Increasing distributed generation hosting capacity in distributionsystems via optimal coordination of electric vehicle aggregators

This work presents a novel strategy, designed from the distribution system operator view-point, aimed at estimating the hosting capacity in electric distribution systems when con-trollable plug-in electric vehicles are in place. The strategy seeks to determine the maxi-mum wind-based distributed generation penetration by coordinating, on a forecast basis,the dispatch of electric vehicle aggregators, the operation of voltage regulation devices,and the active and reactive distributed generation power injections. Different from previ-ous works, the proposed approach leverages controllable features of electric vehicles takinginto account technical electric vehicle characteristics, driving behaviour of electric vehicleowners, and electric vehicle energy requirements to accomplish their primary purpose. Thepresented strategy is formulated as a two-stage stochastic mixed-integer linear program-ming problem. The first stage maximises the distributed generation installed capacity, whilethe second stage minimises the energy losses during the planning horizon. Probability den-sity functions are used to describe the uncertainties associated with renewable distributedgeneration, conventional demand, and electric vehicle driving patterns. Obtained resultsshow that controlling the power dispatched to electric vehicle aggregators can increase thedistributed generation hosting capacity by up to 15% (given a 40% electric vehicle penetra-tion), when compared to an uncontrolled electric vehicle approac

Evaluación de precios de contrato de generación distribuida: una metodología basada en teoría de juegos

The main objective of this research is the contract pricing calculation of distributed generation (DG) considering its interaction with the distribu­tion company. The proposed methodology consists in modeling the DG energy trading using game theory concepts and bilevel programming. To validate the proposed methodology several tests are carried out with a 34 bus distribution system, changing the number and size of the DGunits. The contract prices calculated with this methodology represent an equilibrium between the profit maximization pursued by the DG owner and the minimization of payments procured by the distribution company. Consequently, it can be concluded that the proposed methodology provides efficient incentives for both agents, providing a solution in which the DG and the distribution company are mutually beneficial. Furthermore, the location of the DG units can also be considered in the model, so that not only the contract price but also the equilibrium location can be found.El objetivo principal de esta investigación consiste en calcular los precios de contrato de la generación distribuida (GD) considerando su interacción con la compañía distribuidora. La metodología propuesta consiste en modelar la dinámica de compra y venta de energía de GD usando conceptos de teoría de juegos y programación binivel. Para validar la metodología propuesta se realizaron varias pruebas en un sistema de distribución de 34 barras cambiando el número y el tamaño de las unidades de GD. Los precios de contrato calculados con esta metodología representan un equilibrio entre la maximización de utilidades que busca el propietario de la GD y la minimización de pagos que busca la empresa distribuidora. De esta forma, se concluye que la metodología propuesta en este artículo provee incentivos eficientes para ambos agentes, entregando una solución en la que la GD y la empresa distribuidora se benefician mutuamente. Adicionalmente, la ubicación de las unidades de GD también puede considerarse dentro del modelo y de esta manera encontrar, no solo el precio de contrato, sino también la ubicación de equilibrio

Ubicación y dimensionamiento óptimo de generación distribiuda en sistemas de energía eléctrica

En este artículo se presenta una metodología para ubicación y dimensionamiento óptimo de generación distribuida (GD) en sistemas de energía eléctrica. Las barras candidatas para ubicar GD son identificadas basándose en los precios marginales locales. El problema de ubicación óptima es formulado para dos objetivos: la maximización del beneficio social líquido y la maximización del lucro (este último desde el punto de vista del propietario de la GD). Para las unidades de GD se asumieron diferentes características de costo y para cada unidad se identificó la localización y el dimensionamiento óptimo para cada uno de los objetivos. La metodología propuesta es evaluada en el sistema IEEE de 14 barras

Ubicación y dimensionamiento óptimo de generación distribiuda en sistemas de energía eléctrica

