Introduction to Monitoring, Control, and Protection Minitrack

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Exploratory analysis of high-resolution power interruption data reveals spatial and temporal heterogeneity in electric grid reliability

Modern grid monitoring equipment enables utilities to collect detailed records of power interruptions. These data are aggregated to compute publicly reported metrics describing high-level characteristics of grid performance. The current work explores the depth of insights that can be gained from public data, and the implications of losing visibility into heterogeneity in grid performance through aggregation. We present an exploratory analysis examining three years of high-resolution power interruption data collected by archiving information posted in real-time on the public-facing website of a utility in the Western United States. We report on the size, frequency and duration of individual power interruptions, and on spatio-temporal variability in aggregate reliability metrics. Our results show that metrics of grid performance can vary spatially and temporally by orders of magnitude, revealing heterogeneity that is not evidenced in publicly reported metrics. We show that limited access to granular information presents a substantive barrier to conducting detailed policy analysis, and discuss how more widespread data access could help to answer questions that remain unanswered in the literature to date. Given open questions about whether grid performance is adequate to support societal needs, we recommend establishing pathways to make high-resolution power interruption data available to support policy research.Comment: Journal submission (in review), 22 pages, 8 figures, 1 tabl

Online Tracking of Two Dominant Inter-Area Modes of Oscillation in the Eastern Interconnection

Reliable power system operation requires that small-signal stability be maintained at all times. Mode meters are measurement-based tools that provide operators with situational awareness of the system's stability margin. They operate by continually tracking the inter-area modes of oscillation that govern small-signal stability. This paper reports on the deployment of mode meters for online monitoring of two dominant modes of oscillation in the United States' Eastern Interconnection (EI). The use of measurements from system operators across the interconnection to provide continuous tracking is novel in the EI. Results from over four months of analysis reveal diurnal patterns in the modes and demonstrate that they can be tracked through a variety of system conditions. The results from this study continue to build an understanding of the EI's modes that will inform future modeling and monitoring efforts

Renewable Resource Integration Project - Scoping Study of Strategic Transmission, Operations, and Reliability Issues

California is on a path to increase utilization of renewable resources. California will need to integrate approximately 30,000 megawatts (MW) of new renewable generation in the next 20 years. Renewable resources are typically located in remote locations, not near the load centers. Nearly two/thirds or 20,000 MW of new renewable resources needed are likely to be delivered to Los Angeles Basin transmission gateways. Integration of renewable resources requires interconnection to the power grid, expansion of the transmission system capability between the backbone power grid and transmission gateways, and increase in delivery capacity from transmission gateways to the local load centers. To scope the transmission, operations, and reliability issues for renewables integration, this research focused on the Los Angeles Basin Area transmission gateways where most of new renewables are likely. Necessary actions for successful renewables integration include: (1) Expand Los Angeles Basin Area transmission gateway and nomogram limits by 10,000 to 20,000 MW; (2) Upgrade local transmission network for deliverability to load centers; (3) Secure additional storage, demand management, automatic load control, dynamic pricing, and other resources that meet regulation and ramping needed in real time operations; (4) Enhance local voltage support; and (5) Expand deliverability from Los Angeles to San Diego and Northern California

Expression of Chimeric HPV-HIV Protein L1P18 in Pichia pastoris; Purification and Characterization of the Virus-like Particles

VPH; Pichia pastoris; PurificaciónVPH; Pichia pastoris; PurificacióHPV; Pichia pastoris; PurificationCurrently, three human papillomavirus (HPV) vaccines are already licensed and all of them are based on virus-like particles (VLPs) of HPV L1 capsid protein but not worldwide accessible. While about 38.0 million people were living with HIV in 2019, only 68% of HIV-infected individuals were accessing antiretroviral therapy as of the end of June 2020 and there is no HIV vaccine yet. Therefore, safe, effective, and affordable vaccines against those two viruses are immediately needed. Both HPV and HIV are sexually transmitted infections and one of the main access routes is the mucosal genital tract. Thus, the development of a combined vaccine that would protect against HPV and HIV infections is a logical effort in the fight against these two major global pathogens. In this study, a recombinant Pichia pastoris producing chimeric HPV-HIV L1P18 protein intracellularly was constructed. After cell disruption, the supernatant was collected, and the VLPs were purified by a combination of ammonium sulfate precipitation, size exclusion chromatography, ultracentrifugation, and ultrafiltration. At the end of purification process, the chimeric VLPs were recovered with 96% purity and 9.23% overall yield, and the morphology of VLPs were confirmed by transmission electron microscopy. This work contributes towards the development of an alternative platform for production of a bivalent vaccine against HPV and HIV in P. pastoris.This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 681137. In addition, we acknowledge support by Instituto de Salud Carlos III (RETIC-RIS RD12/0017, FIS PI14/00494, and FIS PI20/00217), Direcció General de Recerca i Innovació en Salut (DGRIS), Catalan Health Ministry Generalitat de Catalunya, and Centro para el Desarrollo Tecnológico Industrial (CDTI) from the Spanish Ministry of Economy and Business, grant number IDI-20200297

