A review on the complementarity of renewable energy sources: concept, metrics, application and future research directions

It is expected, and regionally observed, that energy demand will soon be covered by a widespread deployment of renewable energy sources. However, the weather and climate driven energy sources are characterized by a significant spatial and temporal variability. One of the commonly mentioned solutions to overcome the mismatch between demand and supply provided by renewable generation is a hybridization of two or more energy sources in a single power station (like wind-solar, solar-hydro or solar-wind-hydro). The operation of hybrid energy sources is based on the complementary nature of renewable sources. Considering the growing importance of such systems and increasing number of research activities in this area this paper presents a comprehensive review of studies which investigated, analyzed, quantified and utilized the effect of temporal, spatial and spatio-temporal complementarity between renewable energy sources. The review starts with a brief overview of available research papers, formulates detailed definition of major concepts, summarizes current research directions and ends with prospective future research activities. The review provides a chronological and spatial information with regard to the studies on the complementarity concept.Comment: 34 pages 7 figures 3 table

A review on the complementarity of renewable energy sources: Concept, metrics, application and future research directions

Global and regional trends indicate that energy demand will soon be covered by a widespread deployment of renewable energy sources. However, the weather and climate driven energy sources are characterized by a significant spatial and temporal variability. One of the commonly mentioned solutions to overcome the mismatch between demand and supply provided by renewable generation is a hybridization of two or more energy sources into a single power station (like wind-solar, solar-hydro or solar-wind-hydro). The operation of hybrid energy sources is based on the complementary nature of renewable sources. Considering the growing importance of such systems and increasing number of research activities in this area this paper presents a comprehensive review of studies which investigated, analyzed, quantified and utilized the effect of temporal, spatial and spatiotemporal complementarity between renewable energy sources. The review starts with a brief overview of available research papers, formulates detailed definition of major concepts, summarizes current research directions and ends with prospective future research activities. The review provides a chronological and spatial information with regard to the studies on the complementarity concept

Triazole Fungicide Prosaro EC 250 - induced Hematologicaland Biochemical Alterations in Male Rabbits (Oryctolagus Cuniculus)

The study aimed to evaluate the toxic effects of fungicide Prosaro 250 EC on hematological profiles and renal functional-biochemical markers, as well as blood glucose level .Twenty-four male rabbits were equally and randomly divided into control untreated group (G1) (n =6) received distilled water and standard food, and three treated groups (n=6 each) received by oral gavage Prosaro 250 EC at three doses (mg/kg body weight (bw)), 0.093 (G2), 0.186 (G3) and 0.465 mg/kg bw (G4) for 21 days .Results revealed a significant decrease in the kidney weight, and a significant increase in the levels of serum urea, uric acid, creatinine, and glucose in Prosaro treated groups compared with the control group. Moreover, Prosaro-induced hematotoxicity was evidenced by a marked decline inred blood cell counts (RBC), hemoglobin (HGH) and hematocrit (HT) levels, along with a significant increase in white blood cell (WBC) and platelet count. Thus the sub-chronic toxicity of Prosaro 250 EC is proved to induce hematological and biochemical alterations in rabbits

Heavy Metals Assessment in the Medjerda River Basin (Northeastern Algeria): A Preliminary Water Analysis and Toad Skin Biopsy

AbstractOur study attempted to monitor the quality of water in Medjarda basin (Northeastern Algeria) and to provide baseline information of heavy metals in the water as well as in a potential amphibian biosentinel, the spiny toad, Bufo spinosus. We measured pH, temperature, dissolved oxygen and biological oxygen demand of water and levels of heavy metals in toad skin using an atomic absorption flame spectrophotometer. Lead (Pb) concentration in water and in toad skin at all sites exceeded respectively 60 and 96 times the standard reference values. The heavy metal concentrations, in descending order, in water and in male toad skin were as follows: Pb > Fe > Cu > Zn and Fe > Pb > Zn > Cu respectively. This study highlights the ecological status of the surrounding areas upstream of the Medjarda basin as being a point source of heavy metal pollution. It is further stated that a non-invasive skin removal is an ethically sound technique to evaluate heavy metal accumulation in aquatic animals like toad, without euthanizing the specimens and making any loss to biodiversity of the species

Heavy Metals Assessment in the Medjerda River Basin (Northeastern Algeria): A Preliminary Water Analysis and Toad Skin Biopsy.

