Optimal generation dispatch model for prosumer smart grids with pumped hydro storage

Abstract: A promising solution to smart grid stability and reliability issues resulting from the influx of renewable sources, like wind and solar, is the incorporation of pumped hydro storage (PHS). Hence, it is important to investigate the benefits of adding PHS to power grids. To this end, a model for the day-ahead economic generation dispatch of a smart grid with prosumers and pumped hydro storage is formulated. The model is tested using modified data for Ontario’s power system. It is specified and solved with the Advanced Interactive Multidimensional Modelling System (AIMMS). An economic power output schedule for the gas-fired and PHS units in the grid is obtained. Also, the effect of the ramp rate of gas-fired units on grid operating cost is investigated; it is observed that the operating cost reduces with increase in ramp rate

Epsilon-constraint method for solution to the combined economic and emission dispatch problem

Abstract: System operators are concerned with the economics of power system operation as well as the amount of harmful gases released during power generation. The combined economic and emission dispatch (CEED) determines the power output of each online thermal unit for which the operational cost and emissions are at their minimum. It is a multi-objective optimization problem (MOOP) with equality and inequality constraints. In this paper, the epsilon-constraint method is used to tackle the CEED problem. The General Algebraic Modelling Systems (GAMS), known for its speed and ability to handle large and complex power system optimization problems is used to solve the problem formulation. A six-generator test system is taken as the case study in this paper, to verify the CEED mathematical formulation. In comparison with results in literature, the proposed solution method yields lower operational costs

Clinical Study The Prevalence and Antibiotic Susceptibility Pattern of Salmonella typhi among Patients Attending a Military Hospital in Minna, Nigeria

The threat to human health posed by antibiotic-resistant bacterial pathogens is of growing concern to medical practice. This study investigated the antibiotic sensitivity pattern of Salmonella typhi isolated from blood specimen. One hundred blood samples were collected from suspected typhoid fever patients in 31 Artillery Brigade Medical Centre, Minna, and were analyzed for S. typhi while antibiotic sensitivity testing was done Kirby-Bauer method. Sixty (60.0%) samples out of the total 100 were positive for bacterial growth. The organisms isolated 2 include Salmonella typhi; 45 (75.0%), Shigella; 6 (10.0%), E. coli; 3 (5.0%), Klebsiella; 3 (5.0%), Enterobacter; 2 (3.3%), and Citrobacter; 1 (1.7%). Result of the sensitivity test showed that the isolates were resistant to all the antibiotics; ceftriaxone, cefuroxime, amoxicillin, ampicillin, ciprofloxacin, and augmentin, which are the drug of choice routinely used in the study area for the treatment of typhoid fever. They were however sensitive to chloramphenicol and ofloxacin, which, unfortunately, are not used in this study area for the treatment of typhoid fever. There appear to be multiple drug resistant (MDR) strain of S. typhi in the study area. These may be as a result of overdependence or uncontrolled use of the few available antibiotics and/or inaccurate or inconclusive diagnosis resulting in the development and spread of resistant strains of S. typhi. The study, therefore, highlights the need for a strong collaboration between the physicians and the laboratory in the choice of antibiotics for the treatment of bacterial diseases in order to discourage the development of resistant strain of bacterial pathogen

Impact of the Purdue Improved Cowpea Storage Technology on the Income of Cowpea Farmers in North Central Nigeria

The objective of the study was to determine the potential impact of Purdue improved cowpea storage (PICS) technology on the income of users in north central states of Nigeria. A multi-stage sampling procedure involved selection of 3 Local Government Areas (LGAs) each from 18 senatorial districts of six states, 108 villages. Thereafter 2,220 cowpea PICs stakeholders comprising 1,240 farmers and 960 traders were randomly selected by balloting technique. The study used primary data and structured questionnaire to interview users and non-users of PICS bag. Descriptive statistics, double difference estimator, propensity score matching (PSM) and logic model were used to analyze the data. The result showed a positive mean difference of ₦1,205.12 per 50 kg bag (p<0.01) in income between users and non-users before and after adoption of PICS technology. The result of logit model revealed that variables age, education status, employment status, income and quantity of cowpea used in the analysis were significant at different level of probability. The PSM adjusted with constant coefficient value of 1.000 was statistically significant at 1% level. Thus, the PICS technology was a better strategy adopted by farmers/traders to increase their income and improve their standard of living. Since majority of farmers and traders are young and educated, trainings, workshops and sensitization should be encouraged. This can be effectively done through Agricultural Development Programmes (ADP), Non-Governmental Organizations (NGOs) and attending farmer’s stakeholders meeting for sensitization. Keywords — Cowpea, impact, Propensity Score Matching (PSM), Purdue.

