WorldWideScience

Sample records for stand-alone pv systems

  1. Models for a stand-alone PV system

    DEFF Research Database (Denmark)

    Hansen, A.D.; Sørensen, Poul Ejnar; Hansen, L.H.

    2001-01-01

    This report presents a number of models for modelling and simulation of a stand-alone photovoltaic (PV) system with a battery bank verified against a system installed at Risø National Laboratory. The work has been supported by the Danish Ministry ofEnergy, as a part of the activities in the Solar...... Energy Centre Denmark. The study is carried out at Risø National Laboratory with the main purpose to establish a library of simple mathematical models for each individual element of a stand-alone PVsystem, namely solar cells, battery, controller, inverter and load. The models for PV module and battery...

  2. Integrated Three-Port DC-DC Converter for Photovoltaic (PV) Battery Stand-alone Systems

    DEFF Research Database (Denmark)

    Ouyang, Ziwei; Andersen, Michael A. E.

    2016-01-01

    Several power sources such as PV solar arrays and battery are often used to manage the power flow for a photovoltaic (PV) based stand-alone power system due to the fluctuation nature of solar energy resource, and deliver a continuous power to the users in an appropriate form. Traditionally, three...... for PV and battery stand-alone system....

  3. Photovoltaic Module Simulink Model for a Stand-alone PV System

    Science.gov (United States)

    Qi, Chen; Ming, Zhu

    Photovoltaic(PV) Module is indispensable of a stand-alone PV system. In this paper, a one-diode equivalent circuit-based versatile simulation model in the form of masked block PV module is proposed. By the model, it is allowed to estimate behavior of PV module with respect changes on irradiance intensity, ambient temperature and parameters of the PV module. In addition, the model is capable of function of Maximum Power Point Tracking (MPPT) which can be used in the dynamic simulation of stand-alone PV systems.

  4. A Current Sensorless MPPT Control Method for a Stand-Alone-Type PV Generation System

    Science.gov (United States)

    Itako, Kazutaka; Mori, Takeaki

    In this paper, a current sensorless MPPT control method for a stand-alone-type PV generation system is proposed. This control method offers advantages of the simplified hardware configuration and the low cost, by using only one sensor to measure the PV output voltage. In the application to stand-alone-type with a battery load, the experimental results show that the estimated values of PV output current are accurate, and the use of the proposed MPPT control increases the PV generated energy by 16.3% compared to the conventional system. Furthermore, it is clarified that the proposed method has extremely high UUF (Useful utilization factor) of 98.7%.

  5. Design and Operation Studies of A Stand-Alone PV Generation System

    DEFF Research Database (Denmark)

    Hu, Yanting; Chen, Zhe; Zhang, Donglai

    2013-01-01

    This paper discusses the modeling, design and operation of a PV powered stand-alone system, which includes a PV array, a battery bank, power electronic converters and the associated control system. The design considerations are analyzed and a design platform is presented. Furthermore the operatio...

  6. Integrated Three-Port DC-DC Converter for Photovoltaic (PV) Battery Stand-alone Systems

    DEFF Research Database (Denmark)

    Ouyang, Ziwei; Andersen, Michael A. E.

    2016-01-01

    Several power sources such as PV solar arrays and battery are often used to manage the power flow for a photovoltaic (PV) based stand-alone power system due to the fluctuation nature of solar energy resource, and deliver a continuous power to the users in an appropriate form. Traditionally, three...

  7. A Control Method for Maximum Power Point Tracking in Stand-Alone-Type PV Generation Systems

    Science.gov (United States)

    Itako, Kazutaka; Mori, Takeaki

    In this paper, a new control method for maximum power point tracking (MPPT) in stand-alone-type PV generaton systems is proposed. In this control method, the operations detecting the maximum power point and tracking its point are alternately carried out by using a step-up DC—DC converter. This method requires neither the measurement of temperature and insolation level nor PV array model. In a stand-alone-type application with a battery load, the design method for the boost inductance L of the step-up DC—DC converter is described, and the experimental results show that the use of the proposed MPPT control increases the PV generated energy by 14.8% compared to the conventional system.

  8. Simulation of stand alone PV system; Dokuritsugata taiyoko hatsuden system no simulation

    Energy Technology Data Exchange (ETDEWEB)

    Kondo, H.; Ogawa, H.; Sekii, Y. [Chiba Institute of Technology, Chiba (Japan); Tsuda, I.; Nozaki, K. [Electrotechnical Laboratory, Tsukuba (Japan); Kurokawa, K. [Tokyo University of Agriculture and Technology, Tokyo (Japan)

    1996-10-27

    In order to evaluate the simulation results of a photovoltaic power generation system, an operation simulation was carried out using the actual measured data of a stand alone PV system in Miyakojima, Okinawa Prefecture, so as to make a comparison with the actual operation data. The electric power was supplied to 250 houses and primary/junior high schools in the surrounding villages, which had an average demand load of approximately 90kw and the maximum of approximately 200kw. The power was supplied through the PV power generation in the duration of the sunshine, with an excess power charged in storage batteries and then supplied from the batteries at night. The array capacity was made 750kWp, the output current and storage batteries being characteristic type with an actual efficiency curve used for the inverter. The weather data used were the actual inclined insolation quantity and the outside air temperature data for a period of one month of November. The power charged in excess of 100% in the batteries was termed as an overflow power. With the charging condition 30% or less, a diesel generator was run for a rated operation for one hour, the power of which was termed as a backup power. As a result, the simulation was found nearly in agreement with the actual measurements. 5 refs., 7 figs., 2 tabs.

  9. Use of Super-Capacitor to Enhance Charging Performance of Stand-Alone Solar PV System

    KAUST Repository

    Huang, B. J.

    2011-01-01

    Introduction: The battery charging performance in a stand-alone solar PV system affects the PV system efficiency and the load operating time. The New Energy Center of National Taiwan University has been devoted to the development of a PWM charging technique to continue charging the lead-acid battery after the overcharge point to increase the battery storage capacity by more than 10%. The present study intends to use the super-capacitor to further increase the charge capacity before the overcharge point of the battery. The super-capacitor is connected in parallel to the lead-acid battery. This will reduce the overall charging impedance during the charge and increase the charging current, especially in sunny weather. A system dynamics model of the lead-acid battery and super-capacitor was derived and the control system simulation was carried out to predict the charging performance for various weathers. It shows that the overall battery impedance decreases and charging power increases with increasing solar radiation. An outdoor comparative test for two identical PV systems with and without supercapacitor was carried out. The use of super-capacitor is shown to be able to increase the lead-acid charging capacity by more than 25% at sunny weather and 10% in cloudy weather. © Springer-Verlag Berlin Heidelberg 2011.

  10. Approaches for developing a sizing method for stand-alone PV systems with variable demand

    Energy Technology Data Exchange (ETDEWEB)

    Posadillo, R. [Grupo de Investigacion en Energias y Recursos Renovables, Dpto. de Fisica Aplicada, E.P.S., Universidad de Cordoba, Avda. Menendez Pidal s/n, 14004 Cordoba (Spain); Lopez Luque, R. [Grupo de Investigacion de Fisica para las Energias y Recursos Renovables, Dpto. de Fisica Aplicada. Edificio C2 Campus de Rabanales, 14071 Cordoba (Spain)

    2008-05-15

    Accurate sizing is one of the most important aspects to take into consideration when designing a stand-alone photovoltaic system (SAPV). Various methods, which differ in terms of their simplicity or reliability, have been developed for this purpose. Analytical methods, which seek functional relationships between variables of interest to the sizing problem, are one of these approaches. A series of rational considerations are presented in this paper with the aim of shedding light upon the basic principles and results of various sizing methods proposed by different authors. These considerations set the basis for a new analytical method that has been designed for systems with variable monthly energy demands. Following previous approaches, the method proposed is based on the concept of loss of load probability (LLP) - a parameter that is used to characterize system design. The method includes information on the standard deviation of loss of load probability ({sigma}{sub LLP}) and on two new parameters: annual number of system failures (f) and standard deviation of annual number of failures ({sigma}{sub f}). The method proves useful for sizing a PV system in a reliable manner and serves to explain the discrepancies found in the research on systems with LLP<10{sup -2}. We demonstrate that reliability depends not only on the sizing variables and on the distribution function of solar radiation, but on the minimum value as well, which in a given location and with a monthly average clearness index, achieves total solar radiation on the receiver surface. (author)

  11. Optimization of a stand-alone Solar PV-Wind-DG Hybrid System for Distributed Power Generation at Sagar Island

    Science.gov (United States)

    Roy, P. C.; Majumder, A.; Chakraborty, N.

    2010-10-01

    An estimation of a stand-alone solar PV and wind hybrid system for distributed power generation has been made based on the resources available at Sagar island, a remote area distant to grid operation. Optimization and sensitivity analysis has been made to evaluate the feasibility and size of the power generation unit. A comparison of the different modes of hybrid system has been studied. It has been estimated that Solar PV-Wind-DG hybrid system provides lesser per unit electricity cost. Capital investment is observed to be lesser when the system run with Wind-DG compared to Solar PV-DG.

  12. Simulation of stand alone PV systems; Dokuritsugata taiyoko hatsuden system no simulation

    Energy Technology Data Exchange (ETDEWEB)

    Tsuda, I.; Sakuta, K. [Electrotechnical Laboratory, Tsukuba (Japan); Oshiro, T. [Japan Quality Assurance Organization, Tokyo (Japan); Kurokawa, K. [Tokyo University of Agriculture and Technology, Tokyo (Japan)

    1997-11-25

    Studies are performed to develop a simulation program for a stand-alone photovoltaic power generation system equipped with a lead acid battery. In this stand-alone photovoltaic power generation system, the load is connected in shunt with the solar cell array output through the intermediary of a lead acid battery and inverter. The program is a model in which the solar cell model is built taking parallel resistance into account, and the temperature-dependence of the constants is described using approximations experimentally obtained by Solar Techno Center of JQA (Japan Quality Assurance Organization), Hamamatsu. Insolation data for the model is described using METPV compiled by Japan Weather Association, and load data is described using data actually measured at Shizuoka. This program is compared with the data of operation at Hamamatsu, and the result is almost satisfactory. Simulations are conducted at five typical locations in Japan using this program, and it is found that the array load matching correction factor is dependent on seasonal changes rather than locality, that the battery contribution rate does not change much throughout the year, and that it is not dependent on locality. 5 refs., 7 figs., 3 tabs.

  13. Solar pv fed stand-alone excitation system of a synchronous machine for reactive power generation

    Science.gov (United States)

    Sudhakar, N.; Jain, Siddhartha; Jyotheeswara Reddy, K.

    2017-11-01

    This paper presents a model of a stand-alone solar energy conversion system based on synchronous machine working as a synchronous condenser in overexcited state. The proposed model consists of a Synchronous Condenser, a DC/DC boost converter whose output is fed to the field of the SC. The boost converter is supplied by the modelled solar panel and a day time variable irradiance is fed to the panel during the simulation time. The model also has one alternate source of rechargeable batteries for the time when irradiance falls below a threshold value. Also the excess power produced when there is ample irradiance is divided in two parts and one is fed to the boost converter while other is utilized to recharge the batteries. A simulation is done in MATLAB-SIMULINK and the obtained results show the utility of such modelling for supplying reactive power is feasible.

  14. Hydrogen-based energy storage unit for stand alone PV systems

    International Nuclear Information System (INIS)

    Labbe, J.

    2006-12-01

    Stand alone systems supplied only by a photovoltaic generator need an energy storage unit to be fully self sufficient. Lead acid batteries are commonly used to store energy because of their low cost, despite several operational constraints. A hydrogen-based energy storage unit (HESU) could be another candidate, including an electrolyser, a fuel cell and a hydrogen tank. However many efforts still need to be carried out for this technology to reach an industrial stage. In particular, market outlets must be clearly identified. The study of small stationary applications (few kW) is performed by numerical simulations. A simulator is developed in the Matlab/Simulink environment. It is mainly composed of a photovoltaic field and a storage unit (lead acid batteries, HESU, or hybrid storage HESU/batteries). The system component sizing is achieved in order to ensure the complete system autonomy over a whole year of operation. The simulator is tested with 160 load profiles (1 kW as a yearly mean value) and three locations (Algeria, France and Norway). Two coefficients are set in order to quantify the correlation between the power consumption of the end user and the renewable resource availability at both daily and yearly scales. Among the tested cases, a limit value of the yearly correlation coefficient came out, enabling to recommend the use of the most adapted storage to a considered case. There are cases for which using HESU instead of lead acid batteries can increase the system efficiency, decrease the size of the photovoltaic field and improve the exploitation of the renewable resource. In addition, hybridization of HESU with batteries always leads to system enhancements regarding its sizing and performance, with an efficiency increase by 10 to 40 % depending on the considered location. The good agreement between the simulation data and field data gathered on real systems enabled the validation of the models used in this study. (author)

  15. PV LED ENGINE characterization lab for stand alone light-to-light systems

    DEFF Research Database (Denmark)

    Poulsen, Peter Behrensdorff; Thorsteinsson, Sune; Lindén, Johannes

    2015-01-01

    PV-powered lighting systems, light-to-light systems (L2L), offer outdoor lighting where it is elsewhere cumbersome to enable lighting. Application of these systems at high latitudes, where the difference in day length between summer and winter is large and the solar energy is low requires smart...... dimming functions for reliable lighting. A barrier for exploiting use of standalone solar lighting for the urban environment seem to be lack of knowledge and lack of available tools for proper dimensioning. In this work the development of powerful dimensioning tool is described and initial measurements...

  16. A high-performance stand-alone solar PV power system for LED lighting

    KAUST Repository

    Huang, B. J.

    2010-06-01

    The present study developed a high-performance solar PV power technology for the LED lighting of a solar home system. The nMPPO (near-Maximum-Power- Point- Operation) design is employed in system design to eliminate MPPT. A feedback control system using pulse width modulation (PWM) technique was developed for battery charging control which can increase the charging capacity by 78%. For high-efficiency lighting, the LED is directly driven by battery using a PWM discharge control to eliminate a DC/DC converter. Two solar-powered LED lighting systems (50W and 100W LED) were built. The long-term outdoor tests have shown that the loss of load probability for full-night lighting requirement is zero for 50W LED and 3.6% for 100W LED. © 2010 IEEE.

  17. ANFIS-based estimation of PV module equivalent parameters: application to a stand-alone PV system with MPPT controller

    OpenAIRE

    KULAKSIZ, Ahmet Afşin

    2012-01-01

    The performance and system cost of photovoltaic (PV) systems can be improved by employing high-efficiency power conditioners with maximum power point tracking (MPPT) methods. Fast implementation and accurate operation of MPPT controllers can be realized by modeling the characteristics of PV modules, obtaining equivalent parameters. In this study, adaptive neuro-fuzzy inference systems (ANFISs) have been used to obtain 3 of the parameters in a single-diode model of PV cells, namely serie...

  18. Comparison of Turkey’s Geographical Regions in terms of Stand-Alone PV System Design and Cost Parameters

    Directory of Open Access Journals (Sweden)

    Nevzat Onat

    2017-01-01

    Full Text Available Stand-alone photovoltaic (SAPV systems are widely used in rural areas where there is no national grid or as a precaution against power outages. In this study, technical and economic analysis of a SAPV system was carried out using meteorological data for 75 province centers in seven geographical regions of Turkey. Obtained results for each province center were separated by geographical area. The averages of the centers for each region are taken as output. A calculation algorithm based on MsExcel has been established for these operations. The analyses made with the developed algorithm are repeated for five different scenarios that they cover periods of time when a constant strong load is active for all seasons (winter, spring, summer, and autumn and all year round. The developed algorithm calculates the life-cycle cost, the unit energy cost, the electrical capacity utilization rate, the amount of generated/excess energy per month, the initial investment/replacement, and operating and maintenance (O&M costs of each element. As a result, geographical regions of Turkey are compared in terms of these outputs graphically. Further investigations may include the sale of excess energy generated, small-scale PV system cost factors parallel to the grid, and the effects of government incentives.

  19. An efficient sizing method for a stand-alone PV system in terms of the observed block extremes

    International Nuclear Information System (INIS)

    Chen, Shin-Guang

    2012-01-01

    Highlights: ► A fast optimal sizing method under climate change. ► It provides the method of creating climate cycles for PV system applications. ► It proposes a new reliability indicator to denote the upper bound probability of a PV application. ► It presents a premiere economic optimization for such approach. ► It gives examples to illustrate the proposed approach. -- Abstract: This paper proposes a novel and fast sizing method under the constant daily load profile for sizing a stand-alone PV system. The term “efficient sizing” means that the approach did not use simulation but could get the result as good as those employing simulation. So, the sizing method is more efficient than the others. Traditionally, a typical day or a typical year’s solar irradiation profile is employed for the sizing task. However, facing the global warming crisis as well as the fact that no 2 years would have the same weather condition for a single site, this approach statistically models the trend of climate change year by year and put it into the sizing formula, so that the results are optimal for the current weather condition and for the future as well. Hence, the suitable size for the PV array and the number of batteries are obtained by purely computation. This is different from the traditional sizing curve method. Although the traditional sizing curve method were satisfactory in the normal cases, they might fail in the extreme climate condition. This paper concludes the behavior of the extreme climate for at least 20 years. So, the derived system may have statistical confidence for at least 20 years of operation. A new reliability index (Loss of Power Probability) in terms of Extreme Value Theory is introduced. LPP provides upper bound reliability for application and rich information for many extreme events. A technological and economical comparison among the traditional daily energy balance method, sizing curve method and this approach is conducted and shows the

  20. Ampere hour method of sizing a stand alone photovoltaic system ...

    African Journals Online (AJOL)

    Stand-alone photovoltaic power systems are natural options for application in electrification of remote areas which are not served by the grid electricity supply system. An ampere-hour method of sizing a stand-alone PV system for application in any remote location has been presented. The design which is for both ac and dc ...

  1. A compact seven switches topology and reduced DC-link capacitor size for single-phase stand-alone PV system with hybrid energy storages

    DEFF Research Database (Denmark)

    Liu, Xiong; Wang, Peng; Loh, Poh Chiang

    2011-01-01

    Single-phase stand-alone PV system is suitable for household applications in remote area. Hybrid battery/ultra-capacitor energy storage can reduce charge and discharge cycles and avoid deep discharges of battery. This paper proposes a compact seven switches structure for stand-alone PV system......-order harmonic current caused by single-phase inverter. In the proposed compact topology, a small size DC-link capacitor can achieve the same function through charging/discharging control of ultra-capacitor to mitigate second-order ripple current. Simulation results are provided to validate the effectiveness......, which otherwise needs nine switches configuration, inclusive of one switch for boost converter, four switches for single-phase inverter and four switches for two DC/DC converters of battery and ultra-capacitor. It is well-known that a bulky DC-link capacitor is always required to absorb second...

  2. System dynamic model and charging control of lead-acid battery for stand-alone solar PV system

    KAUST Repository

    Huang, B.J.

    2010-05-01

    The lead-acid battery which is widely used in stand-alone solar system is easily damaged by a poor charging control which causes overcharging. The battery charging control is thus usually designed to stop charging after the overcharge point. This will reduce the storage energy capacity and reduce the service time in electricity supply. The design of charging control system however requires a good understanding of the system dynamic behaviour of the battery first. In the present study, a first-order system dynamics model of lead-acid battery at different operating points near the overcharge voltage was derived experimentally, from which a charging control system based on PI algorithm was developed using PWM charging technique. The feedback control system for battery charging after the overcharge point (14 V) was designed to compromise between the set-point response and the disturbance rejection. The experimental results show that the control system can suppress the battery voltage overshoot within 0.1 V when the solar irradiation is suddenly changed from 337 to 843 W/m2. A long-term outdoor test for a solar LED lighting system shows that the battery voltage never exceeded 14.1 V for the set point 14 V and the control system can prevent the battery from overcharging. The test result also indicates that the control system is able to increase the charged energy by 78%, as compared to the case that the charging stops after the overcharge point (14 V). © 2010 Elsevier Ltd. All rights reserved.

  3. A GUI Based Software for Sizing Stand Alone AC Coupled Hybrid PV-Diesel Power System under Malaysia Climate

    Science.gov (United States)

    Syafiqah Syahirah Mohamed, Nor; Amalina Banu Mohamat Adek, Noor; Hamid, Nurul Farhana Abd

    2018-03-01

    This paper presents the development of Graphical User Interface (GUI) software for sizing main component in AC coupled photovoltaic (PV) hybrid power system based on Malaysia climate. This software provides guideline for PV system integrator to design effectively the size of components and system configuration to match the system and load requirement with geographical condition. The concept of the proposed software is balancing the annual average renewable energy generation and load demand. In this study, the PV to diesel generator (DG) ratio is introduced by considering the hybrid system energy contribution. The GUI software is able to size the main components in the PV hybrid system to meet with the set target of energy contribution ratio. The rated powers of the components to be defined are PV array, grid-tie inverter, bi-directional inverter, battery storage and DG. GUI is used to perform all the system sizing procedures to make it user friendly interface as a sizing tool for AC coupled PV hybrid system. The GUI will be done by using Visual Studio 2015 based on the real data under Malaysia Climate.

  4. A control strategy for PV stand-alone applications

    Science.gov (United States)

    Slouma, S.; Baccar, H.

    2015-04-01

    This paper proposes a stand-alone photovoltaic (PV) system study in domestic applications. Because of the decrease in power of photovoltaic module as a consequence of changes in solar radiation and temperature which affect the photovoltaic module performance, the design and control of DC-DC buck converter was proposed for providing power to the load from a photovoltaic source.In fact, the control of this converter is carried out with integrated MPPT (Maximum Power Point Tracking) algorithm which ensures a maximum energy generated by the PV arrays. Moreover, the output stage is composed by a battery energy storage system, dc-ac inverter, LCL filter which enables higher efficiency, low distortion ac waveforms and low leakage currents. The control strategy adopted is cascade control composed by two regulation loops.Simulations performed with PSIM software were able to validate the control system.The realization and testing of the photovoltaic system were achieved in the Photovoltaic laboratory of the Centre for Research and Energy Technologies at the Technopark Borj Cedria. Experimental results verify the effeciency of the proposed system.

  5. A practical multi-objective design approach for optimum exhaust heat recovery from hybrid stand-alone PV-diesel power systems

    International Nuclear Information System (INIS)

    Yousefi, Moslem; Kim, Joong Hoon; Hooshyar, Danial; Yousefi, Milad; Sahari, Khairul Salleh Mohamed; Ahmad, Rodina Binti

    2017-01-01

    Highlights: • Heat recovery exchanger is designed based on practical conditions of a hybrid power system. • Off-the-grid electricity system modeling and analysis using micro-grid analysis software HOMER. • NSGA-II is used for the multi-objective design optimization task. • A new local search is proposed to incorporate the engineering knowledge in NSGA-II. • The proposed approach outperforms the existing ones. - Abstract: Integration of solar power and diesel generators (DGs) together with battery storage has proven to be an efficient choice for stand-alone power systems (SAPS). For higher energy efficiency, heat recovery from exhaust gas of the DG can also be employed to supply all or a portion of the thermal energy demand. Although the design of such heat recovery systems (HRSs) has been studied, the effect of solar power integration has not been taken into account. In this paper, a new approach for practical design of these systems based on varying engine loads is presented. Fast and elitist non-dominated sorting genetic algorithm (NSGA-II) equipped with a novel local search was used for the design process, considering conflicting objectives of annual energy recovery and total cost of the system, and six design variables. An integrated power system, designed for a remote SAPS, was used to evaluate the design approach. The optimum power supply system was first designed using the commercial software Hybrid Optimization of Multiple Energy Resources (HOMER), based on power demand and global solar energy in the region. Heat recovery design was based on the outcome of HOMER for DG hourly load, considering different power scenarios. The proposed approach improves the annual heat recovery of the PV/DG/battery system by 4%, PV/battery by 1.7%, and stand-alone DG by 1.8% when compared with a conventional design based on nominal DG load. The results prove that the proposed approach is effective and that load calculations should be taken into account prior to

  6. Performance evaluation of stand alone hybrid PV-wind generator

    Energy Technology Data Exchange (ETDEWEB)

    Nasir, M. N. M.; Saharuddin, N. Z.; Sulaima, M. F.; Jali, Mohd Hafiz; Bukhari, W. M.; Bohari, Z. H. [Faculty of Electrical Engineering, Universiti Teknikal Malaysia Melaka (UTeM), Hang Tuah Jaya, 76100 Melaka (Malaysia); Yahaya, M. S. [Faculty of Engineering Technology, Universiti Teknikal Malaysia Melaka (UTeM), Hang Tuah Jaya, 76100 Melaka (Malaysia)

    2015-05-15

    This paper presents the performance evaluation of standalone hybrid system on Photovoltaic (PV)-Wind generator at Faculty of Electrical Engineering (FKE), UTeM. The hybrid PV-Wind in UTeM system is combining wind turbine system with the solar system and the energy capacity of this hybrid system can generate up to charge the battery and supply the LED street lighting load. The purpose of this project is to evaluate the performance of PV-Wind hybrid generator. Solar radiation meter has been used to measure the solar radiation and anemometer has been used to measure the wind speed. The effectiveness of the PV-Wind system is based on the various data that has been collected and compared between them. The result shows that hybrid system has greater reliability. Based on the solar result, the correlation coefficient shows strong relationship between the two variables of radiation and current. The reading output current followed by fluctuate of solar radiation. However, the correlation coefficient is shows moderate relationship between the two variables of wind speed and voltage. Hence, the wind turbine system in FKE show does not operate consistently to produce energy source for this hybrid system compare to PV system. When the wind system does not fully operate due to inconsistent energy source, the other system which is PV will operate and supply the load for equilibrate the extra load demand.

  7. Performance evaluation of stand alone hybrid PV-wind generator

    Science.gov (United States)

    Nasir, M. N. M.; Saharuddin, N. Z.; Sulaima, M. F.; Jali, Mohd Hafiz; Bukhari, W. M.; Bohari, Z. H.; Yahaya, M. S.

    2015-05-01

    This paper presents the performance evaluation of standalone hybrid system on Photovoltaic (PV)-Wind generator at Faculty of Electrical Engineering (FKE), UTeM. The hybrid PV-Wind in UTeM system is combining wind turbine system with the solar system and the energy capacity of this hybrid system can generate up to charge the battery and supply the LED street lighting load. The purpose of this project is to evaluate the performance of PV-Wind hybrid generator. Solar radiation meter has been used to measure the solar radiation and anemometer has been used to measure the wind speed. The effectiveness of the PV-Wind system is based on the various data that has been collected and compared between them. The result shows that hybrid system has greater reliability. Based on the solar result, the correlation coefficient shows strong relationship between the two variables of radiation and current. The reading output current followed by fluctuate of solar radiation. However, the correlation coefficient is shows moderate relationship between the two variables of wind speed and voltage. Hence, the wind turbine system in FKE show does not operate consistently to produce energy source for this hybrid system compare to PV system. When the wind system does not fully operate due to inconsistent energy source, the other system which is PV will operate and supply the load for equilibrate the extra load demand.

  8. Performance evaluation of stand alone hybrid PV-wind generator

    International Nuclear Information System (INIS)

    Nasir, M. N. M.; Saharuddin, N. Z.; Sulaima, M. F.; Jali, Mohd Hafiz; Bukhari, W. M.; Bohari, Z. H.; Yahaya, M. S.

    2015-01-01

    This paper presents the performance evaluation of standalone hybrid system on Photovoltaic (PV)-Wind generator at Faculty of Electrical Engineering (FKE), UTeM. The hybrid PV-Wind in UTeM system is combining wind turbine system with the solar system and the energy capacity of this hybrid system can generate up to charge the battery and supply the LED street lighting load. The purpose of this project is to evaluate the performance of PV-Wind hybrid generator. Solar radiation meter has been used to measure the solar radiation and anemometer has been used to measure the wind speed. The effectiveness of the PV-Wind system is based on the various data that has been collected and compared between them. The result shows that hybrid system has greater reliability. Based on the solar result, the correlation coefficient shows strong relationship between the two variables of radiation and current. The reading output current followed by fluctuate of solar radiation. However, the correlation coefficient is shows moderate relationship between the two variables of wind speed and voltage. Hence, the wind turbine system in FKE show does not operate consistently to produce energy source for this hybrid system compare to PV system. When the wind system does not fully operate due to inconsistent energy source, the other system which is PV will operate and supply the load for equilibrate the extra load demand

  9. Method to size photovoltaic arrays for hydrogen-PV stand-alone power stations

    Energy Technology Data Exchange (ETDEWEB)

    Barra, L.; Coiante, D. [ENEA, Casaccia (Italy). Area Energetica

    1993-11-01

    With reference to a stand alone power plant configuration, a photovoltaic (PV) system, integrated with an electrolytic hydrogen production and fuel cell reconversion line, is examined with the aim of checking the possibility of assuring energy supply for a given load with time continuity. In order to size the PV array in function of the annual load diagram, for a given site, a method, which utilizes the monthly average values of sun energy density collected on horizontal surface as input data, is presented. The results demonstrate that a PV-H{sub 2} system is suitable for a modular stand alone solar power station, able to supply continuously each generic load. This technical acquisition has to be considered as the first necessary condition to get photovoltaics to overcome the limit due to working intermittence and become a real energy option. An example of an application for a small Mediterranean island, the Volcano Island, permanently inhabited by 469 people, is also discussed. This typical case can be actually show the technical viability of the PV-H{sub 2} solution in powering a small community with the required reliability.

  10. Hydrogen-based energy storage unit for stand alone PV systems; L'hydrogene electrolytique comme moyen de stockage d'electricite pour systemes photovoltaiques isoles

    Energy Technology Data Exchange (ETDEWEB)

    Labbe, J

    2006-12-15

    Stand alone systems supplied only by a photovoltaic generator need an energy storage unit to be fully self sufficient. Lead acid batteries are commonly used to store energy because of their low cost, despite several operational constraints. A hydrogen-based energy storage unit (HESU) could be another candidate, including an electrolyser, a fuel cell and a hydrogen tank. However many efforts still need to be carried out for this technology to reach an industrial stage. In particular, market outlets must be clearly identified. The study of small stationary applications (few kW) is performed by numerical simulations. A simulator is developed in the Matlab/Simulink environment. It is mainly composed of a photovoltaic field and a storage unit (lead acid batteries, HESU, or hybrid storage HESU/batteries). The system component sizing is achieved in order to ensure the complete system autonomy over a whole year of operation. The simulator is tested with 160 load profiles (1 kW as a yearly mean value) and three locations (Algeria, France and Norway). Two coefficients are set in order to quantify the correlation between the power consumption of the end user and the renewable resource availability at both daily and yearly scales. Among the tested cases, a limit value of the yearly correlation coefficient came out, enabling to recommend the use of the most adapted storage to a considered case. There are cases for which using HESU instead of lead acid batteries can increase the system efficiency, decrease the size of the photovoltaic field and improve the exploitation of the renewable resource. In addition, hybridization of HESU with batteries always leads to system enhancements regarding its sizing and performance, with an efficiency increase by 10 to 40 % depending on the considered location. The good agreement between the simulation data and field data gathered on real systems enabled the validation of the models used in this study. (author)

  11. A sizing method for stand-alone PV installations with variable demand

    Energy Technology Data Exchange (ETDEWEB)

    Posadillo, R. [Grupo de Investigacion en Energias y Recursos Renovables, Dpto. de Fisica Aplicada, E.P.S., Universidad de Cordoba, Avda. Menendez Pidal s/n, 14004 Cordoba (Spain); Lopez Luque, R. [Grupo de Investigacion de Fisica Para las Energias y Recursos Renovables, Dpto. de Fisica Aplicada, Edificio C2 Campus de Rabanales, 14071 Cordoba (Spain)

    2008-05-15

    The practical applicability of the considerations made in a previous paper to characterize energy balances in stand-alone photovoltaic systems (SAPV) is presented. Given that energy balances were characterized based on monthly estimations, the method is appropriate for sizing installations with variable monthly demands and variable monthly panel tilt (for seasonal estimations). The method presented is original in that it is the only method proposed for this type of demand. The method is based on the rational utilization of daily solar radiation distribution functions. When exact mathematical expressions are not available, approximate empirical expressions can be used. The more precise the statistical characterization of the solar radiation on the receiver module, the more precise the sizing method given that the characterization will solely depend on the distribution function of the daily global irradiation on the tilted surface H{sub g{beta}}{sub i}. This method, like previous ones, uses the concept of loss of load probability (LLP) as a parameter to characterize system design and includes information on the standard deviation of this parameter ({sigma}{sub LLP}) as well as two new parameters: annual number of system failures (f) and the standard deviation of annual number of system failures ({sigma}{sub f}). This paper therefore provides an analytical method for evaluating and sizing stand-alone PV systems with variable monthly demand and panel inclination. The sizing method has also been applied in a practical manner. (author)

  12. Deterrents on the Over Utilisation of Stand Alone Photovoltaic (PV ...

    African Journals Online (AJOL)

    At inception of the programme, systems were either undersized, or over utilised as clients did not reveal their usage needs in an attempt to reduce costs. This resulted in battery failures and other system breakdowns. The NPVREP categorised systems in order to alleviate the problem of under sizing and/or over utilization of ...

  13. Design of a Stand-Alone Photovoltaic (PV Models for Home Lightings and Clean Environment

    Directory of Open Access Journals (Sweden)

    Vincent Anayochukwu Ani

    2016-01-01

    Full Text Available This paper gives a well-documented health risks of fuel-based lighting (kerosene lamps and fuel-powered generators and proposed a design of a stand-alone solar PV system for sustainable home lightings in rural Nigerian area. The design was done in three different patterns of electricity consumptions with energy efficient lightings (EELs using two different battery types (Rolls Surrette 6CS25PS and hoppecke 10 OpzS 1000 on; i judicious power consumption, ii normal power consumption, iii excess power consumption; and compared them with the incandescent light bulb consumption. The stand-alone photovoltaic energy systems were designed to match the rural Nigerian sunlight and weather conditions to meet the required lightings of the household. The objective function and constraints for the design models were formulated and optimization procedure were used to demonstrate the best solution (reliability at the lowest lifecycle cost. Initial capital costs as well as annualized costs over 5, 10, 15, 20, and 25 years were quantified and documented. The design identified the most cost-effective and reliable solar and battery array among the patterns of electricity consumption with energy efficient lighting options (judicious power consumption, normal power consumption, and excess power consumption.

  14. Techno-economic analysis of stand alone solar pv systems for remote base stations in Ghana. (a case study at Abofrem vodafone cell site)

    International Nuclear Information System (INIS)

    Denkyira, Samuel

    2015-06-01

    Information and Communications Technologies (ICT) have become an important part of today’s global economy. ICT infrastructural development is developing at a very fast pace in Ghana. Growth is above the 1.1% average for Sub-Saharan Africa. The growth in the sector has meant a massive investment in telecommunication infrastructure such as base stations from telecom companies such as Vodafone, Millicom, Glo, Espresso, MTN etc. Hundreds of base stations have been installed all over the country. Currently base stations depend mainly on the national grid, with diesel generators as backups, for its power requirement. In some remote or hilly areas where there are no grid supplied electricity, base stations are usually powered with diesel fuelled generators since lengthy grid extensions may not be cost effective. In addition to high fuel delivery and consumption costs, maintenance of the generators can also be expensive in terms of parts and labour time working on the unit. There are also concerns about environmental pollution using diesel generators. Photovoltaic technology has the ability to convert solar energy into electricity consuming no fossil fuels, using no moving parts, creating no pollution and noise, and lasting for years with little maintenance. The environmental, noise, reliability and power availability benefits of the PV system make it an attractive option. Ghana, being a few degrees north of the equator, is endowed with enormous solar energy resource spread across the entire country. Daily solar radiation level ranges from 4 kWh/m 2 to 6 kWh/m 2 . The annual sunshine duration ranges between 1800 to 3000 hours offering very high potential for grid connected and off grid applications. In this thesis work, the use of solar PV technology as a cost effective source of power for cellular base stations in remote or hilly areas, far off the national grid, is reviewed. RETScreen software is used to determine the technical and financial viability of the PV system

  15. Stand Alone Battery Thermal Management System

    Energy Technology Data Exchange (ETDEWEB)

    Brodie, Brad [Denso International America, Incorporated, Southfield, MI (United States)

    2015-09-30

    The objective of this project is research, development and demonstration of innovative thermal management concepts that reduce the cell or battery weight, complexity (component count) and/or cost by at least 20%. The project addresses two issues that are common problems with current state of the art lithium ion battery packs used in vehicles; low power at cold temperatures and reduced battery life when exposed to high temperatures. Typically, battery packs are “oversized” to satisfy the two issues mentioned above. The first phase of the project was spent making a battery pack simulation model using AMEsim software. The battery pack used as a benchmark was from the Fiat 500EV. FCA and NREL provided vehicle data and cell data that allowed an accurate model to be created that matched the electrical and thermal characteristics of the actual battery pack. The second phase involved using the battery model from the first phase and evaluate different thermal management concepts. In the end, a gas injection heat pump system was chosen as the dedicated thermal system to both heat and cool the battery pack. Based on the simulation model. The heat pump system could use 50% less energy to heat the battery pack in -20°C ambient conditions, and by keeping the battery cooler at hot climates, the battery pack size could be reduced by 5% and still meet the warranty requirements. During the final phase, the actual battery pack and heat pump system were installed in a test bench at DENSO to validate the simulation results. Also during this phase, the system was moved to NREL where testing was also done to validate the results. In conclusion, the heat pump system can improve “fuel economy” (for electric vehicle) by 12% average in cold climates. Also, the battery pack size, or capacity, could be reduced 5%, or if pack size is kept constant, the pack life could be increased by two years. Finally, the total battery pack and thermal system cost could be reduced 5% only if the

  16. PMBLDCG based stand-alone wind energy conversion system for ...

    African Journals Online (AJOL)

    This paper deals with a permanent magnet brushless DC generator (PMBLDCG) based stand-alone wind energy conversion system (WECS) for small scale power generation. A buck-boost DC-DC converter is used for controlling the PMBLDCG speed to achieve optimum energy output from the wind turbine without sensing ...

  17. Future UK markets for stand-alone renewable energy systems

    International Nuclear Information System (INIS)

    Paish, O.

    1999-01-01

    A study to identify and quantify the market for stand-alone renewable energy supplies of power (photovoltaics, wind and micro-hydro electricity systems) was described. The study focused on small systems, generally less than a few kW installed capacity. It was suggested that in the UK, the emphasis on grid-connected renewable energy technologies (RETs) has blurred the fact that it is 'off-grid' renewable systems that can offer more immediate real commercial markets for the renewables business. With the likelihood of a significant increase in demand for renewables world wide over the next ten years, the UK needs to make a special effort to become involved

  18. A Simple Sizing Algorithm for Stand-Alone PV/Wind/Battery Hybrid Microgrids

    Directory of Open Access Journals (Sweden)

    Jing Li

    2012-12-01

    Full Text Available In this paper, we develop a simple algorithm to determine the required number of generating units of wind-turbine generator and photovoltaic array, and the associated storage capacity for stand-alone hybrid microgrid. The algorithm is based on the observation that the state of charge of battery should be periodically invariant. The optimal sizing of hybrid microgrid is given in the sense that the life cycle cost of system is minimized while the given load power demand can be satisfied without load rejection. We also report a case study to show the efficacy of the developed algorithm.

  19. Photovoltaic OLED Driver for Low-Power Stand-Alone Light-to-Light Systems

    DEFF Research Database (Denmark)

    Ploug, Rasmus Overgaard; Knott, Arnold

    2016-01-01

    Photovoltaic (PV) stand-alone systems need to achieve multiple energy conversion modes. I.e. the energy conversion from PV to a local energy storage as well as energy conversion from the energy storage to the load. This paper documents the practical design considerations for the development of a ...... conversion from photovoltaic panel to the battery, and 97 % in the area 1.4 W to 2 W for power delivery to the OLED.......Photovoltaic (PV) stand-alone systems need to achieve multiple energy conversion modes. I.e. the energy conversion from PV to a local energy storage as well as energy conversion from the energy storage to the load. This paper documents the practical design considerations for the development...... of a three-port-converter for this purpose optimized for the specifications for driving an Organic Light Emitting Diode (OLED) panel intended for lighting purposes. By using a three-port-converter, featuring shared components for each conversion mode, the converter reaches 97 % efficiency at 1.8 W during...

  20. Modeling, Design and Simulation of Stand-Alone Photovoltaic Power Systems with Battery Storage

    Directory of Open Access Journals (Sweden)

    Abd Essalam BADOUD

    2013-06-01

    Full Text Available Stand alone renewable energy based on photovoltaic systems accompanied with battery storage system are beginning to play an important role over the world to supply power to remote areas. The objective of the study reported in this paper is to elaborate and design a bond graphs model for sizing stand-alone domestic solar photovoltaic electricity systems and simulating the performance of the systems in a tropical climate. The systems modelled consist of an array of PV modules, a lead-acid battery, and a number of direct current appliances. This paper proposes the combination of lead acid battery system with a typical stand alone photovoltaic energy system under variable loads. The main activities of this work purpose to establish library graphical models for each individual component of standalone photovoltaic system. Control strategy has been considered to achieve permanent power supply to the load via photovoltaic/battery based on the power available from the sun. The complete model was simulated under two testing including sunny and cloudy conditions. Simulation of the system using Symbols software was performed and the results of simulation show the superior stable control system and high efficiency. These results have been contrasted with real measured data from a measurement campaign plant carried on electrical engineering laboratory of Grenoble using various interconnection schemes are presented.

  1. Solar Photovoltaic Applications Seminar: Design, installation and operation of small, stand-alone photovoltaic power systems

    Science.gov (United States)

    1980-07-01

    An introduction to photoconductivity, semiconductors, and solar photovoltaic cells is included along with a demonstration of specific applications and application identification. Small solar cell power system design engineering is discussed. Solar PV power system applications involve classical direct electrical energy conversion and electric power system analysis and synthesis. Presentations and examples involve a variety of disciplines including structural analysis, electric power and load analysis, reliability, sizing and optimization; and, installation, operation and maintenance. Four specific system designs are demonstrated: water pumping; domestic uses; navigational and aircraft aids; and telecommunications. All of the applications discussed are for small power requirement (under 2 kilowatts), stand alone systems to be used in remote locations.

  2. Analyzing grid extension and stand-alone photovoltaic systems for the cost-effective electrification of Kenya

    NARCIS (Netherlands)

    Zeyringer, Marianne; Pachauri, Shonali; Schmid, Erwin; Schmidt, Johannes; Worrell, Ernst; Morawetz, Ulrich B.

    2015-01-01

    The declaration of 2014-2024 as the Decade of Sustainable Energy for All has catalyzed actions towards achieving universal electricity access. The high costs of building electric infrastructure are a major impediment to improved access, making stand-alone photovoltaic (PV) systems an attractive

  3. Optimum autonomous stand-alone photovoltaic system design on the basis of energy pay-back analysis

    International Nuclear Information System (INIS)

    Kaldellis, J.K.; Zafirakis, D.; Kondili, E.

    2009-01-01

    Stand-alone photovoltaic (PV) systems comprise one of the most promising electrification solutions for covering the demand of remote consumers. However, such systems are strongly questioned due to extreme life-cycle (LC) energy requirements. For similar installations to be considered as environmentally sustainable, their LC energy content must be compensated by the respective useful energy production, i.e. their energy pay-back period (EPBP) should be found less than their service period. In this context, an optimum sizing methodology is currently developed, based on the criterion of minimum embodied energy. Various energy autonomous stand-alone PV-lead-acid battery systems are examined and two different cases are investigated; a high solar potential area and a medium solar potential area. By considering that the PV-battery (PV-Bat) system's useful energy production is equal to the remote consumer's electricity consumption, optimum cadmium telluride (CdTe) based systems yield the minimum EPBP (15 years). If achieving to exploit the net PV energy production however, the EPBP is found less than 20 years for all PV types. Finally, the most interesting finding concerns the fact that in all cases examined the contribution of the battery component exceeds 27% of the system LC energy requirements, reflecting the difference between grid-connected and stand-alone configurations.

  4. Fuzzy logic control of stand-alone photovoltaic system with battery storage

    Science.gov (United States)

    Lalouni, S.; Rekioua, D.; Rekioua, T.; Matagne, E.

    Photovoltaic energy has nowadays an increased importance in electrical power applications, since it is considered as an essentially inexhaustible and broadly available energy resource. However, the output power provided via the photovoltaic conversion process depends on solar irradiation and temperature. Therefore, to maximize the efficiency of the photovoltaic energy system, it is necessary to track the maximum power point of the PV array. The present paper proposes a maximum power point tracker (MPPT) method, based on fuzzy logic controller (FLC), applied to a stand-alone photovoltaic system. It uses a sampling measure of the PV array power and voltage then determines an optimal increment required to have the optimal operating voltage which permits maximum power tracking. This method carries high accuracy around the optimum point when compared to the conventional one. The stand-alone photovoltaic system used in this paper includes two bi-directional DC/DC converters and a lead-acid battery bank to overcome the scare periods. One converter works as an MPP tracker, while the other regulates the batteries state of charge and compensates the power deficit to provide a continuous delivery of energy to the load. The Obtained simulation results show the effectiveness of the proposed fuzzy logic controller.

  5. Stand-alone wind system with Vanadium Redox Battery energy storage

    DEFF Research Database (Denmark)

    Teodorescu, Remus; Barote, L.; Weissbach, R.

    2008-01-01

    Energy storage devices are required for power balance and power quality in stand alone wind energy systems. A Vanadium Redox Flow Battery (VRB) system has many features which make its integration with a stand-alone wind energy system attractive. This paper proposes the integration of a VRB system...

  6. Multi-objective analytical model for optimal sizing of stand-alone photovoltaic water pumping systems

    International Nuclear Information System (INIS)

    Olcan, Ceyda

    2015-01-01

    Highlights: • An analytical optimal sizing model is proposed for PV water pumping systems. • The objectives are chosen as deficiency of power supply and life-cycle costs. • The crop water requirements are estimated for a citrus tree yard in Antalya. • The optimal tilt angles are calculated for fixed, seasonal and monthly changes. • The sizing results showed the validity of the proposed analytical model. - Abstract: Stand-alone photovoltaic (PV) water pumping systems effectively use solar energy for irrigation purposes in remote areas. However the random variability and unpredictability of solar energy makes difficult the penetration of PV implementations and complicate the system design. An optimal sizing of these systems proves to be essential. This paper recommends a techno-economic optimization model to determine optimally the capacity of the components of PV water pumping system using a water storage tank. The proposed model is developed regarding the reliability and cost indicators, which are the deficiency of power supply probability and life-cycle costs, respectively. The novelty is that the proposed optimization model is analytically defined for two-objectives and it is able to find a compromise solution. The sizing of a stand-alone PV water pumping system comprises a detailed analysis of crop water requirements and optimal tilt angles. Besides the necessity of long solar radiation and temperature time series, the accurate forecasts of water supply needs have to be determined. The calculation of the optimal tilt angle for yearly, seasonally and monthly frequencies results in higher system efficiency. It is, therefore, suggested to change regularly the tilt angle in order to maximize solar energy output. The proposed optimal sizing model incorporates all these improvements and can accomplish a comprehensive optimization of PV water pumping systems. A case study is conducted considering the irrigation of citrus trees yard located in Antalya, Turkey

  7. Charactrization of a Li-ion battery based stand-alone a-Si photovoltaic system

    International Nuclear Information System (INIS)

    Hamid Vishkasougheh, Mehdi; Tunaboylu, Bahadir

    2014-01-01

    Highlights: • An Li-ion battery based stand-alone a-Si PV was designed. The system composed of three a-Si panels with an efficiency of 7% and 40 cells of LFP batteries. • Effects of solar radiation and environmental temperature for three cities, Istanbul, Ankara, and Adana, have been investigated on a-Si panels. • Using transition formulas BSPV outputs are predictable for any location out of standard test condition. - Abstract: The number of photovoltaic (PV) system installations is increasing rapidly. As more people learn about this versatile and often cost-effective power option, this trend will accelerate. This document presents a recommended design for a battery based stand-alone photovoltaic system (BSPV). BSPV system has the ability to be applied in different areas, including warning signals, lighting, refrigeration, communication, residential water pumping, remote sensing, and cathodic protection. The presented calculation method gives a proper idea for a system sizing technique. Based on application load, different scenarios are possible for designing a BSPV system. In this study, a battery based stand-alone system was designed. The electricity generation part is three a-Si panels, which are connected in parallel, and for the storage part LFP (lithium iron phosphate) battery was used. The high power LFP battery packs are 40 cells each 8S5P (configured 8 series 5 parallel). Each individual pack weighs 0.5 kg and is 25.6 V. In order to evaluate the efficiency of a-Si panels with respect to the temperature and the solar irradiation, cities of Istanbul, Ankara and Adana in Turkey were selected. Temperature and solar irradiation were gathered from reliable sources and by using translation equations, current and voltage output of panels were calculated. As a result of these calculations, current and energy outputs were computed by considering an average efficient solar irradiation time value per day in Turkey. The calculated power values were inserted to a

  8. Comparative analysis of distributed MPPT controllers for partially shaded stand alone photovoltaic systems

    International Nuclear Information System (INIS)

    Muthuramalingam, M.; Manoharan, P.S.

    2014-01-01

    Highlights: • Analyzes the performance of ANN and ANFIS MPPT algorithms by stand alone PV system. • ISSBC with ANFIS can provide the overall efficiency higher than ANN. • CHBMLI integrate with SHE ANN modulation technique improve output voltage quality. • Simulation and hardware results show the ANFIS algorithm efficient than ANN algorithm. - Abstract: This paper presents a unique combination of an interleaved soft switched boost converter (ISSBC) run by a set of two photovoltaic panel (PV) with a distributed MPPT, suitable to guarantee MPPT even under partial shadowed conditions, managed by an adaptive neuro fuzzy inference system trained by the training data derived from a particle swarm optimization (PSO–ANFIS) unit. The ISSBC is followed by a, single phase cascaded H bridge five-level inverter (CHI) driven by the individual DC outputs of the ISSBC, with selective harmonic elimination scheme to eliminate typically the seventh order harmonics. A comparison of different intelligent distributed maximum power point tracking (MPPT) algorithms for photovoltaic (PV) system under partial shadow conditions is carried out. The use of the ISSBC guarantees mitigation of ripple and it is meant to handle higher currents with minimal switching losses. Simulation was carried out in the Matlab Simulink environment and an experimental verification with a scaled down model validated the proposed scheme. It has been thus established, by both simulation and experimental verification, that the PSO–ANFIS model of distributed MPPT scheme of control outperforms other schemes of control for MPPT

  9. Solar photovoltaic applications seminar: design, installation and operation of small, stand-alone photovoltaic power systems

    Energy Technology Data Exchange (ETDEWEB)

    1980-07-01

    This seminar material was developed primarily to provide solar photovoltaic (PV) applied engineering technology to the Federal community. An introduction to photoconductivity, semiconductors, and solar photovoltaic cells is included along with a demonstration of specific applications and application identification. The seminar details general systems design and incorporates most known information from industry, academia, and Government concerning small solar cell power system design engineering, presented in a practical and applied manner. Solar PV power system applications involve classical direct electrical energy conversion and electric power system analysis and synthesis. Presentations and examples involve a variety of disciplines including structural analysis, electric power and load analysis, reliability, sizing and optimization; and, installation, operation and maintenance. Four specific system designs are demonstrated: water pumping, domestic uses, navigational and aircraft aids, and telecommunications. All of the applications discussed are for small power requirement (under 2 kilowatts), stand-alone systems to be used in remote locations. Also presented are practical lessons gained from currently installed and operating systems, problems at sites and their resolution, a logical progression through each major phase of system acquisition, as well as thorough design reviews for each application.

  10. Stand-alone photovoltaic (PV) integrated with earth to air heat exchanger (EAHE) for space heating/cooling of adobe house in New Delhi (India)

    International Nuclear Information System (INIS)

    Chel, Arvind; Tiwari, G.N.

    2010-01-01

    This paper deals with an experimental outdoor annual performance evaluation of 2.32 kW P photovoltaic (PV) power system located at solar energy park in New Delhi composite climatic conditions. This PV system operates the daily electrical load nearly 10 kW h/day which comprises of various applications such as electric air blower of an earth to air heat exchanger (EAHE) used for heating/cooling of adobe house, ceiling fan, fluorescent tube-light, computer, submersible water pump, etc. The outdoor efficiencies, power generated and lost in PV system components were determined using hourly experimental measured data for 1 year on typical clear day in each month. These realistic data are useful for design engineers for outdoor assessment of PV system components. The energy conservation, mitigation of CO 2 emission and carbon credit potential of the existing PV integrated EAHE system is presented in this paper. Also, the energy payback time (EPBT) and unit cost of electricity were determined for both stand-alone PV (SAPV) and building roof integrated PV (BIPV) systems.

  11. Battery Storage Technologies for Electrical Applications: Impact in Stand-Alone Photovoltaic Systems

    Directory of Open Access Journals (Sweden)

    Daniel Akinyele

    2017-11-01

    Full Text Available Batteries are promising storage technologies for stationary applications because of their maturity, and the ease with which they are designed and installed compared to other technologies. However, they pose threats to the environment and human health. Several studies have discussed the various battery technologies and applications, but evaluating the environmental impact of batteries in electrical systems remains a gap that requires concerted research efforts. This study first presents an overview of batteries and compares their technical properties such as the cycle life, power and energy densities, efficiencies and the costs. It proposes an optimal battery technology sizing and selection strategy, and then assesses the environmental impact of batteries in a typical renewable energy application by using a stand-alone photovoltaic (PV system as a case study. The greenhouse gas (GHG impact of the batteries is evaluated based on the life cycle emission rate parameter. Results reveal that the battery has a significant impact in the energy system, with a GHG impact of about 36–68% in a 1.5 kW PV system for different locations. The paper discusses new batteries, strategies to minimize battery impact and provides insights into the selection of batteries with improved cycling capacity, higher lifespan and lower cost that can achieve lower environmental impacts for future applications.

  12. Bifacial PV cell with reflector for stand-alone mast for sensor powering purposes

    DEFF Research Database (Denmark)

    Jakobsen, Michael Linde; Thorsteinsson, Sune; Poulsen, Peter Behrensdorff

    2017-01-01

    Reflectors to bifacial PV-cells are simulated and prototyped in this work. The aim is to optimize the reflector to specific latitudes, and particularly northern latitudes. Specifically, by using minimum semiconductor area the reflector must be able to deliver the electrical power required at the ...... at the condition of minimum solar travel above the horizon, worst weather condition etc. We will test a bifacial PV-module with a retroreflector, and compare the output with simulations combined with local solar data....

