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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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At least 1,279 records · Page 71

A Review of PJM Interconnection's April 13, 2018, Response to National Energy Technology Laboratory's Report on Reliability, Resilience and the Oncoming Wave of Retiring Baseload Units

In a March 2018 report entitled Reliability, Resilience and the Oncoming Wave of Retiring Baseload Units , the National Energy Technology Laboratory (NETL) analyzed the fleet performance of market areas impacted by a 13-day storm known colloquially as the “Bomb Cyclone.” Special attention was paid to northeastern areas, as these were most impacted. With respect to PJM Interconnection LLC (PJM), the report found that 1) without coal units, the system would have experienced shortfalls; 2) approximately 25 gigawatts (GW) of heretofore underutilized coal-fired plants provided crucial capacity, lending the system resilience; 3) nearly 28 GW of natural gas-fired capacity did not deploy, due to severe spikes in natural gas prices caused in turn by constrained gas deliverability, in the face of tremendous space heating demand and transmission deliverability constraints on the bulk electric system. In April 2018, PJM issued a response that argued the NETL analysis was misplaced, asserting that gas-fired capacity was available and that it could have been called into service but was not, due to “economics.” This brief represents NETL’s reaction to PJM’s assertions in its April 2018 response.

20 FOSSIL-FUELED POWER PLANTS↗

Degradation and Reliability Advancements in Tubular SOFC (Final Report)

The objective of this project is to improve the degradation and reliability of tubular SOFC and develop technologies applicable to stacks scalable to sub-MW system. The Phase II project scope encompasses the cell level technology development listed here and also bundle level degradation verification; 1. Incorporation of an inexpensive on-cell contamination gettering element in each cell to provide protection for cathode against Cr and S; 2. Enhance the electrical contact between Ag current collector and the lanthanum chromite based interconnection layer; 3. Improve the electrolyte layer sintering recipe to reduce the defect density and related anode oxidation problem

03 NATURAL GAS↗

Degradation and Reliability Advancements in Tubular SOFC (Final Report)

The objective of this project is to improve the degradation and reliability of tubular SOFC and develop technologies applicable to stacks scalable to sub-MW system. The Phase II project scope encompasses the cell level technology development listed below and also bundle level degradation verification. (1) Incorporation of an inexpensive on-cell contamination gettering element in each cell to provide protection for cathode against Cr and S. (2) Enhance the electrical contact between Ag current collector and the lanthanum chromite based interconnection layer. (3) Improve the electrolyte layer sintering recipe to reduce the defect density and related anode oxidation problem.

03 NATURAL GAS↗

Metal Bellows Valve Reliability Testing - Copper Stem Tip Testing

SRNL was funded in Mid-Year FY20 by NNSA NA-231 to continue evaluation of alternate valves for use in tritium service to support domestic Mo-99 production. The focus of the effort was to identify valve cycle life as a function of actuator size and stem tip material. Using the minimum size actuator to reliability open and close valves can reduce glovebox size and thus support domestic companies to “come to market” faster in supplying Mo-99 to the US market. This report serves as a continuation to the FY19 report and summarizes the task activities completed in FY20 after authorization to start work was obtained on May 5 th , 2020. Copper stem tips were tested on the Swagelok 1C and 5C actuated metal bellows valves. With ambitions to cycle each set 150,000 times, both 1C and 5C valves were met with high failure rates. The smaller 1C actuated valves required additional closing pressure to form a seal with the Cu stem tips installed however, excessive stem tip deformation may be the root cause of the majority of the valves failing before 500 cycles. The larger 5C actuated valves were cycled 150,000 times but still resulted in 80% failure rate, suspected of metal fatigue in the bellows due to high cycling frequencies.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Gearbox Reliability Collaborative 1.5 (GRC1.5) Project: Joint Industry Megawatt Scale Gearbox Field Tests: Cooperative Research and Development (Final Report) CRADA Number CRD-16-00608

A new DOE/NREL industry collaboration called the Gearbox Reliability Collaborative 1.5 (GRC1.5) will undertake field testing on a commercial multi-megawatt wind turbine gearbox to collect loading data as installed in the turbine to thoroughly characterize gearbox loads and responses during actual in-field conditions. A chief outcome is to provide publicly available operational loading data to the industry. This will provide a greater understanding of steady-state, transient, and fault response for both the input and output of the gearbox; thus, facilitating improvements in the gearbox components, lubrication system, power converter or turbine controller.

17 WIND ENERGY↗

Solutions for Enhanced Legacy Probabilistic Risk Assessment Tools and Methodologies: Improving Efficiency of Model Development and Processing via Innovative Human Reliability Dependency Analysis

Probabilistic risk assessments (PRAs) are integral to nuclear power plant (NPP) operations, having tremendously benefitted the safety of the U.S. reactor fleet for decades. Insights obtained from the models have provided perspectives on a variety of applications, both at the plant and for the regulator. While these models are very useful, they are now being asked to represent and analyze aspects of the plant that were never envisioned by the initial PRA practitioners. Furthermore, heightened demands on the PRA models have led to increased computing power requirements. Additionally, as the complexity of the PRA models increased, the difficulty experienced by non-PRA experts in trying to understand these models, grasp the insights they provide, and effectively use that information has become problematic. The need for research to address key issues regarding PRA tools and methods has never been greater. Although the nuclear power industry has largely been well-served by these tools and methods, the underlying science is dated, remaining mostly unchanged for over two decades. Three areas were identified as most beneficial to address to maintain and improve the usefulness of the current practice legacy PRA tools: improved quantification speed, increased ability to efficiently model multi-hazard models, and improved modeling human action dependency in PRA. This report is focused on the third critical area, improvements in dependency analysis of human actions conducted as part of a typical human reliability assessment.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

