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In the present paper, a new approach to the management of energy resources in the Research and Technology Centre of Energy (CRTEn -Tunisia) is proposed and evaluated by the monitoring of a PV installation realized for the cooperation project DE.DU.ENER.T, using renewable energy and economic criteria. The aim of this project is to improve energy efficiency order to minimize the electricity cost consumed at the CRTEn laboratory. According to the bills of electricity received, we noticed that there is a high consumption of electrical current. So, we targeted to install a photovoltaic field of 12KWc to reduce these bills by using the sustainable, green and clean sources. A theoretical study of the PV system sizing realized in order to know in the first hand the compatibility between the different equipment of this installation and to compare the results with those found by the SMA Sunny Design and PV*SOL software in the second hand. The experimental results show that the performance factor of the proposed system is 84.6%. Meanwhile, the cost of the energy generated by the proposed system is 0.045 USD/kWh, which means that the payback period, is about 11 years. The conclusion from this study is that the price of energy generated by PV systems in Tunisia is lower than the subsidized price of energy generated by fossil fuel.

The paper presents the analysis of some potentially suitable actions for reducing the energy losses of an islanded Medium Voltage distribution network, with the aim of improving electricity distribution efficiency. For this purpose, four actions are considered: 1) increasing the network's rated voltage; 2) reactive power compensation through static capacitor banks; 3) reactive power compensation through switchable capacitor banks; 4) installation of distributed photovoltaic (PV) generation. The first two measures are typically taken into account by the distribution system operators and can be examined by means of classical design methods, whereas the latter two more innovative actions are tested here using specialized software based on the NSGA-II multi-objective optimization algorithm. The fourth action, expanding distributed PV generation, can be motivated through public or private incentives. It is investigated here using an innovative approach to the optimization problem formulation considering the perspectives of both the utility and the consumer. A case study on a small Mediterranean island real existing network is also presented.

The feed-in tariff(s) mechanism involves an obligation on the part of an electricity provider to purchase electricity generated by renewable energy sources in its relevant area, paying a tariff determined by public authorities and guaranteed for a specific time period. Feed-in tariff(s) have been the primary mechanism used for supporting the development of renewable energy sources in the EU and, up to date, they are being applied in 20 EU Member Countries. On 6 July 2013, the Italian experience with feed-in tariff(s) for photovoltaic systems finished. During its lifetime of eight years, this incentive mechanism, named “Conto Energia”, was characterized by periods of great success followed by others of serious skepticism. The implementation of the Italian feed-in tariff(s) mechanism was changed many times, becoming very close to the European standard.

In the present paper, a new approach for the management of energy resources in a research laboratory is proposed and evaluated. A simulation study for the photovoltaic (PV) installation was conducted under the Tunisian-Italian cooperation project DE.DU.ENER.T, using renewable energy and economic criteria. The aim of the study is to improve the energy efficiency in order to minimize the electricity cost consumed in the laboratory. A Hybrid Renewable Energy System consisting of a photovoltaic field of 12KWc was installed to reduce the exorbitant bills, due to intensive energy equipment such as drying ovens and workstations, using sustainable, green and clean sources. In addition, a sizing theoretical study of the PV system was primarily realized in order to evaluate, in the first hand, the compatibility between different equipment and to compare, in the second hand, with results given by two software SMA Sunny Design and PV*SOL. We designed and managed these systems optimally to promote the self-consumption of the electric energy in the LPT Research laboratory building. The focus would be on the use of the PV system by evaluating the impacts of electricity generation using renewable energy levied on electricity grid (energy injection and extraction) and the economies that can be achieved during operating hours. Results of PV-SYST study obtained by the simulation of our installation will be discussed.

The issue of the optimal management of the available energy resources also at end-user level is getting more and more attention. The paper deals with the definition of innovative algorithms for managing electrical storage systems in hybrid photovoltaic and wind plants, also taking into account different pricing periods and a grid emergency condition in which the Utility can request an injection of power by the end-user. Application examples for explaining the operation of the algorithms are presented.

In this paper a wind electrical power generation system for Distributed on Site (DoS) applications is proposed. This system was developed and conceived in order to guarantee simple installation, use and service, obtaining a product that can be easily industrialized and put into the market with limited costs. The field of application of such an electrical generation system is addressed towards domestic or at the most toward condominium applications concerning moreover the opportunity of working in addition to combined photovoltaic and solar-thermal systems to enhance the renewable energy generation at house level (DoS). The proposed system has its hot spot in the blades shape, in the wind flux canalization system and in the permanent magnet synchronous generator (PMSG) optimized for this specific purpose. In fact with the proposed system intends to search the best aerodynamic profile and electrical generator to ensure the slightest encumbrance and the lowest weight. For this purpose the traditional and classical tangential wind turbine design, equipped with large blades, is overturned in favour of the use of numerous little blades. A further peculiarity of the system is the expected increase of its efficiency thanks to the presence of the wind flux channelling system with the elimination of the part opposing the wind and thanks to the adoption of a specifically designed PMSG.