  13. Algal Hydrogen Production -- Stand Alone or Integrated System?

    Energy Technology Data Exchange (ETDEWEB)

    Ghirardi, Maria L.; Maness, Pin Ching; Kosourovo, Sergey

    2016-01-01

    Photosynthetic bacteria and green algae photoproduce H2. but do so utilizing different catalysts and substrates. Green algae use reductant generate mostly by water oxidation to catalyze the reduction of protons to H2 gas, while photosynthetic bacteria catalyze H2 production from organic acids using the nitrogenase enzyme. Moreover, these two organisms utilize different regions of the solar spectrum to perform photosynthesis: green algae's light harvesting antenna is comprised of chlorophyll molecules that absorb mostly blue and red light; photosynthetic bacteria harvest blue and far-red light through their light-harvesting pigments to run its non-oxygenic photosynthetic reactions. There is thus an opportunity to increase the range of solar spectrum used to photoproduce H2 by combining the light-harvesting and catalytic properties of these two organisms in a single process. In the current manuscript, we describe an experimental system that validates this hypothesis and demonstrates quantitatively the advantages of a two organism process for production of higher amounts of H2 and thus achieving solar light conversion efficiencies.

  14. Hierarchical energy management system for stand-alone hybrid system based on generation costs and cascade control

    International Nuclear Information System (INIS)

    Torreglosa, J.P.; García, P.; Fernández, L.M.; Jurado, F.

    2014-01-01

    Highlights: • We present an energy management system for a stand-alone WT/PV/hydrogen/battery hybrid system. • Hierarchical control composed by master and slave control strategies. • Control assures reliable electricity support for stand-alone applications subject to technical and economic criteria. - Abstract: This paper presents an energy management system (EMS) for stand-alone hybrid systems composed by photovoltaic (PV) solar panels and a wind turbine (WT) as primary energy sources and two energy storage systems, which are a hydrogen system and a battery. The hydrogen system is composed of fuel cell (FC), electrolyzer and hydrogen storage tank. The EMS is a hierarchical control composed by a master control strategy and a slave control strategy. On the one hand, the master control generates the reference powers to meet several premises (such as to satisfy the load power demand, and to maintain the hydrogen tank level and the state of charge (SOC) of the battery between their target margins), taking also into account economic aspects to discriminate between using the battery or hydrogen system. On the other hand, the slave control modifies the reference powers generated by the master control according to the energy sources dynamic limitations, and maintains the DC bus voltage at its reference value. The models, implemented in MATLAB-Simulink environment, have been developed from commercially available components. To check the viability of the proposed EMS, two kinds of simulations were carried out: (1) A long-term simulation of 25 years (expected lifetime of the system) with a sample time of one hour to validate the master control of the EMS; and (2) A short-term simulation with sudden net power variations to validate the slave control of the EMS

  15. Stand-alone wind system with Vanadium Redox Battery energy storage

    DEFF Research Database (Denmark)

    Teodorescu, Remus; Barote, L.; Weissbach, R.

    2008-01-01

    Energy storage devices are required for power balance and power quality in stand alone wind energy systems. A Vanadium Redox Flow Battery (VRB) system has many features which make its integration with a stand-alone wind energy system attractive. This paper proposes the integration of a VRB system...... with a typical stand-alone wind energy system during wind speed variation as well as transient performance under variable load. The investigated system consists of a variable speed wind turbine with permanent magnet synchronous generator (PMSG), diode rectifier bridge, buck-boost converter, bidirectional charge...... controller, transformer, inverter, ac loads and VRB (to store a surplus of wind energy and to supply power during a wind power shortage). The main purpose is to supply domestic appliances through a single phase 230V, 50Hz inverter. Simulations are accomplished in order to validate the stability of the supply....

  16. Life cycle assessment of stand-alone photovoltaic (SAPV) system under on-field conditions of New Delhi, India

    International Nuclear Information System (INIS)

    Sharma, Rakhi; Tiwari, G.N.

    2013-01-01

    In this paper, life cycle analysis has been carried out to evaluate overall performance of given rated stand-alone solar photovoltaic (SAPV) in terms of basic energy matrices, life cycle cost analysis, and earned carbon credit. Further, the experimentally calculated actual on-field life cycle performance results of existing outdoor SAPV system (i.e. almost 20 years old) have been represented with respect to the potential (max.) performance of same SAPV system estimated under same environmental conditions of solar intensity, ambient temperature, PV operating temperature as obtained during actual on-field performance evaluation. This new approach of overall performance evaluation by considering the on-field SAPV system installation as new (i.e. with potential/max. performance) and old (i.e. with actual performance) under same environmental conditions provides an inclusive comparative life cycle assessment of on-field PV system. - Highlights: • We present comparative life cycle assessment methodology for outdoor PV system. • We evaluate on-field PV system life performance by considering it as new and old. • We examine fall in actual on-field PV performance compared to potential performance. • PV system techno-economic performance reduces with the long term exposure or aging. • We observe fall in earned carbon credit and rise in cost/kWh as PV system ages

  17. Charactrization of a Li-ion battery based stand-alone a-Si photovoltaic system

    Science.gov (United States)

    Hamid Vishkasougheh, Mehdi; Tunaboylu, Bahadir

    2014-11-01

    The number of photovoltaic (PV) system installations is increasing rapidly. As more people learn about this versatile and often cost-effective power option, this trend will accelerate. This document presents a recommended design for a battery based stand-alone photovoltaic system (BSPV). BSPV system has the ability to be applied in different areas, including warning signals, lighting, refrigeration, communication, residential water pumping, remote sensing, and cathodic protection. The presented calculation method gives a proper idea for a system sizing technique. Based on application load, different scenarios are possible for designing a BSPV system. In this study, a battery based stand-alone system was designed. The electricity generation part is three a-Si panels, which are connected in parallel, and for the storage part LFP (lithium iron phosphate) battery was used. The high power LFP battery packs are 40 cells each 8S5P (configured 8 series 5 parallel). Each individual pack weighs 0.5 kg and is 25.6 V. In order to evaluate the efficiency of a-Si panels with respect to the temperature and the solar irradiation, cities of Istanbul, Ankara and Adana in Turkey were selected. Temperature and solar irradiation were gathered from reliable sources and by using translation equations, current and voltage output of panels were calculated. As a result of these calculations, current and energy outputs were computed by considering an average efficient solar irradiation time value per day in Turkey. The calculated power values were inserted to a battery cycler system, and the behavior of high power LFP batteries in a time sequence of 7.2 h was evaluated. The charging and discharging cycles were obtained and their behavior was discussed. According to the results, Istanbul has the lowest number of peak month's energy, it followed by Ankara, and ultimately Adana has the highest number of peak months and energy storage. It was observed during the tests that values up to 4 A was

  18. Stand alone solar energy harvesting and storage systems in off-grid applications

    Science.gov (United States)

    Alonso-Marroquin, Fernando; Gormly, Justin Blake; Bilbao, Jose

    2017-06-01

    The following is an implementation of a stand-alone system for solar energy harvesting and electrical energy storage systems for use in off-grid housing applications. The principal aim of this project was to construct a compact and affordable system for an off-grid house and to monitor its efficiency along the year.

  19. MOSFET Loss Evaluation for a Low-Power Stand-Alone Photovoltaic-LED System

    DEFF Research Database (Denmark)

    Mira Albert, Maria del Carmen; Knott, Arnold; Andersen, Michael A. E.

    2015-01-01

    This paper presents a performance evaluation and comparison of state-of-the-art low voltage Si MOSFETs for a stand-alone photovoltaic-LED Light to Light (LtL) system. The complete system is formed by two cascaded converters that will be optimized for a determined solar irradiation and LED...

  20. Optimum capacity determination of stand-alone hybrid generation system considering cost and reliability

    International Nuclear Information System (INIS)

    Chen, Hung-Cheng

    2013-01-01

    Highlights: ► This paper presents a methodology for the installation capacity optimization. ► Hybrid generation system is optimized by application of adaptive genetic algorithm. ► A cost investigation is made under various conditions and component characteristics. ► The optimization scheme is validated to meet the annual power load demand. -- Abstract: The aim of this work is to present an optimization methodology for the installation capacity of a stand-alone hybrid generation system, taking into consideration the cost and reliability. Firstly, on the basis of derived steady state models of a wind generator (WG), a photovoltaic array (PV), a battery and an inverter, the hybrid generation system is modeled for the purpose of capacity optimization. Secondly, the power system is analyzed for determining both the system structure and the operation control strategy. Thirdly, according to hourly weather database of wind speed, temperature and solar irradiation, annual power generation capacity is estimated for the system match design in order that an annual power load demand can be met. The capacity determination of a hybrid generation system becomes complicated as a result of the uncertainty in the renewable energy together with load demand and the nonlinearity of system components. Aimed at the power system reliability and the cost minimization, the capacity of a hybrid generation system is optimized by application of an adaptive genetic algorithm (AGA) to individual power generation units. A total cost investigation is made under various conditions, such as wind generator power curves, battery discharge depth and the loss of load probability (LOLP). At the end of this work, the capacity of a hybrid generation system is optimized at two installation sites, namely the offshore Orchid Island and Wuchi in Taiwan. The optimization scheme is validated to optimize power capacities of a photovoltaic array, a battery and a wind turbine generator with a relative

  1. Feasibility study and energy conversion analysis of stand-alone hybrid renewable energy system

    International Nuclear Information System (INIS)

    Baghdadi, Fazia; Mohammedi, Kamal; Diaf, Said; Behar, Omar

    2015-01-01

    Highlights: • Hybrid stand-alone wind–solar–fossil power system is analyzed. • Measurement data are used to evaluate system performance. • The proposed system can generate about 70% from renewables. • Such a hybrid plant is very promising for remote regions in Algeria. - Abstract: There is a great interest in the development of renewable power technologies in Algeria, and more particularly hybrid concept. The present paper has investigated the performance of hybrid PV–Wind–Diesel–Battery configuration based on hourly measurements of Adrar climate (southern Algeria). Data of global solar radiation, ambient temperature and wind speed for a period of one year have been used. Firstly, the proposed hybrid system has been optimized by means of HOMER software. The optimization process has been carried out taking into account renewable resources potential and energy demand; while maximizing renewable electricity use and fuel saving are the purpose. In the second step, a mathematical model has been developed to ensure efficient energy management on the basis of various operation strategies. The analysis has shown that renewable energy system (PV–Wind) is able to supply about 70% of the demand. Wind power has ranked first with 43% of the annual total electricity production followed by diesel generator (with 31%) while the remaining fraction is being to PV panels. In this context, 69% of the fossil fuel can be saved when using the proposed hybrid configuration instead of the diesel generators that are currently installed in most remote regions in Algeria. Such a concept is very promising to meet the focus of renewable energy program announced in 2011.

  2. Stand-Alone Photovoltaic System Assessment in Warmer Urban Areas in Mexico

    Directory of Open Access Journals (Sweden)

    Alberto-Jesus Perea-Moreno

    2018-01-01

    Full Text Available The aim of this study is to examine the possibility of using a stand-alone photovoltaic system (SAPVS for electricity generation in urban areas in Southern Mexico. In Mexico, an urban area is defined as an area where more than 2500 inhabitants live. Due to constant migration from the countryside to the cities, the number of inhabitants of urban localities has been increasing. Global horizontal irradiation (GHI data were recorded every 10 min during 2014–2016 in Coatzacoalcos in the state of Veracruz located on 18°08′09″ N and 94°27′48″ W. In this study, batteries represented 77% of the total cost, 12 PV panels of 310 W could export 5.41 MWh to the grid, and an inverter with an integrated controller and charger was selected, which decreased the initial cost. The city of Coatzacoalcos was chosen because the average annual temperature is 28°, with an average relative humidity of 75% and an average irradiance of 5.3 kWh/m2/day. An emission factor 0.505 tCO2/MWh of greenhouse gases (GHG were obtained, based on the power system, the reduction of net annual GHG would be 11 tCO2 and a financial revenue of 36.951 × 103 $/tCO2 would be obtained. Financial parameters such as a 36.3% Internal Rate Return (IRR and 3.4 years payback show the financial viability of this investment. SAPVSs in urban areas in Mexico could be a benefit as long as housing has a high consumption of electricity.

  3. Information systems for the materials management department: stand-alone and enterprise resource planning systems.

    Science.gov (United States)

    2005-03-01

    Materials management information systems (MMISs) incorporate information tools that hospitals can use to automate certain business processes, increase staff compliance with these processes, and identify opportunities for cost savings. Recently, there has been a push by hospital administration to purchase enterprise resource planning (ERP) systems, information systems that promise to integrate many more facets of healthcare business. We offer this article to help materials managers, administrators, and others involved with information system selection understand the changes that have taken place in materials management information systems, decide whether they need a new system and, if so, whether a stand-alone MMIS or an ERP system will be the best choice.

  4. Secure stand alone positive personnel identity verification system (SSA-PPIV)

    International Nuclear Information System (INIS)

    Merillat, P.D.

    1979-03-01

    The properties of a secure stand-alone positive personnel identity verification system are detailed. The system is designed to operate without the aid of a central computing facility and the verification function is performed in the absence of security personnel. Security is primarily achieved by means of data encryption on a magnetic stripe badge. Several operational configurations are discussed. Advantages and disadvantages of this system compared to a central computer driven system are detailed

  5. Stand-alone power systems for the future: Optimal design, operation and control of solar-hydrogen energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Ulleberg, Oeystein

    1998-12-31

    This thesis gives a systematic review of the fundamentals of energy systems, the governing physical and chemical laws related to energy, inherent characteristics of energy system, and the availability of the earth`s energy. It shows clearly why solar-hydrogen systems are one of the most viable options for the future. The main subject discussed is the modelling of SAPS (Stand-Alone Power Systems), with focus on photovoltaic-hydrogen energy systems. Simulation models for a transient simulation program are developed for PV-H{sub 2} components, including models for photovoltaics, water electrolysis, hydrogen storage, fuel cells, and secondary batteries. A PV-H{sub 2} demonstration plant in Juelich, Germany, is studied as a reference plant and the models validated against data from this plant. Most of the models developed were found to be sufficiently accurate to perform short-term system simulations, while all were more than accurate enough to perform long-term simulations. Finally, the verified simulation models are used to find the optimal operation and control strategies of an existing PV-H{sub 2} system. The main conclusion is that the simulation methods can be successfully used to find optimal operation and control strategies for a system with fixed design, and similar methods could be used to find alternative system designs. 148 refs., 78 figs., 31 tabs.

  6. Adaptive Artificial intelligence based fuzzy logic MPPTcontrol for stande-alone photovoltaic system under different atmospheric conditions

    Directory of Open Access Journals (Sweden)

    Zaghba Layachi

    2015-08-01

    Full Text Available there is an increased need for analysing the effect of atmospheric variables on photovoltaic (PV production and performance. The outputs from the different PV cells in different atmospheric conditions, such as irradiation and temperature , differ from each other evidencing knowledge deficiency in PV systems [14]. Maximum power point tracking (MPPT methods are used to maximize the PV array output power by tracking continuously the maximum power point (MPP. Among all MPPT methods existing in the literature, perturb and observe (P&O is the most commonly used for its simplicity and ease of implementation; however, it presents drawbacks such as slow response speed, oscillation around the MPP in steady state, and even tracking in wrong way under rapidly changing atmospheric conditions. In order to allow a functioning around the optimal point Mopt, we have inserted a DC-DC converter (Buck–Boost for a better matching between the PV and the load. This paper, we study the Maximum power point tracking using adaptive Intelligent fuzzy logic and conventional (P&O control for stande-alone photovoltaic Array system .In particular, the performances of the controllers are analyzed under variation weather conditions with are constant temperature and variable irradiation. The proposed system is simulated by using MATLAB-SIMULINK. According to the results, fuzzy logic controller has shown better performance during the optimization.

  7. Supervisory control applied to stand-alone photovoltaic systems based on multi string topology; Controle supervisorio aplicado a sistemas fotovoltaicos autonomos com topologia multi string

    Energy Technology Data Exchange (ETDEWEB)

    Candido, Diogo Brum

    2010-07-01

    This master thesis analyses and implements a stand-alone photovoltaic system based on decentralized 'Multi String' topology. The proposed system is composed of a set of DC-DC converters linked to the PV arrays of panels, a bidirectional converter to perform the control of the charge/discharge process of the battery bank and ensure the specifications of DC link and a full-bridge inverter that feed the AC loads. Therefore, all operation modes that the stand-alone PV system can work are presented and analyzed. As the chief aim is to ensure the energy balance of the stand-alone PV system, are presented independents control loops for each converter of the PV system and a propose of a supervisory control that, based on information about the conditions of the DC link and the bank of batteries, defines each operation mode should be active, in order to maximize the power extracted from the PV arrays, the life cycle of the battery bank and ensuring the uninterrupted feeding of energy to the loads. Finally, simulation and experimental results validate the operation of the proposed system under different load and solar radiation conditions. (author)

  8. A Three-Port Topology Comparison for a Low Power Stand-Alone Photovoltaic System

    DEFF Research Database (Denmark)

    Mira Albert, Maria del Carmen; Knott, Arnold; Andersen, Michael A. E.

    2014-01-01

    Three-port converter (TPC) topologies for renewable energy systems aim to provide higher efficiency and power density than conventional cascaded structures. This work proposes an analytical comparison of different TPC topologies for a photovoltaic LED lamp stand-alone system. A comparison using...... component stress factor (CSF) is performed, which gives a quantitative measure of the performance of the converter. The candidate topologies are compared to each other according to a defined LED lighting strategy and a solar irradiation profile....

  9. Economic and Environmental Assessment of a Renewable Stand-Alone Energy Supply System Using Multi-objective Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dohyun; Han, Seulki; Kim, Jiyong Kim [Incheon National University, Incheon (Korea, Republic of)

    2017-06-15

    This study aims to propose a new optimization-based approach for design and analysis of the stand-alone hybrid energy supply system using renewable energy sources (RES). In the energy supply system, we include multiple energy production technologies such as Photovoltaics (PV), Wind turbine, and fossil-fuel-based AC generator along with different types of energy storage and conversion technologies such as battery and inverter. We then select six different regions of Korea to represent various characteristics of different RES potentials and demand profiles. We finally designed and analyzed the optimal RES stand-alone energy supply system in the selected regions using multiobjective optimization (MOOP) technique, which includes two objective functions: the minimum cost and the minimum CO{sub 2} emission. In addition, we discussed the feasibility and expecting benefits of the systems by comparing to conventional systems of Korea. As a result, the region of the highest RES potential showed the possibility to remarkably reduce CO{sub 2} emissions compared to the conventional system. Besides, the levelized cost of electricity (LCOE) of the RES-based energy system is identified to be slightly higher than conventional energy system: 0.35 and 0.46 $/kWh, respectively. However, the total life-cycle emission of CO{sub 2} (LCECO{sub 2}) can be reduced up to 470 gCO{sub 2}/kWh from 490 gCO{sub 2}/kWh of the conventional systems.

  10. Life cycle assessment study of a 4.2 kW{sub p} stand-alone photovoltaic system

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Valverde, R.; Miguel, C.; Urbina, A. [Universidad Politecnica de Cartagena, Departamento de Electronica, Tecnologia de Computadoras y Proyectos, Campus Muralla del Mar, 30203, Cartagena, Murcia (Spain); Martinez-Bejar, R. [Universidad de Murcia, Departamento de Ingenieria de la Informacion y las Comunicaciones, Facultad de Informatica, Campus de Espinardo, 30071, Murcia (Spain)

    2009-09-15

    The energetic and environmental life cycle assessment of a 4.2 kW{sub p} stand-alone photovoltaic system (SAPV) at the University of Murcia (south-east of Spain) is presented. PV modules and batteries are the energetically and environmentally most expensive elements. The energy pay-back time was found to be 9.08 years and the specific CO{sub 2} emissions was calculated as 131 g/kWh. The SAPV system has been environmentally compared with other supply options (diesel generator and Spanish grid) showing lower impacts in both cases. The results show the CO{sub 2}-emission reduction potential of SAPV systems in southern European countries and point out the critical environmental issues in these systems. (author)

  11. Energy management system for stand-alone diesel-wind-biomass microgrid with energy storage system

    International Nuclear Information System (INIS)

    Wang, Chengshan; Liu, Yixin; Li, Xialin; Guo, Li; Qiao, Lei; Lu, Hai

    2016-01-01

    An energy management system for stand-alone microgrid composed of diesel generators, wind turbine generator, biomass generator and an ESS (energy storage system) is proposed in this paper. Different operation objectives are achieved by a hierarchical control structure with different time scales. Firstly, the optimal schedules of the diesel generators, wind turbine generator, biomass generator and ESS are determined fifteen minutes ahead according to the super short-term forecast of load and wind speed in the optimal scheduling layer. Comprehensive analysis which takes the uncertainty of load and wind speed into account is conducted in this layer to minimize the operation cost of the system and ensure a desirable range of the state of charge of the ESS. Secondly, the operation points of each unit are regulated dynamically to guarantee real-time power balance and safety range of diesel generation in the real-time control layer, based on which the response capability when suffering significant forecast deviation and other emergency issues, e.g. sudden load-up can be improved. Finally, the effectiveness of the proposed energy management strategy is verified on an RT_Lab based real-time simulation platform, and the economic performances with different types of ESS are analyzed as well. - Highlights: • A hierarchical control strategy is proposed for a stand-alone microgrid. • The uncertainties of load and wind speed have been considered. • Better economic performance and high reliability of the system can be achieved. • The influences of different energy storage systems have been analyzed.

  12. Boost converter with combined control loop for a stand-alone photovoltaic battery charge system

    DEFF Research Database (Denmark)

    Mira Albert, Maria del Carmen; Knott, Arnold; Thomsen, Ole Cornelius

    2013-01-01

    frequency avoids perturbations in the load being propagated to the photovoltaic panel and thus deviating the operating point. Linearization of the photovoltaic panel and converter state-space modeling is performed. In order to achieve stable operation under all operating conditions, the photovoltaic panel......The converter control scheme plays an important role in the performance of maximum power point tracking (MPPT) algorithms. In this paper, an input voltage control with double loop for a stand-alone photovoltaic system is designed and tested. The inner current control loop with high crossover...

  13. Feasibility and Optimal Design of a Stand-Alone Photovoltaic Energy System for the Orphanage

    Directory of Open Access Journals (Sweden)

    Vincent Anayochukwu Ani

    2014-01-01

    Full Text Available Access to electricity can have a positive psychological impact through a lessening of the sense of exclusion, and vulnerability often felt by the orphanages. This paper presented the simulation and optimization study of a stand-alone photovoltaic power system that produced the desired power needs of an orphanage. Solar resources for the design of the system were obtained from the National Aeronautics and Space Administration (NASA Surface Meteorology and Solar Energy website at a location of 6°51′N latitude and 7°35′E longitude, with annual average solar radiation of 4.92 kWh/m2/d. This study is based on modeling, simulation, and optimization of energy system in the orphanage. The patterns of load consumption within the orphanage were studied and suitably modeled for optimization. Hybrid Optimization Model for Electric Renewables (HOMER software was used to analyze and design the proposed stand-alone photovoltaic power system model. The model was designed to provide an optimal system configuration based on an hour-by-hour data for energy availability and demands. A detailed design, description, and expected performance of the system were presented in this paper.

  14. Robust Power Management Control for Stand-Alone Hybrid Power Generation System

    International Nuclear Information System (INIS)

    Kamal, Elkhatib; Adouane, Lounis; Aitouche, Abdel; Mohammed, Walaa

    2017-01-01

    This paper presents a new robust fuzzy control of energy management strategy for the stand-alone hybrid power systems. It consists of two levels named centralized fuzzy supervisory control which generates the power references for each decentralized robust fuzzy control. Hybrid power systems comprises: a photovoltaic panel and wind turbine as renewable sources, a micro turbine generator and a battery storage system. The proposed control strategy is able to satisfy the load requirements based on a fuzzy supervisor controller and manage power flows between the different energy sources and the storage unit by respecting the state of charge and the variation of wind speed and irradiance. Centralized controller is designed based on If-Then fuzzy rules to manage and optimize the hybrid power system production by generating the reference power for photovoltaic panel and wind turbine. Decentralized controller is based on the Takagi-Sugeno fuzzy model and permits us to stabilize each photovoltaic panel and wind turbine in presence of disturbances and parametric uncertainties and to optimize the tracking reference which is given by the centralized controller level. The sufficient conditions stability are formulated in the format of linear matrix inequalities using the Lyapunov stability theory. The effectiveness of the proposed Strategy is finally demonstrated through a SAHPS (stand-alone hybrid power systems) to illustrate the effectiveness of the overall proposed method. (paper)

  15. International market assessment of stand-alone photovoltaic power systems for cottage industry applications

    Science.gov (United States)

    Philippi, T. M.

    1981-01-01

    The final result of an international assessment of the market for stand-alone photovoltaic systems in cottage industry applications is reported. Nonindustrialized countries without centrally planned economies were considered. Cottage industries were defined as small rural manufacturers, employing less than 50 people, producing consumer and simple products. The data to support this analysis were obtained from secondary and expert sources in the U.S. and in-country field investigations of the Philippines and Mexico. The near-term market for photovoltaics for rural cottage industry applications appears to be limited to demonstration projects and pilot programs, based on an in-depth study of the nature of cottage industry, its role in the rural economy, the electric energy requirements of cottage industry, and a financial analysis of stand-alone photovoltaic systems as compared to their most viable competitor, diesel driven generators. Photovoltaics are shown to be a better long-term option only for very low power requirements. Some of these uses would include clay mixers, grinders, centrifuges, lathes, power saws and lighting of a workshop.

  16. International market assessment of stand-alone photovoltaic power systems for cottage industry applications

    Science.gov (United States)

    Philippi, T. M.

    1981-11-01

    The final result of an international assessment of the market for stand-alone photovoltaic systems in cottage industry applications is reported. Nonindustrialized countries without centrally planned economies were considered. Cottage industries were defined as small rural manufacturers, employing less than 50 people, producing consumer and simple products. The data to support this analysis were obtained from secondary and expert sources in the U.S. and in-country field investigations of the Philippines and Mexico. The near-term market for photovoltaics for rural cottage industry applications appears to be limited to demonstration projects and pilot programs, based on an in-depth study of the nature of cottage industry, its role in the rural economy, the electric energy requirements of cottage industry, and a financial analysis of stand-alone photovoltaic systems as compared to their most viable competitor, diesel driven generators. Photovoltaics are shown to be a better long-term option only for very low power requirements. Some of these uses would include clay mixers, grinders, centrifuges, lathes, power saws and lighting of a workshop.

  17. Design of Stand-Alone Hybrid Power Generation System at Brumbun Beach Tulungagung East Java

    Science.gov (United States)

    Rahmat, A. N.; Hidayat, M. N.; Ronilaya, F.; Setiawan, A.

    2018-04-01

    Indonesian government insists to optimize the use of renewable energy resources in electricity generation. One of the efforts is launching Independent Energy Village plan. This program aims to fulfill the need of electricity for isolated or remote villages in Indonesia. In order to support the penetration of renewable energy resources in electricity generation, a hybrid power generation system is developed. The simulation in this research is based on the availability of renewable energy resources in Brumbun beach, Tulungagung, East Java. Initially, the electricity was supplied through stand-alone electricity generations which are installed at each house. Hence, the use of electricity between 5 p.m. – 9 p.m. requires high operational costs. Based on the problem above, this research is conducted to design a stand-alone hybrid electricity generation system, which may consist of diesel, wind, and photovoltaic. The design is done by using HOMER software to optimize the use of electricity from renewable resources and to reduce the operation of diesel generation. The combination of renewable energy resources in electricity generation resulted in NPC of 44.680, COE of 0,268, and CO2 emissions of 0,038 % much lower than the use of diesel generator only.

  18. Modeling and Experimental Test of Grid-Tied Photovoltaic Cell Emulating System in the Stand-alone Mode

    Directory of Open Access Journals (Sweden)

    Vu Minh Phap

    2017-06-01

    Full Text Available In recent decades, generation of electricity from solar arrays has been increased to meet the world's growing energy demand. However, the utilization rate of the power conditioner in the grid-tied solar power system is low because the operation of solar panels is dependent on sunlight. Thus, we studied the method that the small scale wind power generating system in size from a few hundred watts to two or three kilowatts can be connected to the grid-tied power conditioner of the solar power system for residential applications with low power ratings (single phase, size is limited to 10kW by emulating characteristic of the solar panel. In this paper, we introduce the application of the grid-tied PV cell emulating system in the stand-alone mode to improve the utilization rate of the power conditioner. The simulation and experimental test results verify that the PV cell emulating system can operate the power conditioner of the gridtied solar power system.

  19. System Simulation by Recursive Feedback: Coupling a Set of Stand-Alone Subsystem Simulations

    Science.gov (United States)

    Nixon, D. D.

    2001-01-01

    Conventional construction of digital dynamic system simulations often involves collecting differential equations that model each subsystem, arran g them to a standard form, and obtaining their numerical gin solution as a single coupled, total-system simultaneous set. Simulation by numerical coupling of independent stand-alone subsimulations is a fundamentally different approach that is attractive because, among other things, the architecture naturally facilitates high fidelity, broad scope, and discipline independence. Recursive feedback is defined and discussed as a candidate approach to multidiscipline dynamic system simulation by numerical coupling of self-contained, single-discipline subsystem simulations. A satellite motion example containing three subsystems (orbit dynamics, attitude dynamics, and aerodynamics) has been defined and constructed using this approach. Conventional solution methods are used in the subsystem simulations. Distributed and centralized implementations of coupling have been considered. Numerical results are evaluated by direct comparison with a standard total-system, simultaneous-solution approach.

  20. Optimal expansion planning of stand-alone systems with stochastic simulations

    Energy Technology Data Exchange (ETDEWEB)

    Hoese, Alejandro [Instituto de Energia Electrica (IEE), Universidad Nacional de San Juan, (Argentina)

    1997-12-31

    Stand-alone systems in the range of 1 kW - 10 MW are taking relevance in the new (global) liberal concept of energy market. State and private investors are becoming increasingly attention on the use of renewable for these systems, but it must be shown that these non-conventional solutions are competitive with the established conventional ones. The high investment costs and the technical and economic uncertainties coupled with the use of time-dependent energy sources are the mainly inhibiting factors for the decision agents to choose these systems instead of conventional ones. In the paper a new model for optimal expansion planning of hybrid stand-alone generating systems under consideration of uncertainties is presented. This model is at present in {sup d}evelopment state{sup .} Results already obtained in the first steps of this research are promising and some of them are here presented. [Espanol] Los sistemas autocontenidos en el rango de 1 Kw a 10 MW estan tomando importancia en el nuevo (global) concepto liberal del mercado de la energia. Inversionistas privados y del Estado estan poniendo mayor atencion en el uso de energias renovables para estos sistemas, pero debe mostrarse que estas soluciones no-convencionales son competitivas con las convencionales establecidas. Los altos costos de inversion y las incertidumbres tecnicas y economicas aunadamente con el uso de fuentes de energia dependientes del tiempo son los principales factores inhibidores de los factores de decision para escoger estos sistemas en lugar de los convencionales. En este articulo se presenta un nuevo modelo de planeacion de expansion optima de sistemas hibridos autocontenidos de generacion electrica bajo la consideracion de incertidumbres. Este modelo esta actualmente en {sup e}stado de desarrollo{sup .} Los resultados ya obtenidos en las primeras etapas de esta investigacion son prometedores y se presentan algunos de ellos.

  1. An adaptive artificial neural network model for sizing stand-alone photovoltaic systems: Application for isolated sites in Algeria

    International Nuclear Information System (INIS)

    Mellit, A.; Benghanem, M.; Hadj Arab, A.; Guessoum, G.

    2004-07-01

    In this paper we investigate, by using an adaptive Artificial Neural Network (ANN), in order to find a suitable model for sizing Stand-Alone Photovoltaic (SAPV) systems, based on a minimum of input data. This model combines Radial Basis Function (RBF) network and Infinite Impulse Response (IIR) filter in order to accelerate the convergence of the network. For the sizing of a photovoltaic (PV) system, we need to determine the optimal sizing coefficients (K PV , K B . These coefficients allow us to determine the number of solar panels and storage batteries necessary to satisfy a given consumption, especially in isolated sites where the global solar radiation data is not always available and which are considered the most important parameters for sizing a PV system. Obtained results by classical models (analytical, numerical, analytical- numerical, B-spline function) and new models like feed-forward (MLP), radial basis function (RBF), MLP-IIR and RBF-IIR have been compared with experimental sizing coefficients in order to illustrate the accuracy of the results of the new developed model. This model has been trained by using 200 known optimal sizing coefficients corresponding to 200 locations in Algeria. In this way, the adaptive model was trained to accept and even handle a number of unusual cases, the unknown validation sizing coefficients set produced very set accurate estimation and a correlation coefficient of 98% was obtained between the calculated and that estimated by the RBF-IIR model. This result indicates that the proposed method can be successfully used for the estimation of optimal sizing coefficients of SAPV systems for any locations in Algeria, but the methodology can be generalized using different locations over the world. (author)

  2. Performance of a small stand alone photovoltaic-wind system at El Oyameyo D.F., Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Juarez, A.; Campos, J. [Centro de Investigacion en Energia, UNAM, Mexico, D. F. (Mexico); Tiburcio Silver, A. [Instituto Tecnologico de Toluca-Division de Posgrado, Toluca (Mexico)

    1997-12-31

    El Oyameyo, is an ecological site located to the South-West of the Topilejo town, D.F., 19 degree 25` North latitude, 99 degree 5` West longitude and at an altitude of 3100 m. At present, there are 10 families living at this place. They have energy generators to produce their own electricity by means of solar or wind energy using photovoltaic (PV) technology and eolic systems, respectively. There are three different configurations of energy generators: DC regulated PV systems, AC regulated PV systems and one PV-Wind hybrid system. The electrical power installed for the stand alone PV systems are from 48 W-p up to 768 W-p range. Among these, there are 4 PV systems that are configurated in DC regulated systems, and other 6 are AC regulated systems. All these systems use lead-acid battery (scaled or vented) banks to store the energy produced daily by the systems. The PV-Wind hybrid system in formed, at present, by a 5.0 kW wind generator, a PV array of 768 W-p, a 37.8 kW-h storage battery bank and a 5.0 kW DC/AC inverter. In this work, we report the electricity generated, load pattern and overall system performance of the photovoltaic-wind hybrid system. The technical characteristics, energy test on the hybrid system and the experience obtained from energy handling and system maintenance for all the systems are presented. We found that all the systems had shown good performance and users` satisfaction. [Espanol] El Oyameyo es un lugar ecologico localizado al Sur-Oeste del pueblo de Topilejo, D. F., 19 grados 25` de latitud Norte 99 grados 5` de longitud Oeste y a una altitud de 3100m. Actualmente hay 10 familias viviendo en este lugar. Tienen generadores de energia para producir su propia electricidad mediante la energia solar y la del viento usando sistemas fotovoltaicos (FV) y sistemas eolicos, respectivamente. Hay tres diferentes configuraciones de generadores de energia: sistemas fotovoltaicos de CD regulados, sistemas fotovoltaicos de CA regulados y un sistema

  3. Multi-Objective Optimal Design of Stand-Alone Hybrid Energy System Using Entropy Weight Method Based on HOMER

    Directory of Open Access Journals (Sweden)

    Jiaxin Lu

    2017-10-01

    Full Text Available Implementation of hybrid energy system (HES is generally considered as a promising way to satisfy the electrification requirements for remote areas. In the present study, a novel decision making methodology is proposed to identify the best compromise configuration of HES from a set of feasible combinations obtained from HOMER. For this purpose, a multi-objective function, which comprises four crucial and representative indices, is formulated by applying the weighted sum method. The entropy weight method is employed as a quantitative methodology for weighting factors calculation to enhance the objectivity of decision-making. Moreover, the optimal design of a stand-alone PV/wind/battery/diesel HES in Yongxing Island, China, is conducted as a case study to validate the effectiveness of the proposed method. Both the simulation and optimization results indicate that, the optimization method is able to identify the best trade-off configuration among system reliability, economy, practicability and environmental sustainability. Several useful conclusions are given by analyzing the operation of the best configuration.

  4. Stand-Alone Solar Organic Rankine Cycle Water Pumping System and Its Economic Viability in Nepal

    Directory of Open Access Journals (Sweden)

    Suresh Baral

    2015-12-01

    Full Text Available The current study presents the concept of a stand-alone solar organic Rankine cycle (ORC water pumping system for rural Nepalese areas. Experimental results for this technology are presented based on a prototype. The economic viability of the system was assessed based on solar radiation data of different Nepalese geographic locations. The mechanical power produced by the solar ORC is coupled with a water pumping system for various applications, such as drinking and irrigation. The thermal efficiency of the system was found to be 8% with an operating temperature of 120 °C. The hot water produced by the unit has a temperature of 40 °C. Economic assessment was done for 1-kW and 5-kW solar ORC water pumping systems. These systems use different types of solar collectors: a parabolic trough collector (PTC and an evacuated tube collector (ETC. The economic analysis showed that the costs of water are $2.47/m3 (highest and $1.86/m3 (lowest for the 1-kW system and a 150-m pumping head. In addition, the cost of water is reduced when the size of the system is increased and the pumping head is reduced. The minimum volumes of water pumped are 2190 m3 and 11,100 m3 yearly for 1 kW and 5 kW, respectively. The payback period is eight years with a profitability index of 1.6. The system is highly feasible and promising in the context of Nepal.

  5. Stand-alone flat-plate photovoltaic power systems: System sizing and life-cycle costing methodology for Federal agencies

    Science.gov (United States)

    Borden, C. S.; Volkmer, K.; Cochrane, E. H.; Lawson, A. C.

    1984-01-01

    A simple methodology to estimate photovoltaic system size and life-cycle costs in stand-alone applications is presented. It is designed to assist engineers at Government agencies in determining the feasibility of using small stand-alone photovoltaic systems to supply ac or dc power to the load. Photovoltaic system design considerations are presented as well as the equations for sizing the flat-plate array and the battery storage to meet the required load. Cost effectiveness of a candidate photovoltaic system is based on comparison with the life-cycle cost of alternative systems. Examples of alternative systems addressed are batteries, diesel generators, the utility grid, and other renewable energy systems.

  6. Probabilistic modelling and analysis of stand-alone hybrid power systems

    International Nuclear Information System (INIS)

    Lujano-Rojas, Juan M.; Dufo-López, Rodolfo; Bernal-Agustín, José L.

    2013-01-01

    As a part of the Hybrid Intelligent Algorithm, a model based on an ANN (artificial neural network) has been proposed in this paper to represent hybrid system behaviour considering the uncertainty related to wind speed and solar radiation, battery bank lifetime, and fuel prices. The Hybrid Intelligent Algorithm suggests a combination of probabilistic analysis based on a Monte Carlo simulation approach and artificial neural network training embedded in a genetic algorithm optimisation model. The installation of a typical hybrid system was analysed. Probabilistic analysis was used to generate an input–output dataset of 519 samples that was later used to train the ANNs to reduce the computational effort required. The generalisation ability of the ANNs was measured in terms of RMSE (Root Mean Square Error), MBE (Mean Bias Error), MAE (Mean Absolute Error), and R-squared estimators using another data group of 200 samples. The results obtained from the estimation of the expected energy not supplied, the probability of a determined reliability level, and the estimation of expected value of net present cost show that the presented model is able to represent the main characteristics of a typical hybrid power system under uncertain operating conditions. - Highlights: • This paper presents a probabilistic model for stand-alone hybrid power system. • The model considers the main sources of uncertainty related to renewable resources. • The Hybrid Intelligent Algorithm has been applied to represent hybrid system behaviour. • The installation of a typical hybrid system was analysed. • The results obtained from the study case validate the presented model

  7. An improved synchronous reference frame phase-locked loop for stand-alone variable speed constant frequency power generation systems

    DEFF Research Database (Denmark)

    Liu, Yi; Xu, Wei; Ke, Longzhang

    2017-01-01

    The phase-locked loop (PLL) based on conventional synchronous reference frame, i.e. dqPLL, is usually employed in grid-connected variable speed constant frequency (VSCF) power generation systems (PGSs). However, the voltage amplitude drop of stand-alone PGSs is often greater than that of the grid...

  8. A Low-Power Wearable Stand-Alone Tongue Drive System for People With Severe Disabilities.

    Science.gov (United States)

    Jafari, Ali; Buswell, Nathanael; Ghovanloo, Maysam; Mohsenin, Tinoosh

    2018-02-01

    This paper presents a low-power stand-alone tongue drive system (sTDS) used for individuals with severe disabilities to potentially control their environment such as computer, smartphone, and wheelchair using their voluntary tongue movements. A low-power local processor is proposed, which can perform signal processing to convert raw magnetic sensor signals to user-defined commands, on the sTDS wearable headset, rather than sending all raw data out to a PC or smartphone. The proposed sTDS significantly reduces the transmitter power consumption and subsequently increases the battery life. Assuming the sTDS user issues one command every 20 ms, the proposed local processor reduces the data volume that needs to be wirelessly transmitted by a factor of 64, from 9.6 to 0.15 kb/s. The proposed processor consists of three main blocks: serial peripheral interface bus for receiving raw data from magnetic sensors, external magnetic interference attenuation to attenuate external magnetic field from the raw magnetic signal, and a machine learning classifier for command detection. A proof-of-concept prototype sTDS has been implemented with a low-power IGLOO-nano field programmable gate array (FPGA), bluetooth low energy, battery and magnetic sensors on a headset, and tested. At clock frequency of 20 MHz, the processor takes 6.6 s and consumes 27 nJ for detecting a command with a detection accuracy of 96.9%. To further reduce power consumption, an application-specified integrated circuit processor for the sTDS is implemented at the postlayout level in 65-nm CMOS technology with 1-V power supply, and it consumes 0.43 mW, which is 10 lower than FPGA power consumption and occupies an area of only 0.016 mm.

  9. The Stand-alone Heliostat

    International Nuclear Information System (INIS)

    Garcia Navajas, G. I.; Egea Gea, A.

    2000-01-01

    The first Autonomous Heliostat has been developed by CIEMAT at PSA facilities in Almeria. This heliostat is an innovative approach to reducing the civil engineering work costs in heliostat fields of central tower plants. Channels, cables and other electric elements have been eliminated in the new heliostat. Thus, one 70-nr, classical T glass/metal heliostat has been adapted to include all the new stand-alone concept components. A PV system is able to drive two sun-tracking DC motors between 5 and 24Vdc, 0 and 15A. The heliostat communicates with the control room 400-m away by using a radio-modem working at 9600 baud. An anemometer, a wind switcher, light and ambient temperature sensors have been installed on the heliostat for self-protection decision-making. A PV panel integrated into the heliostat reflecting surface, eliminates cabling and other elements required for a conventional power supply. Communication lines between master control and local control have been replaced by radio-modem. Testing has validated the technical feasibility of the prototype and quantified the real consumption and efficiencies of new elements. The extra costs produced.by the autonomous concepts are compared with the cost of civil work in conventional heliostat field. (Author) 8 refs

  10. A stand-alone demography and landscape structure module for Earth system models

    Science.gov (United States)

    Nieradzik, L. P.; Haverd, V.; Smith, B.; Cook, G. D.; Briggs, P.; Roxburgh, S.; Liedloff, A.; Meyer, C.; Canadell, J.

    2013-12-01

    component of any LSM, represents a significant advance in our ability to use in-situ and remotely sensed observations of biomass and individual level parameters (e.g. crown-size, tree-height, stem diameter) as constraints on the terrestrial carbon cycle. Haverd, V., B. Smith, G. Cook, P. Briggs, L. Nieradzik, S. Roxburgh, A. Liedloff, C. Meyer, and J. G. Canadell, A stand-alone tree demography and landscape structure module for Earth system models, submitted to Geophys. Res. Let., 2013 Wolf, A., P. Ciais, V. Bellassen, N. Delbart, C.B. Field, and J.A. Berry, Forest biomass allometry in global land surface models, Global Biogeochem. Cycles, 25, GB3015, doi:10.1029/2010GB003917, 2011

  11. Optimal sizing of battery storage for stand-alone hybrid (photo-voltaic + diesel) power systems

    Science.gov (United States)

    Shaahid, S. M.; Elhadidy, M. A.

    2005-09-01

    An important element of hybrid photo- voltaic(PV) + diesel sytem is battery storage. Size of battery storage plays a role in optimum operation of the hybrid system. Emphasis needs to be placed on this issue. In this perspective, hourly solar radiation data, for the period 1986 93 recorded at Dhahran, Saudi Arabia, have been analyzed to investigate the optimum size of battery storage capacity for hybrid (PV + diesel) power systems. Various sizing configurations have been simulated. The monthly average daily values of solar global radiation range from 3.61 to 7.96kWh/m2. As a case study, hybrid systems considered in the present analysis consist of 225m2 PV array area (panels/modules) supplemented with battery storage unit and diesel backup generators (to meet the load requirements of a typical residential building with annual electrical energy demand of 35,200kWh). The monthly average energy generated from the aforementioned hybrid system for different scenarios has been presented. More importantly, the study explores the influence of variation of battery storage capacity on hybrid power generation. The results exhibit a trade-off between size of the storage capacity and diesel power to be generated to cope with annual load distribution. Concurrently, the energy to be generated from the diesel generator and the number of operational hours of the diesel system to meet the load demand have been also addressed.The study shows that for optimum operation of diesel system, storage capacity equivalent to 12 18h of maximum monthly average hourly demand need to be used. It has been found that in the absence of battery bank, ˜58% of the load needs to be provided by the diesel system. However, use of 12h of battery storage (autonomy) reduces diesel energy generation by ˜49% and the number of hours of operation of the diesel system get reduced by about ˜82%. The findings of this study can be employed as a tool for sizing of battery storage for PV/diesel systems for other

  12. Control strategy of wind turbine based on permanent magnet synchronous generator and energy storage for stand-alone systems

    DEFF Research Database (Denmark)

    Deng, Fujin; Liu, Dong; Chen, Zhe

    2017-01-01

    This paper investigates a variable speed wind turbine based on permanent magnet synchronous generator and a full-scale power converter in a stand-alone system. An energy storage system(ESS) including battery and fuel cell-electrolyzer combination is connected to the DC link of the full-scale power...... converter through the power electronics interface. Wind is the primary power source of the system, the battery and FC-electrolyzer combination is used as a backup and a long-term storage system to provide or absorb power in the stand-alone system, respectively. In this paper, a control strategy is proposed...... for the operation of this variable speed wind turbine in a stand-alone system, where the generator-side converter and the ESS operate together to meet the demand of the loads. This control strategy is competent for supporting the variation of the loads or wind speed and limiting the DC-link voltage of the full...

  13. Stand-alone photovoltaic applications. Lessons learned

    International Nuclear Information System (INIS)

    Loois, G.; Van Hemert, B.

    1999-02-01

    The IEA Photovoltaic Power Systems Programme (PVPS) is one of the collaborative R and D agreements established within the IEA. The objective of Task III is to promote and facilitate the exchange of information and experiences in the field of PV Systems in Stand-alone and Island Applications (SAPV). The book focuses on the practical experiences gained, and does not aim to provide a complete manual on SAPV. When Task III started its activities in 1993, a collection of 50 'State of the art' projects was published in the book 'Examples of Stand-Alone Photovoltaic Systems'. This publication marked the base line for the work of the task. Now, in 1998, the showcases from each country demonstrate the lessons learned in five years of cooperation. The book consists of two parts. The first part contains eight chapters dealing with a specific aspect of stand-alone PV. The second part introduces 14 national showcase projects in a systematic presentation. Each chapter and showcase can be read independently from the rest of the book. Chapter 2, contributed by The Netherlands, analyses the market for stand-alone PV systems. It gives an overview of the 'traditional' application of stand-alone PV, which is the electrification of remote buildings and which has been addressed in depth in other publications. The focus is on the market niches of service applications that are also interesting for more densely populated areas, e.g. in industrialised countries. The United Kingdom illustrates the economic aspects in Chapter 3. Cost comparisons are made, but more important is the illustration of the non-financial considerations that make PV the preferred choice as a power source for many applications. Switzerland explores in Chapter 4 (financing aspects) different financing mechanisms, and financial policies used to overcome the initial cost barrier. Most of these approaches have been applied in developing countries rather than in the western world. Using various examples from all over the

  14. New Scheme for Seamless Operation for Stand-Alone Power Systems

    Directory of Open Access Journals (Sweden)

    Hyun-Jun Kim

    2016-06-01

    Full Text Available On remote islands photovoltaic (PV panels with battery energy storage systems (BESSs supply electric power to customers in parallel operation with engine generators (EGs to reduce fuel consumption and environmental burden. A BESS operates in voltage control mode when it supplies power to loads alone, while it operates in current control mode when it supplies power to loads in parallel with the EG. This paper proposes a smooth mode change of the BESS from current control to voltage control by using initial value at the output of integral part in the voltage controller, and a smooth mode change from voltage control to current control by tracking the EG output voltage to the BESS output voltage using a phase-locked loop (PLL. The feasibility of the proposed scheme was verified through computer simulations and experiments with a scaled prototype.

  15. Sizing and economic analysis of stand alone photovoltaic system with hydrogen storage

    Science.gov (United States)

    Nordin, N. D.; Rahman, H. A.

    2017-11-01

    This paper proposes a design steps in sizing of standalone photovoltaic system with hydrogen storage using intuitive method. The main advantage of this method is it uses a direct mathematical approach to find system’s size based on daily load consumption and average irradiation data. The keys of system design are to satisfy a pre-determined load requirement and maintain hydrogen storage’s state of charge during low solar irradiation period. To test the effectiveness of the proposed method, a case study is conducted using Kuala Lumpur’s generated meteorological data and rural area’s typical daily load profile of 2.215 kWh. In addition, an economic analysis is performed to appraise the proposed system feasibility. The finding shows that the levelized cost of energy for proposed system is RM 1.98 kWh. However, based on sizing results obtained using a published method with AGM battery as back-up supply, the system cost is lower and more economically viable. The feasibility of PV system with hydrogen storage can be improved if the efficiency of hydrogen storage technologies significantly increases in the future. Hence, a sensitivity analysis is performed to verify the effect of electrolyzer and fuel cell efficiencies towards levelized cost of energy. Efficiencies of electrolyzer and fuel cell available in current market are validated using laboratory’s experimental data. This finding is needed to envisage the applicability of photovoltaic system with hydrogen storage as a future power supply source in Malaysia.

  16. Maximun power point tracker of photovoltaic s panels for stand alone systems

    International Nuclear Information System (INIS)

    Stoll, R; Manno, R

    2005-01-01

    The low energetic efficiency of photovoltaic s panels is known, in addition, due to the use of linear regulators, which dissipate an important bit of the generated energy, the efficiency of the photovoltaic systems is still smaller.Also, the I-V characteristic curve of the photovoltaic modules depends on the solar radiation and the own temperature; consequently, the maximum power point (Wp) changes permanently.In conclusion, to produce electricity with photovoltaic panels is very expensive. However due to preserve the environment this technology is widely used.With the purpose of optimizing the amount of energy produced by the photovoltaic system, two complementary methods are used.One is the Maximum Power Point Tracker (MPPT) system and the other one is the Solar Tracker system.The objective of this project is to reduce that cost increasing the amount of energy produced by the solar panels using a Maximum Power Point Tracker system.This device consists of a DC/DC buck converter of high performance, controlled by a PIC 16F873 micro controller; which carries out the conversions of the analogical signals of the solar array to digital signals (ADC), the PIC output digital signals to the PWM control of the power FET (DAC), and calculates the Duty Cycle (D) for the point of I-V curve where this product becomes maximum.Measurements for different loads and battery charges were made.With the obtained results, the comparisons with a conventional system were made, a greater cession of energy to the load is observed.The main conclusion of this work is: Using a MPPT device to making work the PV module during the greater possible time near the maximum power point, the efficiency of the photovoltaic systems can be increased

  17. Control of a Stand-Alone Variable Speed Wind Energy Supply System

    Directory of Open Access Journals (Sweden)

    Mohamed M. Hamada

    2013-04-01

    Full Text Available This paper presents a simple control strategy for the operation of a variable speed stand-alone wind turbine with a permanent magnet synchronous generator (PMSG. The PMSG is connected to a three phase resistive load through a switch mode rectifier and a voltage source inverter. Control of the generator side converter is used to achieve maximum power extraction from the available wind power. Control of the DC-DC bidirectional buck-boost converter, which is connected between batteries bank and DC-link voltage, is used to maintain the DC-link voltage at a constant value. It is also used to make the batteries bank stores the surplus of wind energy and supplies this energy to the load during a wind power shortage. The load side voltage source inverter uses a relatively complex vector control scheme to control the output load voltage in terms of amplitude and frequency. The control strategy works under wind speed variation as well as with variable load. Extensive simulation results have been performed using MATLAB/SIMULINK.

  18. DOE and AID stand-alone photovoltaic activities

    Science.gov (United States)

    Bifano, W. J.; Ratajczak, A. F.

    The NASA Lewis Research Center (LeRC) is managing stand-alone photovoltaic (PV) system activities sponsored by the U.S. Department of Energy (DOE) and the U.S. Agency for International Development (AID). The DOE project includes village PV power demonstration projects in Gabon (four sites) and the Marshall Islands, PV-powered medical refrigerators in six countries, PV system microprocessor control development activities and PV-hybrid system assessments. The AID project includes a large village system in Tunisia, a water pumping/grain grinding project in Upper Volta, five medical clinics in four countries, PV-powered remote earth station application. These PV activities and summarizes significant findings to data are reviewed.

  19. A Control Approach and Supplementary Controllers for a Stand-Alone System with Predominance of Wind Generation

    Directory of Open Access Journals (Sweden)

    Tiago Lukasievicz

    2018-02-01

    Full Text Available This paper proposes a control approach and supplementary controllers for the operation of a hybrid stand-alone system composed of a wind generation unit and a conventional generation unit based on synchronous generator (CGU. The proposed controllers allow the islanded or isolated operation of small power systems with predominance of wind generation. As an advantage and a paradigm shift, the DC-link voltage of the wind unit is controlled by means of a conventional synchronous generator connected to the AC grid of the system. Two supplementary controllers, added to a diesel generator (DIG and to a DC dump load (DL, are proposed to control the DC-link voltage. The wind generation unit operates in V-f control mode and the DIG operates in PQ control mode, which allows the stand-alone system to operate either in wind-diesel (WD mode or in wind-only (WO mode. The strong influence of the wind turbine speed variations in the DC-link voltage is mitigated by a low-pass filter added to the speed control loop of the wind turbine. The proposed control approach does not require the use battery bank and ultra-capacitor to control the DC-link voltage in wind generation units based on fully rated converter.

  20. Multi-objective optimal planning of the stand-alone microgrid system based on different benefit subjects

    International Nuclear Information System (INIS)

    Guo, Li; Wang, Nan; Lu, Hai; Li, Xialin; Wang, Chengshan

    2016-01-01

    As an important means to realize the energetic complementarity and improve the efficiency of renewable resources, the stand-alone microgrid (SAMG) system gains attention increasingly, especially in islands and remote areas. In this paper, considering the interest conflict of the distribution company and the distributed generation owner, a new multi-objective optimal planning model is formulated for medium voltage SAMG. Besides, to avoid the power constraint of distributed generation (DG) once the over-limit voltage occurs, a novel two-step power dispatch control method including the voltage regulation strategy is proposed, in which the absorption of distributed power by energy storage system (ESS) and the reactive power adjustment though its power control system are used to regulate voltage. The goal of this paper is to search the Pareto-optimal front of the site and capacity of DG as well as the contract price between both parties, and thus can provide effective references for practical planning of SAMG. Considering the high cost of ESS, the investment analysis of ESS is also discussed in the paper. - Highlights: • A multi-objective planning model based on different benefit subjects is proposed. • A two-step power dispatch method including the voltage regulation is proposed. • The economical efficiency of the proposed model is analyzed. • The effective reference for the stand-alone microgrid planning is provided.