En este artículo se presenta una metodología para ubicación y dimensionamiento óptimo de generación distribuida (GD) en sistemas de energía eléctrica. Las barras candidatas para ubicar GD son identificadas basándose en los precios marginales locales. El problema de ubicación óptima es formulado para dos objetivos: la maximización del beneficio social líquido y la maximización del lucro (este último desde el punto de vista del propietario de la GD). Para las unidades de GD se asumieron diferentes características de costo y para cada unidad se identificó la localización y el dimensionamiento óptimo para cada uno de los objetivos. La metodología propuesta es evaluada en el sistema IEEE de 14 barras

Ubicación y dimensionamiento óptimo de generación distribiuda en sistemas de energía eléctrica

En este artículo se presenta una metodología para ubicación y dimensionamiento óptimo de generación distribuida (GD) en sistemas de energía eléctrica. Las barras candidatas para ubicar GD son identificadas basándose en los precios marginales locales. El problema de ubicación óptima es formulado para dos objetivos: la maximización del beneficio social líquido y la maximización del lucro (este último desde el punto de vista del propietario de la GD). Para las unidades de GD se asumieron diferentes características de costo y para cada unidad se identificó la localización y el dimensionamiento óptimo para cada uno de los objetivos. La metodología propuesta es evaluada en el sistema IEEE de 14 barras

Videolaparoscopic Radical Hysterectomy Approach: a Ten-Year Experience

Videolaparoscopic radical hysterectomy was found to have comparable operative times, lymph node retrieval, and complications as those reported by others

Molecular Epidemiology of mcr-Encoded Colistin Resistance in Enterobacteriaceae From Food-Producing Animals in Italy Revealed Through the EU Harmonized Antimicrobial Resistance Monitoring

Colistin resistance by mobilisable mcr genes has been described in bacteria of food-animal origin worldwide, which has raised public health concerns about its potential foodborne transmission to human pathogenic bacteria. Here we provide baseline information on the molecular epidemiology of colistin-resistant, mcr-positive Escherichia coli and Salmonella isolates in food-producing animals in Italy in 2014-2015. A total 678, 861 and 236 indicator E. coli, Extended Spectrum Beta-Lactamase (ESBL)/AmpC-producing E. coli, and Salmonella isolates, respectively, were tested for colistin susceptibility. These isolates were collected according to the EU harmonized antimicrobial resistance monitoring program and are representative of at least 90 and 80% of the Italian poultry (broiler chickens and turkeys) and livestock (pigs and bovines < 12 months) production, respectively. Whole genome sequencing by Illumina technology and bioinformatics (Center for Genomic Epidemiology pipeline) were used to type 42 mcr-positive isolates by PCR. Colistin resistance was mainly observed in the ESBL/AmpC E. coli population, and was present in 25.9, 5.3, 6.5, and 3.9% of such isolates in turkeys, broilers, pigs, and bovines, respectively. Most colistin-resistant isolates (141/161, 87.5%) harbored genes of the mcr-1 group. mcr-1 was also detected in a small proportion of Salmonella isolates (3/146, 2.0%) in turkeys. Additional mcr types were mcr-3 in four ESBL-producing E. coli from bovines, and two mcr-4 in ESBL (n = 1) and indicator E. coli (n = 1) from pigs and bovines. We describe notable diversity of mcr variants with predominance of mcr-1.1 and mcr-1.2 on conjugative IncX4 plasmids in E. coli and in Salmonella serovars Typhimurium, Newport, Blockley from turkey. A new variant, mcr-1.13 was detected in the chromosome in E. coli in turkey and pig isolates. Additionally, we describe mcr-3.2 and mcr-4.3 in E. coli from bovines, and mcr-4.2 in E. coli from pigs. These findings elucidate the epidemiology of colistin resistance in food-producing animals in Italy along with its genetic background, and highlight the likelihood of mcr horizontal transfer between commensal bacteria and major food-borne pathogens (Salmonella) within the same type of productions. Thorough action and strategies are needed in order to mitigate the risk of mcr transfer to humans, in a “One Health” perspective