Communications Reliability for Vehicle Grid Integration

Electric Vehicles (EVs) adoption rate has been steadily increasing in the US leading to a growing number of charging stations including faster DC (Direct Current) chargers and slower Level 1 and Level 2 AC (Alternating Current) chargers. This increase in demand for electricity is further exacerbated by recent developments in Artificial Intelligence (AI) technology, advanced manufacturing, and digitization. These factors will require electric utilities to upgrade their infrastructure to keep up with the increasing electrical demand (especially during peak hours). An easy way to counteract the need for these upgrades is to shift a major chunk of active charge sessions (durations where there is energy transfer from charger to EV's propulsion battery) to off-peak hours thereby flattening the load curve and making the infrastructure more resilient. This concept is known as Smart Charge Management (SCM). EV owners also benefit from SCM since it lowers their charging costs and consequently their transportation costs by prioritizing charging during off-peak hours. SCM takes advantage of EV's capability to act as a controllable load or DER (Distributed Energy Resource). This report summarizes the reliability analysis performed on the communication required for two of these SCM use-cases. This analysis only focuses on SCM strategies for unidirectional charging (energy transfer from EVSE to EV or V1G) and not bidirectional charging.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Data Center Power Systems: Architectures, Impact on Grid Reliability, Modeling Considerations, and Megawatt-Scale Hardware Testing [Slides]

This slide deck describes typical power systems of large datacenters along with reliability problems to bulk power systems from large-scale integration of datacenters. The slide deck covers the architecture of datacenter power systems, different power electronic converters used inside datacenters, their operation modes, and R&Dopportunities in maintaining grid stability.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Integrated Approach to Ancillary PV Component Reliability Assessment (Final Report)

In this project, we have established a nondestructive, generalized methodology that (1) fuses rich field data with advanced ML for proactive reliability forecasting, (2) dramatically reduces experimental iterations via synthetic dataset generation, and (3) achieves unprecedented regression precision in both anomaly detection and component-level degradation assessment—paving the way for truly predictive maintenance of grid-tied PV inverters under diverse outdoor conditions.

14 SOLAR ENERGY↗

Innovative Interfacial Engineering for Simultaneous Enhancement in Efficiency, Stability, and Reliability in Perovskite Devices

The overarching objective of this project was to increase significantly the mechanical adhesion toughness of the key interfaces in PSCs, thereby improving the durability and reliability of PSCs and minimodules, while simultaneously enhancing their PCE. This is achieved by incorporating rationally-chosen self-assembled monolayers (SAMs) at key PSC interfaces. Inherently scalable methods for the deposition of MHP light-absorber thin films and SAMs are employed to ensure a viable path towards manufacturability. Furthermore, detailed understanding of mechanisms of PSCs and minimodules degradation, and SAMs-induced mitigation, is provided. As part of the project accomplishments, >60% increase in the adhesion toughness of the key PSC interfaces over their SAMs-free control counterparts was achieved. Also, PCEs >20% and >19% in rigid and flexible, respectively, single-junction PSCs (~1 cm 2 area) were achieved. It was shown that <20% PCE loss in flexible PSCs with SAMs can be achieved after bend testing. It was demonstrated that T80 (80% retention of initial PCE) of >5,000 hours in rigid PSCs (~1 cm2 area) can be achieved. Comprehensive understanding of the degradation mechanisms in PSCs was obtained. These strategies were adopted towards developing minimodules. PCE of >21% was obtained in an 6-cm 2 area minimodule, with T91 of 1,000 hours.

14 SOLAR ENERGY↗

Improving the Reliability of Large High-Speed Systems

More reliable protection of large high-speed systems from spontaneous speed increases is considered. To that end, a smart mechatronic module with a system for determining the surface quality of the structural components may be introduced in the automatic safety mechanism. That excludes operator participation in verifying safety-system performance.

42 ENGINEERING↗

An Approach to Dependence Assessment in Human Reliability Analysis: Application of Lag and Linger Effects

Dependence assessment refers to an approach used in human reliability analysis (HRA) to adjust a human error probability (HEP) for the following action by considering the impact of the preceding action. It has been known to significantly affect the overall results of probabilistic safety assessment (PSA). If the dependence assessment is not adequate, the result could be unconvincing for explaining the operator failures in the context of PSA. To date, several methods and some recent research have identified suggestions for treating dependence issues in HRA; however, these are still exclusively based on the intrinsic approach of the Technique for Human Error Rate Prediction (THERP), an HRA method. THERP inevitably has a challenge with the subjectivity of expert evaluation as well as the requirement for PSA and HRA expertise with resource-intensive and time-consuming processes. This paper suggests an approach to dependence assessment that could not only minimize the influence of expert judgment, but also saves time to perform the analysis with reasonable manpower. It modifies existing HRA methods with considering lag and linger effects to apply dependence effects for them. Based on a representative HRA method, i.e., Standardized Plant Analysis Risk - HRA (SPAR-H), guidance for how to apply lag and linger effects for the HRA method is suggested. Then, an investigation is carried out to compare quantification results of the revised HRA method with that of the original approach based on experimental data.

99 GENERAL AND MISCELLANEOUS↗