  1. Stand-alone XLIF

    DEFF Research Database (Denmark)

    Hansen, E. J.; Simony, A.; Hummel, Stefan

    2015-01-01

    and clinical/radiological results in 22 patients treated with XLIF procedure for DS or degenerative disc disease (DDD). Material and methods: 22 consecutive patients with DS underwent surgery with the XLIF stand-alone procedure, with follow-up of 24 months. Clinical outcome scores were collected. Complications......Introduction: Adult thoracolumbar degeneration is an increasing challenge in the aging population. With age the progressive degeneration of the discs leads to an asymmetric collapse and a thoracolumbar coronal plane deformity, a degenerative scoliosis (DS). Aim: To evaluate the complication rate......-year follow-up, with a 31.8% revision rate. Due to the high revision rate we recommend supplementary posterior instrumentation, to achieve a higher fusion rate. When considering XLIF-stand-alone procedure for DS or DDD without supplemental posterior instrumentation, only single-level disease should...

  2. Feasibility Analysis and Simulation of a Stand-Alone Photovoltaic Energy System for Electricity Generation and Environmental Sustainability – equivalent to 650VA fuel-powered generator - popularly known as I pass my neighbour

    Directory of Open Access Journals (Sweden)

    Vincent Anayochukwu Ani

    2015-09-01

    Full Text Available Photovoltaic (PV power system can be used to replace wholly 650VA generator for electricity generation for household use in Nigeria. This paper presented the feasibility analysis of load data and simulation study of a stand-alone PV power system that produced the electrical needs of a household. This study is based on designing of PV energy system for household use. The patterns of load consumption within the household were studied and suitably modeled for simulation. The simulation study indicates that energy requirements to provide electricity which is equivalent to 650VA generator for household use in Nigeria can be accomplished by 520W solar PV array, 2312 Ah nominal capacity battery, and a 1kW DC/AC inverter. This would be suitable for deployment of 100% clean energy for environmental sustainability and uninterruptable power performance in the household. The results of this research show that, with a low-power consuming appliances, it is possible to meet the entire annual electricity demand of a single household solely through a stand-alone PV energy supply. Installing solar panels by most Nigerian home can significantly reduce home reliance on government power thereby reduce the strain on the current capacity of our power generation infrastructure. A detailed design and description of the system were presented in this paper.

  3. Feasibility Analysis and Simulation of a Stand-Alone Photovoltaic Energy System for Electricity Generation and Environmental Sustainability – Equivalent to 650VA Fuel-Powered Generator – Popularly Known as “I Pass My Neighbour”

    International Nuclear Information System (INIS)

    Ani, Vincent Anayochukwu

    2015-01-01

    Photovoltaic (PV) power system can be used to replace wholly 650VA generator for electricity generation for household use in Nigeria. This paper presented the feasibility analysis of load data and simulation study of a stand-alone PV power system that produced the electrical needs of a household. This study is based on designing of PV energy system for household use. The patterns of load consumption within the household were studied and suitably modeled for simulation. The simulation study indicates that energy requirements to provide electricity, which is equivalent to 650VA generator for household use in Nigeria, can be accomplished by 520 W solar PV array, 2312 Ah nominal capacity battery, and a 1 kW DC/AC inverter. This would be suitable for deployment of 100% clean energy for environmental sustainability and uninterruptable power performance in the household. The results of this research show that, with a low-power consuming appliances, it is possible to meet the entire annual electricity demand of a single household solely through a stand-alone PV energy supply. Installing solar panels by most Nigerian home can significantly reduce home reliance on government power thereby reduce the strain on the current capacity of our power generation infrastructure. A detailed design and description of the system were presented in this paper.

  4. Kajian Pemanfaatan Stand Alone Photovoltaic System Untuk Penerangan Jalan Umum Di Pulau Nusa Penida

    Directory of Open Access Journals (Sweden)

    I.W. Yudi Martha Wiguna

    2012-12-01

    Full Text Available   Nusa Penida merupakan sebuah pulau di tenggara pulau Bali dengan jumlah penduduk 47.448 jiwa. Ketersediaan daya pembangkit PLN di pulau Nusa Penida adalah sebesar 3200 kW. Dengan beban puncak sebesar 2530 kW maka cadangan listrik saat ini hanya sebesar 670 kW. Hal itu menyebabkan krisis listrik sangat terasa bagi masyarakat di daerah terpencil seperti di Pulau Nusa Penida. Saat ini salah satu solusi yang memungkinkan adalah mengembangkan sumber energi terbarukan. Di Pulau Nusa Penida sudah dikembangkan PLTS. Bahkan PLTS di Pulau Nusa Penida dikembangkan juga pada sistem penerangan jalan umum. Pada penelitian ini dilakukan analisa teknis dan biaya untuk mengetahui kelayakan Sistem PJU-TS tersebut. Pada analisa teknis dilakukan pengukuran output tegangan dan arus dari PV Panel ke Charger Controller, dari Charger Controller ke baterai dan ke beban. Analisa teknis menghasilkan bahwa penyebab kerusakan baterai karena kapasitas pembangkitan tidak sebanding dengan kebutuhan kapasitas beban PJU-TS. Dengan kapasitas baterai yang terus kecil akan menyebabkan kerusakan pada baterai. Selain itu karena usia baterai yang sudah lama. Analisa biaya dilakukan dengan 3 skenario dengan tingkat IRR yang ingin dicapai sebesar 10, 11, dan 12 %. Dihasilkan harga jual yang pantas untuk energi listrik PJU-TS Nusa Penida berkisar antara Rp.29.194,00 s/d Rp.31.585,00 per kWh.

  5. Integration of hydrogen energy technologies in stand-alone power systems analysis of the current potential for applications

    International Nuclear Information System (INIS)

    Zoulias, E.I.; Lymberopoulos, N.; Tsoutsos, T.; Glockner, R.; Mydske, H.J.; Vosseler, I.; Gavalda, O.; Taylor, P.

    2006-01-01

    The European study entitled: 'Market Potential Analysis for Introduction of Hydrogen Energy Technology in Stand-Alone Power Systems (H-SAPS)' aimed to establish a broad understanding of the market potential for H-SAPS and provide a basis for promoting in wide scale new technological applications. The scope of the study was limited to small and medium installations, up to a few hundred kW power rating and based on RE as the primary energy source. The potential for hydrogen technology in SAPS was investigated through an assessment of the technical potential for hydrogen, the market analysis and the evaluation of external factors. The results are mostly directed towards action by governments and the research community but also industry involvement is identified. The results include targeted market research, establishment of individual cost targets, regulatory changes to facilitate alternative grid solutions, information and capacity building, focused technology research and bridging the technology gaps. (author)

  6. Mitigation of large power spills by an energy storage device in a stand alone energy system

    NARCIS (Netherlands)

    D. Bhaumik (Debarati); D.T. Crommelin (Daan); A.P. Zwart (Bert)

    2018-01-01

    textabstractThe unpredictable nature of wind energy makes its integration to the electric grid highly challenging. However, these challenges can be addressed by incorporating storage devices (batteries) in the system. We perform an overall assessment of a single domestic power system with a wind

  7. Analysis of a small wind-hydrogen stand-alone hybrid energy system

    International Nuclear Information System (INIS)

    Khan, M.J.; Iqbal, M.T.

    2009-01-01

    In this article, detailed modeling, simulation, and analysis of an isolated wind-hydrogen hybrid energy system is presented. Dynamic nonlinear models of all the major subsystems are developed based on sets of empirical and physical relationships. The performance of the integrated hybrid energy system is then analyzed through digital simulation. Design of dynamic controllers and supervisory control schemes are also presented. Expected behaviors during sudden load variation, wind speed change and hydrogen pressure drop are observed under both stochastic and step-variation conditions. MATLAB-Simulink TM is employed for dynamic system modeling. This exercise, in essence, outlines a process of wind-hydrogen off-grid system control synthesis and performance evaluation. Finally, results of the analysis are summarized, limitations of the simulation study are identified, and scope for future work is indicated.

  8. Transforming stand-alone expert system into a community of cooperating agents

    CERN Document Server

    Jennings, N R; Aarnts, R P; Fuchs, J; Skarek, Paul

    1993-01-01

    Distributed Artificial Intelligence (DAI) systems in which multiple problem solving agents cooperate to achieve a common objective is a rapidly emerging and promising technology. However, as yet, there have been relatively few reported cases of such systems being employed to tackle real-world problems in realistic domains. One of the reasons for this is that DAI researchers have given virtually no consideration to the process of incorporating pre-existing systems into a community of cooperating agents. Yet reuse is a primary consideration for any organisation with a large software base. To redress the balance, this paper reports on an experiment undertaken at the CERN laboratories, in which two pre-existing and standalone expert systems for diagnosing faults in a particle accelerator were transformed into a community of cooperating agents. The experiences and insights gained during this process provide a valuable first step towards satisfying the needs of potential users of DAI technology - identifying the ty...

  9. Comparison of two stand-alone CADe systems at multiple operating points

    Science.gov (United States)

    Sahiner, Berkman; Chen, Weijie; Pezeshk, Aria; Petrick, Nicholas

    2015-03-01

    Computer-aided detection (CADe) systems are typically designed to work at a given operating point: The device displays a mark if and only if the level of suspiciousness of a region of interest is above a fixed threshold. To compare the standalone performances of two systems, one approach is to select the parameters of the systems to yield a target false-positive rate that defines the operating point, and to compare the sensitivities at that operating point. Increasingly, CADe developers offer multiple operating points, which necessitates the comparison of two CADe systems involving multiple comparisons. To control the Type I error, multiple-comparison correction is needed for keeping the family-wise error rate (FWER) less than a given alpha-level. The sensitivities of a single modality at different operating points are correlated. In addition, the sensitivities of the two modalities at the same or different operating points are also likely to be correlated. It has been shown in the literature that when test statistics are correlated, well-known methods for controlling the FWER are conservative. In this study, we compared the FWER and power of three methods, namely the Bonferroni, step-up, and adjusted step-up methods in comparing the sensitivities of two CADe systems at multiple operating points, where the adjusted step-up method uses the estimated correlations. Our results indicate that the adjusted step-up method has a substantial advantage over other the two methods both in terms of the FWER and power.

  10. Constrained control framework for a stand-alone hybrid (Stirling engine)/supercapacitor power generation system

    International Nuclear Information System (INIS)

    Alamir, M.; Rahmani, M.A.; Gualino, D.

    2014-01-01

    Highlights: • A complete state feedback controller for the voltage conditioning stage of a hybrid power plant is proposed. • The controller explicitly handles the state and controller constraints. • The developed control methodology can be applied to various power electronics architectures. - Abstract: In this paper, a complete control architecture is proposed for the voltage conditioning stage of a hybrid power generation system composed of a Stirling engine coupled with a supercapacitor. Such a solar energy-based generation system aims at providing electricity to off-grid regions. The novelty of the proposed architecture is that it completely handles constraints on all the state variables of the electric stage while providing near to optimal performances in terms of settling time. The derivation of the control law enables a deep understanding of the main issues involved in the success of the closed-loop control. Moreover, the resulting feedback laws are real-time compatible and are given in a complete explicit form

  11. Optimal Sizing of a Stand-Alone Hybrid Power System Based on Battery/Hydrogen with an Improved Ant Colony Optimization

    Directory of Open Access Journals (Sweden)

    Weiqiang Dong

    2016-09-01

    Full Text Available A distributed power system with renewable energy sources is very popular in recent years due to the rapid depletion of conventional sources of energy. Reasonable sizing for such power systems could improve the power supply reliability and reduce the annual system cost. The goal of this work is to optimize the size of a stand-alone hybrid photovoltaic (PV/wind turbine (WT/battery (B/hydrogen system (a hybrid system based on battery and hydrogen (HS-BH for reliable and economic supply. Two objectives that take the minimum annual system cost and maximum system reliability described as the loss of power supply probability (LPSP have been addressed for sizing HS-BH from a more comprehensive perspective, considering the basic demand of load, the profit from hydrogen, which is produced by HS-BH, and an effective energy storage strategy. An improved ant colony optimization (ACO algorithm has been presented to solve the sizing problem of HS-BH. Finally, a simulation experiment has been done to demonstrate the developed results, in which some comparisons have been done to emphasize the advantage of HS-BH with the aid of data from an island of Zhejiang, China.

  12. Daily operation optimisation of hybrid stand-alone system by model predictive control considering ageing model

    International Nuclear Information System (INIS)

    Dufo-López, Rodolfo; Fernández-Jiménez, L. Alfredo; Ramírez-Rosado, Ignacio J.; Artal-Sevil, J. Sergio; Domínguez-Navarro, José A.; Bernal-Agustín, José L.

    2017-01-01

    Highlights: • Method for optimising the daily operation of photovoltaic-wind-diesel-battery systems. • Weather forecasts of hourly wind speed, irradiation, temperature and load are used. • Each day five control variables are optimised for the control of the system. • Operating cost includes real ageing of the batteries and the diesel generator. • Results show that the optimal control strategy used for each day led to cost savings. - Abstract: This article presents a method for optimising the daily operation (minimising the total operating cost) of a hybrid photovoltaic-wind-diesel-battery system using model predictive control. The model uses actual weather forecasts of hourly values of wind speed, irradiation, temperature and load. Five control variables are optimised, and thus their optimal set points values determine the optimal control strategy for each day. This involves the use of an accurate model for estimating the degradation of the batteries by considering the capacity loss due to corrosion and degradation. The model considers the extra costs of maintaining and replacing the diesel generator due to running out of its optimal conditions. The optimisation is carried out by means of genetic algorithms. An example of application compares the total operating cost obtained using the optimal control strategy for each day with the cost of using the optimal control strategy found for the whole year, obtaining savings of up to 7.8%. Also the comparison with the cost of using the “load following” control strategy is analysed, obtaining savings of up to 37.7%.

  13. Automation infrastructure and operation control strategy in a stand-alone power system based on renewable energy sources

    Science.gov (United States)

    Ziogou, Chrysovalantou; Ipsakis, Dimitris; Elmasides, Costas; Stergiopoulos, Fotis; Papadopoulou, Simira; Seferlis, Panos; Voutetakis, Spyros

    The design of the automation system and the implemented operation control strategy in a stand-alone power system in Greece are fully analyzed in the present study. A photovoltaic array and three wind generators serve as the system main power sources and meet a predefined load demand. A lead-acid accumulator is used to compensate the inherent power fluctuations (excess or shortage) and to regulate the overall system operation, based on a developed power management strategy. Hydrogen is produced by using system excess power in a proton exchange membrane (PEM) electrolyzer and is further stored in pressurized cylinders for subsequent use in a PEM fuel cell in cases of power shortage. A diesel generator complements the integrated system and is employed only in emergency cases, such as subsystems failure. The performance of the automatic control system is evaluated through the real-time operation of the power system where data from the various subsystems are recorded and analyzed using a supervised data acquisition unit. Various network protocols were used to integrate the system devices into one central control system managing in this way to compensate for the differences between chemical and electrical subunits. One of the main advantages is the ability of process monitoring from distance where users can perform changes to system principal variables. Furthermore, the performance of the implemented power management strategy is evaluated through simulated scenarios by including a case study analysis on system abilities to meet higher than expected electrical load demands.

  14. Investigation of heating and cooling in a stand-alone high temperature PEM fuel cell system

    International Nuclear Information System (INIS)

    Zhang, Caizhi; Yu, Tao; Yi, Jun; Liu, Zhitao; Raj, Kamal Abdul Rasheedj; Xia, Lingchao; Tu, Zhengkai; Chan, Siew Hwa

    2016-01-01

    Highlights: • Heating-up and cooling-down processes of HT-PEMFC are the mainly interested topics. • Dynamic behaviours, power and energy demand of the heating and cooling was studied. • Hybrid system based on LiFeYPO 4 battery for heating and cooling is built and tested. • The concept of combining different heating sources together is recommended. - Abstract: One key issue pertaining to the cold-start of High temperature PEM fuel cell (HT-PEMFC) is the requirement of high amount of thermal energy for heating up the stack to a temperature of 120 °C or above before it can generate electricity. Furthermore, cooling down the stack to a certain temperature (e.g. 50 °C) is necessary before stopping. In this study, the dynamic behaviours, power and energy demand of a 6 kW liquid cooled HT-PEMFC stack during heating-up, operation and cooling-down were investigated experimentally. The dynamic behaviours of fuel cell under heating-up and cooling-down processes are the mainly interested topics. Then a hybridisation of HT-PEMFC with Li-ion battery to demonstrate the synergistic effect on dynamic behaviour was conducted and validated for its feasibility. At last, the concept of combining different heating sources together is analysed to reduce the heating time of the HT-PEMFC as well.

  15. Single-crate stand-alone CAMAC control system for a negative ion source test facility

    International Nuclear Information System (INIS)

    Juras, R.C.; Ziegler, N.F.

    1979-01-01

    A single-crate CAMAC system was configured to control a negative ion source development facility at ORNL and control software was written for the crate microcomputer. The software uses inputs from a touch panel and a shaft encoder to control the various operating parameters of the test facility and uses the touch panel to display the operating status. Communication to and from the equipment at ion source potential is accomplished over optical fibers from an ORNL-built CAMAC module. A receiver at ion source potential stores the transmitted data and some of these stored values are then used to control discrete parameters of the ion source (i.e., power supply on or off). Other stored values are sent to a multiplexed digital-to-analog converter to provide analog control signals. A transmitter at ion source potential transmits discrete status information and several channels of analog data from an analog-to-digital converter back to the ground-potential receiver where it is stored to be read and displayed by the software

  16. A Voltage and Frequency Control Strategy for Stand-Alone Full Converter Wind Energy Conversion Systems

    Directory of Open Access Journals (Sweden)

    Andrés Peña Asensio

    2018-02-01

    Full Text Available This paper addresses the design and analysis of a voltage and frequency control (VFC strategy for full converter (FC-based wind energy conversion systems (WECSs and its applicability for the supply of an isolated load. When supplying an isolated load, the role of the back-to-back converters in the FC must change with respect to a grid-connected application. Voltage and frequency are established by the FC line side converter (LSC, while the generator side converter (GSC is responsible for maintaining constant voltage in the DC link. Thus, the roles of the converters in the WECS are inverted. Under such control strategies, the LSC will automatically supply the load power and hence, in order to maintain a stable operation of the WECS, the wind turbine (WT power must also be controlled in a load-following strategy. The proposed VFC is fully modelled and a stability analysis is performed. Then, the operation of the WECS under the proposed VFC is simulated and tested on a real-time test bench, demonstrating the performance of the VFC for the isolated operation of the WECS.

  17. A new technique based on Artificial Bee Colony Algorithm for optimal sizing of stand-alone photovoltaic system

    Directory of Open Access Journals (Sweden)

    Ahmed F. Mohamed

    2014-05-01

    Full Text Available One of the most recent optimization techniques applied to the optimal design of photovoltaic system to supply an isolated load demand is the Artificial Bee Colony Algorithm (ABC. The proposed methodology is applied to optimize the cost of the PV system including photovoltaic, a battery bank, a battery charger controller, and inverter. Two objective functions are proposed: the first one is the PV module output power which is to be maximized and the second one is the life cycle cost (LCC which is to be minimized. The analysis is performed based on measured solar radiation and ambient temperature measured at Helwan city, Egypt. A comparison between ABC algorithm and Genetic Algorithm (GA optimal results is done. Another location is selected which is Zagazig city to check the validity of ABC algorithm in any location. The ABC is more optimal than GA. The results encouraged the use of the PV systems to electrify the rural sites of Egypt.

  18. A new technique based on Artificial Bee Colony Algorithm for optimal sizing of stand-alone photovoltaic system.

    Science.gov (United States)

    Mohamed, Ahmed F; Elarini, Mahdi M; Othman, Ahmed M

    2014-05-01

    One of the most recent optimization techniques applied to the optimal design of photovoltaic system to supply an isolated load demand is the Artificial Bee Colony Algorithm (ABC). The proposed methodology is applied to optimize the cost of the PV system including photovoltaic, a battery bank, a battery charger controller, and inverter. Two objective functions are proposed: the first one is the PV module output power which is to be maximized and the second one is the life cycle cost (LCC) which is to be minimized. The analysis is performed based on measured solar radiation and ambient temperature measured at Helwan city, Egypt. A comparison between ABC algorithm and Genetic Algorithm (GA) optimal results is done. Another location is selected which is Zagazig city to check the validity of ABC algorithm in any location. The ABC is more optimal than GA. The results encouraged the use of the PV systems to electrify the rural sites of Egypt.

  19. Techno-economic analysis of stand-alone photovoltaic/wind/battery/hydrogen systems for very small-scale applications

    Directory of Open Access Journals (Sweden)

    Stojković Saša M.

    2016-01-01

    Full Text Available The paper presents the results of a technical and economic analysis of three stand-alone hybrid power systems based on renewable energy sources which supply a specific group of low-power consumers. This particular case includes measuring sensors and obstacle lights on a meteorological mast for wind measurements requiring an uninterrupted power supply in cold climate conditions. Although these low-power (100 W measuring sensors and obstacle lights use little energy, their energy consumption is not the same as the available solar energy obtained on a daily or seasonal basis. In the paper, complementarity of renewable energy sources was analysed, as well as one of short-term lead-acid battery-based storage and seasonal, hydrogen-based (electrolyser, H2 tank, and fuel cells storage. These relatively complex power systems were proposed earlier for high-power consumers only, while this study specifically highlights the role of the hydrogen system for supplying low-power consumers. The analysis employed a numerical simulation method using the HOMER software tool. The results of the analysis suggest that solar and wind-solar systems, which involve meteorological conditions as referred to in this paper, include a relatively large number of lead-acid batteries. Additionally, the analysis suggests that the use of hydrogen power systems for supplying low power-consumers is entirely justifiable, as it significantly reduces the number of batteries (two at minimum in this particular case. It was shown that the increase in costs induced by the hydrogen system is acceptable.

  20. Stand-alone Inverter: Reviews, Models and Tests the exist system in Term of the Power Quality, and Suggestions to Design it

    Directory of Open Access Journals (Sweden)

    Ali Algaddafi

    2016-10-01

    Full Text Available Developments in power electronics have enabled the widespread application of Pulse Width Modulation (PWM inverters, notably for obtaining electricity from renewable systems. This paper critical review the previous studies in designing stand-alone inverter and modelling the inverter with two control loops to improve and provide a high-quality power of a stand-alone inverter. Multi-loop control techniques for a stand-alone inverter are utilised as the first loop is a capacitor current control to provide active damping and improve transient and steady state inverter performance. The capacitor current control is cheaper than inductor current control, where a small current sensing resistor is used. The second loop is the output voltage control that is used to improve the system performance and also control the output voltage. The power quality of the off-grid system is measured experimentally and compared with the grid power, showing power quality of off-grid system to be better than that of the grid. The suggestions and key findings to design the stand-alone inverter are given based in the reviewing of previous publications and from the literature’s point of view.

  1. PVSOFT99 - Photovoltaic (PV) System Sizing And Simulation Software

    African Journals Online (AJOL)

    A computer program (PVSOFT99) has been developed for sizing and simulation of stand-alone photovoltaic (PV) systems. Two distinct PV sizing algorithms, one based on the worst case and the other on the reliability concept, have been incorporated in the program. The reliability concept is generalized in that variation of ...

  2. Modeling and simulation of stand-alone hybrid power system with fuzzy MPPT for remote load application

    Directory of Open Access Journals (Sweden)

    Bogaraj T.

    2015-09-01

    Full Text Available Many parts of remote locations in the world are not electrified even in this Advanced Technology Era. To provide electricity in such remote places renewable hybrid energy systems are very much suitable. In this paper PV/Wind/Battery Hybrid Power System (HPS is considered to provide an economical and sustainable power to a remote load. HPS can supply the maximum power to the load at a particular operating point which is generally called as Maximum Power Point (MPP. Fuzzy Logic based MPPT (FLMPPT control method has been implemented for both Solar and Wind Power Systems. FLMPPT control technique is implemented to generate the optimal reference voltage for the first stage of DC-DC Boost converter in both the PV and Wind energy system. The HPS is tested with variable solar irradiation, temperature, and wind speed. The FLMPPT method is compared with P&O MPPT method. The proposed method provides a good maximum power operation of the hybrid system at all operating conditions. In order to combine both sources, the DC bus voltage is made constant by employing PI Controllers for the second stage of DC-DC Buck-Boost converter in both Solar and Wind Power Systems. Battery Bank is used to store excess power from Renewable Energy Sources (RES and to provide continuous power to load when the RES power is less than load power. A SPWM inverter is designed to convert DC power into AC to supply three phase load. An LC filter is also used at the output of inverter to get sinusoidal current from the PWM inverter. The entire system was modeled and simulated in Matlab/Simulink Environment. The results presented show the validation of the HPS design.

  3. A maximum power point tracking scheme for a 1kw stand-alone ...

    African Journals Online (AJOL)

    A maximum power point tracking scheme for a 1kw stand-alone solar energy based power supply. ... This paper elucidates one of the tracking schemes for a photovoltaic (PV) systems using Cuk converter operating in discontinuous inductor current mode (DICM) as an interface. A method for efficiently maximizing the output ...

  4. 100 KW pv system design

    International Nuclear Information System (INIS)

    Khan, N.; Abas, N.

    2010-01-01

    This paper reports the design of a 100kw photovolatic (PV) system for 10,000 ft/sup 2/ roof building. It explain the necessary design steps for medium power PV system specifications of associated accessories for large size building solar electrification. A comparison between various solar technologies and their ancillary anchors is provided to guide the young electric power and renewable energy engineers. It is to prove that hybrid photovolatic thermal (PVT) technology is more efficient than simple photovolatic (PV), photovolatic concentrator (PVC) or stand-alone solar thermal heating systems. We have been using fossil fuels from 1859 to 2009. Oil triggered population growth rate which in turn increased energy demand for iil. A 200 years close loop positive feedback has amplified oil production rate for few thousand barrels to 86-87 billion barrels. Today the world population is burning oil at rate of 1000 barrels/sec. The oil reserves are likely to end by 2050 (worst case) or 2100 (best case). At 1.7% growth rate the current global population might double to 12 billion barrels and electric power demand will increase from current 15 TW to TW. Unfortunately oil reserves would be breathing last and global warning would be at its climax. To cope with upcoming power, water water and energy cataclysms, it is more than essential to go for sustainable and renewable and renewable energy education and lifestyles. I hope this design venture will create interest among power and energy students, engineers and professional engine. (author)

  5. Sensor System for Long-term Recording of Photovoltaic (PV) IV-curves

    DEFF Research Database (Denmark)

    Paasch, Kasper; Nymand, Morten; Haase, Frerk

    The purpose of this paper is to present a recording system for long-term investigation of PV panel dynamics under partial shading conditions. The system is intended to be a low-cost system deployable for stand-alone field use and long-term data recording at PV-plants. Passing clouds will affect...

  6. Efficient estimator of probabilities of large power spills in an stand-alone system with wind generation and storage

    NARCIS (Netherlands)

    D. Bhaumik (Debarati); D.T. Crommelin (Daan); A.P. Zwart (Bert)

    2016-01-01

    textabstractThe challenges of integrating unpredictable wind energy into a power system can be alleviated using energy storage devices. We assessed a single domestic energy system with a wind turbine and a battery. We investigated the best operation mode of the battery such that the occurrence of

  7. Analysis of the impact of batteries behaviour on stand-alone photovoltaic systems; Analise do impacto do comportamento de baterias em sistemas fotovoltaicos autonomos

    Energy Technology Data Exchange (ETDEWEB)

    Vera, Luis Horacio

    2009-08-15

    Stand-alone photovoltaic systems are a suitable alternative for rural electrification. However, there are still problems to be solved, mainly related to the system design and the technical quality of the equipment and facilities, which impacts the systems reliability. To determine the factors that affect the reliability of these systems it were studied the most common configurations and associated failures. The Laboratory experimental research, together with an extensive literature review, show the basic technical problems that occur to each of the elements of the installation and the dependence between them. These studies have shown that the storage the system, considering system reliability and economy, is the weakest element due to the decrease of their storage capacity. This led to consider the storage systems as the focus of this study and, through the analysis of their behavior, to develop a procedure to size systems with high reliability, lower cost and appropriate configuration. The impact of batteries on the technical reliability and economic viability of photovoltaic systems is determined. It was achieved through experimental testing and the development and adjustment of mathematical models. These models were implemented to preexisting software called PVSize. The improved software allows the calculation of different configurations of systems and to determine the loss of load probability and the figures of merit associated to the chosen economic-financial project. On this work was installed a photovoltaic system and was developed a battery testing system. The values measured in these systems allow to verify the mathematical models that describe the behavior of each device and characterize the components of the system. Experimental analysis of the behavior of a bank of batteries along a year showed that the connection of batteries in parallel accelerates the batteries degradation process, and this degradation has differentiated impact on the loss of

  8. Fuel cells, batteries and super-capacitors stand-alone power systems management using optimal/flatness based-control

    Science.gov (United States)

    Benaouadj, M.; Aboubou, A.; Ayad, M. Y.; Bahri, M.; Boucetta, A.

    2016-07-01

    In this work, an optimal control (under constraints) based on the Pontryagin's maximum principle is used to optimally manage energy flows in a basic PEM (Proton Exchange Membrane) fuel cells system associated to lithium-ion batteries and supercapacitors through a common DC bus having a voltage to stabilize using the differential flatness approach. The adaptation of voltage levels between different sources and load is ensured by use of three DC-DC converters, one boost connected to the PEM fuel cells, while the two others are buck/boost and connected to the lithiumion batteries and supercapacitors. The aim of this paper is to develop an energy management strategy that is able to satisfy the following objectives: - Impose the power requested by a habitat (representing the load) according to a proposed daily consumption profile, - Keep fuel cells working at optimal power delivery conditions, - Maintain constant voltage across the common DC bus, - Stabilize the batteries voltage and stored quantity of charge at desired values given by the optimal control.Results obtained under MATLAB/Simulink environment prove that the cited objectives are satisfied, validating then, effectiveness and complementarity between the optimal and flatness concepts proposed for energy management. Note that this study is currently in experimentally validation within MSE Laboratory.

  9. Fuel cells, batteries and super-capacitors stand-alone power systems management using optimal/flatness based-control

    International Nuclear Information System (INIS)

    Benaouadj, M.; Aboubou, A.; Bahri, M.; Boucetta, A.; Ayad, M. Y.

    2016-01-01

    In this work, an optimal control (under constraints) based on the Pontryagin’s maximum principle is used to optimally manage energy flows in a basic PEM (Proton Exchange Membrane) fuel cells system associated to lithium-ion batteries and supercapacitors through a common DC bus having a voltage to stabilize using the differential flatness approach. The adaptation of voltage levels between different sources and load is ensured by use of three DC-DC converters, one boost connected to the PEM fuel cells, while the two others are buck/boost and connected to the lithiumion batteries and supercapacitors. The aim of this paper is to develop an energy management strategy that is able to satisfy the following objectives: Impose the power requested by a habitat (representing the load) according to a proposed daily consumption profile, Keep fuel cells working at optimal power delivery conditions, Maintain constant voltage across the common DC bus, Stabilize the batteries voltage and stored quantity of charge at desired values given by the optimal control. Results obtained under MATLAB/Simulink environment prove that the cited objectives are satisfied, validating then, effectiveness and complementarity between the optimal and flatness concepts proposed for energy management. Note that this study is currently in experimentally validation within MSE Laboratory.

  10. Fuel cells, batteries and super-capacitors stand-alone power systems management using optimal/flatness based-control

    Energy Technology Data Exchange (ETDEWEB)

    Benaouadj, M.; Aboubou, A.; Bahri, M.; Boucetta, A. [MSE Laboratory, Mohamed khiderBiskra University (Algeria); Ayad, M. Y., E-mail: ayadmy@gmail.com [R& D, Industrial Hybrid Vehicle Applications (France)

    2016-07-25

    In this work, an optimal control (under constraints) based on the Pontryagin’s maximum principle is used to optimally manage energy flows in a basic PEM (Proton Exchange Membrane) fuel cells system associated to lithium-ion batteries and supercapacitors through a common DC bus having a voltage to stabilize using the differential flatness approach. The adaptation of voltage levels between different sources and load is ensured by use of three DC-DC converters, one boost connected to the PEM fuel cells, while the two others are buck/boost and connected to the lithiumion batteries and supercapacitors. The aim of this paper is to develop an energy management strategy that is able to satisfy the following objectives: Impose the power requested by a habitat (representing the load) according to a proposed daily consumption profile, Keep fuel cells working at optimal power delivery conditions, Maintain constant voltage across the common DC bus, Stabilize the batteries voltage and stored quantity of charge at desired values given by the optimal control. Results obtained under MATLAB/Simulink environment prove that the cited objectives are satisfied, validating then, effectiveness and complementarity between the optimal and flatness concepts proposed for energy management. Note that this study is currently in experimentally validation within MSE Laboratory.

  11. Application of the Extension Taguchi Method to Optimal Capability Planning of a Stand-alone Power System

    Directory of Open Access Journals (Sweden)

    Meng-Hui Wang

    2016-03-01

    Full Text Available An Extension Taguchi Method (ETM is proposed on the optimized allocation of equipment capacity for solar cell power generation, wind power generation, full cells, electrolyzer and hydrogen tanks. The ETM is based on the domain knowledge containing the product specifications and allocation levels provided by suppliers and design factors since most of the renewable energy equipment available in the market comes with a specific capacity. A proper orthogonal array is used to collect 18 sets of simulation responses. The extension theory is introduced to determine the correlation function, and factor effects are used to identify the optimized capacity allocation. The hours of power shortage are simulated using Matlab for all capacity allocations at the lowest establishment cost and the optimized capacity allocation of loss of load probability (LOLP. Finally, the extension theory, extension AHP theory, ETM and Analytic Hierarchy Process (AHP are used to determine the optimized capacity allocation of the system. Results are compared for the above four optimization simulation methods and verify that the proposed ETM surpasses the others on achieving the optimized capacity allocation.

  12. Optimal/flatness based-control of stand-alone power systems using fuel cells, batteries and supercapacitors

    Directory of Open Access Journals (Sweden)

    Mahdi Benaouadj

    2017-03-01

    Full Text Available In this work, an optimal control (under constraints based on the Pontryagin’s maximum principle is used to optimally manage energy flows in a basic PEM (Proton Exchange Membrane fuel cells system associated to lithium-ion batteries and supercapacitors through a common DC bus having a voltage to stabilize using the differential flatness approach. The adaptation of voltage levels between different sources and load is ensured by use of three DCDC converters, one boost connected to the PEM fuel cells, while the two others are buck/boost and connected to the lithium-ion batteries and supercapacitors. The aim of this paper is to develop an energy management strategy that is able to satisfy the following objectives: - Impose the power requested by a habitat (representing the load according to a proposed daily consumption profile, - Keep fuel cells working at optimal power delivery conditions, - Maintain constant voltage across the common DC bus, - Stabilize the batteries voltage and stored quantity of charge at desired values given by the optimal control. Results obtained under MATLAB/Simulink environment prove that the cited objectives are satisfied, validating then, effectiveness and complementarity between the optimal and flatness concepts proposed for energy management. Note that this study is currently in experimentally validation within MSE Laboratory.

  13. A stand-alone tree demography and landscape structure module for Earth system models: integration with global forest data

    Science.gov (United States)

    Haverd, V.; Smith, B.; Nieradzik, L. P.; Briggs, P. R.

    2014-02-01

    Poorly constrained rates of biomass turnover are a key limitation of Earth system models (ESM). In light of this, we recently proposed a new approach encoded in a model called Populations-Order-Physiology (POP), for the simulation of woody ecosystem stand dynamics, demography and disturbance-mediated heterogeneity. POP is suitable for continental to global applications and designed for coupling to the terrestrial ecosystem component of any ESM. POP bridges the gap between first generation Dynamic Vegetation Models (DVMs) with simple large-area parameterisations of woody biomass (typically used in current ESMs) and complex second generation DVMs, that explicitly simulate demographic processes and landscape heterogeneity of forests. The key simplification in the POP approach, compared with second-generation DVMs, is to compute physiological processes such as assimilation at grid-scale (with CABLE or a similar land surface model), but to partition the grid-scale biomass increment among age classes defined at sub grid-scale, each subject to its own dynamics. POP was successfully demonstrated along a savanna transect in northern Australia, replicating the effects of strong rainfall and fire disturbance gradients on observed stand productivity and structure. Here, we extend the application of POP to a range of forest types around the globe, employing paired observations of stem biomass and density from forest inventory data to calibrate model parameters governing stand demography and biomass evolution. The calibrated POP model is then coupled to the CABLE land surface model and the combined model (CABLE-POP) is evaluated against leaf-stem allometry observations from forest stands ranging in age from 3 to 200 yr. Results indicate that simulated biomass pools conform well with observed allometry. We conclude that POP represents a preferable alternative to large-area parameterisations of woody biomass turnover, typically used in current ESMs.

  14. The Stand-alone Heliostat; El Heliostato Autonomo

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Navajas, G.; Egea Gea, A. [Ciemat. Madrid (Spain)

    2000-07-01

    The first Autonomous Heliostat has been developed by CIEMAT at PSA facilities in Almeria. This heliostat is an innovative approach to reducing the civil engineering work costs in heliostat fields of central tower plants. Channels, cables and other electric elements have been eliminated in the new heliostat. Thus, one 70-m''2, classical T glass/metal heliostat has been adapted to include all the new stand-alone concept components. A PV system is able to drive two sun-tracking DC motors between 5 and 24 Vdc, 0 and 15A. The heliostat communicates with the control room 400-m away by using a radio-modern working at 9600 baud. An anemometer, a wind switcher, light and ambient temperature sensors have been installed on the heliostat for self-protection decision-making. A PV panel integrated into the heliostat reflecting surface, eliminates cabling and other elements required for a conventional power supply. Communication lines between master control and local control have been replaced by radio-modern. Testing has validated the technical feasibility of the prototype and quantified the real consumption and efficiencies of new elements. The extra costs produced by the autonomous concepts are compared with the cost of civil work in conventional heliostat field. (Author) 8 refs.

  15. Parallel experimental study of a novel super-thin thermal absorber based photovoltaic/thermal (PV/T system against conventional photovoltaic (PV system

    Directory of Open Access Journals (Sweden)

    Peng Xu

    2015-11-01

    Full Text Available Photovoltaic (PV semiconductor degrades in performance due to temperature rise. A super thin-conductive thermal absorber is therefore developed to regulate the PV working temperature by retrofitting the existing PV panel into the photovoltaic/thermal (PV/T panel. This article presented the parallel comparative investigation of the two different systems through both laboratory and field experiments. The laboratory evaluation consisted of one PV panel and one PV/T panel respectively while the overall field system involved 15 stand-alone PV panels and 15 retrofitted PV/T panels. The laboratory testing results demonstrated the PV/T panel could achieve the electrical efficiency of about 16.8% (relatively 5% improvement comparing with the stand-alone PV panel, and yield an extra amount of heat with thermal efficiency of nearly 65%. The field testing results indicated that the hybrid PV/T panel could enhance the electrical return of PV panels by nearly 3.5%, and increase the overall energy output by nearly 324.3%. Further opportunities and challenges were then discussed from aspects of different PV/T stakeholders to accelerate the development. It is expected that such technology could become a significant solution to yield more electricity, offset heating load freely and reduce carbon footprint in contemporary energy environment.

  16. The Impact of Course Delivery Systems on Student Achievement and Sense of Community: A Comparison of Learning Community versus Stand-Alone Classroom Settings in an Open-Enrollment Inner City Public Community College

    Science.gov (United States)

    Bandyopadhyay, Pamela

    2010-01-01

    This study examined the effects of two types of course delivery systems (learning community classroom environments versus stand-alone classroom environments) on the achievement of students who were simultaneously enrolled in remedial and college-level social science courses at an inner city open-enrollment public community college. This study was…

  17. Basic Stand Alone Medicare Outpatient Procedures PUF

    Data.gov (United States)

    U.S. Department of Health & Human Services — This release contains the Basic Stand Alone (BSA) Outpatient Procedures Public Use Files (PUF) with information from Medicare outpatient claims. The CMS BSA...

  18. Basic Stand Alone Medicare Hospice Beneficiary PUF

    Data.gov (United States)

    U.S. Department of Health & Human Services — This release contains the Basic Stand Alone (BSA) Hospice Beneficiary Public Use Files (PUF) with information from Medicare hospice claims. The CMS BSA Hospice...

  19. Basic Stand Alone Carrier Line Items PUF

    Data.gov (United States)

    U.S. Department of Health & Human Services — This release contains the Basic Stand Alone (BSA) Carrier Line Items Public Use Files (PUF) with information from Medicare Carrier claims. The CMS BSA Carrier Line...

  20. Basic Stand Alone Medicare Inpatient Claims PUF

    Data.gov (United States)

    U.S. Department of Health & Human Services — This release contains the Basic Stand Alone (BSA) Inpatient Public Use Files (PUF) named CMS 2008 BSA Inpatient Claims PUF with information from 2008 Medicare...

  1. Effect of State Feedback Coupling and System Delays on the Transient Performance of Stand-Alone VSI with LC Output Filter

    DEFF Research Database (Denmark)

    Federico, de Bosio; de Sousa Ribeiro, Luiz Antonio; Freijedo Fernandez, Francisco Daniel

    2016-01-01

    The influence of state feedback coupling in the dynamics performance of power converters for stand-alone microgrids is investigated. Computation and PWM delays are the main factors that limit the achievable bandwidth of current regulators in digital implementations. In particular, the performance...... provided. A proportional resonant voltage controller is designed according to Nyquist criterion taking into account application requirements. For this purpose, a mathematical expression based on root locus analysis is proposed to find the minimum value of the fundamental resonant gain. Experimental tests...

  2. Real time PV manufacturing diagnostic system

    Energy Technology Data Exchange (ETDEWEB)

    Kochergin, Vladimir [MicroXact Inc., Blacksburg, VA (United States); Crawford, Michael A. [MicroXact Inc., Blacksburg, VA (United States)

    2015-09-01

    The main obstacle Photovoltaic (PV) industry is facing at present is the higher cost of PV energy compared to that of fossil energy. While solar cell efficiencies continue to make incremental gains these improvements are so far insufficient to drive PV costs down to match that of fossil energy. Improved in-line diagnostics however, has the potential to significantly increase the productivity and reduce cost by improving the yield of the process. On this Phase I/Phase II SBIR project MicroXact developed and demonstrated at CIGS pilot manufacturing line a high-throughput in-line PV manufacturing diagnostic system, which was verified to provide fast and accurate data on the spatial uniformity of thickness, an composition of the thin films comprising the solar cell as the solar cell is processed reel-to-reel. In Phase II project MicroXact developed a stand-alone system prototype and demonstrated the following technical characteristics: 1) ability of real time defect/composition inconsistency detection over 60cm wide web at web speeds up to 3m/minute; 2) Better than 1mm spatial resolution on 60cm wide web; 3) an average better than 20nm spectral resolution resulting in more than sufficient sensitivity to composition imperfections (copper-rich and copper-poor regions were detected). The system was verified to be high vacuum compatible. Phase II results completely validated both technical and economic feasibility of the proposed concept. MicroXact’s solution is an enabling technique for in-line PV manufacturing diagnostics to increase the productivity of PV manufacturing lines and reduce the cost of solar energy, thus reducing the US dependency on foreign oil while simultaneously reducing emission of greenhouse gasses.

  3. Optimum Design Of PV Systems For BTS In Remote And Urban Areas

    Directory of Open Access Journals (Sweden)

    Khaled Hossam

    2015-08-01

    Full Text Available knowing that Base stations represent the main contributor to the energy consumption of a mobile network the economical problem of providing electrical energy to mobile BTS stations may be solved to a great extent if renewable energy sources are used. In remote areas where electric utility is not available photovoltaic PV stand-alone system using storage batteries represent a good solution although it is costly. It is also possible to have a hybrid stand-alone system using diesel generator combined with PV to supply BTS stations in remote areas. In urban areas PV on grid system is an economical solution. In such a system during sunshine hours PV system delivers part of its generated energy to BTS station and the rest to grid utility whereas during night BTS station is supplied by grid to get back what was supplied to the grid during day. The economics of the different proposals is the criterion of optimization i.e. the cost per generated Kwh is the crucial objective function to be minimized. In this work we optimize both stand-alone PV system and PV on grid system to supply remote and urban indoor or outdoor BTS stations.

  4. IEA PVPS Task 3. Use of photovoltaic systems in stand-alone and island applications. 'Swiss participation'; IEA PVPS Task 3. Use of photovoltaic systems in stand-alone and island applications. 'Participation Suisse'

    Energy Technology Data Exchange (ETDEWEB)

    Villoz, M. [Dynatex SA, Morges (Switzerland)

    2004-07-01

    This report describes the work done during five years of the second phase of Task 3 of the photovoltaic power systems programme of the International Energy Agency (IEA-PVPS). Task 3 activities were concentrated on stand-alone photovoltaic systems with the main effort on improving the quality and reducing the cost of these systems. The work was divided in 2 sub-tasks whose first one was concentrated on quality insurance schemes and second one on technical recommendations coming from practical experience. Twelve original reports have been published covering topics that can be sorted in 4 categories: the first one is dedicated on quality issues with a review of existing standards in the participating countries and a double paper giving quality assurance recommendations on project management and examples of applying these rules in practical cases. The second category dwelled on photovoltaic systems with papers on charge controllers, on lightning protection and monitoring of systems. The third category presents interesting studies on the storage of energy which remains the main subject where improvements should be made in order to lower the cost of energy; four papers describe the management and the test procedures of lead-acid batteries, how to choose a lead-acid battery and finally are there alternatives to lead-acid batteries for the storage of photovoltaic electricity. The last category worked on loads and users of renewable energy and gives a large amount of experience with loads, how to choose them and how the energy can be better used through demand side management. (author)

  5. A Review of Hybrid Solar PV and Wind Energy System

    Directory of Open Access Journals (Sweden)

    Rashid Al Badwawi

    2015-07-01

    Full Text Available Due to the fact that solar and wind power is intermittent and unpredictable in nature, higher penetration of their types in existing power system could cause and create high technical challenges especially to weak grids or stand-alone systems without proper and enough storage capacity. By integrating the two renewable resources into an optimum combination, the impact of the variable nature of solar and wind resources can be partially resolved and the overall system becomes more reliable and economical to run. This paper provides a review of challenges and opportunities / solutions of hybrid solar PV and wind energy integration systems. Voltage and frequency fluctuation, and harmonics are major power quality issues for both grid-connected and stand-alone systems with bigger impact in case of weak grid. This can be resolved to a large extent by having proper design, advanced fast response control facilities, and good optimization of the hybrid systems. The paper gives a review of the main research work reported in the literature with regard to optimal sizing design, power electronics topologies and control. The paper presents a review of the state of the art of both grid-connected and stand-alone hybrid solar and wind systems.

  6. Design of a Stand-Alone Photovoltaic Model for Home Lightings and Clean Environment

    International Nuclear Information System (INIS)

    Ani, Vincent Anayochukwu

    2016-01-01

    This paper gives a well-documented health risk of fuel-based lighting (kerosene lamps and fuel-powered generators) and proposed a design of a stand-alone solar PV system for sustainable home lightings in rural Nigerian area. The design was done in three different patterns of electricity consumptions with energy efficient lightings (EELs) using two different battery types (Rolls Surrette 6CS25PS and Hoppecke 10 OpzS 1000) on; (i) judicious power consumption, (ii) normal power consumption, and (iii) excess power consumption; and compared them with the incandescent light bulb consumption. The stand-alone photovoltaic energy systems were designed to match the rural Nigerian sunlight and weather conditions to meet the required lightings of the household. The objective function and constraints for the design models were formulated and optimization procedures were used to demonstrate the best solution (reliability at the lowest lifecycle cost). Initial capital costs as well as annualized costs over 5, 10, 15, 20, and 25 years were quantified and documented. The design identified the most cost-effective and reliable solar and battery array among the patterns of electricity consumption with EEL options (judicious power consumption, normal power consumption, and excess power consumption).

  7. Techno-Economic Evaluation of a Stand-Alone Power System Based on Solar Power/Batteries for Global System for Mobile Communications Base Stations

    Directory of Open Access Journals (Sweden)

    Mohammed H. Alsharif

    2017-03-01

    Full Text Available Energy consumption in cellular networks is receiving significant attention from academia and the industry due to its significant potential economic and ecological influence. Energy efficiency and renewable energy are the main pillars of sustainability and environmental compatibility. Technological advancements and cost reduction for photovoltaics are making cellular base stations (BSs; a key source of energy consumption in cellular networks powered by solar energy sources a long-term promising solution for the mobile cellular network industry. This paper addresses issues of deployment and operation of two solar-powered global system for mobile communications (GSM BSs that are being deployed at present (GSM BS 2/2/2 and GSM BS 4/4/4. The study is based on the characteristics of South Korean solar radiation exposure. The optimum criteria as well as economic and technical feasibility for various BSs are analyzed using a hybrid optimization model for electric renewables. In addition, initial capital, replacement, operations, maintenance, and total net present costs for various solar-powered BSs are discussed. Furthermore, the economic feasibility of the proposed solar system is compared with conventional energy sources in urban and remote areas.

  8. Firefighter Safety for PV Systems

    DEFF Research Database (Denmark)

    Mathe, Laszlo; Sera, Dezso; Spataru, Sergiu

    2015-01-01

    An important and highly discussed safety issue for photovoltaic (PV) systems is that as long as the PV panels are illuminated, a high voltage is present at the PV string terminals and cables between the string and inverters that is independent of the state of the inverter's dc disconnection switch...

  9. Performance evaluation of a stand-alone solar dish Stirling system for power generation suitable for off-grid rural electrification

    International Nuclear Information System (INIS)

    Kadri, Y.; Hadj Abdallah, H.

    2016-01-01

    Highlights: • Estimation of the output temperature reached by 2 m parabolic dish. • Output power estimation for uncontrollable load was done using Matlab®. • Validation of the proposed system under Tunisian conditions for rural electrification. - Abstract: The development of green power generation such as solar systems that have become a great interest for several countries especially for Tunisia as it presents a significant solar potential. For this purpose, this research has investigated the feasibility and the performance of standalone solar dish/Stirling micro generation plant for rural electrification. The considered hybrid system includes solar dish/Stirling engine, permanent magnet synchronous generator and a storage battery. To start with, thermal modeling and simulation have been carried out using Matlab® for the solar-driven Stirling heat engine system composed of an Alpha Stirling engine, a solar collector and a receiver, in which the radiation, convection, conduction and radiation heat loss have been taken into consideration for the selected design. For numerical validation of the receiver’s thermal model, simulation results were compared with experimental measurements reported for the EURODISH system with a reasonable degree of agreement. Second, the generated torque driving the generator has been estimated by the Adiabatic model of URIELI based on the classical fourth-order Runge-Kutta. In order for an autonomous control, the dish generator is connected to the load via power electronic converters where the bidirectional power flow is possible by the use of two voltage source converters in a back-to-back configuration. They are referred to as Stirling/generator side converter and load side inverter, both are oriented control by space vector pulse width modulation. In this context, the Stirling side converter is used to adjust the synchronous generator while the inverter controls the power flow between the direct current bus and the

  10. Loss Distribution Analysis of a Three-Port Converter for Low-Power Stand-Alone Light-to-Light Systems

    DEFF Research Database (Denmark)

    Mira Albert, Maria del Carmen; Knott, Arnold; Andersen, Michael A. E.

    2016-01-01

    . The separation of the power flows allows to replace the conventional solution of two cascaded converters into a single structure with shared components. A loss distribution analysis of the proposed structure is performed, which shows very good match with the experimental results. A prototype of the TPC......In locations far from the equator achieving high conversion efficiency in low-power solar systems is challenging due to low solar irradiance levels. This paper presents a high efficiency three-port converter (TPC) for light-to-light (LtL) applications where no direct solar conversion is required...... demonstrates high efficiency in both power flow paths. At low irradiation level, the power flow from the photovoltaic panel to the battery shows a peak efficiency of 99.1% at at 1.5 W output power, and the LED driver stage presents a peak efficiency of 97.3% at 3 W output power....

  11. A stand-alone tree demography and landscape structure module for Earth system models: integration with inventory data from temperate and boreal forests

    Science.gov (United States)

    Haverd, V.; Smith, B.; Nieradzik, L. P.; Briggs, P. R.

    2014-08-01

    Poorly constrained rates of biomass turnover are a key limitation of Earth system models (ESMs). In light of this, we recently proposed a new approach encoded in a model called Populations-Order-Physiology (POP), for the simulation of woody ecosystem stand dynamics, demography and disturbance-mediated heterogeneity. POP is suitable for continental to global applications and designed for coupling to the terrestrial ecosystem component of any ESM. POP bridges the gap between first-generation dynamic vegetation models (DVMs) with simple large-area parameterisations of woody biomass (typically used in current ESMs) and complex second-generation DVMs that explicitly simulate demographic processes and landscape heterogeneity of forests. The key simplification in the POP approach, compared with second-generation DVMs, is to compute physiological processes such as assimilation at grid-scale (with CABLE (Community Atmosphere Biosphere Land Exchange) or a similar land surface model), but to partition the grid-scale biomass increment among age classes defined at sub-grid-scale, each subject to its own dynamics. POP was successfully demonstrated along a savanna transect in northern Australia, replicating the effects of strong rainfall and fire disturbance gradients on observed stand productivity and structure. Here, we extend the application of POP to wide-ranging temporal and boreal forests, employing paired observations of stem biomass and density from forest inventory data to calibrate model parameters governing stand demography and biomass evolution. The calibrated POP model is then coupled to the CABLE land surface model, and the combined model (CABLE-POP) is evaluated against leaf-stem allometry observations from forest stands ranging in age from 3 to 200 year. Results indicate that simulated biomass pools conform well with observed allometry. We conclude that POP represents an ecologically plausible and efficient alternative to large-area parameterisations of woody

  12. The PV market

    International Nuclear Information System (INIS)

    Hammond, B.

    1992-01-01

    This paper forecasts the photovoltaic (PV) market growth for the 1990s. Ten years of PV history are reviewed and used to establish market trends in terms of average selling price (ASP) and kilowatts shipped by market segment. The market is segmented into indoor consumer, stand-alone, and grid-connected applications. Indoor consumer presently represents a saturated market and is fairly predictable. The stand-alone market (i.e. not connected to the utility grid) is fairly stable and predictable. The utility PV market however is highly dependent on a number of market factors such as the cost of conventional energy the cost of PV systems utility acceptance of PV and regulatory controls. Government and institutional regulations, environmental issues, and OPEC and Middle East politics will have the greatest impact on the cost of conventional fuels. Private and federal investment in PV technology development could have a significant impact on the cost of PV systems. Forecasts are provided through the year 2000 for indoor consumer stand-alone and utility markets

  13. Hydrogen Gas Production in a Stand-Alone Wind Farm

    Directory of Open Access Journals (Sweden)

    M. Naziry Kordkandy

    2017-04-01

    Full Text Available This paper is analyzing the operation of a stand-alone wind farm with variable speed turbines, permanent magnet synchronous generators (PMSG and a system for converting wind energy during wind speed variations. On this paper, the design and modeling of a wind system which uses PMSG’s to provide the required power of a hydrogen gas electrolyzer system, is discussed. This wind farm consists of three wind turbines, boost DC-DC converters, diode full bridge rectifiers, permanent magnet synchronous generators, MPPT control and a hydrogen gas electrolyzer system. The MPPT controller based on fuzzy logic is designed to adjust the duty ratio of the boost DC-DC converters to absorb maximum power. The proposed fuzzy logic controller assimilates, with (PSF MPPT algorithm which generally used to absorb maximum power from paralleled wind turbines and stores it in form of hydrogen gas. The system is modeled and its behavior is studied using the MATLAB software.