The paper presents a prototype of a microsystem for the integration and the optimal management of renewable energy sources in order to attain a reduction of the total energy consumption of a not residential building. The system composed by the building and the prototype is an energy sustainable microsystem and is located in Italy in the city of Valderice. The microsystem has been conceived in the ENPI (European Neighborhood and Partnership Instrument) cross-border cooperation Italy - Tunisia 2007-2013 DE.DU.ENER.T. (Le DEveloppement DUrable dans la production ENERgetique dans le Territoire) research project framework. In the paper the purposes of the DE.DU.ENER.T. project are presented and the prototype is shown. Moreover a monitoring protocol for the evaluation of the energy and money savings is described.

In the present paper, a new approach to the management of energy resources in a research laboratory is proposed and evaluated by a simulation for the PV installation realized for the Tunisian-Italian cooperation project DE.DU.ENER.T, using renewable energy and economic criteria. The aim of this project is to improve energy efficiency order to minimize the electricity cost consumed at the laboratory, because according to the bills of electricity received we noticed that there is a high consumption of electrical current, from the STEG grid, and especially by the energy intensive equipment such as drying ovens and all the workstations. So we targeted to install a photovoltaic field of 12KWc to reduce these bills by using other sustainable, green and clean sources. In addition, a theoretical study of the PV system sizing realized manually in order to know in the first hand the compatibility between the different equipment of this installation and to compare the results with those found by the SMA Sunny Design software in the second hand. Then, we present the different result obtained by the simulation of our installation using a PV∗SOL simulation software. We designed and managed these systems optimally to promote the self-consumption of the electric energy in the building of LPT Research laboratory. We will focus on the use of the PV system by evaluating the impacts of electricity generation using renewable energy levied on electricity grid (energy injection and extraction) and the economies that can be achieved during the hours Operating.

The paper focuses on an energy sustainable prototype micro-system installed upon a roof of a building in Valderice (Italy). This micro-system has been conceived in the ENPI (European Neighborhood and Partnership Instrument) cross-border cooperation Italy - Tunisia 2007–2013 DE.DU.ENER.T. (Le DEveloppement DUrable dans la production ENERgetique dans le Territoire) research project framework. The main aim of this project is the construction of a sustainable energy micro-system prototype suitable for the optimal integration and management of renewable energy resources (photovoltaic, wind and solar thermal) and to reduce the building's energy consumption. In the paper the project and the prototype installed in Valderice (Italy) are described.

This paper analyzes how the electrical characteristics of a CIGS photovoltaic module are affected by the chemical composition and by the thickness variations of the CIGS absorber. The electrical characteristics here considered are the short circuit current, the open circuit voltage, the efficiency and the power peak. The chemical composition is varied by tuning the ratio between gallium and indium. This analysis has been performed by means of the wxAMPS software, developed by the University of Illinois. The above variations have been taken into account on a PV module made of 72 cells. This analysis has been carried out employing a PV module mathematical model developed and implemented by the Authors in Matlab environment.

An efficient strategy to improve unequally irradiated PV plants performances is based on the reconfiguration of the connections between the modules. In this paper, an algorithm, for this purpose conceived, is presented. Moreover, the design, realization and finally also the set up of a new reconfiguration system device is fully shown and discussed. The algorithm conceived simulates several possible series-parallel connections under varying irradiation conditions, and determines the optimal modules connection in order to get the maximum output power. In this way, the reconfiguration system may set up the reconfiguration strategy. The reconfiguration system prototype set up, basically consists of one acquisition and conditioning system, one control system (Arduino Mega 2560 based on the ATmega2560 microcontroller) and one actuation system. It has been conceived to research the best homogeneity condition (string PV modules irradiation condition) in order to increase the energy produced under partial shading conditions. © 2014 IEEE.