Tracking the Reliability of the U.S. Electric Power System: An Assessment of Publicly Available Information Reported to State Public Utility Commissions

Large blackouts, such as the August 14-15, 2003 blackout in the northeasternUnited States and Canada, focus attention on the importance of reliable electric service. As public and private efforts are undertaken to improve reliability and prevent power interruptions, it is appropriate to assess their effectiveness. Measures of reliability, such as the frequency and duration of power interruptions, have been reported by electric utilities to state public utility commissions for many years. This study examines current state and utility practices for collecting and reporting electricity reliability information and discusses challenges that arise in assessing reliability because of differences among these practices. The study is based primarily on reliability information for 2006 reported by 123 utilities to 37 state public utility commissions

Customer Impact Evaluation for the 2009 Southern California Edison Participating Load Pilot

The 2009 Participating Load Pilot Customer Impact Evaluation provides evidence that short duration demand response events which cycle off air conditioners for less than thirty minutes in a hot, dry environment do not lead to a significant degradation in the comfort level of residents participating in the program. This was investigated using: (1) Analysis of interval temperature data collected from inside residences of select program participants; and (2) Direct and indirect customer feedback from surveys designed and implemented by Southern California Edison at the conclusion of the program season. There were 100 indoor temperature monitors that were acquired by LBNL for this study that transmitted temperature readings at least once per hour with corresponding timestamps during the program season, June-October, 2009. Recorded temperatures were transferred from the onsite telemetry devices to a mesh network, stored, and then delivered to KEMA for analysis. Following an extensive data quality review, temperature increases during each of the thirty demand response test events were calculated for each device. The results are as follows: (1) Even for tests taking place during outside temperatures in excess of 100 degrees Fahrenheit, over 85 percent of the devices measured less than a 0.5 degree Fahrenheit temperature increase indoors during the duration of the event. (2) For the increases that were observed, none was more than 5 degrees and it was extremely rare for increases to be more than 2 degrees. At the end of the testing season SCE and KEMA designed and conducted a survey of the a facilities and public works managers and approximately 100 customers feedback survey to assess the extent the PLP events were noticed or disrupted the comfort level of participants. While only a small sampling of 3 managers and 16 customer surveys were completed, their responses indicate: (1) No customer reported even a moderate level of discomfort from the cycling-off of their air conditioners during test events; and (2) Very few customers noticed any of the thirty events at all. The results of this study suggest that the impacts on comfort from short-duration interruptions of air-conditioners, even in very hot climates, are for the most part very modest, if they are even noticed at all. Still, we should expect that these impacts will increase with longer interruptions of air-conditioning. By the same token, we should also expect that they will be less significant in cooler climates

Engineering new mycobacterial vaccine design for HIV-TB pediatric vaccine vectored by lysine auxotroph of BCG

In this study, we have engineered a new mycobacterial vaccine design by using an antibiotic-free plasmid selection system. We assembled a novel Escherichia coli (E. coli)-mycobacterial shuttle plasmid p2auxo.HIVA, expressing the HIV-1 clade A immunogen HIVA. This shuttle vector employs an antibiotic resistance-free mechanism for plasmid selection and maintenance based on glycine complementation in E. coli and lysine complementation in mycobacteria. This plasmid was first transformed into glycine auxotroph of E. coli strain and subsequently transformed into lysine auxotroph of Mycobacterium bovis BCG strain to generate vaccine BCG.HIVA 2auxo. We demonstrated that the episomal plasmid p2auxo.HIVA was stable in vivo over a 7-week period and genetically and phenotypically characterized the BCG.HIVA 2auxo vaccine strain. The BCG.HIVA 2auxo vaccine in combination with modified vaccinia virus Ankara (MVA). HIVA was safe and induced HIV-1 and Mycobacterium tuberculosis -specific interferon-γ-producing T-cell responses in adult BALB/c mice. Polyfunctional HIV-1-specific CD8+ T cells, which produce interferon-γ and tumor necrosis factor-α and express the degranulation marker CD107a, were induced. Thus, we engineered a novel, safer, good laboratory practice-compatible BCG-vectored vaccine using prototype immunogen HIVA. This antibiotic-free plasmid selection system based on "double" auxotrophic complementation might be a new mycobacterial vaccine platform to develop not only recombinant BCG-based vaccines expressing second generation of HIV-1 immunogens but also other major pediatric pathogens to prime protective response soon after birth