  14. 39 CFR 122.2 - Stand-alone special services.

    Science.gov (United States)

    2010-07-01

    ... 39 Postal Service 1 2010-07-01 2010-07-01 false Stand-alone special services. 122.2 Section 122.2 Postal Service UNITED STATES POSTAL SERVICE POST OFFICE SERVICES [DOMESTIC MAIL] SERVICE STANDARDS FOR MARKET-DOMINANT SPECIAL SERVICES PRODUCTS § 122.2 Stand-alone special services. (a) The service standard...

  15. Integral type small PWR with stand-alone safety

    International Nuclear Information System (INIS)

    Makihara, Yoshiaki

    2001-01-01

    A feasibility study is achieved on an integral type small PWR with stand-alone safety. It is designed to have the following features. (1) The coolant does not leak out at any accidental condition. (2) The fuel failure does never occur while it is supposed on the large scale PWR at the design base accident. (3) At any accidental condition the safety is secured without any support from the outside (stand-alone safety secure). (4) It has self-regulating characteristics and easy controllability. The above features can be satisfied by integrate the steam generator and CRDM in the reactor vessel while the pipe line break has to be considered on the conventional PWR. Several counter measures are planned to satisfy the above features. The economy feature is also attained by several simplifications such as (1) elimination of main coolant piping and pressurizer by the integration of primary cooling system and self-pressurizing, (2) elimination of RCP by application of natural circulating system, (3) elimination of ECCS and accumulator by application of static safety system, (4) large scale volume reduction of the container vessel by application of integrated primary cooling system, (5) elimination of boric acid treatment by deletion of chemical shim. The long operation period such as 10 years can be attained by the application of Gd fuel in one batch refueling. The construction period can be shortened by the standardizing the design and the introduction of modular component system. Furthermore the applicability of the reduced modulation core is also considered. (K. Tsuchihashi)

  16. Poster - Thurs Eve-17: Stand alone software for deforming delivered dose distributions to account for daily anatomical variations in prostate patients treated on the TomoTherapy Hi-Art II system.

    Science.gov (United States)

    Rivest, R; Riauka, T; Murtha, A; Fallone, G

    2008-07-01

    The acquisition of daily megavoltage (MV)-CT images provides an invaluable tool in the delivery of adaptive radiotherapy (ART) on the TomoTherapy Hi-ART II system. Using TomoTherapy's Planned Adaptive software, delivery sinograms can be applied to pre-treatment MVCT images to generate daily delivered dose distributions, allowing for the potential comparison of planned and delivered doses. However, daily patient anatomical variations complicate the task and accurate comparison requires that daily doses be evaluated in the same references frame as the planned dose. Each anatomical point in daily MVCT images must be mapped to its corresponding point in the patient planning CT and that deformation map must be applied to the daily dose distribution. Stand alone software has been developed for the comparison of planned and delivered doses for TomoTherapy prostate patients. Software inputs are the planning CT, planning structure data, planned dose distribution, daily MVCT and delivered dose distribution. The software uses an in-house developed automatic voxel-based deformable registration algorithm designed and optimized specifically for the registration of prostate CT images to achieve anatomical correspondence between MVCT and planning images. The resultant deformation map is applied to the daily dose distribution and the software outputs the deformed daily dose distribution in the planning CT's reference frame, as well as a delivered DVH for each of the planning CT's ROI. The software allows for a number of potential research opportunities, in particular, the calculation of the cumulative dose delivered over the course of treatment for prostate patients treated on the Hi-Art II system. © 2008 American Association of Physicists in Medicine.

  17. PV solar system feasibility study

    International Nuclear Information System (INIS)

    Ashhab, Moh’d Sami S.; Kaylani, Hazem; Abdallah, Abdallah

    2013-01-01

    Highlights: ► This research studies the feasibility of PV solar systems. ► The aim is to develop the theory and application of a hybrid system. ► Relevant research topics are reviewed and some of them are discussed in details. ► A prototype of the PV solar system is designed and built. - Abstract: This research studies the feasibility of PV solar systems and aims at developing the theory and application of a hybrid system that utilizes PV solar system and another supporting source of energy to provide affordable heating and air conditioning. Relevant research topics are reviewed and some of them are discussed in details. Solar heating and air conditioning research and technology exist in many developed countries. To date, the used solar energy has been proved to be inefficient. Solar energy is an abundant source of energy in Jordan and the Middle East; with increasing prices of oil this source is becoming more attractive alternative. A good candidate for the other system is absorption. The overall system is designed such that it utilizes solar energy as a main source. When the solar energy becomes insufficient, electricity or diesel source kicks in. A prototype of the PV solar system that operates an air conditioning unit is built and proper measurements are collected through a data logging system. The measured data are plotted and discussed, and conclusions regarding the system performance are extracted.

  18. Basic Stand Alone Skilled Nursing Facility Beneficiary PUF

    Data.gov (United States)

    U.S. Department of Health & Human Services — This release contains the Basic Stand Alone (BSA) Skilled Nursing Facility (SNF) Beneficiary Public Use Files (PUF) with information from Medicare SNF claims. The...

  19. Basic Stand Alone Medicare Home Health Beneficiary PUF

    Data.gov (United States)

    U.S. Department of Health & Human Services — This release contains the Basic Stand Alone (BSA) Home Health Agency (HHA) Beneficiary Public Use Files (PUF) with information from Medicare HHA claims. The CMS BSA...

  20. Basic Stand Alone Medicare DME Line Items PUF

    Data.gov (United States)

    U.S. Department of Health & Human Services — This release contains the Basic Stand Alone (BSA) Durable Medical Equipment (DME) Line Items Public Use Files (PUF) with information from Medicare DME claims. The...

  1. STAND-ALONE WIND ENERGY CONVERSION SYSTEM WITH MAXIMUM POWER TRANSFER CONTROL SISTEMA AISLADO DE CONVERSIÓN EÓLICA CON CONTROL DE MÁXIMA TRANSFERENCIA DE POTENCIA

    Directory of Open Access Journals (Sweden)

    Miguel López

    2009-12-01

    Full Text Available A controlled wind generation system for a stand alone application is presented in this paper. A cascaded step-up/step-down power electronic converters topology is proposed to control the wind power system in the whole wind speed range. For the low wind speed range, the control strategy is aimed to follow the wind turbine’s maximal power coefficient by adjusting the generator’s rotational speed. For high wind speeds, the system power regulation is also made by controlling the generator speed. This control is made by the DC/DC power electronic converter, which modifies its input voltage, changing the machine voltage and consequently varying the generator’s rotor speed. The proposed system is validated by computer simulation. The proposed control system shows a good performance for its application in autonomous wind energy systems.Un sistema de generación eólica para una aplicación aislada es presentado en este artículo. Una topología de convertidores electrónicos de potencia elevador y reductor conectados en cascada es propuesta para controlar la producción eólica en todo el rango de velocidades del viento. Para el rango de vientos suaves, la estrategia de control permite seguir el máximo coeficiente de potencia de turbina eólica mediante el ajuste de la velocidad de rotación del generador. En el rango de vientos fuertes, la regulación de la potencia del sistema se hace igualmente por control de la velocidad de giro del generador. La acción de control es realizada mediante el convertidor DC/DC de potencia el cual modifica su tensión de entrada, cambiando así la tensión en los terminales de la máquina y por consecuencia variando la velocidad de rotación del generador. El sistema propuesto es validado mediante simulación por computador. Los resultados muestran que el sistema de control propuesto actúa de buena manera para su aplicación en sistemas autónomos de generación eólica.

  2. Stand-alone tsunami alarm equipment

    Science.gov (United States)

    Katsumata, Akio; Hayashi, Yutaka; Miyaoka, Kazuki; Tsushima, Hiroaki; Baba, Toshitaka; Catalán, Patricio A.; Zelaya, Cecilia; Riquelme Vasquez, Felipe; Sanchez-Olavarria, Rodrigo; Barrientos, Sergio

    2017-05-01

    One of the quickest means of tsunami evacuation is transfer to higher ground soon after strong and long ground shaking. Ground shaking itself is a good initiator of the evacuation from disastrous tsunami. Longer period seismic waves are considered to be more correlated with the earthquake magnitude. We investigated the possible application of this to tsunami hazard alarm using single-site ground motion observation. Information from the mass media is sometimes unavailable due to power failure soon after a large earthquake. Even when an official alarm is available, multiple information sources of tsunami alert would help people become aware of the coming risk of a tsunami. Thus, a device that indicates risk of a tsunami without requiring other data would be helpful to those who should evacuate. Since the sensitivity of a low-cost MEMS (microelectromechanical systems) accelerometer is sufficient for this purpose, tsunami alarm equipment for home use may be easily realized. Amplitude of long-period (20 s cutoff) displacement was proposed as the threshold for the alarm based on empirical relationships among magnitude, tsunami height, hypocentral distance, and peak ground displacement of seismic waves. Application of this method to recent major earthquakes indicated that such equipment could effectively alert people to the possibility of tsunami.

  3. Sensorless direct voltage control of the stand-alone brushless doubly-fed generator

    DEFF Research Database (Denmark)

    Liu, Yi; Xu, Wei; Xiong, Fei

    2017-01-01

    The conventional stand-alone brushless doubly-fed generator (BDFG) control strategies need the feedback from the rotor position or speed sensors, which can reduce system reliability and increase the cost and axial volume of the machine. In this paper, a sensorless direct voltage control (DVC......) strategy is presented for the stand-alone BDFG. The satisfactory dynamic performance is verified by experimental results under four kinds of typical operation conditions. Besides, the proposed control strategy is robust due to no generator parameters being required....

  4. A control strategy for stand-alone wound rotor induction machine

    Energy Technology Data Exchange (ETDEWEB)

    Forchetti, D.G.; Garcia, G.O. [Grupo de Electronica Aplicada (GEA), Universidad Nacional de Rio Cuarto, X5804 BYA Rio Cuarto (Argentina); Solsona, J.A. [Instituto de Investigaciones en Ingenieria Electrica?Alfredo Desages?, Departamento de Ingenieria Electrica y de Computadoras, Universidad Nacional del Sur, Bahia Blanca (Argentina); Valla, M.I. [Laboratorio de Electronica Industrial, Control e Instrumentacion (LEICI), Facultad de Ingenieria, Universidad Nacional de La Plata, 1900 La Plata (Argentina)

    2007-02-15

    A control strategy to regulate the frequency and voltage of a stand-alone wound rotor induction machine is presented. This strategy allows the machine to work as a generator in stand-alone systems (without grid connection) with variable rotor speed. A stator flux-oriented control is proposed using the rotor voltages as actuation variables. Two cascade control loops are used to regulate the stator flux and the rotor currents. A closed loop observer is designed to estimate the machine flux which is necessary to implement these control loops. The proposed control strategy is validated through simulations with satisfactory results. (author)

  5. Hydrogen Production from Optimal Wind-PV Energies Systems

    International Nuclear Information System (INIS)

    T Tafticht; K Agbossou

    2006-01-01

    Electrolytic hydrogen offers a promising alternative for long-term energy storage of renewable energies (RE). A stand-alone RE system based on hydrogen production has been developed at the Hydrogen Research Institute and successfully tested for automatic operation with designed control devices. The system is composed of a wind turbine, a photovoltaic (PV) array, an electrolyzer, batteries for buffer energy storage, hydrogen and oxygen storage tanks, a fuel cell, AC and DC loads, power conditioning devices and different sensors. The long-term excess energy with respect to load demand has been sent to the electrolyser for hydrogen production and then the fuel cell has utilised this stored hydrogen to produce electricity when there were insufficient wind and solar energies with respect to load requirements. The RE system components have substantially different voltage-current characteristics and they are integrated on the DC bus through power conditioning devices for optimal operation by using the developed Maximum Power Point Tracking (MPPT) control method. The experimental results show that the power gain obtained by this method clearly increases the hydrogen production and storage rate from wind-PV systems. (authors)

  6. Improving efficiency of a regional stand alone bone bank.

    Science.gov (United States)

    Warnock, Jonathan M; Rowan, Clare H; Davidson, Helen; Millar, Ciara; McAlinden, M Gavan

    2016-03-01

    The introduction of a stand-alone Bone Bank in our Regional Orthopaedic Hospital has improved the availability of femoral head allograft. Benninger et al. (Bone Joint J 96-B:1307-1311, 2014), demonstrated their institutions bank to be cost effective despite a 30 % discard rate for harvested allograft. We sought to audit our own discard rates and subsequent cost-effectiveness of our bone bank. Donor recruitment. Before approaching a potential donor, our establishment's nurse specialists review their clinical notes and biochemical laboratory results, available on a regional Electronic Care Records. They view femoral head architecture on radiographs against set criteria, Patient Archive and Communication system (SECTRA, Sweden). In total 1383 femoral heads were harvested, 247 were discarded giving an overall rate of 17.9 %. The most common reasons for discard of harvested graft was a positive microbiology/bacteriology result, n = 96 (38.9 %). After a rise in discard rates in 2007, we have steadily reduced our discard rates since 2006/2007 (28.2 %), 2008/2009 (17 %), 2010/2011 (14.8 %), and finally to 10.3 % in 2012/2013. In the current financial year, our cost to harvest, test, store and release a femoral head is £ 610. With a structured donor recruitment process and unique pre-operative radiographic analysis we have successfully reduced our discard rates bi-annually making our bone bank increasingly cost-effective.

  7. 11kW stand alone wind turbine based on proven wind turbine

    DEFF Research Database (Denmark)

    Bindner, H.; Wodstrup, J.; Andersen, J.

    2004-01-01

    and enable control of frequency and voltage independently on both the grid side and the generator side. The prototype has been installed at Risø. The paper will present results from test runs of the system both operating stand-alone supplying a single load and in parallel operation with a diesel genset....

  8. Environmental/Climatic Effect on Stand-Alone Solar Energy Supply ...

    African Journals Online (AJOL)

    This paper investigates the climatic eects and environmental variations on the performance of a stand-alone photovoltaic system. The eects of partial shading with dierent climate conditions and load resistance variations were examined. A survey of some of the work done in this eld of environmental eect on solar panel was ...

  9. Lightning protection of PV systems

    OpenAIRE

    Pons, Enrico; Tommasini, Riccardo

    2013-01-01

    Lightning strikes can affect photovoltaic (PV) generators and their installations, involving also the inverter's electronics. It is therefore necessary to evaluate the risk connected to lightning strikes in order to adopt the correct protective measures for the system. The Standard IEC (EN) 62305-2 reports the procedures for the risk calculation and for the choice of proper lightning protection systems. Usually the technical guidelines suggest protecting with SPDs (surge protective devices) b...

  10. The stand-alone test and decreasing serial cost sharing

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Thorlund-Petersen, Lars

    2000-01-01

    The rule of decreasing serial cost sharing defined in de Frutos [1] over the class of concave cost functions may violate the important stand-alone test. Sufficient conditions for the test to be satisfied are given, in terms of individual rationality as well as coalitional stability...

  11. Building integrated multi PV/T/A solar system

    International Nuclear Information System (INIS)

    Ami Elazari

    2000-01-01

    Previous development in solar energy for residential applications proved that there is merit in further development and improvement of combined electricity and hot water and hot air collectors. The justification stems from the fact that waste heat is generated when PV cells are producing electricity but it decrease its efficiency dramatically, and any effective way to cool the cells can improve their efficiency and long while the heat that generated from this cooling process could be stored and used as standard solar hot water/air system. The core unit comprises of integrated PV cells mounted on a flat-plate collector for water and air, hot water storage tank hot air inlet pips to the house electric battery bank, inverter, connecting cables and controller. Double-glazing serving as solar trap to triple the amount of sun ray reaching the PV cells and other technical innovation make the system more cost effective and cost benefit for stand alone and grid connected domestic application. Two way interconnection with the electric grid like in all the roof top program may bring it to economic viability by selling excess electricity during the costly peak hours while buying low cost electricity during the night off-peak hours, and free electricity from the sun plus free hot water and hot air for domestic use as by-product. A basic domestic two-collector system may deliver up to 4 kWh of electricity and 12000 kcal of hot water and air daily. Some 22 systems are currently operating at various locations in Israel, some for 8 years with very good results. (Author)

  12. Experimental validation of autonomous PV-based water pumping system optimum sizing

    International Nuclear Information System (INIS)

    Kaldellis, J.K.; Spyropoulos, G.C.; Kavadias, K.A.; Koronaki, I.P.

    2009-01-01

    The progress met in the world market of photovoltaics underlines the maturity of investments realized, guarantees the reliability of the technology utilized and designates the variety of applications in covering the energy demands of both stand-alone and grid connected consumers. Concerning stand-alone systems, the incorporation of photovoltaic systems in water pumping applications is thought to be one of the most popular and ideal uses of solar energy exploitation, especially under the common allegation of coincidence between insolation and water demand. In this study, an attempt to investigate the opportunities of a PV powered water pumping system able to meet additional - apart from the water pump - electricity loads, results in the development of an optimum sizing methodology which is accordingly validated by experimental measurements. From the results obtained, it becomes clear that a properly designed PV-pumping configuration of 610 W p is capable of covering both the electricity (max 2 kWh/day) and the water (max 400 L/h) management demands of a large variety of remote consumers. (author)

  13. Brackish water desalination by a stand alone reverse osmosis desalination unit powered by photovoltaic solar energy

    Energy Technology Data Exchange (ETDEWEB)

    Hrayshat, Eyad S. [Tafila Technical University, P.O. Box 66, Tafila 66110 (Jordan)

    2008-08-15

    Desalination of brackish water as a viable option to cope with water scarcity and to overcome water deficit in Jordan is assessed. A stand alone reverse osmosis (RO) desalination unit powered by photovoltaic (PV) solar energy is proposed, and a computer code in C++ was generated in order to simulate the process, and to predict the water production at 10 selected sites based on the available solar radiation data, sunshine hours and salinity of the feed water (TDS of 3000, 5000, 7000, and 10,000 mg/L). It was found that most of the selected sites showed favorable application of the proposed system in Jordan. Tafila, Queira, Ras Muneef, H-4, and H-5 are the most favorable sites. With TDS of 7000 mg/L, the highest annual water production of 1679 m{sup 3}/year was observed in Tafila, followed by Queira with production of 1473 m{sup 3}/year. Ras Muneef, H-4, and H-5 showed close to each other production of 1363, 1345, and 1340 m{sup 3}/year, respectively. Among the most favorable sites (Tafila, Queira, Ras Muneef, H-4, and H-5), Ras Muneef was found to be the best site in terms of the daily amount of water produced during the driest months of the year (May-September). Its production during these months forms about 65% of its total daily water production during a 1-year cycle, while for each of the other most favorable sites namely Tafila, Queira, H-4, and H-5, a 61% of production was observed during the same period. (author)

  14. Radon Monitoring in Army Stand-Alone Housing Units

    Science.gov (United States)

    1990-04-01

    Y cm a cc 0000 0003 000 000 :: - -@-I.00 cmjinu mooc . 0J~CJ~ TTTT J !8 2 T WWWW WW.000 coo 0~~ 80 Im - v ;o e I3 ec ;: C -1,4 04. -c mco : - a c W" 1 .1...Chamber ....................... 25 V U I I I viI Final Report, April 1990 Radon Monitoring in Army Stand-alone Housing Units Summary Argonne National...and analysis. The quality control protocols appli- cable to detector analysis are contained in Chapter V of the procedures manual developed by Tech

  15. Modified Chaos Particle Swarm Optimization-Based Optimized Operation Model for Stand-Alone CCHP Microgrid

    Directory of Open Access Journals (Sweden)

    Fei Wang

    2017-07-01

    Full Text Available The optimized dispatch of different distributed generations (DGs in stand-alone microgrid (MG is of great significance to the operation’s reliability and economy, especially for energy crisis and environmental pollution. Based on controllable load (CL and combined cooling-heating-power (CCHP model of micro-gas turbine (MT, a multi-objective optimization model with relevant constraints to optimize the generation cost, load cut compensation and environmental benefit is proposed in this paper. The MG studied in this paper consists of photovoltaic (PV, wind turbine (WT, fuel cell (FC, diesel engine (DE, MT and energy storage (ES. Four typical scenarios were designed according to different day types (work day or weekend and weather conditions (sunny or rainy in view of the uncertainty of renewable energy in variable situations and load fluctuation. A modified dispatch strategy for CCHP is presented to further improve the operation economy without reducing the consumers’ comfort feeling. Chaotic optimization and elite retention strategy are introduced into basic particle swarm optimization (PSO to propose modified chaos particle swarm optimization (MCPSO whose search capability and convergence speed are improved greatly. Simulation results validate the correctness of the proposed model and the effectiveness of MCPSO algorithm in the optimized operation application of stand-alone MG.

  16. Optimal sizing of hybrid PV/diesel/battery in ship power system

    International Nuclear Information System (INIS)

    Lan, Hai; Wen, Shuli; Hong, Ying-Yi; Yu, David C.; Zhang, Lijun

    2015-01-01

    Highlights: • An optimal sizing method is developed for a hybrid PV/diesel/ESS ship power system. • The output of PV along a navigation route is explored for the ship power system. • Five operating conditions of the load in the ship power system are modeled. • The impact of various prices of PV on cost is studied. - Abstract: Owing to the strict restrictions imposed by the Marine Pollution Protocol and the rapid development of renewable energy, the use of solar generation and energy storage systems in ship power systems has been increasingly attracting attention. However, the improper sizing of a hybrid power generation system in a ship power system will result in a high investment cost and increased greenhouse gas emission. This paper proposes a method for determining the optimal size of the photovoltaic (PV) generation system, the diesel generator and the energy storage system in a stand-alone ship power system that minimizes the investment cost, fuel cost and the CO 2 emissions. The power generation from PV modules on a ship relies on the date, local time, time zone, longitude and latitude along a navigation route and is different from the conditions of power systems on land. Thus, a method, which takes the seasonal and geographical variation of solar irradiations and temperatures along the route from Dalian in China to Aden in Yemen into account, for correcting the output of PV modules is developed in this paper. The proposed method considers five conditions along the navigation route to model the total ship load. Four cases are studied in details to demonstrate the applicability of the proposed algorithm.

  17. 49 CFR 1111.8 - Procedural schedule in stand-alone cost cases.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 8 2010-10-01 2010-10-01 false Procedural schedule in stand-alone cost cases... § 1111.8 Procedural schedule in stand-alone cost cases. (a) Procedural schedule. Absent a specific order by the Board, the following general procedural schedule will apply in stand-alone cost cases: Day 0...

  18. Stand-alone photovoltaic system: study of a modular concept with distributed communication and control units; Systeme photovoltaique autonome: etude d'une structure modulaire a gestion repartie

    Energy Technology Data Exchange (ETDEWEB)

    Neusser, A.

    2004-09-15

    This thesis concerns an innovative photovoltaic system concept, which is modular am where the standardisation of all of the components is possible. Lead-acid batteries tare used to store the energy. The main objective of this project is the improvement of the battery management process in the system. As the batteries are the weak point of the system, a new battery charger is developed aiming at a longer life-span and a homogeneous ageing rate for all of them. This charger permits energy exchanges, which are co-ordinated by a communication system. We use a DC/DC converter as power electronics for battery charging. PSpice simulations and tests verify its performance. Simulations with Matlab Simulink show the auto-equalization tendency of the chosen battery management method. In addition, an experimentation under real conditions validates the beneficial effect on the state of health of the batteries. (author)

  19. Multifunctional a-Si PV systems

    Energy Technology Data Exchange (ETDEWEB)

    Peippo, K.; Lund, P.; Vartiainen, E. [Helsinki Univ. of Technology, Otaniemi (Finland). Advanced Energy Systems

    1998-10-01

    The optimal use of the various forms of solar energy (passive, active, daylighting, photovoltaics) in buildings calls for an optimal integration of the technologies. As energy conservation potential in space heating may soon be exhausted, electricity efficiency and on-site generation will play an increasing role in energy-conscious building design. There, dispersed PV systems integrated into buildings show a significant market potential, due to a number of benefits: no extra land area is required, PV-array may replace conventional cladding materials and become a building element. Moreover, the produced PV-electricity is more valuable for the building owner than for an electric utility

  20. A stochastic simulation model for reliable PV system sizing providing for solar radiation fluctuations

    International Nuclear Information System (INIS)

    Kaplani, E.; Kaplanis, S.

    2012-01-01

    Highlights: ► Solar radiation data for European cities follow the Extreme Value or Weibull distribution. ► Simulation model for the sizing of SAPV systems based on energy balance and stochastic analysis. ► Simulation of PV Generator-Loads-Battery Storage System performance for all months. ► Minimum peak power and battery capacity required for reliable SAPV sizing for various European cities. ► Peak power and battery capacity reduced by more than 30% for operation 95% success rate. -- Abstract: The large fluctuations observed in the daily solar radiation profiles affect highly the reliability of the PV system sizing. Increasing the reliability of the PV system requires higher installed peak power (P m ) and larger battery storage capacity (C L ). This leads to increased costs, and makes PV technology less competitive. This research paper presents a new stochastic simulation model for stand-alone PV systems, developed to determine the minimum installed P m and C L for the PV system to be energy independent. The stochastic simulation model developed, makes use of knowledge acquired from an in-depth statistical analysis of the solar radiation data for the site, and simulates the energy delivered, the excess energy burnt, the load profiles and the state of charge of the battery system for the month the sizing is applied, and the PV system performance for the entire year. The simulation model provides the user with values for the autonomy factor d, simulating PV performance in order to determine the minimum P m and C L depending on the requirements of the application, i.e. operation with critical or non-critical loads. The model makes use of NASA’s Surface meteorology and Solar Energy database for the years 1990–2004 for various cities in Europe with a different climate. The results obtained with this new methodology indicate a substantial reduction in installed peak power and battery capacity, both for critical and non-critical operation, when compared to

  1. Performance, costs, and GHG emissions of PV-hybrid systems : current status and avenues for improvement

    Energy Technology Data Exchange (ETDEWEB)

    Ross, M.M.D. [RER Renewable Energy Research, Montreal, PQ (Canada)

    2007-07-01

    The performance of a baseline 300 W photovoltaic (PV) hybrid system was investigated and compared with a prime power system, a genset battery system, and a PV-battery system. The analysis considered initial and annual costs, energy production, and greenhouse gas (GHG) emissions. An economic analysis of the overall life-cycle cost of the systems was provided. Simulations were used to determine system performance in both residential areas and in a remote off-grid industrial scenario. Hourly monitored weather data for a 5 year period in various Canadian cities were used to simulate 6 different PV-hybrid system configurations, namely 14 genset-battery configurations, 2 prime power configurations, and a stand-alone PV-battery system. A battery with 2 days of autonomy was used for both the genset battery and the PV hybrid system. The prime power system consisted of a 5 kW diesel genset and a rectifier with a 92.5 per cent efficiency at 50 W. The PV array was designed to achieve an annual solar fraction of 65 per cent. Data collected from a GNB Absolyte IIP absorbent glass mat batter was used to characterize the current-voltage behaviour of the battery model. The study considered battery capacity deterioration, fractions of solar energy wasted, as well as the fraction of wasted energy that could be avoided through the use of non-seasonal storage. The overall cost of generating electricity was calculated by considering equivalent annual costs divided by the electrical energy required annually. Results of the analysis indicated that prime power systems were not suitable for remote, industrial applications. Results of the residential analysis indicated that the PV-battery system was less economically viable than either the genset-battery or the PV hybrid system. The higher fuel consumption of the genset-battery system resulted in greenhouse gas emissions that were 3 times as high as those observed with the hybrid system, which generated 0.9 tonnes of carbon dioxide

  2. Sensorless PV Array Diagnostic Method for Residential PV Systems

    DEFF Research Database (Denmark)

    Sera, Dezso; Spataru, Sergiu; Mathe, Laszlo

    2011-01-01

    This work proposes a temperature and irradiance sensorless diagnostic method suitable for small residential PV installations, focusing on detection of partial shadows. The method works by detection of failures in crystalline silicone PV arrays by concomitant monitoring of some of their key...

  3. PV Obelisk - Information system with photovoltaics

    International Nuclear Information System (INIS)

    Ruoss, D.; Rasmussen, J.

    2004-01-01

    This final report for the Swiss Federal Office of Energy (SFOE) describes the development of an information system powered by a photovoltaic (PV) array. As an innovative approach, the 'PV-Obelisk' project is the combination of PV with a multi-functional pillar made of natural stone in an aesthetic way. The PV modules serve both as a power supply and as a design element. Two initial prototypes led the way to a third, optimised consumer configuration that was planned to guarantee maximum user frequency. Test operation in front of the 'Heidiland' motor way restaurant confirmed the market analyses made and delivered the expected results. The product, whose three LCD displays are updated via a mobile telephony-based text-message system, proved its technical reliability and showed a high user frequency. Because of the high overall energy consumption, PV power can only partially contribute to the energy supply needed. Various compromises in the technical and aesthetic areas are discussed that were made for the sake of product acceptance in the market. The range of application areas for such a 'PV Obelisk' are discussed and the need for early co-ordination with urban planners is stressed

  4. Coordination Control Strategy for AC/DC Hybrid Microgrids in Stand-Alone Mode

    Directory of Open Access Journals (Sweden)

    Dwi Riana Aryani

    2016-06-01

    Full Text Available Interest in DC microgrids is rapidly increasing along with the improvement of DC power technology because of its advantages. To support the integration process of DC microgrids with the existing AC utility grids, the form of hybrid AC/DC microgrids is considered for higher power conversion efficiency, lower component cost and better power quality. In the system, AC and DC portions are connected through interlink bidirectional AC/DC converters (IC with a proper control system and power management. In the stand-alone operation mode of AC/DC hybrid microgrids, the control of power injection through the IC is crucial in order to maintain the system security. This paper mainly deals with a coordination control strategy of IC and a battery energy storage system (BESS converter under stand-alone operation. A coordinated control strategy for the IC, which considers the state of charge (SOC level of BESS and the load shedding scheme as the last resort, is proposed to obtain better power sharing between AC and DC subgrids. The scheme will be tested with a hybrid AC/DC microgrid, using the tool of the PSCAD/EMTDC software.

  5. Seasonal energy storage - PV-hydrogen systems

    Energy Technology Data Exchange (ETDEWEB)

    Leppaenen, J. [Neste Oy/NAPS (Finland)

    1998-10-01

    PV systems are widely used in remote areas e.g. in telecommunication systems. Typically lead acid batteries are used as energy storage. In northern locations seasonal storage is needed, which however is too expensive and difficult to realise with batteries. Therefore, a PV- battery system with a diesel backup is sometimes used. The disadvantages of this kind of system for very remote applications are the need of maintenance and the need to supply the fuel. To overcome these problems, it has been suggested to use hydrogen technologies to make a closed loop autonomous energy storage system

  6. PV Systems Reliability Final Technical Report.

    Energy Technology Data Exchange (ETDEWEB)

    Lavrova, Olga [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Flicker, Jack David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Johnson, Jay [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Armijo, Kenneth Miguel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gonzalez, Sigifredo [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Schindelholz, Eric John [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sorensen, Neil R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Yang, Benjamin Bing-Yeh [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-12-01

    The continued exponential growth of photovoltaic technologies paves a path to a solar-powered world, but requires continued progress toward low-cost, high-reliability, high-performance photovoltaic (PV) systems. High reliability is an essential element in achieving low-cost solar electricity by reducing operation and maintenance (O&M) costs and extending system lifetime and availability, but these attributes are difficult to verify at the time of installation. Utilities, financiers, homeowners, and planners are demanding this information in order to evaluate their financial risk as a prerequisite to large investments. Reliability research and development (R&D) is needed to build market confidence by improving product reliability and by improving predictions of system availability, O&M cost, and lifetime. This project is focused on understanding, predicting, and improving the reliability of PV systems. The two areas being pursued include PV arc-fault and ground fault issues, and inverter reliability.

  7. PMBLDCG based stand-alone wind energy conversion system for ...

    African Journals Online (AJOL)

    International Journal of Engineering, Science and Technology. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 4, No 1 (2012) >. Log in or Register to get access to full text downloads.

  8. PMBLDCG based stand-alone wind energy conversion system for ...

    African Journals Online (AJOL)

    user

    David et al 2001, Simoes and Farret 2004,. Bhadra et al 2004, Ackermann 2005). The permanent magnet ..... David Sharpe Burton, Jenkins Nick and Bossanyi Ervin, 2001. “Wind Energy Handbook,” John Wiley & Sons. Ltd. Gieras J. F. and ...

  9. Rating PV Power and Energy: Cell, Module, and System Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Emery, Keith

    2016-06-02

    A summary of key points related to research-level measurements of current vs. voltage measurement theory including basic PV operation, equivalent circuit, and concept of spectral error; PV power performance including PV irradiance sensors, simulators and commercial and generic I-V systems; PV measurement artifacts, intercomparisons, and alternative rating methods.

  10. Design of an off-grid hybrid PV/wind power system for remote mobile base station: A case study

    Directory of Open Access Journals (Sweden)

    Mulualem T. Yeshalem

    2017-01-01

    Full Text Available There is a clear challenge to provide reliable cellular mobile service at remote locations where a reliable power supply is not available. So, the existing Mobile towers or Base Transceiver Station (BTSs uses a conventional diesel generator with backup battery banks. This paper presents the solution to utilizing a hybrid of photovoltaic (PV solar and wind power system with a backup battery bank to provide feasibility and reliable electric power for a specific remote mobile base station located at west arise, Oromia. All the necessary modeling, simulation, and techno-economic evaluation are carried out using Hybrid Optimization Model for Electric Renewable (HOMER software. The best optimal system configurations namely PV/Battery and PV/Wind/Battery hybrid systems are compared with the conventional stand-alone diesel generator (DG system. Findings indicated that PV array and battery is the most economically viable option with the total net present cost (NPC of $\\$$57,508 and per unit cost of electricity (COE of $\\$$0.355. Simulation results show that the hybrid energy systems can minimize the power generation cost significantly and can decrease CO2 emissions as compared to the traditional diesel generator only. The sensitivity analysis is also carried out to analysis the effects of probable variation in solar radiation, wind speed, diesel price and average annual energy usage of the system load in the optimal system configurations.

  11. Grid parity analysis of stand-alone hybrid microgrids: A comparative study of Germany, Pakistan, South Africa and the United States

    Science.gov (United States)

    Siddiqui, Jawad M.

    Grid parity for alternative energy resources occurs when the cost of electricity generated from the source is lower than or equal to the purchasing price of power from the electricity grid. This thesis aims to quantitatively analyze the evolution of hybrid stand-alone microgrids in the US, Germany, Pakistan and South Africa to determine grid parity for a solar PV/Diesel/Battery hybrid system. The Energy System Model (ESM) and NREL's Hybrid Optimization of Multiple Energy Resources (HOMER) software are used to simulate the microgrid operation and determine a Levelized Cost of Electricity (LCOE) figure for each location. This cost per kWh is then compared with two distinct estimates of future retail electricity prices at each location to determine grid parity points. Analysis results reveal that future estimates of LCOE for such hybrid stand-alone microgrids range within the 35-55 cents/kWh over the 25 year study period. Grid parity occurs earlier in locations with higher power prices or unreliable grids. For Pakistan grid parity is already here, while Germany hits parity between the years 2023-2029. Results for South Africa suggest a parity time range of the years 2040-2045. In the US, places with low grid prices do not hit parity during the study period. Sensitivity analysis results reveal the significant impact of financing and the cost of capital on these grid parity points, particularly in developing markets of Pakistan and South Africa. Overall, the study helps conclude that variations in energy markets may determine the fate of emerging energy technologies like microgrids. However, policy interventions have a significant impact on the final outcome, such as the grid parity in this case. Measures such as eliminating uncertainty in policies and improving financing can help these grids overcome barriers in developing economies, where they may find a greater use much earlier in time.

  12. Electrical integration of renewable energy into stand-alone power supplies incorporating hydrogen storage

    Energy Technology Data Exchange (ETDEWEB)

    Little, Matthew; Thomson, Murray

    2007-07-15

    A stand-alone renewable-energy system employing a hydrogen-based energy store is now being commissioned within the HaRI project at West Beacon Farm, Leicestershire, UK. The interconnection of the various generators, loads and storage system is made through a central DC busbar: an arrangement that is believed to be unique within systems of this type and scale. The rotating generators, such as the wind turbines, are connected through standard industrial drives operating in regenerative mode, while the DC devices - electrolyser, fuel cell and solar photovoltaic array - employ custom DC-DC converters. This paper reviews the design philosophy of the electrical system and the various converters required. Modelling and simulation of the system is discussed along with practical lessons learnt from its implementation and some initial results are presented. (author)

  13. Prioritized rule based load management technique for residential building powered by PV/battery system

    Directory of Open Access Journals (Sweden)

    T.R. Ayodele

    2017-06-01

    Full Text Available In recent years, Solar Photovoltaic (PV system has presented itself as one of the main solutions to the electricity poverty plaguing the majority of buildings in rural communities with solar energy potential. However, the stochasticity associated with solar PV power output owing to vagaries in weather conditions is a major challenge in the deployment of the systems. This study investigates approach for maximizing the benefits of a Stand-Alone Photovoltaic-Battery (SAPVB system via techniques that provide for optimum energy gleaning and management. A rule-based load management scheme is developed and tested for a residential building. The approach allows load prioritizing and shifting based on certain rules. To achieve this, the residential loads are classified into Critical Loads (CLs and Uncritical Loads (ULs. The CLs are given higher priority and therefore are allowed to operate at their scheduled time while the ULs are of less priority, hence can be shifted to a time where there is enough electric power generation from the PV arrays rather than the loads being operated at the time period set by the user. Four scenarios were created to give insight into the applicability of the proposed rule based load management scheme. The result revealed that when the load management technique is not utilized as in the case of scenario 1 (Base case, the percentage satisfaction of the critical and uncritical loads by the PV system are 49.8% and 23.7%. However with the implementation of the load management scheme in scenarios 2, 3 and 4, the percentage satisfaction of the loads (CLs, ULs are (93.8%, 74.2%, (90.9%, 70.1% and (87.2%, 65.4% for scenarios 2, 3 and 4, respectively.

  14. Updating Interconnection Screens for PV System Integration

    Energy Technology Data Exchange (ETDEWEB)

    Coddington, M.; Mather, B.; Kroposki, B.; Lynn, K.; Razon, A.; Ellis, A.; Hill, R.; Key, T.; Nicole, K.; Smith, J.

    2012-02-01

    This white paper evaluates the origins and usefulness of the capacity penetration screen, offer short-term solutions which could effectively allow fast-track interconnection to many PV system applications, and considers longer-term solutions for increasing PV deployment levels in a safe and reliable manner while reducing or eliminating the emphasis on the penetration screen. Short-term and longer-term alternatives approaches are offered as examples; however, specific modifications to screening procedures should be discussed with stakeholders and must ultimately be adopted by state and federal regulatory bodies.

  15. An Analysis of Stand-alone GPS Quality and Simulated GNSS Quality for Road Pricing

    DEFF Research Database (Denmark)

    Zabic, Martina; Nielsen, Otto Anker

    2006-01-01

    Use of GPS for road pricing has often been suggested as the way of creating more efficient charging strategies than existing systems based on cordon lines or time use. In Denmark, Copenhagen participated with the AKTA project in the PRoGRESS programme, sponsored by the EU. The major part...... of the AKTA project was to equip 500 cars with GPS receivers. The paper presents the methods and results from a study of GPS quality in relation to road pricing in a dense urban area. The collected data from 500 cars over a two-year period in the Copenhagen region was analyzed in order to determine whether...... the stand alone GPS quality and reliability is adequate for implementation of an operational road pricing system in Copenhagen. The results from the analysis show that the satellite availability in Copenhagen is not sufficient to form the basis for a reliable operational road pricing system. The narrow...

  16. Optimum Design Of On Grid Pv System Using Tracking System

    Directory of Open Access Journals (Sweden)

    Saeed Mansour

    2015-05-01

    Full Text Available Abstract The fossil fuel is a main issue in the world due to the increase of fossil fuel cost and the depletion of the fossil fuel with continuous increasing demand on electricity. With continuous decrease of PV panels cost it is interesting to consider generation of electricity from PV system. To provide electric energy to a load in a remote area where electric grid utility is not available or connection with grid utility is available there are two approaches of photovoltaic system PV without tracking system Fixed System and PV with tracking systems. The result shows that the energy production by using PV with tracking system generates more energy in comparison with fixed panels system. However the cost per produced KWH is less in case of using fixed panels. This is the backbone in choice between two approaches of photovoltaic system. In this work a system design and cost analysis for two approaches of photovoltaic system are considered.

  17. Lossy Data Aggregation with Network Coding in Stand-Alone Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Madsen, Tatiana Kozlova

    2011-01-01

    This work focuses on a special type of wireless sensor networks (WSNs) that we refer to as a stand alone network. These netwoks operate in harsh and extreme environments where data collection is done only occasionally. Typical examples include habitat monitoring systems, monitoring systems...... in chemical plants, etc. Given resource constrained operation of a sensor network where the nodes are battery powered and buffer sizes are limited, efficient methods for in-network data storage abd it subsequent fast and reliable transmission to a gateway is desirable. To save scarse resources and to prolong...... the lifetime of the whole network, the lossy data grregation method can be applied. It is especially viable in the networks where several sensors are measuring the same physical phenomenum and only average values of sensor readings are of interest. In this paper we present a method for efficient lossy data...

  18. Stand-alone version of the 11kW Gaia wind turbine

    Energy Technology Data Exchange (ETDEWEB)

    Bindner, H.; Rosas, P.A.C.; Teodorescu, R.; Blaabjerg, F.

    2004-09-15

    This report describes the development of a stand-alone version of the 11kW Gaia wind turbine. Various possible configurations are investigated and a configuration using a back-to-back converter is chosen. A model is developed for controller design of the fast controllers of the unit. Controllers are designed and a prototype is built for testing. The report documents the performance of the prototype through measurements done on the full scale prototype installed in a test facility where it has been tested both as a standalone unit and in parallel with a diesel genset. For system wide power quality assessment and controller design a dynamic performance assessment model has been developed. (au)

  19. Flexible Control of Small Wind Turbines With Grid Failure Detection Operating in Stand-Alone and Grid-Connected Mode

    DEFF Research Database (Denmark)

    Teodorescu, Remus; Blaabjerg, Frede

    2004-01-01

    This paper presents the development and test of a flexible control strategy for an 11-kw wind turbine with a back-to-back power converter capable of working in both stand-alone and grid-connected mode. The stand-alone control is featured with a complex output voltage controller capable of handling...... nonlinear load and excess or deficit of generated power. Grid-connection mode with current control is also enabled for the case of isolated local grid involving other dispersed power generators such as other wind turbines or diesel generators. A novel automatic mode switch method based on a phase......-locked loop controller is developed in order to detect the grid failure or recovery and switch the operation mode accordingly. A flexible digital signal processor (DSP) system that allows user-friendly code development and on-line tuning is used to implement and test the different control strategies. The back...

  20. Diagnostic value of the stand-alone synthetic image in digital breast tomosynthesis examinations.

    Science.gov (United States)

    Garayoa, Julia; Chevalier, Margarita; Castillo, Maria; Mahillo-Fernández, Ignacio; Amallal El Ouahabi, Najim; Estrada, Carmen; Tejerina, Alejandro; Benitez, Olivia; Valverde, Julio

    2018-02-01

    To demonstrate the non-inferiority of synthetic image (SI) mammography versus full-field digital mammography (FFDM) in breast tomosynthesis (DBT) examinations. An observational, retrospective, single-centre, multireader blinded study was performed, using 2384 images to directly compare SI and FFDM based on Breast Imaging Reporting and Data System (BIRADS) categorisation and visibility of radiological findings. Readers had no access to digital breast tomosynthesis slices. Multiple reader, multiple case (MRMC) receiver operating characteristic (ROC) methodology was used to compare the diagnostic performance of SI and FFDM images. The kappa statistic was used to estimate the inter-reader and intra-reader reliability. The area under the ROC curves (AUC) reveals the non-inferiority of SI versus FFDM based on BIRADS categorisation [difference between AUC (ΔAUC), -0.014] and lesion visibility (ΔAUC, -0.001) but the differences were not statistically significant (p=0.282 for BIRADS; p=0.961 for lesion visibility). On average, 77.4% of malignant lesions were detected with SI versus 76.5% with FFDM. Sensitivity and specificity of SI are superior to FFDM for malignant lesions scored as BIRADS 5 and breasts categorised as BIRADS 1. SI is not inferior to FFDM when DBT slices are not available during image reading. SI can replace FFDM, reducing the dose by 45%. • Stand-alone SI demonstrated performance not inferior for lesion visibility as compared to FFDM. • Stand-alone SI demonstrated performance not inferior for lesion BIRADS categorisation as compared to FFDM. • Synthetic images provide important dose savings in breast tomosynthesis examinations.

  1. Fault Detection and Performance Monitoring in PV Systems

    OpenAIRE

    Vasco Brogueira Andrade

    2017-01-01

    Given the exponential growth of the PV sector in recent years and the market?s overall need for new PV monitoring solutions, this dissertation aims at creating an automatic fault detection tool for PV systems, more specifically for shading and soiling situations. By detecting deviations in the measured PV systems? data patterns, this tool aims at providing essential information for the deployment of the right maintenance strategy for each situation.

  2. The possibility of developing hybrid PV/T solar system

    Science.gov (United States)

    Dobrnjac, M.; Zivkovic, P.; Babic, V.

    2017-05-01

    An alternative and cost-effective solution to developing integrated PV system is to use hybrid photovoltaic/thermal (PV/T) solar system. The temperature of PV modules increases due to the absorbed solar radiation that is not converted into electricity, causing a decrease in their efficiency. In hybrid PV/T solar systems the reduction of PV module temperature can be combined with a useful fluid heating. In this paper we present the possibility of developing a new hybrid PV/T solar system. Hybrid PV/T system can provide electrical and thermal energy, thus achieving a higher energy conversion rate of the absorbed solar radiation. We developed PV/T prototype consisted of commercial PV module and thermal panel with our original solution of aluminium absorber with special geometric shapes. The main advantages of our combined PV/T system are: removing of heat from the PV panel; extending the lifetime of photovoltaic cells; excess of the removing heat from PV part is used to heat the fluid in the thermal part of the panel; the possibility of using on the roof and facade constructions because less weight.

  3. Hybrid PV system with mini-grid in the rural area of Ginostra

    Energy Technology Data Exchange (ETDEWEB)

    Minissale, F.; Viglianesi, G.; Catena, M. [ENEL, Catania (Italy)

    2004-07-01

    ENEL, the Italian Electric facility, carried-out the realisation of a Hybrid plant in Ginostra, an isolated village of Stromboli Island, to comply with the specific needs of the residents, taking into account the available energy resources and the prescription of the Sicilian Environmental Department for the Aeolian Islands. The plant consists in a stand-alone system feeding an isolated electric mini-grid that is developed for about 2 km to reach all the village houses even the most remote ones. The specific peculiarity of Ginostra village is a high variability in the residents' number: about 50 people in winter and approximately 600 during July and August. So as to reach a best exploitation of the production capacity of the plant, a desalination system will be realised in a second time and it will constitute a periodical load to store water during the low occupation period (winter) and cover the demand in the summer. The plant realisation, financed by the Sicilian Regional Administration with 2,8 Million EUR, has started on July 2003 and its completion was on February 2004. Also the works for the mini grid realisation were completed for that period. The plant is already in operation. ENEL performed the design and the realisation of the PV-diesel Plant, putting it in running condition and for the following seven years will supply the plant normal operation, assuming the burdens of the system ordinary maintenance. The visual impact of the plant and of its support infrastructures are rather reduced, thanks to the selected position, visible only from mainland and from few areas. To such aim the typical plants of the Mediterranean bush, present in the PV-plant area, have been preserved in a nearby land, so as to be able to be put back again around to the PV-plant area in order to reduce its visual impact. (orig.)

  4. PV System Component Fault and Failure Compilation and Analysis.

    Energy Technology Data Exchange (ETDEWEB)

    Klise, Geoffrey Taylor; Lavrova, Olga; Gooding, Renee Lynne

    2018-02-01

    This report describes data collection and analysis of solar photovoltaic (PV) equipment events, which consist of faults and fa ilures that occur during the normal operation of a distributed PV system or PV power plant. We present summary statistics from locations w here maintenance data is being collected at various intervals, as well as reliability statistics gathered from that da ta, consisting of fault/failure distributions and repair distributions for a wide range of PV equipment types.

  5. Methanol production via pressurized entrained flow biomass gasification – Techno-economic comparison of integrated vs. stand-alone production

    International Nuclear Information System (INIS)

    Andersson, Jim; Lundgren, Joakim; Marklund, Magnus

    2014-01-01

    The main objective with this work was to investigate techno-economically the opportunity for integrated gasification-based biomass-to-methanol production in an existing chemical pulp and paper mill. Three different system configurations using the pressurized entrained flow biomass gasification (PEBG) technology were studied, one stand-alone plant, one where the bark boiler in the mill was replaced by a PEBG unit and one with a co-integration of a black liquor gasifier operated in parallel with a PEBG unit. The cases were analysed in terms of overall energy efficiency (calculated as electricity-equivalents) and process economics. The economics was assessed under the current as well as possible future energy market conditions. An economic policy support was found to be necessary to make the methanol production competitive under all market scenarios. In a future energy market, integrating a PEBG unit to replace the bark boiler was the most beneficial case from an economic point of view. In this case the methanol production cost was reduced in the range of 11–18 Euro per MWh compared to the stand-alone case. The overall plant efficiency increased approximately 7%-units compared to the original operation of the mill and the non-integrated stand-alone case. In the case with co-integration of the two parallel gasifiers, an equal increase of the system efficiency was achieved, but the economic benefit was not as apparent. Under similar conditions as the current market and when methanol was sold to replace fossil gasoline, co-integration of the two parallel gasifiers was the best alternative based on received IRR. - Highlights: • Techno-economic results regarding integration of methanol synthesis processes in a pulp and paper mill are presented. • The overall energy efficiency increases in integrated methanol production systems compared to stand-alone production units. • The economics of the integrated system improves compared to stand-alone alternatives. • Tax

  6. Integrating Solar PV in Utility System Operations

    Energy Technology Data Exchange (ETDEWEB)

    Mills, A.; Botterud, A.; Wu, J.; Zhou, Z.; Hodge, B-M.; Heany, M.

    2013-10-31

    This study develops a systematic framework for estimating the increase in operating costs due to uncertainty and variability in renewable resources, uses the framework to quantify the integration costs associated with sub-hourly solar power variability and uncertainty, and shows how changes in system operations may affect these costs. Toward this end, we present a statistical method for estimating the required balancing reserves to maintain system reliability along with a model for commitment and dispatch of the portfolio of thermal and renewable resources at different stages of system operations. We estimate the costs of sub-hourly solar variability, short-term forecast errors, and day-ahead (DA) forecast errors as the difference in production costs between a case with “realistic” PV (i.e., subhourly solar variability and uncertainty are fully included in the modeling) and a case with “well behaved” PV (i.e., PV is assumed to have no sub-hourly variability and can be perfectly forecasted). In addition, we highlight current practices that allow utilities to compensate for the issues encountered at the sub-hourly time frame with increased levels of PV penetration. In this analysis we use the analytical framework to simulate utility operations with increasing deployment of PV in a case study of Arizona Public Service Company (APS), a utility in the southwestern United States. In our analysis, we focus on three processes that are important in understanding the management of PV variability and uncertainty in power system operations. First, we represent the decisions made the day before the operating day through a DA commitment model that relies on imperfect DA forecasts of load and wind as well as PV generation. Second, we represent the decisions made by schedulers in the operating day through hour-ahead (HA) scheduling. Peaking units can be committed or decommitted in the HA schedules and online units can be redispatched using forecasts that are improved

  7. Interharmonics from Grid-Connected PV Systems

    DEFF Research Database (Denmark)

    Sangwongwanich, Ariya; Yang, Yongheng; Sera, Dezso

    2017-01-01

    As the penetration level of grid-connected Photovoltaic (PV) systems increases, the power quality is one of the major concerns for system operators and the demands are becoming even stricter. The impact of interharmonics on the grid has been acknowledged in recent research when considering a large...... of the Maximum Power Point Tracking (MPPT) algorithm is one of the sources that induce interharmonics in the grid current, especially at low-power operating conditions. Accordingly, three mitigation solutions are discussed to address this issue, and simulations have been carried out to verify the effectiveness...

  8. Key factors for the implementation of successful, stand-alone village electrification schemes in Peru

    Science.gov (United States)

    Sanchez-Campos, Teodoro

    The hypothesis of this work is that there are social, financial, technical, managerial institutional and political key factors that may either support or prevent the success of small stand alone energy systems in rural areas. This research work aims at contributing to the identification of such factors and study their relevance to the performance and sustainability of stand alone energy systems in rural areas; to meet its purpose, a wide range of literature was reviewed including rural electrification programmes and projects, research and development projects on access to electricity in rural areas, impact studies and others, and a field research survey was done the Andes and Upper Jungle regions in Peru. Nineteen possible critical factors were identified, thirteen with relevance at the local context (the community or village), and six with relevance at the national (or wider) context. From literature review it was found that the possible local critical factors were relevant only to four categories of factors instead of the six considered initially (i.e. social, financial, technological and managerial): the other two categories, political and institutional were found to be more relevant to the national context, therefore those were included in the group of possible critical factors of wider context. A series of questionnaires were designed to collect field data information, which was later used to analyse and establish the relation of each identified factor with the success of the systems studied. The survey research was implemented in 14 villages, 7 with small diesel sets and 7 with small hydropower schemes, all spread in the Andes and Upper Jungle of Peru, which were carefully selected to be representative of regions with isolated stand alone systems and with different socioeconomic background. Out of the 13 possible critical factors of local context, it was found that only 3 are really critical, the others are important but not critical; one of them (technical

  9. Commercialization of PV-powered pumping systems for use in utility PV service programs. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The project described in this report was a commercialization effort focused on cost-effective remote water pumping systems for use in utility-based photovoltaic (PV) service programs. The project combined a commercialization strategy tailored specifically for electric utilities with the development of a PV-powered pumping system that operates conventional ac pumps rather than relying on the more expensive and less reliable PV pumps on the market. By combining these two attributes, a project goal was established of creating sustained utility purchases of 250 PV-powered water pumping systems per year. The results of each of these tasks are presented in two parts contained in this Final Summary Report. The first part summarizes the results of the Photovoltaic Services Network (PSN) as a new business venture, while the second part summarizes the results of the Golden Photon system installations. Specifically, results and photographs from each of the system installations are presented in this latter part.