Global warming and energy demand are nowadays becoming one of the major issues of the third millennium, mainly because human activities seem to have a clear impact on the raise of CO2 emissions as never it has been experienced in the past. Among the different factors affecting CO2 emissions, energy demand from buildings constitutes one of the most important actors. Energy Management (EM) actions can reduce the energy consumption of the system and minimize peaks-level, by using a distributed control over every house. These local actions can greatly contribute to reduce the impact on the global CO2 emissions. An evaluation of the potential energy saving and CO2 emissions reduction on buildings and neighbours has been carried out, when a renewable energy system is locally installed. The exploitation of a combined solar and photovoltaic system and the integration of suitable energy management actions were deeply investigated. Savings up to 10% on grid losses in the Medium-Voltage (MV) and Low-Voltage (LV) electrical system is obtainable. A wide-spread application of EM (Energy Management) in houses and buildings could permit benefits for the transmission system and a considerable reduction of CO2 emission. The results here pointed out suggest the possibility of postponing the development and strengthening of electrical system. The consequent economic relevant benefit could persuade economic lobbies about the importance of EM through connected household appliances. In the paper a grid simulator has been defined with the specific inputs and parameters for modelling the distribution system, both for MV and LV. Results at neighbour and country level are very suitable and verify the relevant role of the CPS (Combined Photovoltaic Solar system) in the whole electric grid.

This paper introduces a versatile and reliable photovoltaic systems simulator. It includes the main components of a photovoltaic plant: a PV string and a PWM controlled boost chooper. The key feature of this simulator is the ability to consider different and non-uniform irradiation and temperature conditions (partial shading and partial heating of the strings). All the different I-V and P-V or P-I characteristics can then be determined in such non-uniform irradiation and temperature conditions, with the aim to try different MPPT algorithms. The simulator also allows to verify an enhanced version of the Incremental Conductance algorithm (IncCond) where, in order to reach the real absolute maximum power condition, the reference control current of the boost chopper are periodically reset to a given percentage of the short circuit current at standard conditions. After this perturbation, the steady state power values are registered and compared to establish the final value of reference current that allows the IncCond algorithm to reach a steady state at the real abolute maximum power transfer. © 2013 IEEE.

This work presents our preliminary results regarding an electrochemical process which allows the growth of nanostructured materials by means of nanopore templates. Also we analyze possible applications of this process to fabricate nanostructured semiconductors, such as CIGS, suitable for photovoltaic devices, and we consider the implications from the perspective of characterization techniques and device modelling when using such a technology.

A systematic evaluation of the potential energy saving and CO2 emissions reduction on buildings was carried out, when a renewable energy system is locally installed. The exploitation of a combined solar and photovoltaic system and the integration of suitable energy management actions were deeply investigated. A model of these solar and photovoltaic components has been developed and included within a complete house simulator, capable to precisely figure out the daily electric energy consumptions of typical apartments and to measure the positive actions induced by the added renewable energy. Saving up to 40% on the energy consumptions and even more savings on wiring losses seems to be easily obtainable.

Among the electrical energy production systems from renewable sources, the photovoltaic one represents today one of the most efficient and technically tested choice. In this paper the authors present a mathematical model that allows the maximization of the generated power of photovoltaic (PV) plants under unequally radiation conditions. In particular, thanks to the model of a PV plant, unequally radiated, developed in Matlab-Simulink environment, in this paper the mismatch problem of PV plants is dealt with. The simulations curried out allow to assert that by putting into action re-configuration techniques of series-parallel connections of PV plants, under unequally radiation, can allow to optimize the electrical energy production from these plants. This result opens scenarios of conceivable modifications to the PV field configurations today chosen during the design stage and unchangeable during the operating stage.

In order to succeed in observing the international agreements undertaken in the Kyoto agreement protocol, today it is necessary to increase the electrical energy production from renewables energy resources (RERs). In this paper a complete description of the Italian incentive systems for the production of electrical energy from photovoltaic (PV) and other RERs is done. Moreover, some considerations about the effects of the incentive actions on the wide spread of RERs to produce electrical energy are reported; particular attention is paid in the economical analysis related to PY and wind systems.

In this paper the design, realization and testing of a photovoltaic charging system suitable for the management of an electrically power assisted tricycle are described. This vehicle uses a photovoltaic module as a source of electric energy for the battery recharging. In this work, an overview on the needs of sustainable mobility and on the commercial electrically power assisted velocipedes is presented. The electrical rickshaw prototype, developed in the SDELab laboratory of the University of Palermo, is presented in detail, underlining the design, implementation and developing phases of the photovoltaic charging system assembled on the velocipede. Moreover, tests oriented on the setting up of the whole system and validation tests on the prototype are described, with the aim of determining the growing up of performances. Particular attention is dedicated to the vehicle autonomy, by using the management system here proposed. The results show how is possible to reach an increase of the 30% of the electrical rickshaw autonomy by using the management system conceived by the Authors. Furthermore, these tests are carried out in order to demonstrate that the electrical rickshaw vehicle supported by the PV charging system could be targeted for touristic purposes. © 2013 AEIT.