Our study attempted to monitor the quality of water in Medjarda basin (Northeastern Algeria) and to provide baseline information of heavy metals in the water as well as in a potential amphibian biosentinel, the spiny toad, Bufo spinosus. We measured pH, temperature, dissolved oxygen (DO) and biological oxygen demand (BOD) of water and levels of heavy metals in toad skin using an atomic absorption flame spectrophotometer. Lead (Pb) concentration in water and in toad skin at all sites exceeded respectively 60 and 96 times the standard reference values. The heavy metal concentrations, in descending order, in water and in male toad skin were as follows: Pb>Fe> Cu> Zn and Fe> Pb>Zn>Cu respectively. This study highlights the ecological status of the surrounding areas upstream of the Medjarda basin as being a point source of heavy metal pollution. It is further stated that a non-invasive skin removal is an ethically sound technique to evaluate heavy metal accumulation in aquatic animals like toad, without euthanizing the specimens and making any loss to biodiversity of the species

Complementarity of wind and solar power in North Africa: Potential for alleviating energy droughts and impacts of the North Atlantic Oscillation

With growing gas and oil prices, electricity generation based on these fossil fuels is becoming increasingly expensive. Furthermore, the vision of natural gas as a transition fuel is subject to many constraints and uncertainties of economic, environmental, and geopolitical nature. Consequently, renewable energies such as solar and wind power are expected to reach new records of installed capacity over the upcoming years. Considering the above, North Africa is one of the regions with the largest renewable resource potential globally. While extensively studied in the literature, these resources remain underutilized. Thus, to contribute to their future successful deployment and integration with the power system, this study presents a spatial and temporal analysis of the nature of solar and wind resources over North Africa from the perspective of energy droughts. Both the frequency and maximal duration of energy droughts are addressed. Both aspects of renewables’ variable nature have been evaluated in the North Atlantic Oscillation (NAO) context. The analysis considers the period between 1960 and 2020 based on hourly reanalysis data (i.e., near-surface shortwave irradiation, wind speed, and air temperature) and the Hurrel NAO index. The findings show an in-phase relationship between solar power and winter NAO index, particularly over the coastal regions in western North Africa and opposite patterns in its eastern part. For wind energy, the connection with NAO has a more zonal pattern, with negative correlations in the north and positive correlations in the south. Solar energy droughts dominate northern Tunisia, Algeria, and Morocco, while wind energy droughts mainly occur in the Atlas Mountains range. On average, solar energy droughts tend not to exceed 2–3 consecutive days, with the longest extending for five days. Wind energy droughts can be as prolonged as 80 days (Atlas Mountains). Hybridizing solar and wind energy reduces the potential for energy droughts significantly. At the same time, the correlation between their occurrence and the NAO index remains low. These findings show the potential for substantial resilience to inter-annual climate variability, which could benefit the future stability of renewables-dominated power systems.Graphical abstrac

Cost-reliability analysis of hybrid pumped-battery storage for solar and wind energy integration in an island community

This paper presents a mathematical model for estimating the optimal sizing and assessing a standalone hybrid power system's performance entirely based on variable renewable energy sources and coupled with a hybrid energy storage system. This study evaluates how different levels of the main components' capital cost and the loss of power supply probability would affect the cost of energy and the power system's optimal sizing. The case study selected for this study was Ometepe Island in Nicaragua, where the crater lake of an extinct volcano was considered a feasible upper reservoir of a pumped storage hydropower plant, reducing the investments associated with this component. The mathematical formulation considers energy storage losses and gains, and the Pareto efficient solutions of the multi-objective optimization model simultaneously increase reliability, reduce the cost of energy, and minimize curtailment energy. By employing time-series with an hourly resolution, the model allows assessing the impact of the interannual variability of renewable energy sources on the system's performance. As for the case study, the cost of energy obtained from the model results ranges between €0.047/kWh and €0.095/kWh, based on international reference values, and these values match the information available in the literature and other databases

Contribution to the indoor power line grid modeling to characterize the PLC propagation channels

Le réseau électrique s'utilise aujourd'hui comme support de transmission des signaux Ethernet. C’est le concept des courants porteurs en ligne. Cette technique de transmission permet d’obtenir des débits supérieurs au Wifi. Cependant, la complexité des réseaux électriques et l'environnement électromagnétique domestique peuvent dégrader les performances de cette technologie. L’environnement électrique de l'habitat avec ses appareils électroménagers divers en font un milieu difficilement maitrisable. L’objectif est d’appréhender et de modéliser cet environnement et le comportement des équipements qui y sont déployés. Pour cela, ce mémoire présente plusieurs méthodes pour modéliser les lignes électriques dans l'habitat. Les modélisations existantes sont difficilement généralisables à un réseau électrique quelconque. Nous proposons une modélisation de type circuit électrique.Son intérêt réside dans la simplicité de l'outil de simulation d'un réseau électrique, réalisé parla mise en cascade de plusieurs blocs intégrés à la librairie SPICE. Les blocs SPICE proposés prennent en compte la dépendance fréquentielle des paramètres des quadripôles. Une étape de caractérisation expérimentale est développée pour implémenter ces blocs. Un réseau expérimental de test, constitué de différentes technologies de câble, a été caractérisé en termes de bruit, d'impédance et de pertes d'insertion. Le rayonnement émis lors d'une transmission CPL a également été mesuré.The power line grid is used for data transmission by means of the broad band powerline communication systems (BPLC) The main advantage of this technology consists in providing an existing infrastructure of wires and wall sockets that are easy to access throughout a building and offering physical data rates comparable with other existing communication technologies such as Wi-Fi. Nevertheless, the power line grid complexity, the various connected household appliances and the housing electromagnetic environment,impact the PLC transmission performances. As results the housing environment is not a controllable medium. The objective of the current thesis is to study the electromagnetic environment of the Indoor power line network, and to model the potential impacts of both the power line grid topology and the household devices on the PLC physical layer. The existing modeling approaches require a deduction of theirs parameters from the measurements and cannot be generally applied. We propose a new model based on circuitry approach. Its main interest consists in the simplicity of the simulation tool of power line grid which is based on series symmetric SPICE circuit integrated to SPICE library. To this aim, the characterization of the power cable, of the electrical accessories and household devices is necessary. The impedance of powered household devices is measured according to simple measurement protocol. The proposed model takes into account the variation of the whole primary parameters of the electrical cable as function of frequency. An experimental characterizationof the so called PLC READY test bench was carried out in terms of noise, impedance and insertion loss. The radiated electromagnetic field during a PLC communication is measured