  10. Optimization of an off-grid hybrid PV-wind-diesel-battery system

    Energy Technology Data Exchange (ETDEWEB)

    Merei, Ghada [RWTH Aachen Univ. (Germany). Electrochemical Energy Conversion and Storage Systems Group; Juelich Aachen Research Alliance, JARA-Energy (Germany); Sauer, Dirk Uwe [RWTH Aachen Univ. (Germany). Electrochemical Energy Conversion and Storage Systems Group; Juelich Aachen Research Alliance, JARA-Energy (Germany); RWTH Aachen Univ. (Germany). Inst. for Power Generation and Storage Systems (PGS)

    2012-07-01

    The power supply of remote sites and applications at minimal cost and with low emissions is an important issue when discussing future energy concepts. This paper presents the modelling and optimisation of a stand-alone hybrid energy system. The system consists of photovoltaic (PV) panels and a wind turbine as renewable power sources, a diesel generator for back-up power and batteries to store excess energy and to improve the system reliability. For storage the technologies of lithium-ion, lead-acid, vanadium redox-flow or a combination thereof are considered. In order to use different battery technologies at once, a battery management system (BMS) is needed. The presented BMS minimises operation cost while taking into account different battery operating points and ageing mechanisms. The system is modelled and implemented in Matlab/Simulink. As input, the model uses data of the irradiation, wind speed and air temperature measured in ten minute intervals for ten years in Aachen, Germany. The load is assumed to be that of a rural UMTS/GSM base station for telecommunication. For a timeframe of 20 years, the performance is evaluated and the total costs are determined. Using a genetic algorithm, component sizes and settings are then varied and the system re-evaluated to minimise the overall cost. The optimisation results show that using batteries in combination with the renewables is economic and ecologic. However, the best solution is to combine redox-flow batteries with the renewables. In addition, a power supply system consisting only of batteries, PV and wind generators can satisfy the power demand.

  11. Optimal design of PV and HP system

    DEFF Research Database (Denmark)

    Nepper-Rasmussen, Bjarke Christian; Rasmussen, Theis Bo

    2015-01-01

    electric energy demand of the HP to hours where excess PV power is present. The self-consumption of the PV energy affects the overall net present value (NPV). In this paper, a method which maximizes the NPV by finding the cost-optimal combination of PV, HP and BT sizes, is proposed. Results show......Methods of utilizing residential produced photovoltaic (PV) power by converting to thermal energy through heat pumps (HP) are present in literature, where thermal energy is dispersed as either heat or hot water at the instant moment of PV production. In this paper an alternative solution...

  12. She stands alone: Pakistani woman film director, Shireen Pasha.

    Science.gov (United States)

    Mustafa, A

    1995-01-01

    This article describes the activities of film director Shireen Pasha in promoting truth in the mass media in Pakistan. Pasha is described as one who finds it inexcusable in a state-subsidized system that national problems of poverty are not aired openly. Pasha has pursued the goal of exposing the real lives of Pakistanis on film in contrast to the publicly aired segments of "pretty girls in nice drawing rooms." Foreign channels available through satellite communications technology are viewed by Pasha as inappropriate with regard to people's needs and uncreative. Pakistan began with one channel, PTV, which recently refused to air her documentary on living conditions in Pakistan's rural areas "The Travelogue Pakistan." "The Walled City of Lahore" was her film about life in the old city. Both films poetically depicted the honor of humans and their struggle to stay alive. Some of her documentaries are made to show the value of indigenous skills, centuries old know-how, and traditions, regardless of the poverty. Pasha is described as fighting with PTV management over use of resources. Pasha desires to invest in training people to do documentaries or be more field-oriented rather than investing in equipment. Pasha joined PTV in 1975 and left in 1990. Pasha is recognized for her isolation as a woman in the business world, her commitment to exposing remote cultures and truth, and the odds she must confront in attaining her goals. Pasha is committed to doing extensive research, usually conducted during the summer months, in order to construct a credible story line that is produced usually during the winter months. One model of film story line is defined as one where women are portrayed as starting from an indigenous skill or knowledge and shifting to a greater position of power and control over their lives. Pasha believes that people who make films have the responsibility to evoke a reaction in people and to offer solutions. Two acclaimed films, which were supported by

  13. An optimized Fuzzy Logic Controller by Water Cycle Algorithm for power management of Stand-alone Hybrid Green Power generation

    International Nuclear Information System (INIS)

    Sarvi, Mohammad; Avanaki, Isa Nasiri

    2015-01-01

    Highlights: • A new method to improve the performance of renewable power management is proposed. • The proposed method is based on Fuzzy Logic optimized by the Water Cycle Algorithm. • The proposed method characteristics are compared with two other methods. • The comparisons confirm that the proposed method is robust and effectiveness one. - Abstract: This paper aims to improve the power management system of a Stand-alone Hybrid Green Power generation based on the Fuzzy Logic Controller optimized by the Water Cycle Algorithm. The proposed Stand-alone Hybrid Green Power consists of wind energy conversion and photovoltaic systems as primary power sources and a battery, fuel cell, and Electrolyzer as energy storage systems. Hydrogen is produced from surplus power generated by the wind energy conversion and photovoltaic systems of Stand-alone Hybrid Green Power and stored in the hydrogen storage tank for fuel cell later using when the power generated by primary sources is lower than load demand. The proposed optimized Fuzzy Logic Controller based power management system determines the power that is generated by fuel cell or use by Electrolyzer. In a hybrid system, operation and maintenance cost and reliability of the system are the important issues that should be considered in studies. In this regard, Water Cycle Algorithm is used to optimize membership functions in order to simultaneously minimize the Loss of Power Supply Probability and operation and maintenance. The results are compared with the particle swarm optimization and the un-optimized Fuzzy Logic Controller power management system to prove that the proposed method is robust and effective. Reduction in Loss of Power Supply Probability and operation and maintenance, are the most advantages of the proposed method. Moreover the level of the State of Charge of the battery in the proposed method is higher than other mentioned methods which leads to increase battery lifetime.

  14. EXPERIMENTAL ANALYSIS OF THE CHARACTERISTIC PERFORMANCE OF STANDALONE PHOTOVOLTAIC SYSTEM

    OpenAIRE

    Birendra Kishore; Anirban Nandy*; O.P. Pandey

    2016-01-01

    This paper demonstrates an insight solar PV Stand Alone system which is a practical model with a halogen light source. At different situations the performance of solar PV cells are analyzed. The system produces power with depending on the change in halogen light intensity & temperature. A theoretical & experimental analysis of the PV cell can be achieved. In this paper the I-V & P-V characteristic of the solar photovoltaic cells with changes in temperature and isolation have been showed. With...

  15. Design of a reliable and low-cost stand-alone micro hydropower station

    Energy Technology Data Exchange (ETDEWEB)

    Kusakana, K.; Munda, J.L. [Tshwane Univ. of Technology, Pretoria (South Africa)

    2008-07-01

    A stand-alone micro-hydropower station was presented. The plant was comprised of a squirrel cage induction machine coupled to a Kaplan water turbine. Power converters were used to control the variable frequency and voltage outputs of the generator caused by variations in water flow. The hydropower plant was installed a farm in the Kwazulu-Natal region of South Africa, and was designed to provide electricity in relation to the low power demand of users in the region as well as according to the site's hydrology and topology. Load forecasts for the 8 houses using the system were conducted. A generator with a higher output than the average power needed to feed the load was selected in order to ensure load supply during peak demand. The system was designed to shore energy generated during off-peak periods in batteries. An AC-DC-AC converter was used as an interface between the generator and the load in order to ensure voltage and frequency stabilization. Simulations of plant components were conducted to demonstrate output power supply during water flow variations. Results of the modelling study indicated that power converters are needed to stabilize generator outputs. The hydropower design is a cost-effective means of supplying power to low-income households. 10 refs., 2 tabs., 7 figs.

  16. Stand-alone excitation synchronous wind power generators with power flow management strategy

    Directory of Open Access Journals (Sweden)

    Tzuen-Lih Chern

    2014-09-01

    Full Text Available This study presents a stand-alone excitation synchronous wind power generator (SESWPG with power flow management strategy (PFMS. The rotor speed of the excitation synchronous generator tracks the utility grid frequency by using servo motor tracking technologies. The automatic voltage regulator governs the exciting current of generator to achieve the control goals of stable voltage. When wind power is less than the needs of the consumptive loading, the proposed PFMS increases motor torque to provide a positive power output for the loads, while keeping the generator speed constant. Conversely, during the periods of wind power greater than output loads, the redundant power of generator production is charged to the battery pack and the motor speed remains constant with very low power consumption. The advantage of the proposed SESWPG is that the generator can directly output stable alternating current (AC electricity without using additional DC–AC converters. The operation principles with software simulation for the system are described in detail. Experimental results of a laboratory prototype are shown to verify the feasibility of the system.

  17. Integrated versus stand-alone second generation ethanol production from sugarcane bagasse and trash.

    Science.gov (United States)

    Dias, Marina O S; Junqueira, Tassia L; Cavalett, Otávio; Cunha, Marcelo P; Jesus, Charles D F; Rossell, Carlos E V; Maciel Filho, Rubens; Bonomi, Antonio

    2012-01-01

    Ethanol production from lignocellulosic materials is often conceived considering independent, stand-alone production plants; in the Brazilian scenario, where part of the potential feedstock (sugarcane bagasse) for second generation ethanol production is already available at conventional first generation production plants, an integrated first and second generation production process seems to be the most obvious option. In this study stand-alone second generation ethanol production from surplus sugarcane bagasse and trash is compared with conventional first generation ethanol production from sugarcane and with integrated first and second generation; simulations were developed to represent the different technological scenarios, which provided data for economic and environmental analysis. Results show that the integrated first and second generation ethanol production process from sugarcane leads to better economic results when compared with the stand-alone plant, especially when advanced hydrolysis technologies and pentoses fermentation are included. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Can aqueous hydrogen peroxide be used as a stand-alone energy source?

    International Nuclear Information System (INIS)

    Disselkamp, Robert S.

    2010-01-01

    A novel electrochemical scheme to convert a stand-alone supply of aqueous hydrogen peroxide into a fuel cell-ready stream of hydrogen gas plus aqueous hydrogen peroxide is described. The electrochemical cell, consisting of a solid base and solid acid electrocatalyst, together with a proton exchange membrane, comprise the system that converts aqueous hydrogen peroxide into separate gas streams of oxygen and hydrogen. Aqueous hydrogen peroxide is contained in the anode compartment only and exists in the region where oxygen gas is formed, whereas the cathode compartment is where hydrogen gas is generated and therefore exists in a reduced state. A near zero theoretical over-potential can be achieved by the choice of basicity and acidity of the electrode materials. The primary cost of the electrochemical cell is electrode construction and the aqueous hydrogen peroxide energy storage compound. Additional research effort is required to experimentally validate the concept and explore the full economic impact should initial studies, based on the design presented here, prove promising. (author)

  19. Assessment of Stand-Alone Displays for Time Management in a Creativity-Driven Learning Environment

    DEFF Research Database (Denmark)

    Frimodt-Møller, Søren

    2017-01-01

    This paper considers the pros and cons of stand-alone displays, analog (e.g. billboards, blackboards, whiteboards, large pieces of paper etc.) as well as digital (e.g. large shared screens, digital whiteboards or similar), as tools for time management processes in a creativity-driven learning...... to storing information digitally. The findings could indicate a possible market for stand-alone, interactive digital displays combining the ‘touch and feel’ character of an analog board with the convenience of digital data storage....

  20. Dynamic behavior of PEM FCPPs under various load conditions and voltage stability analysis for stand-alone residential applications

    Science.gov (United States)

    Uzunoglu, M.; Onar, O. C.; Alam, M. S.

    In this paper, dynamic behavior and performance of a fuel cell power plant (FCPP) which operates in parallel with a battery bank is tested under classified load conditions, such as mostly resistive, mostly inductive, resistive-inductive and non-linear loads. Thereafter, voltage stability analysis is performed using the dynamic response of the FCPP for stand-alone residential applications. Simulation results are obtained using the MATLAB ® and Simulink ® software packages, based on the mathematical and dynamic electrical models of the system. Using the experimental results, a validated model has been realized and voltage stability analysis is performed through this model.

  1. PV Obelisk - Information system with photovoltaics; PV-Obelisk Orientierungssystem mit Photovoltaik

    Energy Technology Data Exchange (ETDEWEB)

    Ruoss, D.; Rasmussen, J.

    2004-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) describes the development of an information system powered by a photovoltaic (PV) array. As an innovative approach, the 'PV-Obelisk' project is the combination of PV with a multi-functional pillar made of natural stone in an aesthetic way. The PV modules serve both as a power supply and as a design element. Two initial prototypes led the way to a third, optimised consumer configuration that was planned to guarantee maximum user frequency. Test operation in front of the 'Heidiland' motor way restaurant confirmed the market analyses made and delivered the expected results. The product, whose three LCD displays are updated via a mobile telephony-based text-message system, proved its technical reliability and showed a high user frequency. Because of the high overall energy consumption, PV power can only partially contribute to the energy supply needed. Various compromises in the technical and aesthetic areas are discussed that were made for the sake of product acceptance in the market. The range of application areas for such a 'PV Obelisk' are discussed and the need for early co-ordination with urban planners is stressed.

  2. System and Battery Charge Control for PV-Powered AC Lighting Systems

    Energy Technology Data Exchange (ETDEWEB)

    Kern, G.

    1999-04-01

    This report reviews a number of issues specific to stand-alone AC lighting systems. A review of AC lighting technology is presented, which discusses the advantages and disadvantages of various lamps. The best lamps for small lighting systems are compact fluorescent. The best lamps for intermediate-size systems are high- or low-pressure sodium. Specifications for battery charging and load control are provided with the goal of achieving lamp lifetimes on the order of 16,000 to 24,000 hours and battery lifetimes of 4 to 5 years. A rough estimate of the potential domestic and global markets for stand-alone AC lighting systems is presented. DC current injection tests were performed on high-pressure sodium lamps and the test results are presented. Finally, a prototype system was designed and a prototype system controller (with battery charger and DC/AC inverter) was developed and built.

  3. Linguistic and Structural Analyses of Stand-Alone Literature Reviews: Seventy-Five Years of Change

    Science.gov (United States)

    Wright, Heidi Rachel

    2016-01-01

    The purpose of this dissertation is to offer a multifaceted overview of stand-alone literature reviews. These texts, literature reviews published unattached to research articles, have existed for centuries but remained largely unstudied by linguists. Thus, the goal of this project is to present these reviews' situational, grammatical, and…

  4. Clinical outcome of stand-alone ALIF compared to posterior instrumentation for degenerative disc disease

    DEFF Research Database (Denmark)

    Udby, Peter M.; Bech-Azeddine, Rachid

    2015-01-01

    low back pain resulting from degenerative disc disease. ALIF surgery has previously been linked with certain high risk complications and unfavorable long term fusion results. Newer studies suggest that stand-alone ALIF can possibly be advantageous compared to other types of posterior instrumented...

  5. Stand-alone version of the 11kW Gaia wind turbine

    DEFF Research Database (Denmark)

    Bindner, H.; Rosas, P.A.C.; Teodorescu, R.

    2004-01-01

    This report describes the development of a stand-alone version of the 11kW Gaia wind turbine. Various possible configurations are investigated and a configuration using a back-to-back converter is chosen. A model is developed for controller design of thefast controllers of the unit. Controllers...... assessment and controller design a dynamic performance assessment model has been developed....

  6. Analysis and controller design for stand-alone VSIs in synchronous reference frame

    DEFF Research Database (Denmark)

    Ramezani, Malek; Li, Shuhui; Golestan, Saeed

    2017-01-01

    The common practice for controlling the stand-alone voltage source inverters (VSIs) is to transform abc voltage and current signals to DC signals using the dq transformation, which makes it possible to control the new DC voltage and current signals just using simple proportional-integral controll...

  7. environmental/climatic effect on stand-alone solar energy supply

    African Journals Online (AJOL)

    climatic and environmental effects on PV system. A discussion of results obtained from simulations is also ... dant solar energy available throughout the year with reserve estimate of 3.5 - 7.0 kW/m2/day [1]. In order to ... based MPPT method [4], fractional open-circuit. Nigerian Journal of Technology. Vol. 31, No. 1, March ...

  8. Comparison of pulp-mill-integrated hydrogen production from gasified black liquor with stand-alone production from gasified biomass

    International Nuclear Information System (INIS)

    Andersson, E.; Harvey, S.

    2007-01-01

    When gasified black liquor is used for hydrogen production, significant amounts of biomass must be imported. This paper compares two alternative options for producing hydrogen from biomass: (A) pulp-mill-integrated hydrogen production from gasified back liquor; and (B) stand-alone production of hydrogen from gasified biomass. The comparison assumes that the same amount of biomass that is imported in Alternative A is supplied to a stand-alone hydrogen production plant and that the gasified black liquor in Alternative B is used in a black liquor gasification combined cycle (BLGCC) CHP unit. The comparison is based upon equal amounts of black liquor fed to the gasifier, and identical steam and power requirements for the pulp mill. The two systems are compared on the basis of total CO 2 emission consequences, based upon different assumptions for the reference energy system that reflect different societal CO 2 emissions reduction target levels. Ambitions targets are expected to lead to a more CO 2 -lean reference energy system, in which case hydrogen production from gasified black liquor (Alternative A) is best from a CO 2 emissions' perspective, whereas with high CO 2 emissions associated with electricity production, hydrogen from gasified biomass and electricity from gasified black liquor (Alternative B) is preferable. (author)

  9. Parallel experimental study of a novel super-thin thermal absorber based photovoltaic/thermal (PV/T) system against conventional photovoltaic (PV) system

    OpenAIRE

    Peng Xu; Xingxing Zhang; Jingchun Shen; Xudong Zhao; Wei He; Deying Li

    2015-01-01

    Photovoltaic (PV) semiconductor degrades in performance due to temperature rise. A super thin-conductive thermal absorber is therefore developed to regulate the PV working temperature by retrofitting the existing PV panel into the photovoltaic/thermal (PV/T) panel. This article presented the parallel comparative investigation of the two different systems through both laboratory and field experiments. The laboratory evaluation consisted of one PV panel and one PV/T panel respectively while the...

  10. Interconnection of inverter dominated PV-hybrid systems; Vernetzung stromrichterdominierter PV-Hybridsysteme

    Energy Technology Data Exchange (ETDEWEB)

    Landau, M.; Engler, A.; Geipel, R.; Strauss, P. [Institut fuer Solare Energieversorgungstechnik (ISET), Kassel (Germany); Heinzemann, T.; Rothert, M. [SMA System-, Mess- und Anlagentechnik - Regelsysteme GmbH, Niestetal (Germany)

    2004-07-01

    In the bay of Gaidouromandra on the Greek island of Kythnos two three phase power supply systems were set up and operated within the frame of two European projects from 2000 to 2001. One is a PV-battery system and the other one is a PV-battery-diesel system. A speciality of both systems is the distributed PV-generation with the solar panels and PV-inverters (Sunny Boy {sup registered}) installed on the properties of several inhabitants. With the combination of both supply systems and changing the grid topology from three to single phase operation the problems further developments and a lot of system advantages could be demonstrated. The implementation of the new SELFSYNC {sup registered} multi master control method resulted in further improvement concerning available peak power and system reliability. In June 2003 the two three phase supply systems were converted into one single phase system. First operation experience is available and reported on. It is shown, that a suitable grid topology and interconnection result in advantages for the overall supply system. The benefits of the parallel operation of three Sunny Island {sup registered} battery inverters on a single phase are: (1) less inverters necessary, (2) lower idle consumption of the overall system, (3) increased power of the single phase and (4) redundancy. (orig.)

  11. Three junction holographic micro-scale PV system

    Science.gov (United States)

    Wu, Yuechen; Vorndran, Shelby; Ayala Pelaez, Silvana; Kostuk, Raymond K.

    2016-09-01

    In this work a spectrum splitting micro-scale concentrating PV system is evaluated to increase the conversion efficiency of flat panel PV systems. In this approach, the dispersed spectrum splitting concentration systems is scaled down to a small size and structured in an array. The spectrum splitting configuration allows the use of separate single bandgap PV cells that increase spectral overlap with the incident solar spectrum. This results in an overall increase in the spectral conversion efficiency of the resulting system. In addition other benefits of the micro-scale PV system are retained such reduced PV cell material requirements, more versatile interconnect configurations, and lower heat rejection requirements that can lead to a lower cost system. The system proposed in this work consists of two cascaded off-axis holograms in combination with a micro lens array, and three types of PV cells. An aspherical lens design is made to minimize the dispersion so that higher concentration ratios can be achieved for a three-junction system. An analysis methodology is also developed to determine the optical efficiency of the resulting system, the characteristics of the dispersed spectrum, and the overall system conversion efficiency for a combination of three types of PV cells.

  12. Optimized design and control of an off grid solar PV/hydrogen fuel cell power system for green buildings

    Science.gov (United States)

    Ghenai, C.; Bettayeb, M.

    2017-11-01

    Modelling, simulation, optimization and control strategies are used in this study to design a stand-alone solar PV/Fuel Cell/Battery/Generator hybrid power system to serve the electrical load of a commercial building. The main objective is to design an off grid energy system to meet the desired electric load of the commercial building with high renewable fraction, low emissions and low cost of energy. The goal is to manage the energy consumption of the building, reduce the associate cost and to switch from grid-tied fossil fuel power system to an off grid renewable and cleaner power system. Energy audit was performed in this study to determine the energy consumption of the building. Hourly simulations, modelling and optimization were performed to determine the performance and cost of the hybrid power configurations using different control strategies. The results show that the hybrid off grid solar PV/Fuel Cell/Generator/Battery/Inverter power system offers the best performance for the tested system architectures. From the total energy generated from the off grid hybrid power system, 73% is produced from the solar PV, 24% from the fuel cell and 3% from the backup Diesel generator. The produced power is used to meet all the AC load of the building without power shortage (hybrid power system produces 18.2% excess power that can be used to serve the thermal load of the building. The proposed hybrid power system is sustainable, economically viable and environmentally friendly: High renewable fraction (66.1%), low levelized cost of energy (92 /MWh), and low carbon dioxide emissions (24 kg CO2/MWh) are achieved.

  13. The eBioKit, a stand-alone educational platform for bioinformatics.

    Science.gov (United States)

    Hernández-de-Diego, Rafael; de Villiers, Etienne P; Klingström, Tomas; Gourlé, Hadrien; Conesa, Ana; Bongcam-Rudloff, Erik

    2017-09-01

    Bioinformatics skills have become essential for many research areas; however, the availability of qualified researchers is usually lower than the demand and training to increase the number of able bioinformaticians is an important task for the bioinformatics community. When conducting training or hands-on tutorials, the lack of control over the analysis tools and repositories often results in undesirable situations during training, as unavailable online tools or version conflicts may delay, complicate, or even prevent the successful completion of a training event. The eBioKit is a stand-alone educational platform that hosts numerous tools and databases for bioinformatics research and allows training to take place in a controlled environment. A key advantage of the eBioKit over other existing teaching solutions is that all the required software and databases are locally installed on the system, significantly reducing the dependence on the internet. Furthermore, the architecture of the eBioKit has demonstrated itself to be an excellent balance between portability and performance, not only making the eBioKit an exceptional educational tool but also providing small research groups with a platform to incorporate bioinformatics analysis in their research. As a result, the eBioKit has formed an integral part of training and research performed by a wide variety of universities and organizations such as the Pan African Bioinformatics Network (H3ABioNet) as part of the initiative Human Heredity and Health in Africa (H3Africa), the Southern Africa Network for Biosciences (SAnBio) initiative, the Biosciences eastern and central Africa (BecA) hub, and the International Glossina Genome Initiative.

  14. Stand-alone rolling circle amplification combined with capillary electrophoresis for specific detection of small RNA.

    Science.gov (United States)

    Li, Ni; Jablonowski, Carolyn; Jin, Hailing; Zhong, Wenwan

    2009-06-15

    Noncoding small RNAs play diverse, important biological roles through gene expression regulation. However, their low expression levels make it difficult to identify new small RNA species and study their functions, calling for the development of detection schemes with higher simplicity, sensitivity, and specificity. Herein, we reported a straightforward assay that combined the stand-alone rolling circle amplification (RCA) with capillary electrophoresis (CE) for specific and sensitive detection of small RNAs in biological samples. In order to enhance the overall reaction efficiency and simplify the procedure, RCA was not preceded with ligation, and a preformed circular probe was employed as the template for the target small RNA-primed isothermal amplification. The long RCA product was digested and analyzed by CE. Two DNA polymerases, the Phi29 and Bst, were compared for their detection performance. Bst is superior in the aspects of specificity, procedure simplicity, and reproducibility, while Phi29 leads to a 5-fold lower detection limit and is able to detect as low as 35 amol of the target small RNA. Coamplification of an internal standard with the target and employment of the RNase A digestion step allow accurate and reproducible quantification of low amounts of small RNA targets spiked into hundreds of nanograms of the plant total RNA extract with a recovery below 110% using either enzyme. Our assay can be adapted to a capillary array system for high-throughput screening of small RNA expression in biological samples. Also, the one-step isothermal process has the potential to conveniently amplify a very limited amount of the RNA samples, e.g., RNA extracted from only a few cells, inside the capillary column or on a microchip.

  15. Technical and economical assessment of the utilization of photovoltaic systems in residential buildings: The case of Jordan

    International Nuclear Information System (INIS)

    Al-Salaymeh, A.; Al-Hamamre, Z.; Sharaf, F.; Abdelkader, M.R.

    2010-01-01

    This paper studies the feasibility of utilizing photovoltaic systems in a standard residential apartment in Amman city in Jordan. Data on solar radiation, sunshine duration and the ambient temperature has been recorded in Amman city. An apartment in Amman was chosen as a case study to conduct energy and economic calculations. The electrical power needs and cost were calculated for the apartment. The component design and cost of PV system required to supply required energy was calculated and the payback period for the suggested stand-alone PV system in this paper was estimated in a constant inflation rate in electricity price similar to that of interest rate. The calculated payback period was high in a stand-alone system, to decrease payback period a grid-connected PV system is suggested. Considering an annual increase of 3% in electricity price, 15% of payback period was decreased in a stand-alone PV system and 21% in a grid-connected PV system. The output results of this study show that installation of PV system in a residential flat in Jordan may not be economically rewarding owing to the high cost of PV system compared to the cost of grid electricity. A feed-in tariff law of solar electricity may help to reduce PV system cost like the case of Germany. Additional conclusions are PV systems may be economically rewarding in Jordan if applied in locations far from electrical grid or in remote large scale PV power installations to overcome economical limitations of PV technology.

  16. Solar photovoltaic (PV) energy; latest developments in the building integrated and hybrid PV systems

    International Nuclear Information System (INIS)

    Zahedi, A.

    2006-01-01

    Environmental concerns are growing and interest in environmental issues is increasing and the idea of generating electricity with less pollution is becoming more and more attractive. Unlike conventional generation systems, fuel of the solar photovoltaic energy is available at no cost. And solar photovoltaic energy systems generate electricity pollution-free and can easily be installed on the roof of residential as well as on the wall of commercial buildings as grid-connected PV application. In addition to grid-connected rooftop PV systems, solar photovoltaic energy offers a solution for supplying electricity to remote located communities and facilities, those not accessible by electricity companies. The interest in solar photovoltaic energy is growing worldwide. Today, more than 3500MW of photovoltaic systems have been installed all over the world. Since 1970, the PV price has continuously dropped [8]. This price drop has encouraged worldwide application of small-scale residential PV systems. These recent developments have led researchers concerned with the environment to undertake extensive research projects for harnessing renewable energy sources including solar energy. The usage of solar photovoltaic as a source of energy is considered more seriously making future of this technology looks promising. The objective of this contribution is to present the latest developments in the area of solar photovoltaic energy systems. A further objective of this contribution is to discuss the long-term prospect of the solar photovoltaic energy as a sustainable energy supply. [Author

  17. A New Technique for Tracking the Global Maximum Power Point of PV Arrays Operating Under Partial-Shading Conditions

    DEFF Research Database (Denmark)

    Koutroulis, Eftichios; Blaabjerg, Frede

    2012-01-01

    The power-voltage characteristic of photovoltaic (PV) arrays operating under partial-shading conditions exhibits multiple local maximum power points (MPPs). In this paper, a new method to track the global MPP is presented, which is based on controlling a dc/dc converter connected at the PV array...... output, such that it behaves as a constant input-power load. The proposed method has the advantage that it can be applied in either stand-alone or grid-connected PV systems comprising PV arrays with unknown electrical characteristics and does not require knowledge about the PV modules configuration...... within the PV array. The experimental results verify that the proposed global MPP method guarantees convergence to the global MPP under any partial-shading conditions. Compared with past-proposed methods, the global MPP tracking process is accomplished after far fewer PV array power perturbation steps....

  18. Electrification of the Galapagos island, Floreana, using a PV hybrid system and innovative tariff model; Elektrifizierung der Galapagosinsel Floreana mit einem PV Hybridsystem und innovativem Tarifmodell

    Energy Technology Data Exchange (ETDEWEB)

    Vosseler, I.; Vallve, X.; Ramirez, E.; Gavalda, O. [TRAMA TECNOAMBIENTAL, Barcelona (Spain)

    2005-07-01

    The Galapagos islands in Ecuador are Natural Park since 1959. Four of these are inhabited and about 5 million litres of diesel per year are shipped 1000km from the mainland to generate electricity. This could be representative of other parts of the world. Floreana, the smallest inhabited island has 173km2 and about 200 inhabitants; a diesel genset microgrid was operating in the only village of the island (Puerto Velasco Ibarra), 13h per day. The operating scheme for the electric service is representative of a situation where the users pay a standard grid tariff, and the electric utility (EEPG) is sustained through a cross-subsidy of 25.000 US$ per year. Some users in the island are far from the grid and not connected. Small businesses have to operate their own gensets to complement the existing schedule. With funding mainly from the Parque Nacional Galapagos of Ecuador and support to the European NGO SEBA from AECI and the EC, a project for the implementation of Sustainable infrastructures in Floreana has been executed with the objective to reduce substantially the operational deficit, to offer electricity service to ALL potential users 24 hours a day and to reduce substantially the dangerous fuel transports. So, in the late 2003 a MSG (Multi User Hybrid Grid) was commissioned in Puerto Velasco Ibarra which gives electricity service to 54 users by an 18 kWp PV generator backed by the existing diesel gensets. The scattered houses are supplied with individual stand-alone PV systems with a total of 5,9 kWp. This new service approach with PV hybrid technology is supposed to create yearly savings of nearly 20.000 US$ based on a life-cycle analysis compared with the previous generation scheme by genset. The most important aspects of project implementation are that all users are contractually linked to the energy operator in a unified tariff scheme with segmented flat rated monthly fees (whether connected to the MSG or supplied by individual systems), standard grid

  19. Graft subsidence as a predictor of revision surgery following stand-alone lateral lumbar interbody fusion.

    Science.gov (United States)

    Tempel, Zachary J; McDowell, Michael M; Panczykowski, David M; Gandhoke, Gurpreet S; Hamilton, D Kojo; Okonkwo, David O; Kanter, Adam S

    2018-01-01

    OBJECTIVE Lateral lumbar interbody fusion (LLIF) is a less invasive surgical option commonly used for a variety of spinal conditions, including in high-risk patient populations. LLIF is often performed as a stand-alone procedure, and may be complicated by graft subsidence, the clinical ramifications of which remain unclear. The aim of this study was to characterize further the sequelae of graft subsidence following stand-alone LLIF. METHODS A retrospective review of prospectively collected data was conducted on consecutive patients who underwent stand-alone LLIF between July 2008 and June 2015; 297 patients (623 levels) met inclusion criteria. Imaging studies were examined to grade graft subsidence according to Marchi criteria, and compared between those who required revision surgery and those who did not. Additional variables recorded included levels fused, DEXA (dual-energy x-ray absorptiometry) T-score, body mass index, and routine demographic information. The data were analyzed using the Student t-test, chi-square analysis, and logistic regression analysis to identify potential confounding factors. RESULTS Of 297 patients, 34 (11.4%) had radiographic evidence of subsidence and 18 (6.1%) required revision surgery. The median subsidence grade for patients requiring revision surgery was 2.5, compared with 1 for those who did not. Chi-square analysis revealed a significantly higher incidence of revision surgery in patients with high-grade subsidence compared with those with low-grade subsidence. Seven of 18 patients (38.9%) requiring revision surgery suffered a vertebral body fracture. High-grade subsidence was a significant predictor of the need for revision surgery (p subsidence following stand-alone LLIF required revision surgery. When evaluating patients for LLIF, supplemental instrumentation should be considered during the index surgery in patients with a significant risk of graft subsidence.

  20. Influence of Special Weather on Output of PV System

    Science.gov (United States)

    Zhang, Zele

    2018-01-01

    The output of PV system is affected by different environmental factors, therefore, it is important to study the output of PV system under different environmental conditions. Through collecting data on the spot, collecting the output of photovoltaic panels under special weather conditions, and comparing the collected data, the output characteristics of the photovoltaic panels under different weather conditions are obtained. The influence of weather factors such as temperature, humidity and irradiance on the output of photovoltaic panels was investigated.

  1. Economic and policy analysis for solar PV systems in Indiana

    International Nuclear Information System (INIS)

    Jung, Jinho; Tyner, Wallace E.

    2014-01-01

    In recent years, the energy market in the US and globally is expanding the production of renewable energy. Solar energy for electricity is also expanding in the US. Indiana is one of the states expanding solar energy with solar photovoltaic (PV) systems. Therefore, we conduct benefit cost analysis with several uncertain input variables to determine the economics of adopting solar PV systems in Indiana based on policy instruments that could increase adoption of solar PV systems. The specific objectives are analyses of the cost distribution of solar PV systems compared with grid electricity in homes and estimating the probability that solar can be cheaper than electricity from grids under different policy combinations. We first do the analysis under current policy and then the analysis under potential policy options for a variety of scenarios. Also, the results inform government policy makers on how effective the alternative policies for encouraging solar PV systems are. The results show that current policies are important in reducing the cost of solar PV systems. However, with current policies, there is only 50–50 chance of solar being cheaper than electricity from grids. If potential policies are implemented, solar PV systems can be more economical than grid electricity. - Highlights: • We investigate the economics of solar PV systems based on policy instruments. • We do scenario analyses under different combinations of policies. • We examine the probability of solar being cheaper than grid electricity for each scenario. • With current policies, there is 50–50 chance of solar being cheaper than the grid. • With depreciation and carbon tax, solar is much more economical than the grid

  2. Control Strategies for the DAB Based PV Interface System.

    Directory of Open Access Journals (Sweden)

    Hadi M El-Helw

    Full Text Available This paper presents an interface system based on the Dual Active Bridge (DAB converter for Photovoltaic (PV arrays. Two control strategies are proposed for the DAB converter to harvest the maximum power from the PV array. The first strategy is based on a simple PI controller to regulate the terminal PV voltage through the phase shift angle of the DAB converter. The Perturb and Observe (P&O Maximum Power Point Tracking (MPPT technique is utilized to set the reference of the PV terminal voltage. The second strategy presented in this paper employs the Artificial Neural Network (ANN to directly set the phase shift angle of the DAB converter that results in harvesting maximum power. This feed-forward strategy overcomes the stability issues of the feedback strategy. The proposed PV interface systems are modeled and simulated using MATLAB/SIMULINK and the EMTDC/PSCAD software packages. The simulation results reveal accurate and fast response of the proposed systems. The dynamic performance of the proposed feed-forward strategy outdoes that of the feedback strategy in terms of accuracy and response time. Moreover, an experimental prototype is built to test and validate the proposed PV interface system.

  3. Control Strategies for the DAB Based PV Interface System.

    Science.gov (United States)

    El-Helw, Hadi M; Al-Hasheem, Mohamed; Marei, Mostafa I

    2016-01-01

    This paper presents an interface system based on the Dual Active Bridge (DAB) converter for Photovoltaic (PV) arrays. Two control strategies are proposed for the DAB converter to harvest the maximum power from the PV array. The first strategy is based on a simple PI controller to regulate the terminal PV voltage through the phase shift angle of the DAB converter. The Perturb and Observe (P&O) Maximum Power Point Tracking (MPPT) technique is utilized to set the reference of the PV terminal voltage. The second strategy presented in this paper employs the Artificial Neural Network (ANN) to directly set the phase shift angle of the DAB converter that results in harvesting maximum power. This feed-forward strategy overcomes the stability issues of the feedback strategy. The proposed PV interface systems are modeled and simulated using MATLAB/SIMULINK and the EMTDC/PSCAD software packages. The simulation results reveal accurate and fast response of the proposed systems. The dynamic performance of the proposed feed-forward strategy outdoes that of the feedback strategy in terms of accuracy and response time. Moreover, an experimental prototype is built to test and validate the proposed PV interface system.

  4. Developing solar: PV solar system markets in Africa

    International Nuclear Information System (INIS)

    Asali, Karim

    2002-01-01

    Governments, NGO's and UN organisations are increasingly convinced that renewable energies not only help to solve energy problems in Africa but are indispensable in alleviating regional disparities, social problems and bridging the digital gap. Still, many years after introducing high efficiency solar PV systems the necessary breakthrough of implementing them on a mass scale is still not a reality. The author provides perspectives on developing solar PV in Africa. (Author)

  5. A comparative sizing analysis of a renewable energy supplied stand-alone house considering both demand side and source side dynamics

    International Nuclear Information System (INIS)

    Elma, Onur; Selamogullari, Ugur Savas

    2012-01-01

    Highlights: ► Backup sizing analyses for PV–Wind energy supplied stand-alone house are completed. ► Source and demand side dynamics are considered for the first time in backup sizing. ► Backup size is reduced by 10% compared to backup size found with hourly values. ► The importance of data resolution on sizing study in such systems is shown. -- Abstract: Solar and wind energy use to supply the electrical demand of a stand-alone residential house is investigated. Combining solar and wind energy sources provide more reliable power source for stand-alone applications since they complement each other. Backup units (battery/supercapacitor) are also needed for uninterrupted energy. For a proper backup sizing in such systems, high resolution load data, wind speed and solar radiation data must be used as compared to the use of hourly averaged data found in literature. In this study, high resolution data on both load side and source side are collected experimentally. Then, collected data used as input to system simulations in Matlab/Simulink for sizing the backup in the considered hybrid power system. Backup state of the charge (SOC) is used as decision criteria. It is shown that, when load and source dynamics are considered, approximately 10% less backup size is required compared to backup size found with hourly averaged values. The study shows the importance of data resolution on backup sizing in such systems and could be a guide for renewable energy system designers.

  6. Prospect of solar-PV/biogas/diesel generator hybrid energy system of an off-grid area in Bangladesh

    Science.gov (United States)

    Mandal, Soumya; Yasmin, Hosna; Sarker, M. R. I.; Beg, M. R. A.

    2017-12-01

    The study presents an analysis and suggests about how renewable sources of energy can be an alternative option to produce electricity in an off-grid area. A case study is done by surveying 235 households in an off-grid area. Techno-economic analysis of the hybrid energy system is employed by using Hybrid Optimization of Multiple Energy Resources (HOMER) software. Four solar-PV modules (each of 1kW), two biogas generators (each of 3kW), three diesel generators (each of 5kW), five batteries (each of 160 Ah) and 5kW converter is found to be the best configuration in terms of Cost of Energy (COE), environmental conditions and Renewable Fraction (RF). The Cost of Energy (COE), Net Present Cost (NPC), capital cost of this configuration is found BDT15.382, BDT10007224, and BDT2582433 respectively. The renewable fraction of this system is found 75% which indicates a lower emission compared with thegrid based system and stand-alone diesel system. Although the COE is higher than grid electricity, this system offers a cheaper option than using kerosene oil and solar home systems (SHSs).

  7. Plug and Play PV Systems for American Homes

    Energy Technology Data Exchange (ETDEWEB)

    Hoepfner, Christian [Fraunhofer USA, Inc., Boston, MA (United States)

    2016-12-22

    The core objectives of the Plug & Play PV Systems Project were to develop a PV system that can be installed on a residential rooftop for less than $1.50/W in 2020, and in less than 10 hours (from point of purchase to commissioning). The Fraunhofer CSE team’s approach to this challenge involved a holistic approach to system design – hardware and software – that make Plug & Play PV systems: • Quick, easy, and safe to install • Easy to demonstrate as code compliant • Permitted, inspected, and interconnected via an electronic process Throughout the three years of work during this Department of Energy SunShot funded project, the team engaged in a substantive way with inspectional services departments and utilities, manufacturers, installers, and distributors. We received iterative feedback on the system design and on ideas for how such systems can be commercialized. This ultimately led us to conceiving of Plug & Play PV Systems as a framework, with a variety of components compatible with the Plug & Play PV approach, including string or microinverters, conventional modules or emerging lightweight modules. The framework enables a broad group of manufacturers to participate in taking Plug & Play PV Systems to market, and increases the market size for such systems. Key aspects of the development effort centered on the system hardware and associated engineering work, the development of a Plug & Play PV Server to enable the electronic permitting, inspection and interconnection process, understanding the details of code compliance and, on occasion, supporting applications for modifications to the code to allow lightweight modules, for example. We have published a number of papers on our testing and assessment of novel technologies (e.g., adhered lightweight modules) and on the electronic architecture.

  8. Online retrieval of patient information by asynchronous communication between general purpose computer and stand-alone personal computer

    International Nuclear Information System (INIS)

    Tsutsumi, Reiko; Takahashi, Kazuei; Sato, Toshiko; Komatani, Akio; Yamaguchi, Koichi

    1988-01-01

    Asynchronous communication was made between host (FACOM M-340) and personal computer (OLIBETTIE S-2250) to get patient's information required for RIA test registration. The retrieval system consists of a keyboad input of six numeric codes, patient's ID, and a real time reply containing six parameters for the patient. Their identified parameters are patient's name, sex, date of birth (include area), department, and out- or inpatient. Linking this program to RIA registration program for individual patient, then, operator can input name of RIA test requested. Our simple retrieval program made a useful data network between different types of host and stand-alone personal computers, and enabled us accurate and labor-saving registration for RIA test. (author)

  9. Computer aided design of systems for solar powered water pumping by photovoltaics

    OpenAIRE

    2012-01-01

    D.Ing. Low system efficiency is a critical problem in photovoltaic (PV) applications due to low efficiency of solar cells. Despite this shortcoming, stand-alone PV systems, have proven to be economical and reliable choices in some applications such as telecommunications, vaccine refrigeration and water pumping in remote locations. In this study, CAD algorithms for the design of PV water pumping systems have been developed with the objective of maximizing the conversion efficiency from the ...

  10. Fuzzy Logic Based MPPT Controller for a PV System

    Directory of Open Access Journals (Sweden)

    Carlos Robles Algarín

    2017-12-01

    Full Text Available The output power of a photovoltaic (PV module depends on the solar irradiance and the operating temperature; therefore, it is necessary to implement maximum power point tracking controllers (MPPT to obtain the maximum power of a PV system regardless of variations in climatic conditions. The traditional solution for MPPT controllers is the perturbation and observation (P&O algorithm, which presents oscillation problems around the operating point; the reason why improving the results obtained with this algorithm has become an important goal to reach for researchers. This paper presents the design and modeling of a fuzzy controller for tracking the maximum power point of a PV System. Matlab/Simulink (MathWorks, Natick, MA, USA was used for the modeling of the components of a 65 W PV system: PV module, buck converter and fuzzy controller; highlighting as main novelty the use of a mathematical model for the PV module, which, unlike diode based models, only needs to calculate the curve fitting parameter. A P&O controller to compare the results obtained with the fuzzy control was designed. The simulation results demonstrated the superiority of the fuzzy controller in terms of settling time, power loss and oscillations at the operating point.

  11. Subsidence after single-level anterior cervical fusion with a stand-alone cage.

    Science.gov (United States)

    Park, Jae-Young; Choi, Ki-Young; Moon, Bong Ju; Hur, Hyuk; Jang, Jae-Won; Lee, Jung-Kil

    2016-11-01

    To investigate the risk factors for subsidence in patients treated with stand-alone anterior cervical discectomy and fusion (ACDF) using polyetheretherketone (PEEK) cages for single-level degenerative cervical disease. Seventy-seven consecutive patients who underwent single-level stand-alone ACDF with a PEEK cage between 2005 and 2012 were included. Subsidence was defined as a decrease in the interbody height of more than 3mm on radiographs at the 1-year follow-up compared with that in the immediate post-operative image. Patients were divided into the subsidence and non-subsidence groups. The following factors were investigated in relation to the occurrence of subsidence: age, pre-operative overall cervical sagittal angle, segmental angle of the operated level, interbody height, cage height, cage devices and cage location (distance between anterior margin of the body endplate and that of the cage). The clinical outcomes were assessed with visual analog scale, modified Japanese Orthopedic Association score and neck disability index. Twenty-six out of the 77 (33.8%) patients had radiological signs of cage subsidence. Solid fusion was achieved in 25 out of the 26 patients (96.2%) in the subsidence group and in 47 out of the 51 patients (92.2%) in the non-subsidence group. More than 3mm distance between anterior margin of the vertebral body and that of the cage was significantly associated with subsidence (psubsidence did not correlate with fusion rate or clinical outcomes. Cage location was the only significant risk factor. Therefore, cage location should be taken into consideration during stand-alone ACDF using PEEK cages. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Residential Solar PV Systems in the Carolinas: Opportunities and Outcomes.

    Science.gov (United States)

    Alqahtani, Bandar Jubran; Holt, Kyra Moore; Patiño-Echeverri, Dalia; Pratson, Lincoln

    2016-02-16

    This paper presents a first-order analysis of the feasibility and technical, environmental, and economic effects of large levels of solar photovoltaic (PV) penetration within the services areas of the Duke Energy Carolinas (DEC) and Duke Energy Progress (DEP). A PV production model based on household density and a gridded hourly global horizontal irradiance data set simulates hourly PV power output from roof-top installations, while a unit commitment and real-time economic dispatch (UC-ED) model simulates hourly system operations. We find that the large generating capacity of base-load nuclear power plants (NPPs) without ramping capability in the region limits PV integration levels to 5.3% (6510 MW) of 2015 generation. Enabling ramping capability for NPPs would raise the limit of PV penetration to near 9% of electricity generated. If the planned retirement of coal-fired power plants together with new installations and upgrades of natural gas and nuclear plants materialize in 2025, and if NPPs operate flexibly, then the share of coal-fired electricity will be reduced from 37% to 22%. A 9% penetration of electricity from PV would further reduce the share of coal-fired electricity by 4-6% resulting in a system-wide CO2 emissions rate of 0.33 to 0.40 tons/MWh and associated abatement costs of 225-415 (2015$ per ton).

  13. Stand-alone and Interdisciplinary Course Design for Engineering Education for Sustainable Development

    DEFF Research Database (Denmark)

    Arsat, M.; Holgaard, Jette Egelund; de Graaff, Erik

    In order to embed ESD in the EE curriculum, several approaches has been introduced and practiced in higher education institutions. One of the approaches is to introduce a new ESD course as an add-on to the existing curriculum being either compulsory or elective and either designed for a single...... and reported examples of other ESD courses of the same kind. The presented conceptual framework is put to practice, characterising the AAU course as a stand-alone interdisciplinary course with a consensual approach. The conclusion is that the conceptual framework can provide an awareness of the design features...

  14. Incidence and impact of implant subsidence after stand-alone lateral lumbar interbody fusion.

    Science.gov (United States)

    Bocahut, N; Audureau, E; Poignard, A; Delambre, J; Queinnec, S; Flouzat Lachaniette, C-H; Allain, J

    2017-12-30

    Few data are available on the occurrence after stand-alone lateral lumbar interbody fusion (LLIF) of implant subsidence, whose definition and incidence vary across studies. The primary objective of this work was to determine the incidence of subsidence 1 year postoperatively, using an original measurement method, whose validity was first assessed. The secondary objective was to assess the clinical impact of subsidence. Implant subsidence after stand-alone LLIF is a common complication that can adversely affect clinical outcomes. Of 69 included patients who underwent stand-alone LLIF, 67 (97%) were re-evaluated at least 1 year later. Furthermore, 63 (91%) patients had two available computed tomography (CT) scans for assessing subsidence, one performed immediately after surgery and the other 1 year later. Reproducibility of the original measurement method was assessed in a preliminary study. Subsidence was defined as at least 4mm loss of fused space height. The incidence of subsidence was 32% (20 patients). Subsidence was global in 7 (11%) patients and partial in 13 (21%) patients. Mean loss of height was 5.5±1.5mm. Subsidence predominated anteriorly in 50% of cases. The lordotic curvature of the fused segment was altered in 50% of patients, by a mean of 8°±3°. Fusion was achieved in 67/69 (97%) patients. The Oswestry score and visual analogue scale scores for low-back and nerve-root pain were significantly improved after 1 year in the overall population and in the groups with and without subsidence. Reproducibility of our measurement method was found to be excellent. Subsidence was common but without significant clinical effects after 1 year. Nevertheless, subsidence can be associated with pain and can result in loss of lumbar lordosis, which is a potential risk factor for degenerative disease of the adjacent segments. A score for predicting the risk of subsidence will now be developed by our group as a tool for improving patient selection to stand-alone LLIF

  15. Solar Photovoltaic (PV) Distributed Generation Systems - Control and Protection

    Science.gov (United States)

    Yi, Zhehan

    This dissertation proposes a comprehensive control, power management, and fault detection strategy for solar photovoltaic (PV) distribution generations. Battery storages are typically employed in PV systems to mitigate the power fluctuation caused by unstable solar irradiance. With AC and DC loads, a PV-battery system can be treated as a hybrid microgrid which contains both DC and AC power resources and buses. In this thesis, a control power and management system (CAPMS) for PV-battery hybrid microgrid is proposed, which provides 1) the DC and AC bus voltage and AC frequency regulating scheme and controllers designed to track set points; 2) a power flow management strategy in the hybrid microgrid to achieve system generation and demand balance in both grid-connected and islanded modes; 3) smooth transition control during grid reconnection by frequency and phase synchronization control between the main grid and microgrid. Due to the increasing demands for PV power, scales of PV systems are getting larger and fault detection in PV arrays becomes challenging. High-impedance faults, low-mismatch faults, and faults occurred in low irradiance conditions tend to be hidden due to low fault currents, particularly, when a PV maximum power point tracking (MPPT) algorithm is in-service. If remain undetected, these faults can considerably lower the output energy of solar systems, damage the panels, and potentially cause fire hazards. In this dissertation, fault detection challenges in PV arrays are analyzed in depth, considering the crossing relations among the characteristics of PV, interactions with MPPT algorithms, and the nature of solar irradiance. Two fault detection schemes are then designed as attempts to address these technical issues, which detect faults inside PV arrays accurately even under challenging circumstances, e.g., faults in low irradiance conditions or high-impedance faults. Taking advantage of multi-resolution signal decomposition (MSD), a powerful signal

  16. Industrial application of PV/T solar energy systems

    International Nuclear Information System (INIS)

    Kalogirou, S.A.; Tripanagnostopoulos, Y.

    2007-01-01

    Hybrid photovoltaic/thermal (PV/T) systems consist of PV modules and heat extraction units mounted together. These systems can simultaneously provide electrical and thermal energy, thus achieving a higher energy conversion rate of the absorbed solar radiation than plain photovoltaics. Industries show high demand of energy for both heat and electricity and the hybrid PV/T systems could be used in order to meet this requirement. In this paper the application aspects in the industry of PV/T systems with water heat extraction is presented. The systems are analyzed with TRNSYS program for three locations Nicosia, Athens and Madison that are located at different latitudes. The system comprises 300 m 2 of hybrid PV/T collectors producing both electricity and thermal energy and a 10 m 3 water storage tank. The work includes the study of an industrial process heat system operated at two load supply temperatures of 60 deg. C and 80 deg. C. The results show that the electrical production of the system, employing polycrystalline solar cells, is more than the amorphous ones but the solar thermal contribution is slightly lower. A non-hybrid PV system produces about 25% more electrical energy but the present system covers also, depending on the location, a large percentage of the thermal energy requirement of the industry considered. The economic viability of the systems is proven, as positive life cycle savings are obtained in the case of hybrid systems and the savings are increased for higher load temperature applications. Additionally, although amorphous silicon panels are much less efficient than the polycrystalline ones, better economic figures are obtained due to their lower initial cost, i.e., they have better cost/benefit ratio

  17. Techno-economic feasibility of hybrid diesel/PV/wind/battery electricity generation systems for non-residential large electricity consumers under southern Iran climate conditions

    International Nuclear Information System (INIS)

    Baneshi, Mehdi; Hadianfard, Farhad

    2016-01-01

    Highlights: • A hybrid electricity generation system for a large electricity consumer was studied. • The PV and wind electricity potentials under given climate conditions were evaluated. • Technical, economical, and environmental issues of different systems were discussed. • The optimum configuration of components was obtained. • The impacts of governmental incentives on economic viability of systems were examined. - Abstract: This paper aims to study the techno-economical parameters of a hybrid diesel/PV/wind/battery power generation system for a non-residential large electricity consumer in the south of Iran. As a case study, the feasibility of running a hybrid system to meet a non-residential community’s load demand of 9911 kWh daily average and 725 kW peak load demand was investigated. HOMER Pro software was used to model the operation of the system and to identify the appropriate configuration of it based on comparative technical, economical, and environmental analysis. Both stand alone and grid connected systems were modeled. The impacts of annual load growth and governmental energy policies such as providing low interest loan to renewable energy projects, carbon tax, and modifying the grid electricity price on viability of the system were discussed. Results show that for off-grid systems the cost of electricity (COE) and the renewable fraction of 9.3–12.6 ₵/kWh and 0–43.9%, respectively, are achieved with photovoltaic (PV) panel, wind turbine, and battery sizes of 0–1000 kW, 0–600 kW, and 1300 kWh, respectively. For on grid systems without battery storage the range of COE and renewable fraction are 5.7–8.4 ₵/kWh and 0–53%, respectively, for the same sizes of PV panel and wind turbine.

  18. Stand-alone anterior lumbar interbody fusion for treatment of degenerative spondylolisthesis.

    Science.gov (United States)

    Rao, Prashanth J; Ghent, Finn; Phan, Kevin; Lee, Keegan; Reddy, Rajesh; Mobbs, Ralph J

    2015-10-01

    We sought to evaluate the clinical and radiologic efficacy of stand-alone anterior lumbar interbody fusion (ALIF) for low grade degenerative spondylolisthesis, the favoured surgical management approach at our institution. The optimal approach for surgical management of spondylolisthesis remains contentious. We performed a prospective analysis of all consecutive patients with low grade lumbar spondylolisthesis who underwent ALIF between 2009 and 2013 by a single surgeon (n=27). The mean age was 64.9 years with a male to female ratio of 14:13. There were 32 levels operated and the average preoperative spondylolisthesis was 14.8%, which reduced to 6.4% postoperatively and 9.4% at the latest follow-up (p=0001). Postoperative disc height was increased to 175% of preoperative values and was statistically significant (pspondylolisthesis reduction (p=0.04) and the only clinical factor affecting reduction was body mass index (p=0.04). The present study provides encouraging short term results for stand-alone ALIF as a procedure for low grade lumbar degenerative spondylolisthesis. Future studies should include adequately powered, prospective, multicentre registry studies with long term follow-up to allow a better assessment of the relative benefits and risks. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Fracture of the L-4 vertebral body after use of a stand-alone interbody fusion device in degenerative spondylolisthesis for anterior L3-4 fixation.

