Search results for "optimization"
showing 10 items of 2824 documents
Sustainability of the Renewable Energy Extraction Close to the Mediterranean Islands
2017
The aim of this work is to explore the possibility of transitioning a fuel powered island to a renewable powered one. This transition is analyzed for the real MV/LV distribution system of the island of Pantelleria, in the Mediterranean Sea. Particularly, this work is focused on a renewable source nowadays totally unused: wave energy. Thanks to the innovative generator prototype designed by Department of Energy of University of Palermo (Italy), wave energy is able to represent a primary source for the production of electric energy in the Mediterranean islands. The procedures applied in the present article, as well as the main equations used, are the result of previous applications made in di…
A state-space approach to mathematical modeling and parameters identification of vehicle frontal crash
2014
In this paper a state-space estimation procedure that relies on the time-domain analysis of input and output signals is used for mathematical modeling of vehicle frontal crash. The model is a double-spring–mass–damper system, whereby the front mass and real mass represent the chassis and the passenger compartment, respectively. It is observed that the dynamic crash of the model is closer to the dynamic crash from experimental when the mass of the chassis is greater than the mass of the passenger compartment. The dynamic crash depends on pole placement and the estimated parameters. It is noted that when the poles of the model are closer to zero, the dynamic crash of the model is far from the…
On the Efficacy of PCM to Shave Peak Temperature of Crystalline Photovoltaic Panels: An FDM Model and Field Validation
2013
The exploitation of renewable energy sources and specifically photovoltaic (PV) devices have been showing significant growth; however, for a more effective development of this technology it is essential to have higher energy conversion performances. PV producers often declare a higher efficiency respect to real conditions and this deviation is mainly due to the difference between nominal and real temperature conditions of the PV. In order to improve the solar cell energy conversion efficiency many authors have proposed a methodology to keep the temperature of a PV system lower: a modified crystalline PV system built with a normal PV panel coupled with a Phase Change Material (PCM) heat stor…
Analytical Investigation and Control System Set-up of Medium Scale PV Plants for Power Flow Management
2012
In the field of photovoltaic (PV) plants and energy conversion from renewable sources, a large part of the technical literature is more devoted to practical aspects (new solar cells, electrically driven PV panels, safety, reduction of parasitic currents, etc.) than to theoretical investigations. Despite this tendency, this paper presents a mathematical analysis of a medium scale photovoltaic power generation system connected to the distribution network and of its control system. In such a system, the conversion stage is unique due to the absence of a boost chopper. The conducted analysis leads to the interesting conclusion that the inverter used in the plant presents two degrees of freedom,…
Economic evaluation on the use of reconfiguration systems for increase of energy production in PV plants
2016
This paper presents an economic analysis of the effectiveness of Dynamic Reconfiguration Systems (DRS) for PV plants in dependence of the incentive policies offered by several countries of the European Community. This evaluation has been achieved by means of the NPV (Net Present Value) and through the comparison between Bulgaria, Romania, Greece and Croatia. From the obtained results, it can be stated that the adoption of reconfiguration systems, in certain cases, can be a convenient solution.
Wave Energy Assessment along Sicilian Coastline, Based on DEIM Point Absorber
2017
The use of renewable energy sources is one of the most relevant goals to be achieved in order to match the climate protection targets. As a case study, the paper shows the current electrical energy production by sources in the Sicilian context. Among the renewable energy sources, the paper investigates the wave energy potential along the Sicilian coasts, because of the favorable climate around the island. A point absorber is present in order to exploit this source. Two scenarios are presented, with two different levels of energy production.
Optimal power flow in islanded microgrids using a simple distributed algorithm
2015
In this paper, the problem of distributed power losses minimization in islanded distribution systems is dealt with. The problem is formulated in a very simple manner and a solution is reached after a few iterations. The considered distribution system, a microgrid, will not need large bandwidth communication channels, since only closeby nodes will exchange information. The correction of generated active powers is possible by means of the active power losses partition concept that attributes a portion of the overall power losses in each branch to each generator. The experimental part shows the first results of the proposed method on an islanded microgrid. Simulation results of the distributed…
Designing a Sustainable University Recharge Area for Electric Vehicles: Technical and Economic Analysis
2017
This article addresses the technical and economic challenges regarding the design of a “green” recharge area for electric vehicles at the University of Palermo in order to reduce costs and pollution connected to the charging process. Based on the behaviour of the student population, the electrical load is identified and two possible solutions are evaluated to manage the peak load: an orientation of the panels increasing the power at defined time and the use of a storage system. The main strength and weakness points of two systems are investigated by taking into account the Levelized Cost of Energy (LCOE), which reaches 75.3 €/MWh for the orientation of panel and 103 €/MWh for the storage sy…
Proof of Concept of an Irradiance Estimation System for Reconfigurable Photovoltaic Arrays
2015
In order to reduce the mismatch effect caused by non-uniform shadows in PV arrays, reconfigurable interconnections approaches have been recently proposed in the literature. These systems usually require the knowledge of the solar radiation affecting every solar module. The aim of this work is to evaluate the effectiveness of three irradiance estimation approaches in order to define which can be well suited for reconfigurable PV arrays. It is presented a real-time solar irradiance estimation device (IrradEst), implementing the three different estimation methods. The proposed system is based on mathematical models of PV modules enabling to estimate irradiation values by sensing a combination …
Evaluation of the Water Scarcity Energy Cost for Users
2013
Abstract: In systems experiencing water scarcity and consequent intermittent supply, users often adopt private tanks that collect water during service periods and supply users when the service is not available. The tank may be fed by gravity or by private pumping stations depending on the network pressure level. Once water resources are collected, the tank can supply users by gravity if it is located on the rooftop or by additional pumping if underground. Private tanks thus increase the energy cost of the water supply service for users by introducing several small pumping structures inside the network. The present paper aims to evaluate this users’ energy cost for different private tank con…