Contribution à la modélisation du réseau électrique domestique en vue de la caractérisation du canal de propagation CPL

The power line grid is used for data transmission by means of the broad band power line communication systems (BPLC) The main advantage of this technologie consists in providing an existing infrastructure of wires and wall sockets that are easy to access throughout a building and offering physical data rates comparable with other existing communication technologies such as Wifi. Neverthless, the power line grid complexity, the various connected household appliances and the housing electromagnetic environnement, impact the PLC transmission perfermances.As results the housing environnement is not a controllable medium. The objective of the current thesis is to study the electromagnetic environnement of the Indoor power line network, and to model the potential impacts of both the power line grid topology and the household devices on the PLC physical layer. The existing modeling appraoches require a deduction of theirs parametres from the measurements and can not be applied generaly. We propose a new model based on circuitry approach. Its main interest consists in the simplicity of the simulation tool of power line grid which is based on series symmetric SPICE circuit integrated to SPICE library. To this aim, the characterization of the power cable, of the electrical accessories and household devices is necessay. The impedance of powered household devices is measured according to simple measurement protocol. The proposed model tackes into accoint the variation of the whole primary parameters of the electrical cable as function of frequency. An experimental characterization of the so called PLC READY test bench was carried out in terms of noise, impedance and insertion losse. The radiated elecromagnetic field during a PLC communication is measured.Le réseau électrique s'utilise aujourd'hui comme support de transmission des signaux Ethernet. C'est le concept des courants porteurs en ligne. Cette technique de transmission permet d'obtenir des débits supérieurs au Wifi. Cependant, la complexité des réseaux électriques et l'environnement électromagnétique domestique peuvent dégrader les performances de cette technologie. L'environnement électrique de l'habitat avec ses appareils électroménagers divers en font un milieu difficilement maitrisable. L'objectif est d'appréhender et de modéliser cet environnement et le comportement des équipements qui y sont déployés. Pour cela, ce mémoire présente plusieurs méthodes pour modéliser les lignes électriques dans l'habitat. Les modélisations existantes sont difficilement généralisables à un réseau électrique quelconque. Nous proposons une modélisation de type circuit électrique. Son intérêt réside dans la simplicité de l'outil de simulation d'un réseau électrique, réalisé par la mise en cascade de plusieurs blocs intégrés à la librairie SPICE. Les blocs SPICE proposés prennent en compte la dépendance fréquentielle des paramètres des quadripôles. Une étape de caractérisation expérimentale est développée pour implémenter ces blocs. Un réseau expérimental de test, constitué de différentes technologies de câble, a été caractérisé en termes de bruit, d'impédance et de pertes d'insertion. Le rayonnement émis lors d'une transmission CPL a aussi été mesuré

Techno-Economic and Environmental Analysis of a Hybrid PV-WT-PSH/BB Standalone System Supplying Various Loads

The Algerian power system is currently dominated by conventional (gas- and oil-fueled) power stations. A small portion of the electrical demand is covered by renewable energy sources. This work is intended to analyze two configurations of renewables-based hybrid (solar⁻wind) power stations. One configuration was equipped with batteries and the second with pumped-storage hydroelectricity as two means of overcoming: the stochastic nature of the two renewable generators and resulting mismatch between demand and supply. To perform this analysis, real hourly load data for eight different electricity consumers were obtained for the area of Mostaganem. The configuration of hybrid power stations was determined for a bi-objective optimization problem (minimization of electricity cost and maximization of reliability) based on a multi-objective grey-wolf optimizer. The results of this analysis indicate that, in the case of Algeria, renewables-based power generation is still more expensive than electricity produced from the national grid. However, using renewables reduces the overall CO2 emissions up to 9.3 times compared to the current emissions from the Algerian power system. Further analysis shows that the system performance may benefit from load aggregation