    Science.gov (United States)

    Kwon, Yoon-Kwang; Jang, Ju-Hee; Lee, Choon-Dae; Lee, Sang-Ho

    2014-06-01

    Many studies attest to the excellent results achieved using anterior lumbar interbody fusion (ALIF) for degenerative spondylolisthesis. The purpose of this report is to document a rare instance of L-4 vertebral body fracture following use of a stand-alone interbody fusion device for L3-4 ALIF. The patient, a 55-year-old man, had suffered intractable pain of the back, right buttock, and left leg for several weeks. Initial radiographs showed Grade I degenerative spondylolisthesis, with instability in the sagittal plane (upon 15° rotation) and stenosis of central and both lateral recesses at the L3-4 level. Anterior lumbar interbody fusion of the affected vertebrae was subsequently conducted using a stand-alone cage/plate system. Postoperatively, the severity of spondylolisthesis diminished, with resolution of symptoms. However, the patient returned 2 months later with both leg weakness and back pain. Plain radiographs and CT indicated device failure due to anterior fracture of the L-4 vertebral body, and the spondylolisthesis had recurred. At this point, bilateral facetectomies were performed, with reduction/fixation of L3-4 by pedicle screws. Again, degenerative spondylolisthesis improved postsurgically and symptoms eased, with eventual healing of the vertebral body fracture. This report documents a rare instance of L-4 vertebral body fracture following use of a stand-alone device for ALIF at L3-4, likely as a consequence of angular instability in degenerative spondylolisthesis. Under such conditions, additional pedicle screw fixation is advised.

  20. PV Reconfiguration Systems: a Technical and Economic Study

    Directory of Open Access Journals (Sweden)

    Caruso M.

    2017-03-01

    Full Text Available Dynamical electrical array reconfiguration strategies for grid-connected PV systems have been proposed as solution to improve energy production due to the mismatch effect of PV plants during partial shading conditions. Strategies are based on the use of dynamic connections between PV panels given by the employment of switches that allow for each panel the series, parallel or exclusion connections, physically changing the electrical connections between the related PV modules, consequentially modifying the layout of the plant. Usually the cost of the dynamic matrix is not taken into account. This novel work evaluates the economic advantages obtained by the use of reconfiguration strategies in PV systems, by taking into consideration the price of energy due to incentives in different European and non-European countries and correlates it with the employment of two types of reconfigurators, with different internal structures. For each of the incentives proposed by the different Countries, the main strength and weakness points of the possible investment are highlighted and critically analyzed. From this analysis, it can be stated that the adoption of reconfiguration systems, in certain cases, can be a very convenient solution.

  1. Sustainable recycling technologies for Solar PV off-grid system

    Directory of Open Access Journals (Sweden)

    Uppal Bhavesh

    2017-01-01

    Full Text Available Policy makers throughout the world have accepted climate change as a repercussion of fossil fuel exploitation. This has led the governments to integrate renewable energy streams in their national energy mix. PV off-grid Systems have been at the forefront of this transition because of their permanently increasing efficiency and cost effectiveness. These systems are expected to produce large amount of different waste streams at the end of their lifetime. It is important that these waste streams should be recycled because of the lack of available resources. Our study found that separate researches have been carried out to increase the efficiencies of recycling of individual PV system components but there is a lack of a comprehensive methodical research which details efficient and sustainable recycling processes for the entire PV off-grid system. This paper reviews the current and future recycling technologies for PV off-grid systems and presents a scheme of the most sustainable recycling technologies which have the potential for adoption. Full Recovery End-of-Life Photovoltaic (FRELP recycling technology can offer opportunities to sustainably recycle crystalline silicon PV modules. Electro-hydrometallurgical process & Vacuum technologies can be used for recovering lead from lead acid batteries with a high recovery rate. The metals in the WEEE can be recycled by using a combination of biometallurgical technology, vacuum metallurgical technology and other advanced metallurgical technologies (utrasonical, mechano-chemical technology while the plastic components can be effectively recycled without separation by using compatibilizers. All these advanced technologies when used in combination with each other provide sustainable recycling options for growing PV off-grid systems waste. These promising technologies still need further improvement and require proper integration techniques before implementation.

  2. Sustainable recycling technologies for Solar PV off-grid system

    Science.gov (United States)

    Uppal, Bhavesh; Tamboli, Adish; Wubhayavedantapuram, Nandan

    2017-11-01

    Policy makers throughout the world have accepted climate change as a repercussion of fossil fuel exploitation. This has led the governments to integrate renewable energy streams in their national energy mix. PV off-grid Systems have been at the forefront of this transition because of their permanently increasing efficiency and cost effectiveness. These systems are expected to produce large amount of different waste streams at the end of their lifetime. It is important that these waste streams should be recycled because of the lack of available resources. Our study found that separate researches have been carried out to increase the efficiencies of recycling of individual PV system components but there is a lack of a comprehensive methodical research which details efficient and sustainable recycling processes for the entire PV off-grid system. This paper reviews the current and future recycling technologies for PV off-grid systems and presents a scheme of the most sustainable recycling technologies which have the potential for adoption. Full Recovery End-of-Life Photovoltaic (FRELP) recycling technology can offer opportunities to sustainably recycle crystalline silicon PV modules. Electro-hydrometallurgical process & Vacuum technologies can be used for recovering lead from lead acid batteries with a high recovery rate. The metals in the WEEE can be recycled by using a combination of biometallurgical technology, vacuum metallurgical technology and other advanced metallurgical technologies (utrasonical, mechano-chemical technology) while the plastic components can be effectively recycled without separation by using compatibilizers. All these advanced technologies when used in combination with each other provide sustainable recycling options for growing PV off-grid systems waste. These promising technologies still need further improvement and require proper integration techniques before implementation.

  3. Subsidence and nonunion after anterior cervical interbody fusion using a stand-alone polyetheretherketone (PEEK) cage.

    Science.gov (United States)

    Yang, Jae Jun; Yu, Chang Hun; Chang, Bong-Soon; Yeom, Jin Sup; Lee, Jae Hyup; Lee, Choon-Ki

    2011-03-01

    The purposes of the present study are to evaluate the subsidence and nonunion that occurred after anterior cervical discectomy and fusion using a stand-alone intervertebral cage and to analyze the risk factors for the complications. Thirty-eight patients (47 segments) who underwent anterior cervical fusion using a stand-alone polyetheretherketone (PEEK) cage and an autologous cancellous iliac bone graft from June 2003 to August 2008 were enrolled in this study. The anterior and posterior segmental heights and the distance from the anterior edge of the upper vertebra to the anterior margin of the cage were measured on the plain radiographs. Subsidence was defined as ≥ a 2 mm (minor) or 3 mm (major) decrease of the segmental height at the final follow-up compared to that measured at the immediate postoperative period. Nonunion was evaluated according to the instability being ≥ 2 mm in the interspinous distance on the flexion-extension lateral radiographs. The anterior and posterior segmental heights decreased from the immediate postoperative period to the final follow-up at 1.33 ± 1.46 mm and 0.81 ± 1.27 mm, respectively. Subsidence ≥ 2 mm and 3 mm were observed in 12 segments (25.5%) and 7 segments (14.9%), respectively. Among the expected risk factors for subsidence, a smaller anteroposterior (AP) diameter (14 mm vs. 12 mm) of cages (p = 0.034; odds ratio [OR], 0.017) and larger intraoperative distraction (p = 0.041; OR, 3.988) had a significantly higher risk of subsidence. Intervertebral nonunion was observed in 7 segments (7/47, 14.9%). Compared with the union group, the nonunion group had a significantly higher ratio of two-level fusion to one-level fusions (p = 0.001). Anterior cervical fusion using a stand-alone cage with a large AP diameter while preventing anterior intraoperative over-distraction will be helpful to prevent the subsidence of cages. Two-level cervical fusion might require more careful attention for avoiding nonunion.

  4. Stand-alone differential capacitance force sensors with sub-nano-newton sensitivity

    Science.gov (United States)

    Ye, Jilong; Sun, Taotao; Huang, Dong; Li, Zhihong; Lin, Li

    2017-09-01

    This paper presents structure design, microfabrication processes, calibration techniques and experimental results of differential capacitance force sensors with features of sub-nano-newton sensitivity, up to 10 000 Hz sampling rate, and applicability as stand-alone devices. The representative sensor demonstrates a force resolution of 0.11 nN at a 19 Hz sampling rate or 1.47 nN at 10 000 Hz. A novel asymmetric differential capacitance structure proposed results in remarkable increase in the ratio of measurement range to resolution in comparison with traditional symmetric structure. In addition, the stiction between silicon and glass caused by the capillary force during dicing is eliminated by the use of hydrophobization treatment. Such a treatment is essential to successfully fabricate structures with a large ratio of overlapped area to gap in silicon/glass anodic bonding processes.

  5. Study of Stand-Alone Microgrid under Condition of Faults on Distribution Line

    Science.gov (United States)

    Malla, S. G.; Bhende, C. N.

    2014-10-01

    The behavior of stand-alone microgrid is analyzed under the condition of faults on distribution feeders. During fault since battery is not able to maintain dc-link voltage within limit, the resistive dump load control is presented to do so. An inverter control is proposed to maintain balanced voltages at PCC under the unbalanced load condition and to reduce voltage unbalance factor (VUF) at load points. The proposed inverter control also has facility to protect itself from high fault current. Existing maximum power point tracker (MPPT) algorithm is modified to limit the speed of generator during fault. Extensive simulation results using MATLAB/SIMULINK established that the performance of the controllers is quite satisfactory under different fault conditions as well as unbalanced load conditions.

  6. Imagery rescripting as a stand-alone treatment for patients with social phobia: a case series.

    Science.gov (United States)

    Frets, Petra G; Kevenaar, Ciska; van der Heiden, Colin

    2014-03-01

    The majority of patients with social phobia reports experiencing negative images, usually linked to memories of earlier aversive social experiences. Several studies have indicated that such negative self-imagery appears to have a causal role in maintaining social phobia, which suggests that interventions aimed at dealing with these images could be beneficial in the treatment of social phobia. One potentially powerful approach is imagery rescripting (IR), a clinical intervention that focuses on changing the meaning and impact of unpleasant memories. In the treatment of social phobia IR was only used as part of a broader cognitive-behavioral treatment package. However, we propose that IR alone might also be an effective treatment for this anxiety disorder. The present study reports an initial evaluation of the application of IR as a stand-alone treatment for six adult outpatients presenting with social phobia. A single case series using an A-B replication across patients design was employed. Following a no-treatment baseline period, IR was delivered weekly and patients were followed up for 3 and 6 months. For all patients, substantial reductions were obtained on all outcome measures at post-treatment, and gains were largely maintained at 6-months follow-up. The generalizability of the effects of IR for social phobia is limited by the small number of patients treated by only one therapist. The results of this preliminary case series suggest that IR as a stand alone treatment is an apparently effective intervention in the treatment of patients with social phobia, and indicate that controlled evaluation of its efficacy might be worthwhile. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. A Meta-Analytic Review of Stand-Alone Interventions to Improve Body Image.

    Directory of Open Access Journals (Sweden)

    Jessica M Alleva

    Full Text Available Numerous stand-alone interventions to improve body image have been developed. The present review used meta-analysis to estimate the effectiveness of such interventions, and to identify the specific change techniques that lead to improvement in body image.The inclusion criteria were that (a the intervention was stand-alone (i.e., solely focused on improving body image, (b a control group was used, (c participants were randomly assigned to conditions, and (d at least one pretest and one posttest measure of body image was taken. Effect sizes were meta-analysed and moderator analyses were conducted. A taxonomy of 48 change techniques used in interventions targeted at body image was developed; all interventions were coded using this taxonomy.The literature search identified 62 tests of interventions (N = 3,846. Interventions produced a small-to-medium improvement in body image (d+ = 0.38, a small-to-medium reduction in beauty ideal internalisation (d+ = -0.37, and a large reduction in social comparison tendencies (d+ = -0.72. However, the effect size for body image was inflated by bias both within and across studies, and was reliable but of small magnitude once corrections for bias were applied. Effect sizes for the other outcomes were no longer reliable once corrections for bias were applied. Several features of the sample, intervention, and methodology moderated intervention effects. Twelve change techniques were associated with improvements in body image, and three techniques were contra-indicated.The findings show that interventions engender only small improvements in body image, and underline the need for large-scale, high-quality trials in this area. The review identifies effective techniques that could be deployed in future interventions.

  8. High Efficient Bidirectional Battery Converter for residential PV Systems

    DEFF Research Database (Denmark)

    Pham, Cam; Kerekes, Tamas; Teodorescu, Remus

    2012-01-01

    the power to balance it. High efficient bidirectional converter for the battery storage is required due high system cost and because the power is processed twice. A 1.5kW prototype is designed and built with CoolMOS and SiC diodes, >;95% efficiency has been obtained with 200 kHz hard switching.......Photovoltaic (PV) installation is suited for the residential environment and the generation pattern follows the distribution of residential power consumption in daylight hours. In the cases of unbalance between generation and demand, the Smart PV with its battery storage can absorb or inject...

  9. Environmental impacts of PV systems -- Ground-based vs BIPV

    International Nuclear Information System (INIS)

    Baumann, A.E.; Hill, R.; Hynes, K.M.

    1997-01-01

    This study is part of the ExternE program of the European Commission on the external costs of the photovoltaic (PV) fuel cycle. The objective of this paper is the quantitative evaluation of the main environmental impacts of two selected PV systems--the ground-based 1MWp system in Toledo, Spain and the 40 kWp building integrated facade in Newcastle upon Tyne, NE England, using the methodology of life cycle analysis (LCA). Both systems use silicon wafer technology at present, but the Newcastle facade was also studied with the incorporation CdTe modules. The results of the LCA show that atmospheric emissions are the priority impacts with respect to the assessed PV systems. Comparing Si wafer systems, the CO 2 emissions were 88 t/GWh for the Toledo PV plant and 143t/GWh for the BIPV facade. If the facade had used electrodeposited CdTe, the CO 2 emissions would fall to about 50t/GWh

  10. Prospects for PV: a learning curve analysis

    International Nuclear Information System (INIS)

    Zwaan, Bob van der; Rabi, A.

    2003-01-01

    This article gives an overview of the current state-of-the-art of photovoltaic electricity technology, and addresses its potential for cost reductions over the first few decades of the 21st century. Current PV production cost ranges are presented, both in terms of capacity installation and electricity generation, of single crystalline silicon, multi-crystalline silicon, amorphous silicon and other thin film technologies. Possible decreases of these costs are assessed, as expected according to the learning-curve methodology. We also estimate how much PV could gain if external costs (due to environmental and health damage) of energy were internalised, for example by an energy tax. Our conclusions are that, (1) mainly due its high costs, PV electricity is unlikely to play a major role in global energy supply and carbon emissions abatement before 2020, (2) extrapolating learning curves observed in the past, one can expect its costs to decrease significantly over the coming years, so that a considerable PV electricity share world-wide could materialise after 2020, (3) niche-market applications, e.g. using stand-alone systems in remote areas, are crucial for continuing 'the ride along the learning curve', (4) damage costs of conventional (fossil) power sources are considerable, and their internalisation would improve the competitiveness of PV, although probably not enough to close the current cost gap. (author)

  11. Development of solar energy for efficient PV application systems

    International Nuclear Information System (INIS)

    Said, Aziz

    2006-01-01

    It is essential to increase research, development, awareness for the application of solar energy as an important source of life. The cost of PV systems has decreased due to the improvement in techniques of manufacturing and performance. In reality, photovoltaic is one technology that allows the production of electricity with only two components: technological, which is the PV module and environmental, which is the sun. The knowledge of the components market represents a critical parameters in establishing sustainable industrial applications on different activity sectors. This paper illustrates the advantages of using photovoltaic in rural area and their economic and environmental impact. In regions where petroleum or other fossil fuels are not available, and where these remote area are not connected to the electrical grid, there is a strong and increasing demand for the technologies related to photovoltaic application systems. Water extracting and pumping, telecommunication and lighting, irrigation systems, electrical driven cars and trucks represent some of these important applications. The paper also develops critical skills for the most useful PV application in Egypt and provide to the industry a development forecast for the new technology. Then an initiation contacts and cooperation on PV application between industries specially in North Africa Middle East in order to improve the reliability and to get cheaper systems.(Author)

  12. PVSOFT99 -PHOTOVOL TAlC (PV) SYSTEM SIZING AND ...

    African Journals Online (AJOL)

    storage). Accurate system sizing is therefore very important for proper ·utilization of the PV technology. The sizing problem is compounded by the fact that the energy source,' the solar radiation, is a variable source wliose properties can not be precisely controlled. Thus a good sizing procedure is always accompanied by.

  13. Experimental comparison of two PV direct-coupled solar water heating systems with the traditional system

    International Nuclear Information System (INIS)

    Ji, Jie; Wang, Yanqiu; Yuan, Weiqi; Sun, Wei; He, Wei; Guo, Chao

    2014-01-01

    Highlights: • A design approach of PV-coupled solar water heating system (SWHS) is presented. • Two different designs of PV modules are proposed and investigated. • A comparative test rig of PV-coupled SWHS and traditional SWHS is set up. • A flow rate increasing with solar irradiation is recommended. - Abstract: Simple and reliable, PV direct-coupled DC pumps are promising in solar water heating systems (SWHS). However, there is limited experimental data on the performance comparison of PV-coupled SWHS with traditional SWHS. Hence in this study, a comparative test rig is set up to measure and analyze the performance of the PV-coupled SWHS and the traditional system under the same conditions. The experimental results show that on sunny days the PV-coupled SWHS has similar daily thermal efficiency as the traditional SWHS, and slightly higher efficiency after improving the design of the PV module. Under low irradiation, the PV-coupled SWHS gains much more heat than the traditional SWHS, which indicates the potential of the PV-coupled SWHS having much higher efficiency than the traditional SWHS on cloudy days. In order to improve the performance of the PV-coupled SWHS, two different designs of PV module are proposed, and their influence on the pump startup characteristics, the flow rate profile, and the thermal efficiency of the system is investigated. It is found that the modified design of the PV module can reduce the requirement of PV cells and increase the efficiency of the system

  14. Perancangan Photovoltaic Stand Alone Sebagai Catu Daya Pada Base Transceiver Station Telekomunikasi Di Pulau Nusa Penida

    Directory of Open Access Journals (Sweden)

    I P Eka Indrawan

    2013-06-01

    Full Text Available Salah satu perangkat dalam jaringan komunikasi seluler adalah BTS (Base Transceiver Station. BTS yang ada di pulau Nusa Penida adalah BTS Nusa Penida dengan alamat desa kutampi dengan luas 500 m2. Sistem kelistrikan BTS  Nusa Penida dipasok oleh PLN dan genset,  dimana pada saat terjadi pemadaman energi listrik pada umumnya mempergunakan genset sebagai sumber energi listrik. Penggunaan genset mengakibatkan biaya operasional sangat tinggi, untuk itu diperlukan sumber lain yang lebih efisien. Besarnya potensi insolasi sinar harian matahari di Nusa penida, bisa sebagai  alternatif lain untuk sumber energi listrik dimana energi matahari bisa sebagai energi terbarukan untuk catu daya tambahan di BTS Nusa Penida yang pada akhirnya dapat menjaga  kestabilan suplai energi listrik ke BTS dan akses masyarakat terhadap informasi melalui seluler menjadi tidak terganggu. PV (Photovoltaic merupakan salah satu energi terbarukan yang dapat digunakan sebagai energi terbarukan untuk catu daya tambahan di BTS. Sistem PV yang dikembangkan untuk mensuplai energi listrik di BTS direncanakan sebesar 25%, adalah sistem PV yang hybrid dengan suplai listrik PLN. Besar daya PV yang dibangkitkan untuk mensuplai energi listrik di BTS adalah 9 kWp, yang dihasilkan dari panel PV sebanyak 45 panel dengan kapasitas panel PV adalah 200Wp dan kapasitas baterai yang akan digunakan adalah 3.800 Ah dengan total baterai 16. Analisis kelayakan investasi PV tanpa baterai dan PV dengan baterai yang dilakukan dengan menggunakan NPV, PI dan DPP menunjukkan hasil bahwa investasi PV layak untuk dilaksanakan. Untuk nilai NPV dan PI didapatkan kedua hasil investasi (> 0. Sedangkan untuk DPP didapatkan kedua hasil investasi dihasilkan lebih kecil dari periode umur proyek yang sudah ditetapkan, yaitu selama 25 tahun.

  15. INVESTIGATION WITH MODAL ANALYSIS OF EFFECTS OF HIGH PV PENETRATION ON POWER SYSTEM VOLTAGE STABILITY

    OpenAIRE

    YILDIRIM, Burak

    2017-01-01

    This paper shows the effects of high PVintegration on the power system voltage stability. PV power plant was appliedto the IEEE 30 bus test system. Modal analysis method is used to show theeffect of PV integration on power system voltage stability. The power rate ofsynchronous generator in the IEEE 30 bus system is increased to show the powersystem stability effect of high PV penetration and then the PV generation withthe same power rate is connected appropriate bus in power system. The modal...

  16. Environmental and exergy benefit of nanofluid-based hybrid PV/T systems

    International Nuclear Information System (INIS)

    Hassani, Samir; Saidur, R.; Mekhilef, Saad; Taylor, Robert A.

    2016-01-01

    Highlights: • Environmental and ExPBT analysis of different PV/T configurations is presented. • The exergy payback time of nanofluid-based hybrid PV/T system is about 2 years. • Nanofluid-based hybrid PV/T system is a reliable solution for pollution prevention. • Nanofluid-based hybrid PV/T system is highly recommended at high solar concentration. - Abstract: Photovoltaic/thermal (PV/T) solar systems, which produce both electrical and thermal energy simultaneously, represent a method to achieve very high conversion rates of sunlight into useful energy. In recent years, nanofluids have been proposed as efficient coolants and optical filter for PV/T systems. Aim of this paper is to theoretically analyze the life cycle exergy of three different configurations of nanofluids-based PV/T hybrid systems, and compare their performance to a standard PV and PV/T system. Electrical and thermal performance of the analyzed solar collectors was investigated numerically. The life cycle exergy analysis revealed that the nanofluids-based PV/T system showed the best performance compared to a standard PV and PV/T systems. At the optimum value of solar concentration C, nanofluid-based PV/T configuration with optimized optical and thermal properties produces ∼1.3 MW h/m 2 of high-grade exergy annually with the lowest exergy payback time of 2 years, whereas these are ∼0.36, ∼0.79 MW h/m 2 and 3.48, 2.55 years for standard PV and PV/T systems, respectively. In addition, the nanofluids-based PV/T system can prevent the emissions of about 448 kg CO 2 eq m −2 yr −1 . Overall, it was found that the nanofluids-based PV/T with optimized optical and thermal properties has potential for further development in a high-concentration solar system.

  17. Performance of a directly-coupled PV water pumping system

    International Nuclear Information System (INIS)

    Mokeddem, Abdelmalek; Midoun, Abdelhamid; Kadri, D.; Hiadsi, Said; Raja, Iftikhar A.

    2011-01-01

    Highlights: → Directly coupled PV water pumping system installed and performance studied. → Configured for two static heads, operate without electronic control and auxiliary power. → The system attains steady state soon after any abrupt change. → Cost effective and useful for low head communicating wells system. - Abstract: This paper describes the experimental study carried out to investigate the performance of a simple, directly coupled dc photovoltaic (PV) powered water pumping system. The system comprises of a 1.5 kWp PV array, dc motor and a centrifugal pump. The experiment was conducted over a period of 4 months and the system performance was monitored under different climatic conditions and varying solar irradiance with two static head configurations. Although the motor-pump efficiency did not exceed 30%, which is typical for directly-coupled photovoltaic pumping systems, such a system is clearly suitable for low head irrigation in the remote areas, not connected to the national grid and where access to water comes as first priority issue than access to technology. The system operates without battery and complex electronic control, therefore not only the initial cost is low but also maintenance, repairing and replacement cost can be saved. The study showed that directly coupled system attains steady state soon after any abrupt change.

  18. Five-year durability of stand-alone interspinous process decompression for lumbar spinal stenosis

    Directory of Open Access Journals (Sweden)

    Nunley PD

    2017-09-01

    Full Text Available Pierce D Nunley,1 Vikas V Patel,2 Douglas G Orndorff,3 William F Lavelle,4 Jon E Block,5 Fred H Geisler6 1Spine Institute of Louisiana, Shreveport, LA, 2The Spine Center, University of Colorado Hospital, Denver, CO, 3Spine Colorado, Mercy Regional Hospital, Durango, CO, 4Upstate Bone and Joint Center, East Syracuse, NY, 5Independent Consultant, San Francisco, CA, 6Independent Consultant, Chicago, IL, USA Background: Lumbar spinal stenosis is the most common indication for spine surgery in older adults. Interspinous process decompression (IPD using a stand-alone spacer that functions as an extension blocker offers a minimally invasive treatment option for intermittent neurogenic claudication associated with spinal stenosis.Methods: This study evaluated the 5-year clinical outcomes for IPD (Superion® from a randomized controlled US Food and Drug Administration (FDA noninferiority trial. Outcomes included Zurich Claudication Questionnaire (ZCQ symptom severity (ss, physical function (pf, and patient satisfaction (ps subdomains, leg and back pain visual analog scale (VAS, and Oswestry Disability Index (ODI.Results: At 5 years, 84% of patients (74 of 88 demonstrated clinical success on at least two of three ZCQ domains. Individual ZCQ domain success rates were 75% (66 of 88, 81% (71 of 88, and 90% (79 of 88 for ZCQss, ZCQpf, and ZCQps, respectively. Leg and back pain success rates were 80% (68 of 85 and 65% (55 of 85, respectively, and the success rate for ODI was 65% (57 of 88. Percentage improvements over baseline were 42%, 39%, 75%, 66%, and 58% for ZCQss, ZCQpf, leg and back pain VAS, and ODI, respectively (all P<0.001. Within-group effect sizes were classified as very large for four of five clinical outcomes (ie, >1.0; all P<0.0001. Seventy-five percent of IPD patients were free from reoperation, revision, or supplemental fixation at their index level at 5 years.Conclusion: After 5 years of follow-up, IPD with a stand-alone spacer provides

  19. Radiographic and clinical evaluation of cage subsidence after stand-alone lateral interbody fusion.

    Science.gov (United States)

    Marchi, Luis; Abdala, Nitamar; Oliveira, Leonardo; Amaral, Rodrigo; Coutinho, Etevaldo; Pimenta, Luiz

    2013-07-01

    Indirect decompression of the neural structures through interbody distraction and fusion in the lumbar spine is feasible, but cage subsidence may limit maintenance of the initial decompression. The influence of interbody cage size on subsidence and symptoms in minimally invasive lateral interbody fusion is heretofore unreported. The authors report the rate of cage subsidence after lateral interbody fusion, examine the clinical effects, and present a subsidence classification scale. The study was performed as an institutional review board-approved prospective, nonrandomized, comparative, single-center radiographic and clinical evaluation. Stand-alone short-segment (1- or 2-level) lateral lumbar interbody fusion was investigated with 12 months of postoperative follow-up. Two groups were compared. Forty-six patients underwent treatment at 61 lumbar levels with standard interbody cages (18 mm anterior/posterior dimension), and 28 patients underwent treatment at 37 lumbar levels with wide cages (22 mm). Standing lateral radiographs were used to measure segmental lumbar lordosis, disc height, and rate of subsidence. Subsidence was classified using the following scale: Grade 0, 0%-24% loss of postoperative disc height; Grade I, 25%-49%; Grade II, 50%-74%; and Grade III, 75%-100%. Fusion status was assessed on CT scanning, and pain and disability were assessed using the visual analog scale and Oswestry Disability Index. Complications and reoperations were recorded. Pain and disability improved similarly in both groups. While significant gains in segmental lumbar lordosis and disc height were observed overall, the standard group experienced less improvement due to the higher rate of interbody graft subsidence. A difference in the rate of subsidence between the groups was evident at 6 weeks (p = 0.027), 3 months (p = 0.042), and 12 months (p = 0.047). At 12 months, 70% in the standard group and 89% in the wide group had Grade 0 or I subsidence, and 30% in the standard group

  20. Design and control of a standalone PV water pumping system

    Directory of Open Access Journals (Sweden)

    Essam E. Aboul Zahab

    2017-09-01

    Full Text Available Water resources are vital for satisfying human needs. However, almost one-fifth of the world’s population – about 1.2 billion people – live in areas where water is physically rare. One quarter of the global population also live in developing countries that face water shortages. This paper presents standalone PV water pumping system. Photovoltaic (PV is the main power source, and lead acid batteries are used as energy storage system, to supply a water pump driven by a BLDC motor. The proposed control strategy consists of three control units. The first unit is to control the speed and hysteresis current controller for BLDC motor. The maximum power point tracking (MPPT is the second control unit, and the battery charging/discharging system is controlled by the third controller. The simulation results show the effectiveness and the good efficiency of the proposed system.

  1. Sizing PV-wind hybrid energy system for lighting

    Directory of Open Access Journals (Sweden)

    Mustafa Engin

    2012-09-01

    Full Text Available Sizing of wind and photovoltaic generators ensures lower operational costs and therefore, is considered as an important issue. An approach for sizing along with a best management technique for a PV-wind hybrid system with batteries is proposed in this paper, in which the best size for every component of the system could be optimized according to the weather conditions and the load profile. The average hourly values for wind speed and solar radiation for Izmir, Turkey has been used in the design of the systems, along with expected load profile. A hybrid power model is also developed for battery operation according to the power balance between generators and loads used in the software, to anticipate performances for the different systems according to the different weather conditions. The output of the program will display the performance of the system during the year, the total cost of the system, and the best size for the PV-generator, wind generator, and battery capacity. Using proposed procedure, a 1.2 kWp PV-wind hybrid system was designed for Izmir, and simulated and measured results are presented.

  2. Comparative Study Between Wind and Photovoltaic (PV) Systems

    Science.gov (United States)

    Taha, Wesam

    This paper reviews two renewable energy systems; wind and photovoltaic (PV) systems. The common debate between the two of them is to conclude which one is better, in terms of cost and efficiency. Therefore, comparative study, in terms of cost and efficiency, is attempted. Regarding total cost of both, wind and PV systems, many parameters must be taken into consideration such as availability of energy (either wind or solar), operation and maintenance, availability of costumers, political influence, and the components used in building the system. The main components and parameters that play major role in determining the overall efficiency of wind systems are the wind turbine generator (WTG), gearbox and control technologies such as power, and speed control. On the other hand, in grid-connected PV systems (GCPVS), converter architecture along with maximum power point tracking (MPPT) algorithm and inverter topologies are the issues that affects the efficiency significantly. Cost and efficiency analyses of both systems have been carried out based on the statistics available till today and would be useful in the progress of renewable energy penetration throughout the world.

  3. Flexible Control of Small Wind Turbines With Grid Failure Detection Operating in Stand-Alone and Grid-Connected Mode

    DEFF Research Database (Denmark)

    Teodorescu, Remus; Blaabjerg, Frede

    2004-01-01

    This paper presents the development and test of a flexible control strategy for an 11-kw wind turbine with a back-to-back power converter capable of working in both stand-alone and grid-connected mode. The stand-alone control is featured with a complex output voltage controller capable of handling...... nonlinear load and excess or deficit of generated power. Grid-connection mode with current control is also enabled for the case of isolated local grid involving other dispersed power generators such as other wind turbines or diesel generators. A novel automatic mode switch method based on a phase...

  4. Solar PV energy for water pumping system

    International Nuclear Information System (INIS)

    Mahar, F.

    1997-01-01

    The paper provides an introduction into understanding the relative merits, characteristics, including economics, of photovoltically powered water pumping systems. Although more than 10,000 photovoltaic pumping systems are known to be operating through out the world, many potential users do not know how to decide weather feasibility assessment, and system procurement so that the reader can made an informed decision about water pumping systems, especially those powered with photovoltaics. (author)

  5. Energy Yield of Tracking PV Systems in Jordan

    Directory of Open Access Journals (Sweden)

    A. Al Tarabsheh

    2012-01-01

    Full Text Available This paper analyzes the energy yield of photovoltaic (PV modules mounted on fixed tilt, one-axis, and two-axis tracking system towards maximizing the annual energy production. The performance evaluation of the proposed design of the tracking systems is carried via simulating the global radiation averages using METEONORM software and depicting the simulation results in figures using MATLAB software. The one-axis system is simulated by either fixing the azimuth angle while optimizing the inclination angles or fixing the inclination angle while optimizing the azimuth angles; simulation results show an increase in energy yield of 5.87% and 20.12% compared to that of fixed tilt system, respectively. In the two-axis system, optimization of both azimuth and inclination angles is carried out simultaneously which resulted in 30.82% improvement in energy yield. Therefore, 30% improvement in energy yield is directly reflected as saving in PV system cost due to reduction of the PV modules surface area.

  6. Development of a monitoring system for a PV solar plant

    International Nuclear Information System (INIS)

    Forero, N.; Hernandez, J.; Gordillo, G.

    2006-01-01

    The aim of this paper is to introduce a system developed for monitoring PV solar plants using a novel procedure based on virtual instrumentation. The measurements and processing of the data are made using high precision I/O modular field point (FP) devices as hardware, a data acquisition card as software and the package of graphic programming, LabVIEW. The system is able to store and display both the collected data of the environmental variables and the PV plant electrical output parameters, including the plant I-V curve. A relevant aspect of this work is the development of a unit that allows automatic measuring of the solar plant I-V curve using a car battery as power supply. The system has been in operation during the last two years and all its units have functioned well

  7. On the economics of stand-alone renewable hybrid power plants in remote regions

    International Nuclear Information System (INIS)

    Petrakopoulou, Fontina

    2016-01-01

    Highlights: • Economic evaluation of three renewable hybrid power plants for off-grid operation. • The high electricity cost of remote regions increases the competitiveness of renewable energy. • The proposed plants are economically viable when compared to the existing situation. • The zero direct emissions of the plants constitute an additional advantage of the plants. - Abstract: In recent years ever more examples of regions that have managed to achieve or orientate themselves toward renewable energy sufficiency are emerging. However, actions to create energy autonomy are mainly the result of isolated activities and they are less driven from fully organized movements. In addition, total energy independence without the support of a centralized electrical grid is yet to be achieved. The objectives of this work are to investigate the associated costs of stand-alone renewable hybrid power plants on a Greek island and compare them to the cost of the currently used fossil-fuel-based conventional plant. The plants examined here are designed to fully cover the electricity needs of the island. Islands may face numerous energy problems and rely heavily on foreign and environmentally-harmful fuels. It is shown that the relatively high cost of electricity of such a remote region can increase the competitiveness and promote the wider incorporation of technologies based on renewable energy sources that may, in other cases, seem economically inferior to business-as-usual energy solutions.

  8. Development of integrated CAD system PV-1

    International Nuclear Information System (INIS)

    Miyamoto, Hitoshi; Ogawa, Kazuya; Shibata, Masayoshi.

    1997-01-01

    An integrated CAD system for pressure vessels, such as heat exchangers, drums, towers, jacketed vessels, and tanks, has been developed. The system is operated by MS-DOS personal computers combined in a LAN. Pressure vessel designers can work watching using the computer display because the system automatically manages design work, on a common data base. The project team members in other sections, such as production, cost control, and design, have the same data concurrently. Personal computers unite the 3D CAD system, and the generated design with detail dimensions and shapes is stored in the 3D CAD system automatically. The system has promoted higher design quality and greatly reduced design cost. (author)

  9. MPC of Single Phase Inverter for PV System

    OpenAIRE

    Irtaza M. Syed; Kaamran Raahemifar

    2014-01-01

    This paper presents a model predictive control (MPC) of a utility interactive (UI) single phase inverter (SPI) for a photovoltaic (PV) system at residential/distribution level. The proposed model uses single-phase phase locked loop (PLL) to synchronize SPI with the grid and performs MPC control in a dq reference frame. SPI model consists of boost converter (BC), maximum power point tracking (MPPT) control, and a full bridge (FB) voltage source inverter (VSI). No PI regula...

  10. Model Predictive Control of Three Phase Inverter for PV Systems

    OpenAIRE

    Irtaza M. Syed; Kaamran Raahemifar

    2015-01-01

    This paper presents a model predictive control (MPC) of a utility interactive three phase inverter (TPI) for a photovoltaic (PV) system at commercial level. The proposed model uses phase locked loop (PLL) to synchronize the TPI with the power electric grid (PEG) and performs MPC control in a dq reference frame. TPI model consists of a boost converter (BC), maximum power point tracking (MPPT) control, and a three-leg voltage source inverter (VSI). The operational model of ...

  11. Fusion and subsidence rate of stand alone anterior lumbar interbody fusion using PEEK cage with recombinant human bone morphogenetic protein-2.

    Science.gov (United States)

    Behrbalk, Eyal; Uri, Ofir; Parks, Ruth M; Musson, Rachel; Soh, Reuben Chee Cheong; Boszczyk, Bronek Maximilian

    2013-12-01

    Anterior lumbar interbody fusion (ALIF) is an established treatment for structural instability associated with symptomatic disk degeneration (SDD). Stand-alone ALIF offers many advantages, however, it may increase the risk of non-union. Recombinant human bone morphogenetic protein-2 (BMP-2) may enhance fusion rate but is associated with postoperative complication. The optimal dose of BMP-2 remains unclear. This study assessed the fusion and subsidence rates of stand-alone ALIF using the SynFix-LR interbody cage with 6 ml/level of BMP-2. Thirty-two ALIF procedures were performed by a single surgeon in 25 patients. Twenty-five procedures were performed for SDD without spondylolisthesis (SDD group) and seven procedures were performed for SDD with grade-I olisthesis (SDD-olisthesis group). Patients were followed-up for a mean of 17 ± 6 months. Solid fusion was achieved in 29 cases (90.6 %) within 6 months postoperatively. Five cases of implant subsidence were observed (16 %). Four of these occurred in the SDD-olisthesis group and one occurred in the SDD group (57 % vs. 4 % respectively; p = 0.004). Three cases of subsidence failed to fuse and required revision. The body mass index of patients with olisthesis who developed subsidence was higher than those who did not develop subsidence (29 ± 2.6 vs. 22 ± 6.5 respectively; p = 0.04). No BMP-2 related complications occurred. The overall fusion rate of stand-alone ALIF using the SynFix-LR system with BMP-2 was 90.6 %, comparable with other published series. No BMP-2 related complication occurred at a dose of 6 mg/level. Degenerative spondylolisthesis and obesity seemed to increase the rate of implant subsidence, and thus we believe that adding posterior fusion for these cases should be considered.

  12. Single anterior cervical discectomy and fusion (ACDF) using self- locking stand-alone polyetheretherketone (PEEK) cage: evaluation of pain and health-related quality of life.

    Science.gov (United States)

    Kapetanakis, Stylianos; Thomaidis, Tryfon; Charitoudis, George; Pavlidis, Pavlos; Theodosiadis, Panagiotis; Gkasdaris, Grigorios

    2017-09-01

    Anterior cervical discectomy and fusion (ACDF) constitutes the conventional treatment of cervical disc herniation due to degenerative disc disease (DDD). ACDF with plating presents a variety of complications postoperatively and stand-alone cages are thought to be a promising alternative. The aim of this study was firstly, to analyze prospectively collected data from a sample of patients treated with single ACDF using C-Plus self-locking stand-alone PEEK cage system, without the use of plates or screws, in order to evaluate pain levels of patients, utilizing Neck and Arm Pain scale as an expression of visual analogue scale (VAS). Secondly, we aimed to evaluate health-related quality of life, via the short-form 36 (SF-36) and Neck Disability Index (NDI). Thirty-six patients (19 male and 17 female) with mean age 49.6±7 years old who underwent successful single ACDF using self-locking stand-alone PEEK cage for symptomatic cervical DDD were selected for the study. Neck and Arm pain, as well as SF-36 and NDI were estimated preoperatively and 1, 3, 6, and 12 months postoperatively. Patients underwent preoperative and postoperative clinical, neurological and radiological evaluation. The clinical and radiological outcomes were satisfactory after a minimum 1-year follow-up. All results were statistically important (P<0.05), excluding improvement in NDI measured between 6 and 12 months. SF-36, Neck Pain, as well as Arm Pain featured gradual and constant improvement during follow-up, with best scores presenting at 12 months after surgery, while NDI reached its best at 6 months postoperatively. Generally, all scores showed improvement postoperatively during the different phases of the follow-up. Subsequently, ACDF using C-Plus cervical cage constitutes an effective method for cervical disc herniation treatment, in terms of postoperative improvement on pain levels and health-related quality of life and a safe alternative to the conventional method of treatment for cervical DDD.

  13. PV Charging System for Remote Area Operations

    Energy Technology Data Exchange (ETDEWEB)

    Ilsemann, Frederick [Coherent Systems International, Doylestown, PA (United States); Thompson, Roger [Coherent Systems International, Doylestown, PA (United States)

    2008-07-31

    The objective of this project is to provide the public with a study of new as well existing technology to recharge batteries used in the field. A new product(s) will also be built based upon the information ascertained. American Electric Vehicles, Inc. (AEV) developed systems and methods suitable for charging state-of-the-art lithium-ion batteries in remote locations under both ideal and cloudy weather conditions. Conceptual designs are described for existing and next generation technology, particularly as regards solar cells, peak power trackers and batteries. Prototype system tests are reported.

  14. Motion Sensorless Bidirectional PWM Converter Control with Seamless Switching from Power Grid to Stand Alone and Back

    DEFF Research Database (Denmark)

    Fatu, Marius; Tutelea, Lucian; Teodorescu, Remus

    2007-01-01

    This paper presents concepts and tests results on a flexible sensorless control strategy for a PMSG driven by a small wind turbine with back-to-back power converters capable to function in both stand alone and grid connection mode. A new automatic seamless transfer method, based on phase-locked...

  15. Stand-Alone Ethics, Social Responsibility, and Sustainability Course Requirements: A Snapshot from Australia and New Zealand

    Science.gov (United States)

    Rundle-Thiele, Sharyn R.; Wymer, Walter

    2010-01-01

    This article analyzes the extent to which Australian and New Zealand marketing educators use dedicated or stand-alone courses to equip students with alternative views of business. A census of marketing programs in degree-granting universities was conducted. Program brochures were obtained via the Internet and were content analyzed. This study…

  16. 49 CFR 1109.4 - Mandatory mediation in rate cases to be considered under the stand-alone cost methodology.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 8 2010-10-01 2010-10-01 false Mandatory mediation in rate cases to be considered... § 1109.4 Mandatory mediation in rate cases to be considered under the stand-alone cost methodology. (a) A... methodology must engage in non-binding mediation of its dispute with the railroad upon filing a formal...

  17. How PV system ownership can impact the market value of residential homes

    Energy Technology Data Exchange (ETDEWEB)

    Klise, Geoffrey Taylor [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Johnson, Jamie L. [Energy Sense Finance, LLC, Punta Gorda, FL (United States)

    2014-01-01

    There are multiple ways for a homeowner to obtain the electricity generating and savings benefits offered by a photovoltaic (PV) system. These include purchasing a PV system through various financing mechanisms, or by leasing the PV system from a third party with multiple options that may include purchase, lease renewal or PV system removal. The different ownership options available to homeowners presents a challenge to appraisal and real estate professionals during a home sale or refinance in terms of how to develop a value that is reflective of the PV systems operational characteristics, local market conditions, and lender and underwriter requirements. This paper presents these many PV system ownership options with a discussion of what considerations an appraiser must make when developing the contributory value of a PV system to a residential property.

  18. Photovoltaic solar panel for a hybrid PV/thermal system

    Energy Technology Data Exchange (ETDEWEB)

    Zakharchenko, R.; Licea-Jimenez, L.; Perez-Garcia, S.A.; Perez-Robles, J.F.; Gonzalez-Hernandez, J.; Vorobiev, Y. [CINVESTAV-Queretaro, (Mexico); Vorobiev, P. [Universidad Autonoma de Queretaro, (Mexico). Facultad de Ingenieria; Dehesa-Carrasco, U. [Instituto Tec. Del Istmo, Oaxaco (Mexico). Dep. de Ingenieria Electromecanica

    2004-05-01

    The hybrid PV-thermal system was studied, with the photovoltaic panel (PVP) area much smaller than that of the solar collector. Performance of the different panels in the system was investigated, in particular, those made of crystalline (c-) Si, {alpha}-Si and CuInSe{sub 2} as well as different materials and constructions for the thermal contact between the panel and the collector. Our conclusion is that the PVP for application in a hybrid system needs a special design providing efficient heat extraction from it. PVP was designed and made. Its study has shown that this design provides the high electrical and thermal efficiency of the hybrid system. (author)

  19. Radiologic Assessment of Subsidence in Stand-Alone Cervical Polyetheretherketone (PEEK) Cage.

    Science.gov (United States)

    Ha, Sung-Kon; Park, Jung-Yul; Kim, Se-Hoon; Lim, Dong-Jun; Kim, Sang-Dae; Lee, Sang-Kook

    2008-12-01

    Aim of study was to find a proper method for assessing subsidence using a radiologic measurement following anterior cervical discectomy and fusion (ACDF) with stand-alone polyetheretherketone (PEEK), Solistrade mark cage. Forty-two patients who underwent ACDF with Solistrade mark cage were selected. With a minimum follow-up of 6 months, the retrospective investigation was conducted for 37 levels in 32 patients. Mean follow-up period was 18.9 months. Total intervertebral height (TIH) of two fused vertebral bodies was measured on digital radiographs with built-in software. Degree of subsidence (DeltaTIH) was reflected by the difference between the immediate postoperative and follow-up TIH. Change of postoperative disc space height (CT-MRDeltaTIH) was reflected by the difference between TIH of the preoperative mid-sagittal 2D CT and that of the preoperative mid-sagittal T1-weighted MRI. Compared to preoperative findings, postoperative disc height was increased in all cases and subsidence was observed only in 3 cases. For comparison of subsidence and non-subsidence group, TIH and CT-MRDeltaTIH of each group were analyzed. There was no statistically significant difference in TIH and CT-MRDeltaTIH between each group at 4 and 8 weeks, but a difference was observed at the last follow-up TIH (p=0.0497). ACDF with Solistrade mark cage was associated with relatively good radiologic long-term results. Fusion was achieved in 94.5% and subsidence occurred in 8.1% by the radiologic assessment. Statistical analysis reveals that the subsidence seen later than 8 weeks after surgery and the development of subsidence does not correlate statistically with the change of the postoperative disc space height.

  20. Stand-Alone Lateral Interbody Fusion for the Treatment of Low-Grade Degenerative Spondylolisthesis

    Directory of Open Access Journals (Sweden)

    Luis Marchi

    2012-01-01

    Full Text Available The purpose of this paper was to investigate the stand-alone lateral interbody fusion as a minimally invasive option for the treatment of low-grade degenerative spondylolisthesis with a minimum 24-month followup. Prospective nonrandomized observational single-center study. 52 consecutive patients (67.6±10 y/o; 73.1% female; 27.4±3.4 BMI with single-level grade I/II single-level degenerative spondylolisthesis without significant spine instability were included. Fusion procedures were performed as retroperitoneal lateral transpsoas interbody fusions without screw supplementation. The procedures were performed in average 73.2 minutes and with less than 50cc blood loss. VAS and Oswestry scores showed lasting improvements in clinical outcomes (60% and 54.5% change, resp.. The vertebral slippage was reduced in 90.4% of cases from mean values of 15.1% preoperatively to 7.4% at 6-week followup (P<0.001 and was maintained through 24 months (7.1%, P<0.001. Segmental lordosis (P<0.001 and disc height (P<0.001 were improved in postop evaluations. Cage subsidence occurred in 9/52 cases (17% and 7/52 cases (13% spine levels needed revision surgery. At the 24-month evaluation, solid fusion was observed in 86.5% of the levels treated. The minimally invasive lateral approach has been shown to be a safe and reproducible technique to treat low-grade degenerative spondylolisthesis.

  1. "Candidatus Fokinia solitaria", a Novel "Stand-Alone" Symbiotic Lineage of Midichloriaceae (Rickettsiales.

    Directory of Open Access Journals (Sweden)

    Franziska Szokoli

    Full Text Available Recently, the family Midichloriaceae has been described within the bacterial order Rickettsiales. It includes a variety of bacterial endosymbionts detected in different metazoan host species belonging to Placozoa, Cnidaria, Arthropoda and Vertebrata. Representatives of Midichloriaceae are also considered possible etiological agents of certain animal diseases. Midichloriaceae have been found also in protists like ciliates and amoebae. The present work describes a new bacterial endosymbiont, "Candidatus Fokinia solitaria", retrieved from three different strains of a novel Paramecium species isolated from a wastewater treatment plant in Rio de Janeiro (Brazil. Symbionts were characterized through the full-cycle rRNA approach: SSU rRNA gene sequencing and fluorescence in situ hybridization (FISH with three species-specific oligonucleotide probes. In electron micrographs, the tiny rod-shaped endosymbionts (1.2 x 0.25-0.35 μm in size were not surrounded by a symbiontophorous vacuole and were located in the peripheral host cytoplasm, stratified in the host cortex in between the trichocysts or just below them. Frequently, they occurred inside autolysosomes. Phylogenetic analyses of Midichloriaceae apparently show different evolutionary pathways within the family. Some genera, such as "Ca. Midichloria" and "Ca. Lariskella", have been retrieved frequently and independently in different hosts and environmental surveys. On the contrary, others, such as Lyticum, "Ca. Anadelfobacter", "Ca. Defluviella" and the presently described "Ca. Fokinia solitaria", have been found only occasionally and associated to specific host species. These last are the only representatives in their own branches thus far. Present data do not allow to infer whether these genera, which we named "stand-alone lineages", are an indication of poorly sampled organisms, thus underrepresented in GenBank, or represent fast evolving, highly adapted evolutionary lineages.

  2. A MPPT Algorithm Based PV System Connected to Single Phase Voltage Controlled Grid

    Science.gov (United States)

    Sreekanth, G.; Narender Reddy, N.; Durga Prasad, A.; Nagendrababu, V.

    2012-10-01

    Future ancillary services provided by photovoltaic (PV) systems could facilitate their penetration in power systems. In addition, low-power PV systems can be designed to improve the power quality. This paper presents a single-phase PV systemthat provides grid voltage support and compensation of harmonic distortion at the point of common coupling thanks to a repetitive controller. The power provided by the PV panels is controlled by a Maximum Power Point Tracking algorithm based on the incremental conductance method specifically modified to control the phase of the PV inverter voltage. Simulation and experimental results validate the presented solution.

  3. Rooftop PV system. Final technical progress report, Phase II

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-08-01

    Under this four-year PV:BONUS Program, ECD and United Solar are developing and demonstrating two new lightweight flexible building integrated Photovoltaic (BIPV) modules specifically designed as exact replacements for conventional asphalt shingles and standing seam metal roofing. These modules can be economically and aesthetically integrated into new residential and commercial buildings, and address the even larger roofing replacement market. The modules are designed to be installed by roofing contractors without special training which minimizes the installation and balance of system costs. The modules will be fabricated from high-efficiency, multiple-junction a-Si alloy solar cells developed by ECD and United Solar. Under the Phase I Program, which ended in March 1994, we developed two different concept designs for rooftop PV modules: (1) the United Solar overlapping (asphalt shingle replacement) shingle-type modules and (2) the ECD metal roof-type modules. We also developed a plan for fabricating, testing and demonstrating these modules. Candidate demonstration sites for our rooftop PV modules were identified and preliminary engineering designs for these demonstrations were developed; a marketing study plan was also developed. The major objectives of the Phase II Program, which started in June 1994 was (1) to develop, test, and qualify these new rooftop modules; (2) to develop mechanical and electrical engineering specifications for the demonstration projects; and (3) to develop a marketing/commercialization plan.

  4. Sizing procedures for sun-tracking PV system with batteries

    Science.gov (United States)

    Nezih Gerek, Ömer; Başaran Filik, Ümmühan; Filik, Tansu

    2017-11-01

    Deciding optimum number of PV panels, wind turbines and batteries (i.e. a complete renewable energy system) for minimum cost and complete energy balance is a challenging and interesting problem. In the literature, some rough data models or limited recorded data together with low resolution hourly averaged meteorological values are used to test the sizing strategies. In this study, active sun tracking and fixed PV solar power generation values of ready-to-serve commercial products are recorded throughout 2015-2016. Simultaneously several outdoor parameters (solar radiation, temperature, humidity, wind speed/direction, pressure) are recorded with high resolution. The hourly energy consumption values of a standard 4-person household, which is constructed in our campus in Eskisehir, Turkey, are also recorded for the same period. During sizing, novel parametric random process models for wind speed, temperature, solar radiation, energy demand and electricity generation curves are achieved and it is observed that these models provide sizing results with lower LLP through Monte Carlo experiments that consider average and minimum performance cases. Furthermore, another novel cost optimization strategy is adopted to show that solar tracking PV panels provide lower costs by enabling reduced number of installed batteries. Results are verified over real recorded data.

  5. Solar PV Manufacturing Cost Model Group: Installed Solar PV System Prices (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Goodrich, A. C.; Woodhouse, M.; James, T.

    2011-02-01

    EERE's Solar Energy Technologies Program is charged with leading the Secretary's SunShot Initiative to reduce the cost of electricity from solar by 75% to be cost competitive with conventional energy sources without subsidy by the end of the decade. As part of this Initiative, the program has funded the National Renewable Energy Laboratory (NREL) to develop module manufacturing and solar PV system installation cost models to ensure that the program's cost reduction targets are carefully aligned with current and near term industry costs. The NREL cost analysis team has leveraged the laboratories' extensive experience in the areas of project finance and deployment, as well as industry partnerships, to develop cost models that mirror the project cost analysis tools used by project managers at leading U.S. installers. The cost models are constructed through a "bottoms-up" assessment of each major cost element, beginning with the system's bill of materials, labor requirements (type and hours) by component, site-specific charges, and soft costs. In addition to the relevant engineering, procurement, and construction costs, the models also consider all relevant costs to an installer, including labor burdens and overhead rates, supply chain costs, and overhead and materials inventory costs, and assume market-specific profits.

  6. Results from measurements on the PV-VENT systems at Lundebjerg[DENMARK

    Energy Technology Data Exchange (ETDEWEB)

    Oestergaard Jensen, S.

