities as high as 1.5 gallons per day per linear foot of reactor tube. A significant reduction in tube count results from the use of large diameter reactor tubes, with an associated reduction in reactor cost. The pilot plant was designed with provisions for product collection capable of operating with conventional wax producing FT catalysts but was operated with a Chevron hybrid wax-free FT catalyst. Process simplification enabled by elimination of the wax hydrocracking process unit provides economic advantages in scaling to biomass capable plant sizes. Intramicron also provided a sulfur capture system based on their Oxidative Sulfur Removal (OSR) catalyst process. The integrated sulfur removal and FT systems were operated with syngas produced by the Transport Reactor Development Unit (TRDU) gasifier at the University of North Dakota EERC. SES performed modeling of their cryogenic carbon capture process on the energy, cost and CO2 emissions impact of the Coal-biomass synthetic fuel process.