Towards Blockchain-Based Energy Trading: A Smart Contract Implementation of Energy Double Auction and Spinning Reserve Trading

The decentralization of power generation driven by the rise in the adoption of distributed energy resources paves the way for a new paradigm in grid operations. P2P energy trading is beneficial to the grid as well as the connected peers. A blockchain-based smart contract is well suited to transparently facilitate trades between energy consumers and producers without the services of intermediaries. In this paper, Ethereum-based smart contracts that facilitate double energy auction and spinning reserve trading are developed with Solidity, compiled, and deployed within the Remix IDE. Willing energy sellers/buyers submit offers/bids to a contract that implements the double auction procedure. In order to fulfil energy supply obligations, sellers are also able to purchase spinning reserves via another smart contract. The smart contracts’ effectiveness in performing the auction procedure and making payments is confirmed using an energy/reserve market scenario. The proposed scheme encourages further adoption of distributed energy resources and participation in local P2P energy trading

The Prevalence and Antibiotic Susceptibility Pattern of Salmonella typhi among Patients Attending a Military Hospital in Minna, Nigeria

The threat to human health posed by antibiotic-resistant bacterial pathogens is of growing concern to medical practice. This study investigated the antibiotic sensitivity pattern of Salmonella typhi isolated from blood specimen. One hundred blood samples were collected from suspected typhoid fever patients in 31 Artillery Brigade Medical Centre, Minna, and were analyzed for S. typhi while antibiotic sensitivity testing was done Kirby-Bauer method. Sixty (60.0%) samples out of the total 100 were positive for bacterial growth. The organisms isolated 2 include Salmonella typhi; 45 (75.0%), Shigella; 6 (10.0%), E. coli; 3 (5.0%), Klebsiella; 3 (5.0%), Enterobacter; 2 (3.3%), and Citrobacter; 1 (1.7%). Result of the sensitivity test showed that the isolates were resistant to all the antibiotics; ceftriaxone, cefuroxime, amoxicillin, ampicillin, ciprofloxacin, and augmentin, which are the drug of choice routinely used in the study area for the treatment of typhoid fever. They were however sensitive to chloramphenicol and ofloxacin, which, unfortunately, are not used in this study area for the treatment of typhoid fever. There appear to be multiple drug resistant (MDR) strain of S. typhi in the study area. These may be as a result of overdependence or uncontrolled use of the few available antibiotics and/or inaccurate or inconclusive diagnosis resulting in the development and spread of resistant strains of S. typhi. The study, therefore, highlights the need for a strong collaboration between the physicians and the laboratory in the choice of antibiotics for the treatment of bacterial diseases in order to discourage the development of resistant strain of bacterial pathogen

Diverse Metabolic Capacities of Fungi for Bioremediation

Bioremediation refers to cost-effective and environment-friendly method for converting the toxic, recalcitrant pollutants into environmentally benign products through the action of various biological treatments. Fungi play a major role in bioremediation owing to their robust morphology and diverse metabolic capacity. The review focuses on different fungal groups from a variety of habitats with their role in bioremediation of different toxic and recalcitrant compounds; persistent organic pollutants, textile dyes, effluents from textile, bleached kraft pulp, leather tanning industries, petroleum, polyaromatic hydrocarbons, pharmaceuticals and personal care products, and pesticides. Bioremediation of toxic organics by fungi is the most sustainable and green route for cleanup of contaminated sites and we discuss the multiple modes employed by fungi for detoxification of different toxic and recalcitrant compounds including prominent fungal enzymes viz., catalases, laccases, peroxidases and cyrochrome P450 monooxygeneses. We have also discussed the recent advances in enzyme engineering and genomics and research being carried out to trace the less understood bioremediation pathways