    2001-05-01

    The objective of the PV-VENT project was research, development, and tests in the following areas: 1. Develop and illustrate different ways of architectural integration of solar energy systems with combined PV power production and pre-heating of ventilation air in buildings, 2. Investigate the potential in pre-heating fresh air to the building by cooling the PV-panels with the fresh air and further to determine how much this cooling will increase the electrical performance of the PV-panels, 3. Develop and test air to air heat exchangers with an efficiency of 80% or above, 4. Develop and test fans and ventilation systems with an overall fan power demand of about 35 W, 5. Develop and test a direct coupling of the PV-panels to the fans in order to avoid the losses in an inverter, 6. Develop and test different ventilation systems utilizing the abovementioned features. Three different ways of integrating PV-panels with pre-heating of fresh air to the building have been demonstrated in Lundebjerg: a large PV-gable with amorphous PV-panels, a PV-facade with polycrystalline (c-Si) PV-panels and solar ventilation chimneys with polycrystalline (c-Si) PV-panels. Especially the latter feature, the solar ventilation chimney is a new and interesting concept as it allows for increased PV areas although the orientation of the building is not optimal for utilization of solar energy, as was the case in Lundebjerg. It is believed that the PV-VENT project has added important information and experience to the field of combining PV and ventilation systems. Information and experience that future systems of this type may benefit from. Several of the components from the project are believed to be able to contribute to set the standards for future PV and ventilation systems. Several of the components from the project is today commercial available and are used in ordinary building projects. (BA)

  7. A Software Tool for Optimal Sizing of PV Systems in Malaysia

    Directory of Open Access Journals (Sweden)

    Tamer Khatib

    2012-01-01

    Full Text Available This paper presents a MATLAB based user friendly software tool called as PV.MY for optimal sizing of photovoltaic (PV systems. The software has the capabilities of predicting the metrological variables such as solar energy, ambient temperature and wind speed using artificial neural network (ANN, optimizes the PV module/ array tilt angle, optimizes the inverter size and calculate optimal capacities of PV array, battery, wind turbine and diesel generator in hybrid PV systems. The ANN based model for metrological prediction uses four meteorological variables, namely, sun shine ratio, day number and location coordinates. As for PV system sizing, iterative methods are used for determining the optimal sizing of three types of PV systems, which are standalone PV system, hybrid PV/wind system and hybrid PV/diesel generator system. The loss of load probability (LLP technique is used for optimization in which the energy sources capacities are the variables to be optimized considering very low LLP. As for determining the optimal PV panels tilt angle and inverter size, the Liu and Jordan model for solar energy incident on a tilt surface is used in optimizing the monthly tilt angle, while a model for inverter efficiency curve is used in the optimization of inverter size.

  8. The microcomputer-based expert system in CAD-PV

    International Nuclear Information System (INIS)

    Wang, Y.; Qin, S.

    1987-01-01

    As a branch of artificial intelligence, expert system has been revealed day after day in more and more engineering scopes since the successful applications of MYCIN in diagnosis and DENDRAL in the molecular structure of organic compounds etc.. But in the design scope of pressure vessel, as we know, only a few papers have so far been published with respect to the expert system. The necessity and feasibility of accompanying CAD-PV with expert system attracted more scholars to engage in. Although many countries, including China, have regularized the design standards or codes for pressure vessel, but of which no one can solve all of the problems concerning the various practical occasions and experiences. In general, the more domain knowledges a design engineer possesses of, the better decision will be made by him. By virtue of the expert system any less experienced engineer could make the optimum decision in design as well as a skilled senior engineer in addition to the application of design code. It is the due significance for developing high level expert system as an intelligence assistant in the plan option of CAD-PV. In this paper we attempt to introduce a specified software JACKPV used in the design procedure of jacketed pressure vessel as an intelligence front in CAD-PV. JACKPV consists of the function of expert system based on the personal computer IBM-PC/XT with the language PASCAL in its program. It was proved that an ordinary CAD software could be effectively improved while equipped with expert system. (orig.)

  9. Energetic and financial investigation of a stand-alone solar-thermal Organic Rankine Cycle power plant

    International Nuclear Information System (INIS)

    Tzivanidis, Christos; Bellos, Evangelos; Antonopoulos, Kimon A.

    2016-01-01

    Highlights: • A stand-alone solar driven Organic Rankine Cycle is optimized parametrically. • The system is optimized energetically and financially. • Nine working fluids are tested with cyclohexane to be the most suitable. • A collecting area of 25,000 m 2 parabolic trough collectors is the optimum solution. • The maximum IRR is 13.46% and the payback period is about 9 years. - Abstract: The use of solar thermal energy for electricity production is a clean and sustainable way to cover the increasing energy needs of our society. The most mature technology for capturing solar energy in high temperature levels is the parabolic trough collectors (PTC). In this study, an Organic Rankine Cycle (ORC) coupled with PTC is analyzed parametrically in order to be optimized financially and energetically. The first step is the thermodynamic investigation of the ORC by using various working fluids. The second step is the energetic and financial investigation of the total system which includes the solar field, the storage tank and the ORC module. By testing many combinations of collecting areas and storage tank volumes, finally cyclohexane proved to be the most suitable working fluid for producing 1 MW el with PTC. Specifically, in the optimum situation a solar field of 25,000 m 2 with storage tank of about 300 m 3 leads to a payback period of 9 years and to an internal rate of return (IRR) equal to 13.46%. Moreover, an economic comparison for different commercial collectors is presented, with Eurotrough ET-150 being the financially optimum solution for this case study.

  10. Sizing and Simulation of PV-Wind Hybrid Power System

    Directory of Open Access Journals (Sweden)

    Mustafa Engin

    2013-01-01

    Full Text Available A sizing procedure is developed for hybrid system with the aid of mathematical models for photovoltaic cell, wind turbine, and battery that are readily present in the literature. This sizing procedure can simulate the annual performance of different kinds of photovoltaic-wind hybrid power system structures for an identified set of renewable resources, which fulfills technical limitations with the lowest energy cost. The output of the program will display the performance of the system during the year, the total cost of the system, and the best size for the PV-generator, wind generator, and battery capacity. Security lightning application is selected, whereas system performance data and environmental operating conditions are measured and stored. This hybrid system, which includes a PV, wind turbine, inverter, and a battery, was installed to supply energy to 24 W lamps, considering that the renewable energy resources of this site where the system was installed were 1700 Wh/m2/day solar radiation and 3.43 m/s yearly average wind speed. Using the measured variables, the inverter and charge regulator efficiencies were calculated as 90% and 98%, respectively, and the overall system’s electrical efficiency is calculated as 72%. Life cycle costs per kWh are found to be $0.89 and LLP = 0.0428.

  11. Harmonic analysis and suppression in hybrid wind & PV solar system

    Science.gov (United States)

    Gupta, Tripti; Namekar, Swapnil

    2018-04-01

    The growing demand of electricity has led to produce power through non-conventional source of energy such as solar energy, wind energy, hydro power, energy through biogas and biomass etc. Hybrid system is taken to complement the shortcoming of either sources of energy. The proposed system is grid connected hybrid wind and solar system. A 2.1 MW Doubly fed Induction Generator (DFIG) has been taken for analysis of wind farm whose rotor part is connected to two back-to-back converters. A 250 KW Photovoltaic (PV) array taken to analyze solar farm where inverter is required to convert power from DC to AC since electricity generated through solar PV is in the form of DC. Stability and reliability of the system is very important when the system is grid connected. Harmonics is the major Power quality issue which degrades the quality of power at load side. Harmonics in hybrid system arise through the use of power conversion unit. The other causes of harmonics are fluctuation in wind speed and solar irradiance. The power delivered to grid must be free from harmonics and within the limits specified by Indian grid codes. In proposed work, harmonic analysis of the hybrid system is performed in Electrical Transient Analysis program (ETAP) and single tuned harmonic filter is designed to maintain the utility grid harmonics within limits.

  12. Rooftop PV system. PV:BONUS Phase 3B, final technical report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-11-01

    Under the PV:BONUS Program, ECD and United Solar developed, demonstrated and commercialized two new lightweight, flexible BIPV modules specifically designed as replacements for conventional asphalt shingles and standing seam metal roofing. These modules can be economically and aesthetically integrated into new residential and commercial buildings, and can be used to address the even larger roofing-replacement market. An important design feature of these modules, which minimizes the installation and balance-of-system costs, is their ability to be installed by conventional roofing contractors without special training. The modules are fabricated from high-efficiency, triple-junction spectrum-splitting a-Si alloy solar cells developed by ECD and United Solar. These cells are produced on thin, flexible stainless steel substrates and encapsulated with polymer materials. The Phase 3 program began in August 1995. The principal tasks and goals of this program, which have all been successfully completed by ECD and United Solar, are described in the body and appendices of this report.

  13. [Biomechanicsl evaluation of a stand-alone interbody fusion cage based on porous TiO2/glass-ceramic on the human cervical spine].

    Science.gov (United States)

    Korinth, M C; Moersch, S; Ragoss, C; Schopphoff, E

    2003-12-01

    Recently, there has been a rapid increase in the use of cervical spine interbody fusion cages, differing in design and biomaterial used, in competition to autologous iliac bone graft and bone cement (PMMA). Limited biomechanical differences in primary stability, as well as advantages and disadvantages of each cage or material have been investigated in studies, using an in vitro human cervical spine model. 20 human cervical spine specimens were tested after fusion with either a cubical stand-alone interbody fusion cage manufactured from a new porous TiO2/glass composite (Ecopore) or PMMA after discectomy. Non-destructive biomechanical testing was performed, including flexion/extension and lateral bending using a spine testing apparatus. Three-dimensional segmental range of motion (ROM) was evaluated using an ultrasound measurement system. ROM increased more in flexion/extension and lateral bending after PMMA fusion (26.5%/36.1%), then after implantation of the Ecopore-cage (8.1%/7.8%). In this first biomechanical in vitro examination of a new porous ceramic bone replacement material a) the feasibility and reproducibility of biomechanical cadaveric cervical examination and its applicability was demonstrated, b) the stability of the ceramic cage as a stand alone interbody cage was confirmed in vitro, and c) basic information and knowledge for our intended biomechanical and histological in vivo testing, after implantation of Ecopore in cervical sheep spines, were obtained.

  14. Design of direct solar PV driven air conditioner

    KAUST Repository

    Huang, Bin-Juine

    2015-12-05

    © 2015 Elsevier Ltd. Solar air conditioning system directly driven by stand-alone solar PV is studied. The air conditioning system will suffer from loss of power if the solar PV power generation is not high enough. It requires a proper system design to match the power consumption of air conditioning system with a proper PV size. Six solar air conditioners with different sizes of PV panel and air conditioners were built and tested outdoors to experimentally investigate the running probabilities of air conditioning at various solar irradiations. It is shown that the instantaneous operation probability (OPB) and the runtime fraction (RF) of the air conditioner are mainly affected by the design parameter rpL (ratio of maximum PV power to load power). The measured OPB is found to be greater than 0.98 at instantaneous solar irradiation IT > 600 W m-2 if rpL > 1.71 RF approaches 1.0 (the air conditioner is run in 100% with solar power) at daily-total solar radiation higher than 13 MJ m-2 day-1, if rpL > 3.

  15. Theoretical analysis and experimental study on the PV-IESAHP system

    Science.gov (United States)

    Wu, Xingying

    2017-05-01

    Solar photovoltaic/thermal integration (PV/T) and heat pump are very important techniques for energy conservation and carbon reduction. A practical design for an integrated PV/T and heat pump system is presented, the integrated system is called the Photovoltaic-Indirect Expansion Solar Assisted Heat Pump (PV-IESAHP) system, which uses the heat energy supplied by PV/T as an evaporating heat source and can achieve high coefficient of performance(COP). It is essential to master the completed design idea and thermodynamic analysis method for the integration of PV/T and heat pump. In this study a kind of theoretical and matching performance model of the PV-IESAHP system is established, and a series of experiments were conducted to study the performance of the heat-pipe type PV/T experimental system and heat hump experimental system. Moreover, energy and energy analyses were used to investigate the performance of the systems. The results show that the COP of the PV-IESAHP system is about 4.0, and the energy efficiency about 0.05, which not only implies that the PV-IESAHP system has a significant energy-saving potential, but also will provide a theoretical basis for the application and parameters design of the PV-IESAHP system in the future.

  16. Assuring long-term reliability of concentrator PV systems

    Science.gov (United States)

    McConnell, R.; Garboushian, V.; Brown, J.; Crawford, C.; Darban, K.; Dutra, D.; Geer, S.; Ghassemian, V.; Gordon, R.; Kinsey, G.; Stone, K.; Turner, G.

    2009-08-01

    Concentrator PV (CPV) systems have attracted significant interest because these systems incorporate the world's highest efficiency solar cells and they are targeting the lowest cost production of solar electricity for the world's utility markets. Because these systems are just entering solar markets, manufacturers and customers need to assure their reliability for many years of operation. There are three general approaches for assuring CPV reliability: 1) field testing and development over many years leading to improved product designs, 2) testing to internationally accepted qualification standards (especially for new products) and 3) extended reliability tests to identify critical weaknesses in a new component or design. Amonix has been a pioneer in all three of these approaches. Amonix has an internal library of field failure data spanning over 15 years that serves as the basis for its seven generations of CPV systems. An Amonix product served as the test CPV module for the development of the world's first qualification standard completed in March 2001. Amonix staff has served on international standards development committees, such as the International Electrotechnical Commission (IEC), in support of developing CPV standards needed in today's rapidly expanding solar markets. Recently Amonix employed extended reliability test procedures to assure reliability of multijunction solar cell operation in its seventh generation high concentration PV system. This paper will discuss how these three approaches have all contributed to assuring reliability of the Amonix systems.

  17. prfectBLAST: a platform-independent portable front end for the command terminal BLAST+ stand-alone suite.

    Science.gov (United States)

    Santiago-Sotelo, Perfecto; Ramirez-Prado, Jorge Humberto

    2012-11-01

    prfectBLAST is a multiplatform graphical user interface (GUI) for the stand-alone BLAST+ suite of applications. It allows researchers to do nucleotide or amino acid sequence similarity searches against public (or user-customized) databases that are locally stored. It does not require any dependencies or installation and can be used from a portable flash drive. prfectBLAST is implemented in Java version 6 (SUN) and runs on all platforms that support Java and for which National Center for Biotechnology Information has made available stand-alone BLAST executables, including MS Windows, Mac OS X, and Linux. It is free and open source software, made available under the GNU General Public License version 3 (GPLv3) and can be downloaded at www.cicy.mx/sitios/jramirez or http://code.google.com/p/prfectblast/.

  18. Firefighter safety for PV systems: Overview of future requirements and protection systems

    DEFF Research Database (Denmark)

    Spataru, Sergiu; Sera, Dezso; Blaabjerg, Frede

    2013-01-01

    for operators during maintenance or fire-fighting. One of the solutions is individual module shutdown by short-circuiting or disconnecting each PV module from the PV string. However, currently no standards have been adopted either for implementing or testing these methods, or doing an evaluation of the module...... shutdown procedures. This paper gives an overview on the most recent fire - and firefighter safety requirements for PV systems, with focus on system and module shutdown systems. Several solutions are presented, analyzed and compared by considering a number of essential characteristics, including...... their transient behavior, components' voltage stress and conduction losses....

  19. Consequences of Reducing the Cost of PV Modules on a PV Wind Diesel Hybrid System with Limited Sizing Components

    Directory of Open Access Journals (Sweden)

    Jones S. Silva

    2012-01-01

    Full Text Available The use of renewable resources for power supply in family homes has passed the stage of utopia to became a reality, with limits set by technical and economic parameters. This paper presents the results of a project originated from the initiative of a middle-class family to achieve energy independence at home. The starting point was the concept of home with “zero energy” in which the total energy available is equal to the energy consumed. The solution devised to meet the energy demand of the residence in question is a PV wind diesel hybrid system connected to the grid, with the possibility of energy storage in batteries and in the form of heating water and the environment of the house. As a restriction, the family requested that the system would represent little impact to the lifestyle and landscape. This paper aims to assess the consequences of reductions in the cost of the PV modules on the optimization space, as conceived by the software Homer. The results show that for this system, a 50% reduction in the cost of PV modules allows all viable solutions including PV modules.

  20. An Economic Analysis of Residential PV System for Adiyaman, Turkey

    Directory of Open Access Journals (Sweden)

    Haci SOGUKPINAR

    2015-07-01

    Full Text Available Solar energy constitutes the main source of all energy sources and it is one of the most important renewable energy sources in terms of huge potential. As with other energy sources not just in certain places in the world, everywhere have the potential where the sun rises and set. Turkey is located on the sunny area and solar energy generation is quite rich in potential. Together with the substantial increase in the efficiency of photovoltaic cells, generating electricity from solar energy is becoming increasingly common. Especially in places where no grid connection, photovoltaic cells is very useful in supplying the energy needs. In this study, Turkey's solar energy potential was analyzed, and PV systems to meet the electricity needs of a home were analyzed economically. Consequently, to meet the electricity needs of a house in Adiyaman conditions that require a surface area of 24 m2 with a PV system, and this system was determined to be able to amortize itself in 10 years.

  1. Lighting up the villages: Livelihood impacts of decentralized stand-alone solar photovoltaic electrification in rural northern Ghana

    Directory of Open Access Journals (Sweden)

    Naah John-Baptist Saabado Ngmaadaba

    2015-01-01

    Full Text Available The dynamics of solar photovoltaic (PV technology dissemination and utilization has taken center stage in recent years on a global scale, aiming to partly address prevailing rampant energy poverty situations particularly in developing countries. This paper evaluates a flagship electrification project called Ghana Energy Development and Access Project (GEDAP. We purposively sampled 250 solar users in 65 villages across 6 districts in the Upper West region which has the country’s lowest level of electricity access and possibly the highest proportion of abject poverty among its inhabitants compared to the rest of the country. Based on the survey, it can be said that the overall impact assessment of the GEDAP-sponsored off-grid solar PV systems on the quality of life of the local beneficiaries was found to be positively marginal. Among all livelihood assets considered, social capital was markedly enhanced by the provision of modern energy services via isolated solar PV systems. Bottlenecks were identified, including limited system wattage capacity, slight dysfunction of some balance of components, higher interest rates, low technical know-how and inadequate monitoring, all of which are negatively affecting the sustainability of the project. Our findings also indicate that satisfaction derived from solar PV electricity supply among local solar customers differed for varied reasons as follows: moderately satisfied (43%, satisfied (52%, and dissatisfied (5%. For a decisive enhancement of rural livelihoods, we strongly recommend up-scaling system wattage capacity and coverage to build up new or improve upon existing livelihood assets through diversification of the income sources of the local inhabitants.

  2. System performance of a three-phase PV-grid-connected system installed in Thailand. Data monitored analysis

    International Nuclear Information System (INIS)

    Boonmee, Chaiyant; Watjanatepin, Napat; Plangklang, Boonyang

    2009-01-01

    PV-grid-connected systems are worldwide installed because it allows consumer to reduce energy consumption from the electricity grid and to feed the surplus energy back into the grid. The system needs no battery so therefore the system price is very cheap comparing to other PV systems. PV-grid-connected systems are used in buildings that already hooked up to the electrical grid. Finding efficiency of the PV-grid-connected system can be done by using a standard instrument which needs to disconnect the PV arrays from the grid before measurement. The measurement is also difficult and we lose energy during the measurement. This paper will present the system performance of a PV-grid-connected system installed in Thailand by using a monitoring system. The monitored data are installed by acquisition software into a computer. Analysis of monitored data will be done to find out the system performance without disconnecting the PV arrays from the system. The monitored data include solar radiation, PV voltage, PV current, and PV power which has been recorded from a 5 kWp system installed of amorphous silicon PV at Rajamangala University of Technology Suvarnabhumi, Nonthaburi, Thailand. The system performance of the system by using the data monitored is compared to the standard instrument measurement. The paper will give all details about system components, monitoring system, and monitored data. The result of data analysis will be fully given. (author)

  3. On-line monitoring system of PV array based on internet of things technology

    Science.gov (United States)

    Li, Y. F.; Lin, P. J.; Zhou, H. F.; Chen, Z. C.; Wu, L. J.; Cheng, S. Y.; Su, F. P.

    2017-11-01

    The Internet of Things (IoT) Technology is used to inspect photovoltaic (PV) array which can greatly improve the monitoring, performance and maintenance of the PV array. In order to efficiently realize the remote monitoring of PV operating environment, an on-line monitoring system of PV array based on IoT is designed in this paper. The system includes data acquisition, data gateway and PV monitoring centre (PVMC) website. Firstly, the DSP-TMS320F28335 is applied to collect indicators of PV array using sensors, then the data are transmitted to data gateway through ZigBee network. Secondly, the data gateway receives the data from data acquisition part, obtains geographic information via GPS module, and captures the scenes around PV array via USB camera, then uploads them to PVMC website. Finally, the PVMC website based on Laravel framework receives all data from data gateway and displays them with abundant charts. Moreover, a fault diagnosis approach for PV array based on Extreme Learning Machine (ELM) is applied in PVMC. Once fault occurs, a user alert can be sent via E-mail. The designed system enables users to browse the operating conditions of PV array on PVMC website, including electrical, environmental parameters and video. Experimental results show that the presented monitoring system can efficiently real-time monitor the PV array, and the fault diagnosis approach reaches a high accuracy of 97.5%.

  4. Design and Implementation of an Innovative Residential PV System

    Science.gov (United States)

    Najm, Elie Michel

    This work focuses on the design and implementation of an innovative residential PV system. In chapter one, after an introduction related to the rapid growth of solar systems' installations, the most commonly used state of the art solar power electronics' configurations are discussed, which leads to introducing the proposed DC/DC parallel configuration. The advantages and disadvantages of each of the power electronics' configurations are deliberated. The scope of work in the power electronics is defined in this chapter to be related to the panel side DC/DC converter. System integration and mechanical proposals are also within the scope of work and are discussed in later chapters. Operation principle of a novel low cost PV converter is proposed in chapter 2. The proposal is based on an innovative, simplified analog implementation of a master/slave methodology resulting in an efficient, soft-switched interleaved variable frequency flybacks, operating in the boundary conduction mode (BCM). The scheme concept and circuit configuration, operation principle and theoretical waveforms, design equations, and design considerations are presented. Furthermore, design examples are also given, illustrating the significance of the newly derived frequency equation for flybacks operating in BCM. In chapters 3, 4, and 5, the design implementation and optimization of the novel DC/DC converter illustrated in chapter 2 are discussed. In chapter 3, a detailed variable frequency BCM flyback design model leading to optimizing the component selections and transformer design, detailed in chapter 4, is presented. Furthermore, in chapter 4, the method enabling the use of lower voltage rating switching devices is also discussed. In chapter 5, circuitry related to Start-UP, drive for the main switching devices, zero-voltage-switching (ZVS) as well as turn OFF soft switching and interleaving control are fully detailed. The experimental results of the proposed DC/DC converter are presented in

  5. Simulation of a stand-alone renewable hydrogen system for residential supply

    Directory of Open Access Journals (Sweden)

    Martín Hervello

    2014-01-01

    Full Text Available La simulación por ordenador es un primer paso lógico previo a la realización de un proyecto de una construcción física además de ser una herramienta para el diseño de redes de energía. Los sistemas combinados son una solución para mejorar la disponibilidad de la energía suministrada con medios renovables. El principal inconveniente de las fuentes de energías renovables es su naturaleza altamente estacional, con grandes variaciones en el tiempo que pueden impedir el uso como base de consumo y limitar las horas de máxima demanda. El objetivo de este trabajo es realizar simulaciones para comprobar la autosuficiencia energética de una vivienda unifamiliar en base a energías renovables (eólica, solar-fotovoltaica utilizando como medio de almacenamiento un sistema híbrido de baterías e hidrógeno. Para ello se ha utilizado el programa Simulink®-Matlab® teniendo en cuenta los datos meteorológicos proporcionados por METEO-Galicia. El modelo puede ser aplicado para determinar la viabilidad de implementar una red energética en regiones específicas, y predecir el flujo de energía y el comportamiento del sistema durante todo el año.

  6. Microprocessor controlled limitation system for a stand-alone freely movable treatment couch

    NARCIS (Netherlands)

    van de Vondel, I.; Coppens, L.; Verellen, D.; Bel, A.; Linthout, N.; de Beukeleer, M.; van den Berge, D.; Storme, G.

    1998-01-01

    Because of the capability of free movement in the treatment room, we recently introduced a Hercules treatment couch on one of our linear accelerators. One of the advantages of this couch is that it allows for a more flexible way of patient setup and that it can be moved entirely out of the way to

  7. Optimal Sizing and Operation of Stand-Alone Hybrid Power Systems

    DEFF Research Database (Denmark)

    Kyriakidis, Ioannis; Chaudhary, Sanjay; Pillai, Jayakrishnan Radhakrishna

    2014-01-01

    The main goal of this study is to contribute to the design of an optimized hybrid renewable power plant for the island of Agios Efstratios. The initial step is to analyze the attributes and applications of various energy generation and storage technologies and focus on the most suitable ones for ...

  8. Analysis and optimization of hybrid excitation permanent magnet synchronous generator for stand-alone power system

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Huijun, E-mail: huijun024@gmail.com [School of Instrumentation Science and Opto-electronics Engineering, Beihang University (China); Qu, Zheng; Tang, Shaofei; Pang, Mingqi [School of Instrumentation Science and Opto-electronics Engineering, Beihang University (China); Zhang, Mingju [Shanghai Aerospace Control Technology Institute, Shanghai (China)

    2017-08-15

    Highlights: • One novel permanent magnet generator structure has been proposed to reduce voltage regulation ratio. • Finite element method and equivalent circuit methods are both employed to realize rapid generator design. • Design of experiment (DOE) method is used to optimize permanent magnet shape for reduce voltage waveform distortion. • The obtained analysis and experiment results verify the proposed design methods. - Abstract: In this paper, electromagnetic design and permanent magnet shape optimization for permanent magnet synchronous generator with hybrid excitation are investigated. Based on generator structure and principle, design outline is presented for obtaining high efficiency and low voltage fluctuation. In order to realize rapid design, equivalent magnetic circuits for permanent magnet and iron poles are developed. At the same time, finite element analysis is employed. Furthermore, by means of design of experiment (DOE) method, permanent magnet is optimized to reduce voltage waveform distortion. Finally, the validity of proposed design methods is validated by the analytical and experimental results.

  9. Stand-Alone Personalized Normative Feedback for College Student Drinkers: A Meta-Analytic Review, 2004 to 2014.

    Directory of Open Access Journals (Sweden)

    Keri B Dotson

    Full Text Available Norms clarification has been identified as an effective component of college student drinking interventions, prompting research on norms clarification as a single-component intervention known as Personalized Normative Feedback (PNF. Previous reviews have examined PNF in combination with other components but not as a stand-alone intervention.To investigate the degree to which computer-delivered stand-alone personalized normative feedback interventions reduce alcohol consumption and alcohol-related harms among college students and to compare gender-neutral and gender-specific PNF.Electronic databases were searched systematically through November 2014. Reference lists were reviewed manually and forward and backward searches were conducted.Outcome studies that compared computer-delivered, stand-alone PNF intervention with an assessment only, attention-matched, or active treatment control and reported alcohol use and harms among college students.Between-group effect sizes were calculated as the standardized mean difference in change scores between treatment and control groups divided by pooled standard deviation. Within-group effect sizes were calculated as the raw mean difference between baseline and follow-up divided by pooled within-groups standard deviation.Eight studies (13 interventions with a total of 2,050 participants were included. Compared to control participants, students who received gender-neutral (dbetween = 0.291, 95% CI [0.159, 0.423] and gender-specific PNF (dbetween = 0.284, 95% CI [0.117, 0.451] reported greater reductions in drinking from baseline to follow-up. Students who received gender-neutral PNF reported 3.027 (95% CI [2.171, 3.882] fewer drinks per week at first follow-up and gender-specific PNF reported 3.089 (95% CI [0.992, 5.186] fewer drinks. Intervention effects were small for harms (dbetween = 0.157, 95% CI [0.037, 0.278].Computer-delivered PNF is an effective stand-alone approach for reducing college student

  10. Stand-Alone Personalized Normative Feedback for College Student Drinkers: A Meta-Analytic Review, 2004 to 2014.

    Science.gov (United States)

    Dotson, Keri B; Dunn, Michael E; Bowers, Clint A

    2015-01-01

    Norms clarification has been identified as an effective component of college student drinking interventions, prompting research on norms clarification as a single-component intervention known as Personalized Normative Feedback (PNF). Previous reviews have examined PNF in combination with other components but not as a stand-alone intervention. To investigate the degree to which computer-delivered stand-alone personalized normative feedback interventions reduce alcohol consumption and alcohol-related harms among college students and to compare gender-neutral and gender-specific PNF. Electronic databases were searched systematically through November 2014. Reference lists were reviewed manually and forward and backward searches were conducted. Outcome studies that compared computer-delivered, stand-alone PNF intervention with an assessment only, attention-matched, or active treatment control and reported alcohol use and harms among college students. Between-group effect sizes were calculated as the standardized mean difference in change scores between treatment and control groups divided by pooled standard deviation. Within-group effect sizes were calculated as the raw mean difference between baseline and follow-up divided by pooled within-groups standard deviation. Eight studies (13 interventions) with a total of 2,050 participants were included. Compared to control participants, students who received gender-neutral (dbetween = 0.291, 95% CI [0.159, 0.423]) and gender-specific PNF (dbetween = 0.284, 95% CI [0.117, 0.451]) reported greater reductions in drinking from baseline to follow-up. Students who received gender-neutral PNF reported 3.027 (95% CI [2.171, 3.882]) fewer drinks per week at first follow-up and gender-specific PNF reported 3.089 (95% CI [0.992, 5.186]) fewer drinks. Intervention effects were small for harms (dbetween = 0.157, 95% CI [0.037, 0.278]). Computer-delivered PNF is an effective stand-alone approach for reducing college student drinking and

  11. Distributed Solar PV for Electricity System Resiliency: Policy and Regulatory Considerations (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    2014-11-01

    Distributed Solar PV systems have the potential of increasing the grid's resiliency to unforeseen events, such as extreme weather events and attacks. This paper presents the role that distributed PV can play in electric grid resiliency, introduces basic system design requirements and options, and discusses the regulatory and policy options for supporting the use of distributed PV for the purpose of increased electricity resiliency.

  12. Modeling of PV Systems Based on Inflection Points Technique Considering Reverse Mode

    Directory of Open Access Journals (Sweden)

    Bonie J. Restrepo-Cuestas

    2013-11-01

    Full Text Available This paper proposes a methodology for photovoltaic (PV systems modeling, considering their behavior in both direct and reverse operating mode and considering mismatching conditions. The proposed methodology is based on the inflection points technique with a linear approximation to model the bypass diode and a simplified PV model. The proposed mathematical model allows to evaluate the energetic performance of a PV system, exhibiting short simulation times in large PV systems. In addition, this methodology allows to estimate the condition of the modules affected by the partial shading since it is possible to know the power dissipated due to its operation at the second quadrant.

  13. PV-wind hybrid system performance. A new approach and a case study

    Energy Technology Data Exchange (ETDEWEB)

    Arribas, Luis; Cano, Luis; Cruz, Ignacio [Departamento de Energias Renovables, CIEMAT, Avda. Complutense 22, 28040 Madrid (Spain); Mata, Montserrat; Llobet, Ermen [Ecotecnia, Roc Boronat 78, 08005 Barcelona (Spain)

    2010-01-15

    Until now, there is no internationally accepted guideline for the measurement, data exchange and analysis of PV-Wind Hybrid Systems. As there is a need for such a tool, so as to overcome the barrier that the lack of confidence due to the absence of reliability means for the development of the market of Hybrid Systems, an effort has been made to suggest one tool for PV-Wind Hybrid Systems. The suggested guidelines presented in this work are based on the existing guidelines for PV Systems, as a PV-Wind Hybrid system can be roughly thought of as a PV System to which wind generation has been added. So, the guidelines for PV Systems are valid for the PV-Wind System, and only the part referred to wind generation should be included. This has been the process followed in this work. The proposed method is applied to a case study, the CICLOPS Project, a 5 kW PV, 7.5 kW Wind Hybrid system installed at the Isolated Wind Systems Test Site that CIEMAT owns in CEDER (Soria, Spain). This system has been fully monitored through a year and the results of the monitoring activity, characterizing the long-term performance of the system are shown in this work. (author)

  14. Dynamic response evaluation of sensorless MPPT method for hybrid PV-DFIG wind turbine system

    Directory of Open Access Journals (Sweden)

    Danvu Nguyen

    2016-01-01

    Full Text Available This research proposes a sensorless Maximum Power Point Tracking (MPPT method for a hybrid Photovoltaic-Wind system, which consists of Photovoltaic (PV system and Doubly-Fed Induction Generator (DFIG Wind Turbine. In the hybrid system, the DC/DC converter output of the PV system is directly connected to the DC-link of DFIG’s back-to-back converter. Therefore, the PV inverter and its associated circuit can be removed in this structure. Typically, the PV power is monitored by using PV current sensor and PV voltage sensor for MPPT. In this paper, the powers of converters on grid side and rotor side of DFIG are used to estimate the PV power without the PV current sensor. That can efficiently reduce the cost of the hybrid system. The detailed analysis of the sensorless MPPT method, which includes derived equations and operation response, is also presented in this paper. In addition, an overview of PV-DFIG research in literature is stated to supply comprehensive knowledge of related research.

  15. Installation of solar PV systems in Sri Lanka

    Energy Technology Data Exchange (ETDEWEB)

    Fernando, M.P.T.P. [Sarvodaya Rural Technical Services, Moratuwa (Sri Lanka)

    1995-10-01

    The tropical country of Sri Lanka has hydroelectric power plants sufficient to provide electricity to only 40% of its 25,000 villages. The electric power needs of the average Sri Lankan rural communities are basic: three or four lights to illuminate their house and a power supply for their televisions. Solar radiation is abundant throughout the year. To take advantage of this resource, the Sarvodaya Rural Technical Services launched a Solar PV pilot demonstration project in the rural areas not served by the electric grid. The systems were being installed on an individual residence basis and funded by loans. Social and cultural problems which have arisen during the course of the project have slowed its implementation. This study identifies the problems and makes recommendations to resolve the current problems and avoid new ones.

  16. Field Demonstration of Using Advanced PV Inverter Functionality to Mitigate the Impacts of High-Penetration PV Grid Integration on the Distribution System

    Energy Technology Data Exchange (ETDEWEB)

    Mather, Barry; Gebeyehu, Araya

    2015-06-14

    This paper describes a field demonstration that was completed to show the ability of currently installed PV inverters to implement advanced PV inverter functionality and that such functionality was effective at reducing the voltage-related PV impacts of high-penetration PV integration. A distribution circuit was instrumented and then tested for a two week period using off-unity power factor operation. Specifically, an inductive power factor of -0.95 was demonstrated. The results show that the PV inverters were capable of such operation and that the use of off-unity power factor operation was highly effective at reducing the voltage-related impacts of the PV systems interconnected to the circuits used in the demonstration. The impacts of using off-unity power factor operation - resulting in additional reactive current flow on the distribution circuit - are also presented and analyzed.

  17. Fire risk related to the use of PV systems in building facades

    Directory of Open Access Journals (Sweden)

    Mazziotti Lamberto

    2016-01-01

    Full Text Available Nowadays the use of photovoltaic (PV systems in buildings is not only related to the solar energy conversion into electrical one, but these PV modules or panels could also be used with aesthetic features or, even more, as thermal protection systems in building facades. Thanks to the technical development of the photovoltaic industry, PV system can easily be architectonically integrated into building construction elements such as roofs, vertical façade components, both with opaque or transparent surfaces. Furthermore, PV construction facades elements could also be provided by openings like doors or windows. Accident analysis show that the use of PV systems as construction elements could increase the risk of fire in buildings. In fact, international and National data report a growing number of fire caused by PV system applied or integrated in buildings. The Italian National Fire Service, that is the Authority having jurisdiction for fire safety in buildings (in Italy, in 2012 has released a Guideline in order to asses and mitigate the risk of fire when a PV system is put in place on a building as a façade or as a roof. The Guideline addresses not only the reduction of the PV fire ignitions causes and the aspects related to the fire spread due to the combustible parts that constitute PV modules or panels, but also take into account the safety of both the maintenance personnel and the rescue teams. This paper focuses on the fire safety aspects related to the use of fire PV panels and systems in building facades, showing some interesting experimental data related to the fire behaviour of these components and underlining the factors that promote the spread of fire, like the high operating temperature of the PV system itself.

  18. Use of stand-alone anchored intervertebral cage in the surgical treatment of patients with symptomatic cervical spondylosis

    Directory of Open Access Journals (Sweden)

    Tilen Žele

    2015-03-01

    Full Text Available Background:One of the most common surgical operations for treatment of cervical spondylosis is anterior cervical discectomy with fusion (ACDF. In order to achieve stable fusion after discectomy and avoid dysphagia the artificial stand-alone zero-profile cages with integrated screws were developed and introduced into clinical practice. Outcome and complications after ACDF with such cages were not adequately assessed yet.Methods:We analyzed 20 consecutive patients with cervical spondylosis treated in our institution with ACDF with stand-alone zero-profile cage Zero-P. Before and after surgery and then 6, 12 and 24 months after surgery we assessed the level of pain with VAS scale, severity of myelopathy with mJOA scale and dysphagia with four level scale. Treatment outcome was assessed after 2 years according to Odom's criteria.Results:No complications occurred during surgery or recovery after surgery. The VAS score after surgery and then after 6, 12 and 24 months was statistically significantly lower than before surgery (p<0.05. The mJOA scores were 6, 12 and 24 months after surgery statistically significantly higher than before surgery (p<0.05. Transient and mild dysphagia was present after surgery in 15% (3/20 of patients and 6, 12 or 24 months after surgery in none. Outcome after 2 years was excellent in 9 patients and good in 11 patients.Conclusions:Operative treatment of symptomatic cervical spondylosis with ACDF using stand-alone zero-profile cage with integrated screws is safe and efficient. Incidence of dysphagia after surgery is low and generally transient.

  19. Wide-band gap devices in PV systems - opportunities and challenges

    DEFF Research Database (Denmark)

    Sintamarean, Nicolae Cristian; Eni, Emanuel-Petre; Blaabjerg, Frede

    2014-01-01

    have an important role in the cost reduction. To increase the efficiency of PV systems, most of solutions for PV inverters have moved to three-level (3L) structures reaching typical efficiencies of 98% due to low switching losses of 600V Si IGBT or MOSFET and reduced core losses in the filter......The recent developments in wide band-gap devices based GaN and SiC is showing a high impact on the PV-inverter technology, which is strongly influenced by efficiency, power density and cost. Besides the high efficiency of PV inverters, also the mechanical size, the compactness and simple structure......) three-phase PV-inverter topologies in terms of efficiency, thermal loading distribution and costs. Moreover the above mentioned PV-inverters are built and tested in laboratory in order to validate the obtained results....

  20. Distributed measurement system for long term monitoring of clouding effects on large PV plants

    DEFF Research Database (Denmark)

    Paasch, K. M.; Nymand, M.; Haase, F.

    2013-01-01

    A recording system for the generation of current-voltage characteristics of solar panels is presented. The system is intended for large area PV power plants. The recorded curves are used to optimize the energy output of PV power plants, which are likely to be influenced by passing clouds...

  1. Evaluation of irradiation measurements on tilted planes at PV systems in the Netherlands

    NARCIS (Netherlands)

    Betcke, J.W.H.; Dijk, V.A.P. van; Ramaekers, L.A.M.; Zolingen, R.J.C. van

    1998-01-01

    Monitoring data of Dutch PV systems in the field show lower values for the measured global irradiation in the array plane than expected from model calculatations. Since the locations of the PV systems contain obstacles, we expect that shielding of diffuse irradiation may cause the difference. For

  2. PV-hybrid and mini-grid

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    photovoltaic - fuel cell - direct storage - power supply units; (11) Djungle power - A more remote AC bus; (12) Quality control tools applied to a PV micro-grid in Ecuador; (13) Integral Evaluation of energy supply systems at Mountain Refuges; (14) Hyress project: Study case of Tunisia. Installation, set-up and first results; (15) PV hybrid systems on Mountain Huts: The experience with the project CAI ENERGIA 2000; (16) Process management in zero-emission communities: Adaptation of consumption and production; (17) TRNSYS simulation of a system consisted of PV panels and H{sub 2} production and storage to feed a Remote Telecom Application (HildrosolarH2); (18) Photovoltaic forecasting: A state of the art; (19) PV*SOL 5.0 standalone - Simulation of a stand-alone AC system; (20) Effect of wind speed and solar irradiation on the optimization of a PV wind battery system to supply a Telecommunications station; (21) Polysun: PV, wind and power-heat cogeneration in one design tool; (22) Comparative study between distributed and centralised PV generation in Island power systems under variable weather conditions; (23) Development of a test facility for PV-wind hybrid energy systems; (24) Evaluation of a micro PV-wind hybrid system in Nordic climate conditions; (25) Prismes: The INES micro-grid platform; (26) Estimation of statistical electric energy demand profiles of non electrified regions in Northern Brazil.

  3. Losses Evaluation for a Two-Level Three-Phase Stand-Alone Voltage Source Converter Using Model Predictive Control

    DEFF Research Database (Denmark)

    Al hasheem, Mohamed; Dragicevic, Tomislav; Rivera, Marco

    2017-01-01

    conventional and improved controller is conducted in terms of losses. The switching and conduction losses for the VSC are calculated using MATLAB/SIMULINK and PLECS software. A power level up to 1 kW is considered for the conventional and the improved schemes. All simulation and experimental results......This paper discusses a Model Predictive Control (MPC) scheme for a Voltage Source Converter (VSC) where the aim is to minimize losses and Total Harmonics distortion (THD) compared to the conventional MPC scheme. Different Cost Functions (CFs) are applied to the stand-alone VSC. A comparison between...

  4. Performance monitoring of different module technologies and design configurations of PV system in South Africa

    CSIR Research Space (South Africa)

    Roro, Kittessa T

    2016-06-01

    Full Text Available Performance monitoring of different module technologies and design configurations of PV system in South Africa Presentation at the EU PVSEC 2016 Munich, 22 June 2016 Dr Kittessa Roro Cell: +27 825495131 Email: KRoro@csir.co.za 1 Agenda Polycrystalline... Procurement Programme (REIPPPP) 5 At present, more than 1 000 MW of PV are operational in South Africa Pipeline of PV projects in the REIPPPP for large, utility-scale PV 398 417 626 2 291 435 415 Operational 1 043 Under construction Awaiting...

  5. Assessment of MPPT Techniques During the Faulty Conditions of PV System

    Directory of Open Access Journals (Sweden)

    Bhukya Krishna Naick

    2018-01-01

    Full Text Available The contribution of Distributed Generation (DG systems like wind energy systems and solar Photovoltaic (PV systems on the generation of electricity has increased. Out of these DG systems, the PV systems have gained wide popularity, because of the availability of solar energy throughout the day. Depending on the size of PV installations, a large number of PV modules can be interconnected in the form of series and parallel connection. Since a large number of modules are interconnected, it is possible for the faults in a PV array to occur due to the failure of protection system, which can cause damage to the PV module and also the decrease in the output power. This paper presents the tracking of a maximum power point under the faulty conditions of 12x5 PV array. The fault conditions that have been considered in the PV array are open circuit fault, line to ground, line to line and failure of bypass diodes. Perturb and observe, incremental conductance and fuzzy logic controller are the maximum power point tracking techniques that have been implemented. For each of the fault conditions, the results have been presented in terms of the maximum power tracked, tracking time and tracking efficiency.

  6. Establishment of key grid-connected performance index system for integrated PV-ES system

    Science.gov (United States)

    Li, Q.; Yuan, X. D.; Qi, Q.; Liu, H. M.

    2016-08-01

    In order to further promote integrated optimization operation of distributed new energy/ energy storage/ active load, this paper studies the integrated photovoltaic-energy storage (PV-ES) system which is connected with the distribution network, and analyzes typical structure and configuration selection for integrated PV-ES generation system. By combining practical grid- connected characteristics requirements and technology standard specification of photovoltaic generation system, this paper takes full account of energy storage system, and then proposes several new grid-connected performance indexes such as paralleled current sharing characteristic, parallel response consistency, adjusting characteristic, virtual moment of inertia characteristic, on- grid/off-grid switch characteristic, and so on. A comprehensive and feasible grid-connected performance index system is then established to support grid-connected performance testing on integrated PV-ES system.

  7. SedInConnect: a stand-alone, free and open source tool for the assessment of sediment connectivity

    Science.gov (United States)

    Crema, Stefano; Cavalli, Marco

    2018-02-01

    There is a growing call, within the scientific community, for solid theoretic frameworks and usable indices/models to assess sediment connectivity. Connectivity plays a significant role in characterizing structural properties of the landscape and, when considered in combination with forcing processes (e.g., rainfall-runoff modelling), can represent a valuable analysis for an improved landscape management. In this work, the authors present the development and application of SedInConnect: a free, open source and stand-alone application for the computation of the Index of Connectivity (IC), as expressed in Cavalli et al. (2013) with the addition of specific innovative features. The tool is intended to have a wide variety of users, both from the scientific community and from the authorities involved in the environmental planning. Thanks to its open source nature, the tool can be adapted and/or integrated according to the users' requirements. Furthermore, presenting an easy-to-use interface and being a stand-alone application, the tool can help management experts in the quantitative assessment of sediment connectivity in the context of hazard and risk assessment. An application to a sample dataset and an overview on up-to-date applications of the approach and of the tool shows the development potential of such analyses. The modelled connectivity, in fact, appears suitable not only to characterize sediment dynamics at the catchment scale but also to integrate prediction models and as a tool for helping geomorphological interpretation.

  8. The performance of a combined solar photovoltaic (PV) and thermoelectric generator (TEG) system

    DEFF Research Database (Denmark)

    Bjørk, Rasmus; Nielsen, Kaspar Kirstein

    2015-01-01

    The performance of a combined solar photovoltaic (PV) and thermoelectric generator (TEG) system is examined using an analytical model for four different types of commercial PVs and a commercial bismuth telluride TEG. The TEG is applied directly on the back of the PV, so that the two devices have...

  9. Leakage Current Elimination of Four-Leg Inverter for Transformerless Three-Phase PV Systems

    DEFF Research Database (Denmark)

    Guo, Xiaoqiang; He, Ran; Jian, Jiamin

    2016-01-01

    Eliminating the leakage current is one of the most important issues for transformerless three phase photovoltaic (PV) systems. In this paper, the leakage current elimination of a three-phase four-leg PV inverter is investigated. With the common mode loop model established, the generation mechanism...

  10. Study on Soft Phase Locked Method to Solving the Synchronization Problem of Active Power Filter in Stand-alone Power Grid

    DEFF Research Database (Denmark)

    Zhuo, Fang; Wu, Longhui; Chen, Zhe

    2009-01-01

    on zero-cross detection can't work effectively in small rating stand-alone power grid. Then a soft phase locked loop with additional filter is proposed. It can lock the phase angle on to the positive sequence of fundamental voltage accurately and rapidly. It ensures the performance of APF applied...... in the small rating stand-alone power grid. Moreover, the soft phase locked loop is easy to be implemented in a Digital Signal Processor (DSP). Simulation and experimental results validate that the soft phase locked loop has satisfactory performance.......Traditional LC filters can't work stably in small rating stand-alone power grid. So active power filter (APF) is becoming an important tool to solve the power quality problem in small rating stand-alone power grid. In most current detection algorithm of APF, it needs a synchronizing signal. Firstly...

  11. Overview of PV Wind hybrid system activities in Germany

    Energy Technology Data Exchange (ETDEWEB)

    Bopp, G.; Gabler, H.; Kiefer, K.; Preiser, K.; Wiemken, E. [Fraunhofer Institute for Solar Energy Systems ISE, Freiburg (Germany)

    1997-12-31

    Photovoltaic solar generators combined with diesel engines, in some cases additionally with wind energy converters, and battery energy storage are powering isolated mountain lodges, information centers in nature parks, isolated farms or dwellings all over Europe. A total of 300,000 buildings in Europe are estimated to be not connected to the public grid. This represents a major market potential for photovoltaic, as often photovoltaic power generation is less expensive than a connection to the electric utility. The Fraunhofer Institute for Solar Energy Systems ISE has planned, realized and monitored about 30 hybrid remote energy supply systems with PV generators typically around 5 kW for loads typically around 20 kWh per day. More than one hundred years of operational experience accumulated so far, are a sound foundation on which to draw an interim balance over problems solved and technical questions still under development. Room for further technical development is seen in the domain of system reliability and the reduction of operating costs as well as in the optimization of the utilization of the electric energy produced by the PV generator. [Espanol] Para la electrificacion en toda Europa de casas de campo en la montana, centros de informacion, parques naturales, granjas aisladas o conjuntos habitacionales, se estan usando generadores fotovoltaicos combinados con maquinas diesel, en algunos casos adicionalmente con convertidores de energia del viento y baterias para el almacenamiento de energia. Se estima que en Europa un total de 300,000 edificios no estan conectados a la red publica. Esto representa un gran mercado potencial para los sistemas fotovoltaicos, ya que a menudo la generacion fotovoltaica es menos costosa que una conexion a la empresa electrica. El Instituto Fraunhofer para Sistemas de Energia Solar ISE ha planeado, llevado a cabo y monitoreado alrededor de 30 sistemas hibridos remotos de suministro de energia con generadores fotovoltaicos

  12. PV Diesel island systems remote from the network: modelling and simulation; Netzferne PV-Diesel-Inselsysteme: Modellierung und Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Dumbs, C. [Ecole des Mines de Paris, 06 - Sophia Antipolis (France). Centre d`Energetique]|[Ecole des Mines de Paris, 06 - Sophia Antipolis (France). Centre de Mathematiques Apliquees; Maizi, N. [Ecole des Mines de Paris, 06 - Sophia Antipolis (France). Centre de Mathematiques Apliquees; Neirac, F. [Ecole des Mines de Paris, 06 - Sophia Antipolis (France). Centre d`Energetique

    1998-12-01

    The simulation program for PV Diesel hybrid systems introduced here serves for the design and simulation of photo-voltaic electricity supply systems with storage batteries. It makes possible the detailed calculation of the currents and voltages between the system components and therefore the detailed accurate simulation of the method of operation of an island system. The use of a short step-width of simulation (1 to 10 minute average values) is the precondition for a detailed analysis of the individual components and their mutual collaboration in the overall system. The user has the possibility of fitting measuring instruments for monitoring the system variables at all junctions. By successive variation of certain parameters and repeated simulation, a simulation-supported optimisation of the design process can already be achieved today. [Deutsch] Das hier vorgestellte Simulationsprogramm fuer netzferne PV-Diesel Hybridsysteme dient der Auslegung und Simulation von Photovoltaik-Stromversorgungssystemen mit Batteriespeicher. Derzeit ermoeglicht es eine detaillierte Berechnung der Stroeme und Spannungen zwischen den Systemkomponenten und damit eine detailgenaue Simulation der Funktionsweise eines Inselsystems. Die Verwendung einer kurzen Simulationsschrittweite (1- bis 10-minuetige Mittelwerte) stellt die Voraussetzung fuer eine detaillierte Analyse der Einzelkomponenten sowie deren gegenseitiges Zusammenwirken im Gesamtsystem dar. Der Benutzer hat die Moeglichkeit, an allen Verbindungspunkten des Systems Messinstrumente zur Ueberwachung der Systemvariablen anzubringen. Durch sukzessives Variieren bestimmter Parameter und die wiederholte Simulation laesst sich damit schon heute eine simulationsgestuetzte Optimierung des Auslegungsprozesses erreichen. (orig./RHM)

  13. Annual analysis of heat pipe PV/T systems for domestic hot water and electricity production

    International Nuclear Information System (INIS)

    Pei Gang; Fu Huide; Ji Jie; Chow Tintai; Zhang Tao

    2012-01-01

    Highlights: ► A novel heat pipe photovoltaic/thermal system with freeze protection was proposed. ► A detailed annual simulation model for the HP-PV/T system was presented. ► Annual performance of HP-PV/T was predicted and analyzed under different condition. - Abstract: Heat-pipe photovoltaic/thermal (HP-PV/T) systems can simultaneously provide electrical and thermal energy. Compared with traditional water-type photovoltaic/thermal systems, HP-PV/T systems can be used in cold regions without being frozen with the aid of a carefully selected heat-pipe working fluid. The current research presents a detailed simulation model of the HP-PV/T system. Using this model, the annual electrical and thermal behavior of the HP-PV/T system used in three typical climate areas of China, namely, Hong Kong, Lhasa, and Beijing, are predicted and analyzed. Two HP-PV/T systems, with and without auxiliary heating equipment, are studied annually under four different kinds of hot-water load per unit collecting area (64.5, 77.4, 90.3, and 103.2 kg/m 2 ).

  14. Validation of PV-RPM Code in the System Advisor Model.

    Energy Technology Data Exchange (ETDEWEB)

    Klise, Geoffrey Taylor [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lavrova, Olga [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Freeman, Janine [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2017-04-01

    This paper describes efforts made by Sandia National Laboratories (SNL) and the National Renewable Energy Laboratory (NREL) to validate the SNL developed PV Reliability Performance Model (PV - RPM) algorithm as implemented in the NREL System Advisor Model (SAM). The PV - RPM model is a library of functions that estimates component failure and repair in a photovoltaic system over a desired simulation period. The failure and repair distributions in this paper are probabilistic representations of component failure and repair based on data collected by SNL for a PV power plant operating in Arizona. The validation effort focuses on whether the failure and repair dist ributions used in the SAM implementation result in estimated failures that match the expected failures developed in the proof - of - concept implementation. Results indicate that the SAM implementation of PV - RPM provides the same results as the proof - of - concep t implementation, indicating the algorithms were reproduced successfully.

  15. Economic Comparison of Two Business Models for Implementation of Small Integrated PV Systems

    International Nuclear Information System (INIS)

    Matak, N.; Krajacic, G.; Jerkic, E.; Duic, N.

    2016-01-01

    We compared two different models for the implementation of small photovoltaic solar systems in the Croatia. The new prosumer model presented in the new Croatian law on the Renewable Energy Sources and Highly Efficient Cogeneration (OG 100/15) and PV ESCO model which is similar to net metering. The PV ESCO model is developed from authors to determine possibility to raise payback period of small integrated PV systems. The comparison was done on a 15-minute basis and there were compared values of Simple Payback Period (SPP) for different locations and systems size considering electricity demand and market prices. Internal Rate of Return (IRR) and Net Present Value (NPV) were compared for 4 different cases. Conducted comparison showed that PV ESCO model is always more favourable for the owner of PV system in terms of lower SPP and higher IRR and NPV. It has been noticed that for systems higher than 5 kWp use of PV ESCO model is recommended. For smaller systems it is not always clear which model should be used, since some losses are generated in the system on the side of the electricity supply company. For smaller systems from 2 to 5 kWp, PV ESCO model has SPP from 7.5 to 13 years and SPP value for the prosumer model is 8.7 to 15 years. This difference is higher when comparing PV system from 6 to 10 kWp. SPP for PV ESCO model, in that case, is from 10 to 13 years and in the prosumer model is from 17.5 to 28 years.(author).