Ubicación óptima de generación distribuida en sistemas de energía eléctrica

This article presents a methodology for the optimal location of distributed generation in electric power systems. Candidate bars to locate distributed generation are identified based on local marginal prices. These prices are obtained by solving an optimal power flow (OPF) and correspond to the Lagrange multipliers of the active power balance equations in each of the system bars. To include distributed generation in the OPF, it has been modeled as a negative injection of active power. The methodology consists of an iterative nonlinear process where distributed generation is located in the bar with the highest marginal price. Three types of distributed generation were considered: 1) internal combustion engines, 2) gas turbines and 3) microturbines. The proposed methodology is evaluated in the 30-bar IEEE system. The results obtained show that distributed generation contributes to the reduction of nodal prices and can help solve congestion problems in the transmission network.En este artículo se presenta una metodología para la ubicación óptima de generación distribuida en sistemas de energía eléctrica. Las barras candidatas para ubicar la generación distribuida son identificadas basándose en los precios marginales locales. Estos precios son obtenidos al resolver un flujo de potencia óptimo (OPF) y corresponden a los multiplicadores de Lagrange de las ecuaciones de balance de potencia activa en cada una de las barras del sistema. Para incluir la generación distribuida en el OPF, ésta se ha modelado como una inyección negativa de potencia activa. La metodología consiste en un proceso no lineal iterativo en donde la generación distribuida es ubicada en la barra con el mayor precio marginal. Se consideraron tres tipos de generación distribuida: 1) motores de combustión interna, 2) turbinas a gas y 3) microturbinas. La metodología propuesta es evaluada en el sistema IEEE de 30 barras. Los resultados obtenidos muestran que la generación distribuida contribuye a la disminución de los precios nodales y puede ayudar a solucionar problemas de congestión en la red de transmisión

Emergence of a Clonal Lineage of Multidrug-Resistant ESBL-Producing Salmonella Infantis Transmitted from Broilers and Broiler Meat to Humans in Italy between 2011 and 2014

We report the spread of a clone of multidrug-resistant (MDR), ESBL-producing (blaCTX-M-1) Salmonella enterica subsp. enterica serovar Infantis, in the Italian broiler chicken industry and along the food-chain. This was first detected in Italy in 2011 and led to human infection in Italy in 2013-2014.A set (n = 49) of extended-spectrum cephalosporin (ESC)-resistant (R) isolates of S. Infantis (2011-2014) from humans, food-producing animals and meat thereof, were studied along with a selected set of earlier and more recent ESC-susceptible (ESC-S) isolates (n = 42, 2001-2014). They were characterized by macrorestriction-PFGE analysis and genetic environment of ESC-resistance. Isolates representative of PFGE-patterns and origin were submitted to Whole Genome Sequencing. The emerging ESC-R clone, detected mainly from broiler chickens, broiler meat and humans, showed a minimum pattern of clinical resistance to cefotaxime, tetracycline, sulfonamides, and trimethoprim, beside ciprofloxacin microbiological resistance (MIC 0.25 mg/L). All isolates of this clone harbored a conjugative megaplasmid (~ 280-320 Kb), similar to that described in ESC-susceptible S. Infantis in Israel (pESI-like) in 2014. This megaplasmid carried the ESBL gene blaCTX-M-1, and additional genes [tet(A), sul1, dfrA1 and dfrA14] mediating cefotaxime, tetracycline, sulfonamide, and trimethoprim resistance. It also contained genes conferring enhanced colonization capability, virulence (fimbriae, yersiniabactin), resistance and fitness (qacE1, mer) in the intensive-farming environment. This emerging clone of S. Infantis has been causing infections in humans, most likely through the broiler industry. Since S. Infantis is among major serovars causing human infections in Europe and is an emerging non-typhoidal Salmonella globally, further spread of this lineage in primary productions deserves quick and thorough risk-management strategies