  16. A novel solar multifunctional PV/T/D system for green building roofs

    International Nuclear Information System (INIS)

    Feng, Chaoqing; Zheng, Hongfei; Wang, Rui; Yu, Xu; Su, Yuehong

    2015-01-01

    Highlights: • A novel transparent roof combines the solar PV/T/D system with green building design. • Novel photovoltaic-thermal roofing design can achieve excellent light control at noon. • The roof has no obvious influence on indoor light intensity in morning and afternoon. • Higher efficiency of solar energy utilization could be achieved with new roofing. - Abstract: A novel transparent roof which is made of solid CPC (Compound Parabolic Concentrator) PV/T/D (Photovoltaic/Thermal/Day lighting) system is presented. It combines the solar PV/T/D system with green building design. The PV/T/D system can achieve excellent light control at noon and adjust the thermal environment in the building, such that high efficiency utilization of solar energy could be achieved in modern architecture. This kind of roof can increase the visual comfort for building occupants; it can also avoid the building interior from overheating and dazzling at noon which is caused by direct sunlight through transparent roof. Optical simulation software is used to track the light path in different incidence angles. CFD (Computational Fluid Dynamics) simulation and steady state experiment have been taken to investigate the thermal characteristic of PV/T/D device. Finally, the PV/T/D experimental system was built; and the PV efficiency, light transmittance and air heating power of the system are tested under real sky conditions

  17. Advanced Inverter Technology for High Penetration Levels of PV Generation in Distribution Systems

    Energy Technology Data Exchange (ETDEWEB)

    Schauder, C.

    2014-03-01

    This subcontract report was completed under the auspices of the NREL/SCE High-Penetration Photovoltaic (PV) Integration Project, which is co-funded by the U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE) and the California Solar Initiative (CSI) Research, Development, Demonstration, and Deployment (RD&D) program funded by the California Public Utility Commission (CPUC) and managed by Itron. This project is focused on modeling, quantifying, and mitigating the impacts of large utility-scale PV systems (generally 1-5 MW in size) that are interconnected to the distribution system. This report discusses the concerns utilities have when interconnecting large PV systems that interconnect using PV inverters (a specific application of frequency converters). Additionally, a number of capabilities of PV inverters are described that could be implemented to mitigate the distribution system-level impacts of high-penetration PV integration. Finally, the main issues that need to be addressed to ease the interconnection of large PV systems to the distribution system are presented.

  18. A study of grid-connected photovoltaic (PV) system in Hong Kong

    International Nuclear Information System (INIS)

    Li, Danny H.W.; Cheung, K.L.; Lam, Tony N.T.; Chan, Wilco W.H.

    2012-01-01

    Photovoltaic (PV) is one of the promising solar energy applications. Measured data can give the realistic performance of PV systems under actual operating environments for product selection and system design. This paper studies a grid-connected PV system installed in an institutional building. Technical data including available solar radiation and output energy generated were systematically recorded and analyzed. The performance of the PV system is elaborated in terms of energy, environmental and financial aspects. Feed-in-tariff (FIT) schemes with high electricity selling price can encourage the deployment of PV system. The monetary payback period (MPBP) for the PV system was computed to be 72.4 years when the electricity buying price is equal to the electricity selling price. If carbon trading was considered, the payback was shortened to 61.4 years. The embodied energy payback period (EEPBP) was estimated to be 8.9 years. The findings would be useful for planning grid-connected PV installations and applicable to other spaces with similar architectural layouts.

  19. Clinical and radiological outcome after anterior cervical discectomy and fusion with stand-alone empty polyetheretherketone (PEEK) cages.

    Science.gov (United States)

    Shiban, Ehab; Gapon, Karina; Wostrack, Maria; Meyer, Bernhard; Lehmberg, Jens

    2016-02-01

    To evaluate long-term results after one-, two-, and three-level anterior cervical discectomy and fusion (ACDF) with stand-alone empty polyetheretherketone (PEEK) cages. We performed a retrospective review of a consecutive patient cohort that underwent ACDF with stand-alone empty PEEK cages between 2007 and 2010 with a minimum follow-up of 12 months. Radiographic follow-up included static and flexion/extension radiographs. Changes in the operated segments were measured and compared to radiographs directly after surgery. Clinical outcome was evaluated by a physical examination, pain visual analog scale (VAS), and health-related quality of life (HRQL) using the EuroQOL questionnaire (EQ-5D). Analysis of associations between fusion, subsidence, cervical alignment, and clinical outcome parameters were performed. Of 407 consecutive cases, 318 met all inclusion criteria. Follow-up data were obtained from 265 (83 %) cases. The mean age at presentation was 55 years and 139 patients were male (52 %). In the sample, 127, 125, and 13 patients had one-, two-, and three-level surgeries, respectively; 132 (49 %) presented with spondylotic cervical myelopathy and 133 (50 %) with cervical radiculopathy. Fusion was achieved in 85, 95, and 94 % of segments in one-, two-, and three-level surgeries, respectively. Non-fusion was associated with higher VAS pain levels. Radiographic adjacent segment disease (ASD) was observed in 20, 29, and 15 % in one-, two-, and three-level surgeries, respectively. ASD was associated with lower HRQL. Subsidence was observed in 25, 27, and 15 % of segments in one-, two-, and three-level surgeries, respectively. However, this had no influence on clinical outcome. Follow-up operations for symptomatic adjacent disc disease and implant failure at index level were needed in 16 (6 %) and four (1.5 %) cases, respectively. Younger age was associated with better clinical outcome. Multilevel surgery favored better myelopathy outcomes and fusion reduced overall

  20. Innovative Ballasted Flat Roof Solar PV Racking System

    Energy Technology Data Exchange (ETDEWEB)

    Peek, Richard T. [Cascade Engineering, Grand Rapids, MI (United States)

    2014-12-15

    The objective of this project was to reduce the cost of racking for PV solar on flat commercial rooftops. Cost reductions would come from both labor savings and material savings related to the installation process. The rack would need to accommodate the majority of modules available on the market. Cascade Engineering has a long history of converting traditional metal type applications over to plastic. Injection molding of plastics have numerous advantages including selection of resin for the application, placing the material exactly where it is needed, designing in features that will speed up the installation process, and weight reduction of the array. A plastic rack would need to meet the requirements of UL2703, Mounting systems, mounting devices, clamping/retention devices, and ground lugs for use with flat-plate photovoltaic modules and panels. Comparing original data to the end of project racking design, racking material costs were reduced 50% and labor costs reduced 64%. The racking product accommodates all 60 and 72 cell panels on the market, meets UL2703 requirements, contributes only 1.3 pounds per square foot of weight to the array, requires little ballast to secure the array, automatically grounds the module when the module is secured, stacks/nests well for shipping/fewer lifts to the roof, provides integrated wire routing, allows water to drain on the roof, and accommodates various seismic roof connections. Project goals were achieved as noted in the original funding application.

  1. Review of stand-alone photovoltaic application projects sponsored by US DOE and US AID

    Science.gov (United States)

    Bifano, W. J.

    Experience with dc photovoltaic systems (without backup power) and ranging in output from 23 to 3,500 peak watts, in a wide range of environmental conditions and with a wide range of insolation, is described. Cooperation of NASA with other government agencies resulted in the installation of an air pollution monitor in New Jersey, a seismic sensor in Hawaii, power for lookout towers in national forests in California, an electric power system for a Papago Indian village in Arizona, and a power system for a grain mill and water pump in Tangaye, Upper Volta. Significant operational results are discussed and system reliability is assessed for the 20 experimental systems installed since 1976. Additional systems to be installed overseas are highlighted, and economic factors are considered.

  2. Effects of frame shadow on the PV character of a photovoltaic/thermal system

    International Nuclear Information System (INIS)

    Wang, Yunyun; Pei, Gang; Zhang, Longcan

    2014-01-01

    Highlights: • We proposed a method for predicting the performance of a partly shaded PV cell. • Even a small shadow can significantly affect the performance of a PV/T system. • A parallel circuit is better than a series circuit in addressing partial shadows. • The total output of a series circuit within a day/year is higher than that of a parallel circuit. - Abstract: Most photovoltaic/thermal (PV/T) systems have an air layer between the glass cover and the cells to minimize heat loss and to improve overall efficiency. This feature is not found in typical PV systems. The frame border that supports the glass cover casts a shadow over the cells near the frame when sunlight is slanted. This design is common in PV/T systems. The objective of this study is to determine the effects of a frame shadow on PV/T systems. A mathematical model of a PV module in a PV/T system is established. An experimental research on a partly shaded single cell is then conducted. Based on the module model and the results of the experiment, a single cell model that simulates the performance of partly shaded cells is developed and integrated into an existing system model. The new model can be applied to simulate frame shadow in a PV/T system. Results show that the performance of a partly shaded single cell can be calculated as the cell operates below the average irradiation intensity of the shaded and unshaded parts. In the worst-case scenario, the frame shadow can cause a 39.3% decrease in photoelectric efficiency. Although the parallel circuit performs better than the series circuit in minimizing loss caused by the frame shadow, the latter has a higher total output

  3. Quantification, challenges and outlook of PV integration in the power system: a review by the European PV Technology Platform

    DEFF Research Database (Denmark)

    Alet, Pierre-Jean; Baccaro, Federica; De Felice, Matteo

    2015-01-01

    Integration in the power system has become a limiting factor to the further development of photovoltaics. Proper quantification is needed to evaluate both issues and solutions; the share of annual electricity demand is widely used but we found that some of the metrics which are related to power...... networks. Forecasting, storage, and combination with other renewable sources are interdependent solutions to solve the intermittency issue. Finally, we found that PV is also an opportunity to reduce some investment required to upgrade existing power networks. Through integration with micro-grids and hybrid...

  4. Interconnecting PV on New York City's Secondary Network Distribution System

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, K; Coddington, M; Burman, K; Hayter, S; Kroposki, B; Watson, and A

    2009-11-01

    The U.S. Department of Energy (DOE) has teamed with cities across the country through the Solar America Cities (SAC) partnership program to help reduce barriers and accelerate implementation of solar energy. The New York City SAC team is a partnership between the City University of New York (CUNY), the New York City Mayor s Office of Long-term Planning and Sustainability, and the New York City Economic Development Corporation (NYCEDC).The New York City SAC team is working with DOE s National Renewable Energy Laboratory (NREL) and Con Edison, the local utility, to develop a roadmap for photovoltaic (PV) installations in the five boroughs. The city set a goal to increase its installed PV capacity from1.1 MW in 2005 to 8.1 MW by 2015 (the maximum allowed in 2005). A key barrier to reaching this goal, however, is the complexity of the interconnection process with the local utility. Unique challenges are associated with connecting distributed PV systems to secondary network distribution systems (simplified to networks in this report). Although most areas of the country use simpler radial distribution systems to distribute electricity, larger metropolitan areas like New York City typically use networks to increase reliability in large load centers. Unlike the radial distribution system, where each customer receives power through a single line, a network uses a grid of interconnected lines to deliver power to each customer through several parallel circuits and sources. This redundancy improves reliability, but it also requires more complicated coordination and protection schemes that can be disrupted by energy exported from distributed PV systems. Currently, Con Edison studies each potential PV system in New York City to evaluate the system s impact on the network, but this is time consuming for utility engineers and may delay the customer s project or add cost for larger installations. City leaders would like to streamline this process to facilitate faster, simpler, and

  5. A grid-tied PV system for commercial load and peak load reduction: South African case study

    CSIR Research Space (South Africa)

    Senatla, Mamahloko

    2017-08-01

    Full Text Available Photovoltaic (PV) systems are increasingly being installed globally for various reasons including reducing the carbon footprint, improving energy access, for supply and demand side management purposes. The price of PV has been going down in recent...

  6. Mathematical modeling of photovoltaic thermal PV/T system with v-groove collector

    Science.gov (United States)

    Zohri, M.; Fudholi, A.; Ruslan, M. H.; Sopian, K.

    2017-07-01

    The use of v-groove in solar collector has a higher thermal efficiency in references. Dropping the working heat of photovoltaic panel was able to raise the electrical efficiency performance. Electrical and thermal efficiency were produced by photovoltaic thermal (PV/T) system concurrently. Mathematical modeling based on steady-state thermal analysis of PV/T system with v-groove was conducted. With matrix inversion method, the energy balance equations are explained by means of the investigative method. The comparison results show that in the PV/T system with the V-groove collector is higher temperature, thermal and electrical efficiency than other collectors.

  7. Simplified life-cycle analysis of PV systems in buildings: present situation and future trends

    International Nuclear Information System (INIS)

    Frankl, P.; Masini, A.; Gamberale, M.; Toccaceli, D.

    1998-01-01

    The integration of photovoltaic (PV) systems in buildings shows several advantages compared to conventional PV power plants. The main objectives of the present study are the quantitative evaluation of the benefits of building-integrated PV systems over their entire life-cycle and the identification of best solutions to maximise their energy efficiency and CO 2 mitigation potential. In order to achieve these objectives, a simplified life-cycle analysis (LCA) has been carried out. Firstly, a number of existing applications have been studied. Secondly, a parametric analysis of possible improvements in the balance-of-system (BOS) has been developed. Finally, the two steps have been combined with the analysis of crystalline silicon technologies. Results are reported in terms of several indicators: energy pay-back time, CO 2 yield and specific CO 2 emissions. The Indicators show that the integration of PV systems in buildings clearly increases the environmental benefits of present PV technology. These benefits will further increase with future PV technologies. Future optimised PV roof-integrated systems are expected to have an energy pay-back time of around 1-5 years (1 year with heat recovery) and to save during their lifetime more than 20 times the amount of CO 2 emitted during their manufacturing (34 times with heat recovery). (Author)

  8. Feedforward Control Strategy for the state-decoupling Stand-alone UPS with LC output filter

    DEFF Research Database (Denmark)

    Lu, Jinghang; Savaghebi, Mehdi; Guerrero, Josep M.

    2017-01-01

    In this paper, the disturbance rejection performance of the cascaded control strategy for UPS system is investigated. The comparison of closed loop system performance between conventional cascaded control (CCC) strategy and state-decoupling cascaded control (SDCC) strategy are further explored....... In order to further increase the load current disturbance rejection capability of the state-decoupling in UPS system, a feedforward control strategy is proposed. In addition, the design principle for the current and voltage regulators are discussed. Simulation and experimental results are provided...

  9. Modeling & power management of standalone PV-Wind Hybrid energy system for remote location

    Science.gov (United States)

    Shawon, M. J. A.

    This thesis mainly focuses on a novel design of a standalone PV-Wind hybrid energy system for remote locations where grid extension is not feasible or is expensive. The Hybrid PV-Wind standalone energy system shows higher reliability compared to Wind or PV standalone systems as wind and solar are complementary. A Matlab/Simulink model of an integrated standalone PV-Wind hybrid system using a battery for storage and backup protection is presented. The individual component of the system is discussed and modeled. A novel and unique control strategy is designed and simulated to control the power flow of the system while maintaining the battery charging and discharging limit. In addition, different converter design and maximum power point tracking control are applied to ensure efficient and reliable power supply under various atmospheric and loading conditions.

  10. Assessing the influence of the temporal resolution of electrical load and PV generation profiles on self-consumption and sizing of PV-battery systems

    International Nuclear Information System (INIS)

    Beck, T.; Kondziella, H.; Huard, G.; Bruckner, T.

    2016-01-01

    Highlights: • MILP optimization model for operation and investment of PV-battery systems. • Use of high resolution (10 s) electrical household load and PV generation profiles. • Analysis of influence of temporal resolution on self-consumption and optimal sizing. • Electrical load profile characteristics influence required temporal resolution. - Abstract: The interest in self-consumption of electricity generated by rooftop photovoltaic systems has grown in recent years, fueled by decreasing levelized costs of electricity and feed-in tariffs as well as increasing end customer electricity prices in the residential sector. This also fostered research on grid-connected PV-battery storage systems, which are a promising technology to increase self-consumption. In this paper a mixed-integer linear optimization model of a PV-battery system that minimizes the total discounted operating and investment costs is developed. The model is employed to study the effect of the temporal resolution of electrical load and PV generation profiles on the rate of self-consumption and the optimal sizing of PV and PV-battery systems. In contrast to previous studies high resolution (10 s) measured input data for both PV generation and electrical load profiles is used for the analysis. The data was obtained by smart meter measurements in 25 different households in Germany. It is shown that the temporal resolution of load profiles is more critical for the accuracy of the determination of self-consumption rates than the resolution of the PV generation. For PV-systems without additional storage accurate results can be obtained by using 15 min solar irradiation data. The required accuracy for the electrical load profiles depends strongly on the load profile characteristics. While good results can be obtained with 60 s for all electrical load profiles, 15 min data can still be sufficient for load profiles that do not exhibit most of their electricity consumption at power levels above 2 k

  11. Extra-peritoneal pressure packing without external pelvic fixation: A life-saving stand-alone surgical treatment

    Directory of Open Access Journals (Sweden)

    Guy Ron

    2015-01-01

    Full Text Available Purpose: Traditional maneuvers aim to decrease retroperitoneal bleeding in hemodynamically unstable multi-trauma patients with unstable pelvic fractures, are reportedly successful in approximately only 50%. The life-saving effect of extra-peritoneal pressure packing (EPPP is based on direct compression and control of both venous and arterial retroperitoneal bleeders. This study describes the safety and efficacy of emergent EPPP employment, as a stand-alone surgical treatment, that is, carried out without external pelvic fixation or emergent angiography. Materials and Methods: A retrospective chart review of all hemodynamic unstable, multi-trauma patients with mechanically unstable pelvic fractures treated by the EPPP technique at our medical center between the years 2005 and 2011. Survival rates, clinical, and physiological outcomes were followed prospectively. Results: Twenty-five of the 181 pelvic fracture patients had biomechanically unstable fractures that required surgical fixation. Fourteen of those 25 patients had deteriorating hemodynamic instability from massive pelvic bleeding which was resistant to resuscitation, and they underwent EPPP, as a stand-alone treatment. The procedure successfully achieved hemodynamic stability in all 14 patients and obviated the early mortality associated with massive pelvic bleeding. Three of these patients eventually succumbed to their multiple injuries. Conclusion: Implementation of EPPP improved all measured physiological outcome parameters and survival rates of hemodynamically unstable multi-trauma patients with unstable pelvic fractures in our trauma center. It provided the unique advantage of directly compressing the life-threatening retroperitoneal bleeders by applying direct pressure and causing a tamponade effect to stanch venous and arterial pelvic blood flow and obviate the early mortality associated with massive pelvic bleeding.

  12. An ArcGIS analysis of Stand-alone GPS quality for Road Pricing

    DEFF Research Database (Denmark)

    Zabic, Martina

    2006-01-01

    quality and reliability is adequate for implementation of a road pricing system. The GPS log files was imported into ArcGIS and analyzed in relation to the digital road network and the density of the high rise areas in order to examine where the high buildings and narrow street canyons causes too many...

  13. Wind-driven stand-alone DFIG with battery and pumped hydro ...

    Indian Academy of Sciences (India)

    Renewable energy electric conversion system; induction generators; wind power generation; energy storage; power converters. ... converter, (ii) wide speed operation of wind-driven DFIG, (iii) reduced battery capacity, (iv) high energy storage using PHSP and (v) availability of continuous power to the isolated loads.

  14. Long-term field test of solar PV power generation using one-axis 3-position sun tracker

    KAUST Repository

    Huang, B.J.

    2011-09-01

    The 1 axis-3 position (1A-3P) sun tracking PV was built and tested to measure the daily and long-term power generation of the solar PV system. A comparative test using a fixed PV and a 1A-3P tracking PV was carried out with two identical stand-alone solar-powered LED lighting systems. The field test in the particular days shows that the 1A-3P tracking PV can generate 35.8% more electricity than the fixed PV in a partly-cloudy weather with daily-total solar irradiation HT=11.7MJ/m2day, or 35.6% in clear weather with HT=18.5MJ/m2day. This indicates that the present 1A-3P tracking PV can perform very close to a dual-axis continuous tracking PV (Kacira et al., 2004). The long-term outdoor test results have shown that the increase of daily power generation of 1A-3P tracking PV increases with increasing daily-total solar irradiation. The increase of monthly-total power generation for 1A-3P sun tracking PV is between 18.5-28.0%. The total power generation increase in the test period from March 1, 2010 to March 31, 2011, is 23.6% in Taipei (an area of low solar energy resource). The long-term performance of the present 1X-3P tracking PV is shown very close to the 1-axis continuous tracking PV in Taiwan (Chang, 2009). If the 1A-3P tracking PV is used in the area of high solar energy resource with yearly-average HT>17MJ/m2day, the increase of total long-term power generation with respect to fixed PV will be higher than 37.5%. This is very close to that of dual-axis continuous tracking PV. The 1A-3P tracker can be easily mounted on the wall of a building. The cost of the whole tracker is about the same as the regular mounting cost of a conventional rooftop PV system. This means that there is no extra cost for 1A-3P PV mounted on buildings. The 1A-3P PV is quite suitable for building-integrated applications. © 2011 Elsevier Ltd.

  15. High-Performance Constant Power Generation in Grid-Connected PV Systems

    DEFF Research Database (Denmark)

    Sangwongwanich, Ariya; Yang, Yongheng; Blaabjerg, Frede

    2016-01-01

    An advanced power control strategy by limiting the maximum feed-in power of PV systems has been proposed, which can ensure a fast and smooth transition between maximum power point tracking and Constant Power Generation (CPG). Regardless of the solar irradiance levels, high-performance and stable...... operation are always achieved by the proposed control strategy. It can regulate the PV output power according to any set-point, and force the PV systems to operate at the left side of the maximum power point without stability problems. Experimental results have verified the effectiveness of the proposed CPG...

  16. Forecasting and observability: critical technologies for system operations with high PV penetration

    DEFF Research Database (Denmark)

    Alet, Pierre-Jean; Efthymiou, Venizelos; Graditi, Giorgio

    2016-01-01

    Forecasting and monitoring technologies for photovoltaics are required on different spatial and temporal scales by multiple actors, from the owners of PV systems to transmission system operators. In this paper the Grid integration working group of the European Technology and Innovation Platform –...... for a cost/benefit analysis since the forecasting error can be linked to the prices charged for energy imbalance......Forecasting and monitoring technologies for photovoltaics are required on different spatial and temporal scales by multiple actors, from the owners of PV systems to transmission system operators. In this paper the Grid integration working group of the European Technology and Innovation Platform...... – Photovoltaics (ETIP PV) reviews the different use cases for these technologies, their current status, and the need for future developments. Power system operations require a real-time view of PV production for managing power reserves and for feeding shortterm forecasts. They also require forecasts on all...

  17. Realworld maximum power point tracking simulation of PV system based on Fuzzy Logic control

    Directory of Open Access Journals (Sweden)

    Ahmed M. Othman

    2012-12-01

    Full Text Available In the recent years, the solar energy becomes one of the most important alternative sources of electric energy, so it is important to improve the efficiency and reliability of the photovoltaic (PV systems. Maximum power point tracking (MPPT plays an important role in photovoltaic power systems because it maximize the power output from a PV system for a given set of conditions, and therefore maximize their array efficiency. This paper presents a maximum power point tracker (MPPT using Fuzzy Logic theory for a PV system. The work is focused on the well known Perturb and Observe (P&O algorithm and is compared to a designed fuzzy logic controller (FLC. The simulation work dealing with MPPT controller; a DC/DC Ćuk converter feeding a load is achieved. The results showed that the proposed Fuzzy Logic MPPT in the PV system is valid.

  18. Alignment of the CMS Silicon Strip Tracker during stand-alone Commissioning

    CERN Document Server

    Adam, W; Dragicevic, M; Friedl, M; Frühwirth, R; Hansel, S; Hrubec, J; Krammer, M; Oberegger, M; Pernicka, M; Schmid, S; Stark, R; Steininger, H; Uhl, D; Waltenberger, W; Widl, E; Van Mechelen, P; Cardaci, M; Beaumont, W; de Langhe, E; de Wolf, E A; Delmeire, E; Hashemi, M; Bouhali, O; Charaf, O; Clerbaux, B; Dewulf, J P; Elgammal, S; Hammad, G; de Lentdecker, G; Marage, P; Vander Velde, C; Vanlaer, P; Wickens, J; Adler, V; Devroede, O; De Weirdt, S; D'Hondt, J; Goorens, R; Heyninck, J; Maes, J; Mozer, Matthias Ulrich; Tavernier, S; Van Lancker, L; Van Mulders, P; Villella, I; Wastiels, C; Bonnet, J L; Bruno, G; De Callatay, B; Florins, B; Giammanco, A; Gregoire, G; Keutgen, Th; Kcira, D; Lemaitre, V; Michotte, D; Militaru, O; Piotrzkowski, K; Quertermont, L; Roberfroid, V; Rouby, X; Teyssier, D; daubie, E; Anttila, E; Czellar, S; Engström, P; Härkönen, J; Karimäki, V; Kostesmaa, J; Kuronen, A; Lampén, T; Lindén, T; Luukka, P R; Mäenää, T; Michal, S; Tuominen, E; Tuominiemi, J; Ageron, M; Baulieu, G; Bonnevaux, A; Boudoul, G; Chabanat, E; Chabert, E; Chierici, R; Contardo, D; Della Negra, R; Dupasquier, T; Gelin, G; Giraud, N; Guillot, G; Estre, N; Haroutunian, R; Lumb, N; Perries, S; Schirra, F; Trocme, B; Vanzetto, S; Agram, J L; Blaes, R; Drouhin, F; Ernenwein, J P; Fontaine, J C; Berst, J D; Brom, J M; Didierjean, F; Goerlach, U; Graehling, P; Gross, L; Hosselet, J; Juillot, P; Lounis, A; Maazouzi, C; Olivetto, C; Strub, R; Van Hove, P; Anagnostou, G; Brauer, R; Esser, H; Feld, L; Karpinski, W; Klein, K; Kukulies, C; Olzem, J; Ostapchuk, A; Pandoulas, D; Pierschel, G; Raupach, F; Schael, S; Schwering, G; Sprenger, D; Thomas, M; Weber, M; Wittmer, B; Wlochal, M; Beissel, F; Bock, E; Flugge, G; Gillissen, C; Hermanns, T; Heydhausen, D; Jahn, D; Kaussen, G; Linn, A; Perchalla, L; Poettgens, M; Pooth, O; Stahl, A; Zoeller, M H; Buhmann, P; Butz, E; Flucke, G; Hamdorf, R; Hauk, J; Klanner, R; Pein, U; Schleper, P; Steinbrück, G; Blüm, P; De Boer, W; Dierlamm, A; Dirkes, G; Fahrer, M; Frey, M; Furgeri, A; Hartmann, F; Heier, S; Hoffmann, K H; Kaminski, J; Ledermann, B; Liamsuwan, T; Müller, S; Müller, Th; Schilling, F P; Simonis, H J; Steck, P; Zhukov, V; Cariola, P; De Robertis, G; Ferorelli, R; Fiore, L; Preda, M; Sala, G; Silvestris, L; Tempesta, P; Zito, G; Creanza, D; De Filippis, N; De Palma, M; Giordano, D; Maggi, G; Manna, N; My, S; Selvaggi, G; Albergo, S; Chiorboli, M; Costa, S; Galanti, M; Giudice, N; Guardone, N; Noto, F; Potenza, R; Saizu, M A; Sparti, V; Sutera, C; Tricomi, A; Tuve, C; Brianzi, M; Civinini, C; Maletta, F; Manolescu, F; Meschini, M; Paoletti, S; Sguazzoni, G; Broccolo, B; Ciulli, V; D'Alessandro, R; Focardi, E; Frosali, S; Genta, C; Landi, G; Lenzi, P; Macchiolo, A; Magini, N; Parrini, G; Scarlini, E; Cerati, G; Azzi, P; Bacchetta, N; Candelori, A; Dorigo, T; Kaminsky, A; Karaevski, S; Khomenkov, V; Reznikov, S; Tessaro, M; Bisello, D; De Mattia, M; Giubilato, P; Loreti, M; Mattiazzo, S; Nigro, M; Paccagnella, A; Pantano, D; Pozzobon, N; Tosi, M; Bilei, G M; Checcucci, B; Fanò, L; Servoli, L; Ambroglini, F; Babucci, E; Benedetti, D; Biasini, M; Caponeri, B; Covarelli, R; Giorgi, M; Lariccia, P; Mantovani, G; Marcantonini, M; Postolache, V; Santocchia, A; Spiga, D; Bagliesi, G; Balestri, G; Berretta, L; Bianucci, S; Boccali, T; Bosi, F; Bracci, F; Castaldi, R; Ceccanti, M; Cecchi, R; Cerri, C; Cucoanes, A S; Dell'Orso, R; Dobur, D; Dutta, S; Giassi, A; Giusti, S; Kartashov, D; Kraan, A; Lomtadze, T; Lungu, G A; Magazzu, G; Mammini, P; Mariani, F; Martinelli, G; Moggi, A; Palla, F; Palmonari, F; Petragnani, G; Profeti, A; Raffaelli, F; Rizzi, D; Sanguinetti, G; Sarkar, S; Sentenac, D; Serban, A T; Slav, A; Soldani, A; Spagnolo, P; Tenchini, R; Tolaini, S; Venturi, A; Verdini, P G; Vos, M; Zaccarelli, L; Avanzini, C; Basti, A; Benucci, L; Bocci, A; Cazzola, U; Fiori, F; Linari, S; Massa, M; Messineo, A; Segneri, G; Tonelli, G; Azzurri, P; Bernardini, J; Borrello, L; Calzolari, F; Foà, L; Gennai, S; Ligabue, F; Petrucciani, G; Rizzi, A; Yang, Z; Benotto, F; Demaria, N; Dumitrache, F; Farano, R; Borgia, M A; Castello, R; Costa, M; Migliore, E; Romero, A; Abbaneo, D; Abbas, M; Ahmed, I; Akhtar, I; Albert, E; Bloch, C; Breuker, H; Butt, S; Buchmuller, O; Cattai, A; Delaere, C; Delattre, M; Edera, L M; Engstrom, P; Eppard, M; Gateau, M; Gill, K; Giolo-Nicollerat, A S; Grabit, R; Honma, A; Huhtinen, M; Kloukinas, K; Kortesmaa, J; Kottelat, L J; Kuronen, A; Leonardo, N; Ljuslin, C; Mannelli, M; Masetti, L; Marchioro, A; Mersi, S; Michal, S; Mirabito, L; Muffat-Joly, J; Onnela, A; Paillard, C; Pal, I; Pernot, J F; Petagna, P; Petit, P; Piccut, C; Pioppi, M; Postema, H; Ranieri, R; Ricci, D; Rolandi, G; Ronga, F; Sigaud, C; Syed, A; Siegrist, P; Tropea, P; Troska, J; Tsirou, A; Vander Donckt, M; Vasey, F; Alagoz, E; Amsler, Claude; Chiochia, V; Regenfus, Christian; Robmann, P; Rochet, J; Rommerskirchen, T; Schmidt, A; Steiner, S; Wilke, L; Church, I; Cole, J; Coughlan, J; Gay, A; Taghavi, S; Tomalin, I; Bainbridge, R; Cripps, N; Fulcher, J; Hall, G; Noy, M; Pesaresi, M; Radicci, V; Raymond, D M; Sharp, P; Stoye, M; Wingham, M; Zorba, O; Goitom, I; Hobson, P R; Reid, I; Teodorescu, L; Hanson, G; Jeng, G Y; Liu, H; Pasztor, G; Satpathy, A; Stringer, R; Mangano, B; Affolder, K; Affolder, T; Allen, A; Barge, D; Burke, S; Callahan, D; Campagnari, C; Crook, A; D'Alfonso, M; Dietch, J; Garberson, Jeffrey Ford; Hale, D; Incandela, H; Incandela, J; Jaditz, S; Kalavase, P; Kreyer, S; Kyre, S; Lamb, J; Mc Guinnessr, C; Mills, C; Nguyen, H; Nikolic, M; Lowette, S; Rebassoo, F; Ribnik, J; Richman, J; Rubinstein, N; Sanhueza, S; Shah, Y; Simms, L; Staszak, D; Stoner, J; Stuart, D; Swain, S; Vlimant, J R; White, D; Ulmer, K A; Wagner, S R; Bagby, L; Bhat, P C; Burkett, K; Cihangir, S; Gutsche, O; Jensen, H; Johnson, M; Luzhetskiy, N; Mason, D; Miao, T; Moccia, S; Noeding, C; Ronzhin, A; Skup, E; Spalding, W J; Spiegel, L; Tkaczyk, S; Yumiceva, F; Zatserklyaniy, A; Zerev, E; Anghel, I; Bazterra, V E; Gerber, C E; Khalatian, S; Shabalina, E; Baringer, P; Bean, A; Chen, J; Hinchey, C; Martin, C; Moulik, T; Robinson, R; Gritsan, A V; Lae, C K; Tran, N V; Everaerts, P; Hahn, K A; Harris, P; Nahn, S; Rudolph, M; Sung, K; Betchart, B; Demina, R; Gotra, Y; Korjenevski, S; Miner, D; Orbaker, D; Christofek, L; Hooper, R; Landsberg, G; Nguyen, D; Narain, M; Speer, T; Tsang, K V

    2009-01-01

    The results of the CMS tracker alignment analysis are presented using the data from cosmic tracks, optical survey information, and the laser alignment system at the Tracker Integration Facility at CERN. During several months of operation in the spring and summer of 2007, about five million cosmic track events were collected with a partially active CMS Tracker. This allowed us to perform first alignment of the active silicon modules with the cosmic tracks using three different statistical approaches; validate the survey and laser alignment system performance; and test the stability of Tracker structures under various stresses and temperatures ranging from +15C to -15C. Comparison with simulation shows that the achieved alignment precision in the barrel part of the tracker leads to residual distributions similar to those obtained with a random misalignment of 50 (80) microns in the outer (inner) part of the barrel.

  19. Experimental stand-alone self-excited induction generator driven by a diesel motor

    Directory of Open Access Journals (Sweden)

    Mhamdi Taoufik

    2017-12-01

    Full Text Available This paper presents an experimental work to design and size a diesel generator (DG. The basic system is equipped with a 1.5 kW self-excited induction generator (SEIG, a diesel motor (DM, a static voltage compensator (SVC and controllers. A proportional integral controller is used to meet the requirement of the SEIG frequency regulation. A controlled voltage source is performed by using an SVC with a fuzzy controller, which adjusts voltage by varying the amount of the injected reactive power. An experimental set-up is used to identify the SEIG parameters and select the convenient bank of capacitors that minimize the SEIG starting up time and fix the convenient margin of voltage. The system has been tested by simulation using models implemented by Matlab/Simulink software. The simulation results confirm the efficiency of the proposed strategy of voltage regulation. Keywords: Diesel motor, SEIG, SVC, Voltage regulation, Frequency regulation

  20. Development of stand-alone risk assessment software for optimized maintenance planning of power plant facilities

    International Nuclear Information System (INIS)

    Choi, Woo Sung; Song, Gee Wook; Kim, Bum Shin; Chang, Sung Ho; Lee, Sang Min

    2015-01-01

    Risk-Risk-based inspection (RBI) has been developed in order to identify risky equipment that can cause major accidents or damages in large-scale plants. This assessment evaluates the equipment's risk, categorizes their priorities based on risk level, and then determines the urgency of their maintenance or allocates maintenance resources. An earlier version of the risk-based assessment software is already installed within the equipment management system; however, the assessment is based on examination by an inspector, and the results can be influenced by his subjective judgment, rather than assessment being based on failure probability. Moreover, the system is housed within a server, which limits the inspector's work space and time, and such a system can be used only on site. In this paper, the development of independent risk-based assessment software is introduced; this software calculates the failure probability by an analytical method, and analyzes the field inspection results, as well as inspection effectiveness. It can also operate on site, since it can be installed on an independent platform, and has the ability to generate an I/O function for the field inspection results regarding the period for an optimum maintenance cycle. This program will provide useful information not only to the field users who are participating in maintenance, but also to the engineers who need to decide whether to extend the life cycle of the power machinery or replace only specific components

  1. Development of Stand-Alone Risk Assessment Software for Optimized Maintenance Planning of Power Plant Facilities

    International Nuclear Information System (INIS)

    Choi, Woo Sung; Song, Gee Wook; Kim, Bum Shin; Chang, Sung Ho; Lee, Sang Min

    2015-01-01

    Risk-Risk-based inspection (RBI) has been developed in order to identify risky equipment that can cause major accidents or damages in large-scale plants. This assessment evaluates the equipment s risk, categorizes their priorities based on risk level, and then determines the urgency of their maintenance or allocates maintenance resources. An earlier version of the risk-based assessment software is already installed within the equipment management system; however, the assessment is based on examination by an inspector, and the results can be influenced by his subjective judgment, rather than assessment being based on failure probability. Moreover, the system is housed within a server, which limits the inspector s work space and time, and such a system can be used only on site. In this paper, the development of independent risk-based assessment software is introduced; this software calculates the failure probability by an analytical method, and analyzes the field inspection results, as well as inspection effectiveness. It can also operate on site, since it can be installed on an independent platform, and has the ability to generate an I/O function for the field inspection results regarding the period for an optimum maintenance cycle. This program will provide useful information not only to the field users who are participating in maintenance, but also to the engineers who need to decide whether to extend the life cycle of the power machinery or replace only specific components

  2. Research Survey on Various MPPT Performance Issues to Improve the Solar PV System Efficiency

    Directory of Open Access Journals (Sweden)

    B. Pakkiraiah

    2016-01-01

    Full Text Available Nowadays in order to meet the increase in power demands and to reduce the global warming, renewable energy sources based system is used. Out of the various renewable energy sources, solar energy is the main alternative. But, compared to other sources, the solar panel system converts only 30–40% of solar irradiation into electrical energy. In order to get maximum output from a PV panel system, an extensive research has been underway for long time so as to access the performance of PV system and to investigate the various issues related to the use of solar PV system effectively. This paper therefore presents different types of PV panel systems, maximum power point tracking control algorithms, power electronic converters usage with control aspects, various controllers, filters to reduce harmonic content, and usage of battery system for PV system. Attempts have been made to highlight the current and future issues involved in the development of PV system with improved performance. A list of 185 research publications on this is appended for reference.

  3. A small grid-connected PV system controlled by the PLC

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Dan; Jiang, Zhijian; Li, Yingzhi; Fan, Qing [Beijing University of Civil Engineering and Architecture, Beijing (China)

    2008-07-01

    A new working of the PV system is proposed in this paper. The general solar power generation system can intelligently switch into three work models by the programmable logic controller, including power supply, power storage and grid-connection, The power curve of the PV system can be summarized from the generation data detected by the data acquisition system, compared with the power curve of the various binary combined air-condition loads, we can identify the optimal matching control strategy between the PV system and the combined air-condition loads. The solar power generation system can charge the battery, so the storage power will be converted into AC for the load by independent inverter when the PV power is insufficient; the PV system also can intelligently convey energy to the grid, the grid has the two-way transmission function, in other words, the grid also supply the energy to the load if the PV system fail to drive the load. All in all, the system is capable of bi-direction power transfer. (orig.)

  4. Development and implementation of a PV performance monitoring system based on inverter measurements

    DEFF Research Database (Denmark)

    Spataru, Sergiu; Gavriluta, Anamaria Florina; Maaløe, Lars

    2016-01-01

    currently the cost of the performance monitoring hardware and implementation is high. Therefore, we present the practical development and implementation of a PV performance monitoring system for residential and commercial PV applications, where the cost of the monitoring hardware is lowered, by using......Performance monitoring and fault detection systems have become necessary for decreasing operation and maintenance cost in large photovoltaic (PV) plants, as well for maximizing plan yield and lifetime. We expect a similar development for residential and commercial PV system applications, where...... the inverter’s own monitoring and communication capabilities. We also aim to lower the implementation cost, by using a simple, but accurate performance monitoring approach, and show the practical issues that can arise when implementing such a system....

  5. Fuzzy Secondary Controller for Autonomous Stand-alone and Grid-connected AC Microgrid

    DEFF Research Database (Denmark)

    Neves, Rodolpho V. A.; Machado, Ricardo Q.; Oliveira, Vilma A.

    2016-01-01

    The present paper adresses the AC microgrid control issue using the hierarchical control structure and droop controllers for load sharing. Once the droop controllers impose an operation with frequency and voltage deviations, depending on the load and droop parameters, a hierarchical control...... structure must be added to change the droop controller operating points. The hierarchical controllers operate with local measurements and shared signals from communication links among the distributed generation systems connected to the microgrid. Depending on the geographical size of the microgrid......, the communication links can be economically unviable. This paper thus proposes a fuzzy secondary controller for AC microgrids to reduce the link communication dependency by using only local measurements. The simulation results show that the deviations as happened with the conventional secondary controllers can...

  6. X-ray microbeam stand-alone facility for cultured cells irradiation

    International Nuclear Information System (INIS)

    Bożek, Sebastian; Bielecki, Jakub; Wiecheć, Anna; Lekki, Janusz; Stachura, Zbigniew; Pogoda, Katarzyna; Lipiec, Ewelina; Tkocz, Konrad; Kwiatek, Wojciech M.

    2017-01-01

    Highlights: • An X-ray microbeam line for irradiation of living cultured cells was constructed. • A step by step explanation of working principles with engineering details, procedures and calculations is presented. • A model of beam and cell interaction is presented. • A method of uniform irradiation of living cells with an exact dose per a cell is presented. • Results of preliminary experiments are presented. - Abstract: The article describes an X-ray microbeam standalone facility dedicated for irradiation of living cultured cells. The article can serve as an advice for such facilities construction, as it begins from engineering details, through mathematical modeling and experimental procedures, ending up with preliminary experimental results and conclusions. The presented system consists of an open type X-ray tube with microfocusing down to about 2 μm, an X-ray focusing system with optical elements arranged in the nested Kirckpatrick-Baez (or Montel) geometry, a sample stand and an optical microscope with a scientific digital CCD camera. For the beam visualisation an X-ray sensitive CCD camera and a spectral detector are used, as well as a scintillator screen combined with the microscope. A method of precise one by one irradiation of previously chosen cells is presented, as well as a fast method of uniform irradiation of a chosen sample area. Mathematical models of beam and cell with calculations of kerma and dose are presented. The experiments on dose-effect relationship, kinetics of DNA double strand breaks repair, as well as micronuclei observation were performed on PC-3 (Prostate Cancer) cultured cells. The cells were seeded and irradiated on Mylar foil, which covered a hole drilled in the Petri dish. DNA lesions were visualised with γ-H2AX marker combined with Alexa Fluor 488 fluorescent dye.

  7. Continuous stand-alone controllable aerosol/cloud droplet dryer for atmospheric sampling

    Science.gov (United States)

    Sjogren, S.; Frank, G. P.; Berghof, M. I. A.; Martinsson, B. G.

    2013-02-01

    We describe a general-purpose dryer designed for continuous sampling of atmospheric aerosol, where a specified relative humidity (RH) of the sample flow (lower than the atmospheric humidity) is required. It is often prescribed to measure the properties of dried aerosol, for instance for monitoring networks. The specific purpose of our dryer is to dry cloud droplets (maximum diameter approximately 25 μm, highly charged, up to 5 × 102 charges). One criterion is to minimise losses from the droplet size distribution entering the dryer as well as on the residual dry particle size distribution exiting the dryer. This is achieved by using a straight vertical downwards path from the aerosol inlet mounted above the dryer, and removing humidity to a dry, closed loop airflow on the other side of a semi-permeable GORE-TEX membrane (total area 0.134 m2). The water vapour transfer coefficient, k, was measured to be 4.6 × 10-7 kg m-2 s-1% RH-1 in the laboratory (temperature 294 K) and is used for design purposes. A net water vapour transfer rate of up to 1.2 × 10-6 kg s-1 was achieved in the field. This corresponds to drying a 5.7 L min-1 (0.35 m3 h-1) aerosol sample flow from 100% RH to 27% RH at 293 K (with a drying air total flow of 8.7 L min-1). The system was used outdoors from 9 May until 20 October 2010, on the mountain Brocken (51.80° N, 10.67° E, 1142 m a.s.l.) in the Harz region in central Germany. Sample air relative humidity of less than 30% was obtained 72% of the time period. The total availability of the measurement system was >94% during these five months.

  8. X-ray microbeam stand-alone facility for cultured cells irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Bożek, Sebastian, E-mail: sebastian.bozek@yahoo.com [Jagiellonian University Medical College, Department of Pharmaceutical Biophysics, Krakow (Poland); Bielecki, Jakub; Wiecheć, Anna; Lekki, Janusz; Stachura, Zbigniew; Pogoda, Katarzyna; Lipiec, Ewelina; Tkocz, Konrad; Kwiatek, Wojciech M. [Institute of Nuclear Physics Polish Academy of Sciences, PL-31342 Krakow (Poland)

    2017-03-01

    Highlights: • An X-ray microbeam line for irradiation of living cultured cells was constructed. • A step by step explanation of working principles with engineering details, procedures and calculations is presented. • A model of beam and cell interaction is presented. • A method of uniform irradiation of living cells with an exact dose per a cell is presented. • Results of preliminary experiments are presented. - Abstract: The article describes an X-ray microbeam standalone facility dedicated for irradiation of living cultured cells. The article can serve as an advice for such facilities construction, as it begins from engineering details, through mathematical modeling and experimental procedures, ending up with preliminary experimental results and conclusions. The presented system consists of an open type X-ray tube with microfocusing down to about 2 μm, an X-ray focusing system with optical elements arranged in the nested Kirckpatrick-Baez (or Montel) geometry, a sample stand and an optical microscope with a scientific digital CCD camera. For the beam visualisation an X-ray sensitive CCD camera and a spectral detector are used, as well as a scintillator screen combined with the microscope. A method of precise one by one irradiation of previously chosen cells is presented, as well as a fast method of uniform irradiation of a chosen sample area. Mathematical models of beam and cell with calculations of kerma and dose are presented. The experiments on dose-effect relationship, kinetics of DNA double strand breaks repair, as well as micronuclei observation were performed on PC-3 (Prostate Cancer) cultured cells. The cells were seeded and irradiated on Mylar foil, which covered a hole drilled in the Petri dish. DNA lesions were visualised with γ-H2AX marker combined with Alexa Fluor 488 fluorescent dye.

  9. Performance power evaluation of DC fan cooling system for PV panel by using ANSYS CFX

    Science.gov (United States)

    Syafiqah, Z.; Amin, N. A. M.; Irwan, Y. M.; Irwanto, M.; Leow, W. Z.; Amelia, A. R.

    2017-09-01

    A research has been conducted to find the optimum combination for DC fan air cooling system of photovoltaic (PV) panel. During normal operation of PV panel, it is estimated that only 15 % of solar radiation is converted into electrical energy. Meanwhile, the rest of the solar radiation is converted into heat energy which affects the performance of the PV panel. Therefore, the aim of this research is to investigate the performance power evaluation of DC fan cooling system for PV panel by using ANSYS CFX. The effect of airflow configuration of DC fan has been investigated. This is to analyze whether the airflow circulation of DC fan cause a change towards the maximum temperature of PV panel. Besides, the impact of varying number of DC fans attached at the back of PV panel is evaluated. The result of airflow circulation of DC fan has been discussed. Meanwhile, with the increment number of DC fans, the PV panel temperature drops significantly. As a conclusion, the optimum number of DC fans is two with the combination of inlet airflow.

  10. PV Systems Reliability Final Technical Report: Ground Fault Detection

    Energy Technology Data Exchange (ETDEWEB)

    Lavrova, Olga [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Flicker, Jack David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Johnson, Jay [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-01-01

    We have examined ground faults in PhotoVoltaic (PV) arrays and the efficacy of fuse, current detection (RCD), current sense monitoring/relays (CSM), isolation/insulation (Riso) monitoring, and Ground Fault Detection and Isolation (GFID) using simulations based on a Simulation Program with Integrated Circuit Emphasis SPICE ground fault circuit model, experimental ground faults installed on real arrays, and theoretical equations.

  11. Continuous stand-alone controllable aerosol/cloud droplet dryer for atmospheric sampling

    Directory of Open Access Journals (Sweden)

    S. Sjogren

    2013-02-01

    Full Text Available We describe a general-purpose dryer designed for continuous sampling of atmospheric aerosol, where a specified relative humidity (RH of the sample flow (lower than the atmospheric humidity is required. It is often prescribed to measure the properties of dried aerosol, for instance for monitoring networks. The specific purpose of our dryer is to dry cloud droplets (maximum diameter approximately 25 μm, highly charged, up to 5 × 102 charges. One criterion is to minimise losses from the droplet size distribution entering the dryer as well as on the residual dry particle size distribution exiting the dryer. This is achieved by using a straight vertical downwards path from the aerosol inlet mounted above the dryer, and removing humidity to a dry, closed loop airflow on the other side of a semi-permeable GORE-TEX membrane (total area 0.134 m2.

    The water vapour transfer coefficient, k, was measured to be 4.6 × 10-7 kg m−2 s−1% RH−1 in the laboratory (temperature 294 K and is used for design purposes. A net water vapour transfer rate of up to 1.2 × 10-6 kg s−1 was achieved in the field. This corresponds to drying a 5.7 L min−1 (0.35 m3 h−1 aerosol sample flow from 100% RH to 27% RH at 293 K (with a drying air total flow of 8.7 L min−1. The system was used outdoors from 9 May until 20 October 2010, on the mountain Brocken (51.80° N, 10.67° E, 1142 m a.s.l. in the Harz region in central Germany. Sample air relative humidity of less than 30% was obtained 72% of the time period. The total availability of the measurement system was >94% during these five months.

  12. MPA Portable: A Stand-Alone Software Package for Analyzing Metaproteome Samples on the Go.

    Science.gov (United States)

    Muth, Thilo; Kohrs, Fabian; Heyer, Robert; Benndorf, Dirk; Rapp, Erdmann; Reichl, Udo; Martens, Lennart; Renard, Bernhard Y

    2018-01-02

    Metaproteomics, the mass spectrometry-based analysis of proteins from multispecies samples faces severe challenges concerning data analysis and results interpretation. To overcome these shortcomings, we here introduce the MetaProteomeAnalyzer (MPA) Portable software. In contrast to the original server-based MPA application, this newly developed tool no longer requires computational expertise for installation and is now independent of any relational database system. In addition, MPA Portable now supports state-of-the-art database search engines and a convenient command line interface for high-performance data processing tasks. While search engine results can easily be combined to increase the protein identification yield, an additional two-step workflow is implemented to provide sufficient analysis resolution for further postprocessing steps, such as protein grouping as well as taxonomic and functional annotation. Our new application has been developed with a focus on intuitive usability, adherence to data standards, and adaptation to Web-based workflow platforms. The open source software package can be found at https://github.com/compomics/meta-proteome-analyzer .

  13. User acceptance of diesel/PV hybrid system in an island community

    International Nuclear Information System (INIS)

    Phuangpornpitak, N.; Kumar, S.

    2011-01-01

    This paper presents the results of a study conducted at a rural (island) community to understand the role of PV hybrid system installed on an island. Until 2004, most islanders had installed diesel generators in their homes to generate electricity, which was directly supplied to appliances or stored in the batteries for later use. A field survey was carried out to study the user satisfaction of the PV hybrid system in the island community. The attitude of islanders to the PV hybrid system was mostly positive. The islanders can use more electricity, the supply of which can meet the demand. A comparison of pollutions before and after installation of the PV hybrid system was made along with the interviews with the users. The data show that the users are highly satisfied with the PV hybrid system which can reduce environmental impact, especially air and noise pollutions. New opportunities as a result of access to electric service include studying and reading at night that were not possible earlier. All the islanders use the PV hybrid system and more importantly, no one found that the system made their life worse as compared to the earlier state of affairs. (author)

  14. Performance evaluation of a 2-mode PV grid connected system in Thailand -- Case study

    Energy Technology Data Exchange (ETDEWEB)

    Jivacate, C.; Mongconvorawan, S.; Sinratanapukdee, E.; Limsawatt, W. [Electricity Generating Authority of Thailand, Nontha Buri (Thailand)

    1994-12-31

    A PV grid connected system with small battery bank has been set up in a rural district, North Thailand in order to demonstrate a 2-mode operation concept. The objective is to gain experience on the PV grid connected concept without battery storage. However, due to the evening peak demand and a rather weak distribution grid which is typical in rural areas, small battery bank is still required to enable the maximum energy transfer to grid for the time being before moving fully to the no battery mode. The analyzed data seems to indicate possible performance improvement by re-arranging the number of PV modules and battery in the string.

  15. A Sensorless Power Reserve Control Strategy for Two-Stage Grid-Connected PV Systems

    DEFF Research Database (Denmark)

    Sangwongwanich, Ariya; Yang, Yongheng; Blaabjerg, Frede

    2017-01-01

    Due to the still increasing penetration of grid-connected Photovoltaic (PV) systems, advanced active power control functionalities have been introduced in grid regulations. A power reserve control, where namely the active power from the PV panels is reserved during operation, is required for grid...... to achieve the power reserve. In this method, the solar irradiance and temperature measurements that have been used in conventional power reserve control schemes to estimate the available PV power are not required, and thereby being a sensorless approach with reduced cost. Experimental tests have been...

  16. Leadership in Dental Hygiene Degree Completion Programs: A Pilot Study Comparing Stand-Alone Leadership Courses and Leadership-Infused Curricula.

    Science.gov (United States)

    Smith, Michelle L; Gurenlian, JoAnn R; Freudenthal, Jacqueline J; Farnsworth, Tracy J

    2016-05-01

    The aim of this study was to define the extent to which leadership and leadership skills are taught in dental hygiene degree completion programs by comparing stand-alone leadership courses/hybrid programs with programs that infuse leadership skills throughout the curricula. The study involved a mixed-methods approach using qualitative and quantitative data. Semi-structured interviews were conducted with program directors and faculty members who teach a stand-alone leadership course, a hybrid program, or leadership-infused courses in these programs. A quantitative comparison of course syllabi determined differences in the extent of leadership content and experiences between stand-alone leadership courses and leadership-infused curricula. Of the 53 U.S. dental hygiene programs that offer degree completion programs, 49 met the inclusion criteria, and 19 programs provided course syllabi. Of the program directors and faculty members who teach a stand-alone leadership course or leadership-infused curriculum, 16 participated in the interview portion of the study. The results suggested that competencies related to leadership were not clearly defined or measurable in current teaching. Reported barriers to incorporating a stand-alone leadership course included overcrowded curricula, limited qualified faculty, and lack of resources. The findings of this study provide a synopsis of leadership content and gaps in leadership education for degree completion programs. Suggested changes included defining a need for leadership competencies and providing additional resources to educators such as courses provided by the American Dental Education Association and the American Dental Hygienists' Association.

  17. Maximum power point tracking techniques for photovoltaic water pumping system

    OpenAIRE

    Aashoor, Fathi

    2015-01-01

    An investigation into the design of a stand-alone photovoltaic water pumping system for supplying rural areas is presented. It includes a study of system components and their modelling. The PV water pumping system comprises a solar-cell-array, DC-DC buck chopper and permanent-magnet DC motor driving a centrifugal pump. The thesis focuses on increasing energy extraction by improving maximum power point tracking (MPPT). From different MPPT techniques previously proposed, the perturb and observe...

  18. Investigation of energy management strategies for photovoltaic systems - An analysis technique

    Science.gov (United States)

    Cull, R. C.; Eltimsahy, A. H.

    1982-01-01

    Progress is reported in formulating energy management strategies for stand-alone PV systems, developing an analytical tool that can be used to investigate these strategies, applying this tool to determine the proper control algorithms and control variables (controller inputs and outputs) for a range of applications, and quantifying the relative performance and economics when compared to systems that do not apply energy management. The analysis technique developed may be broadly applied to a variety of systems to determine the most appropriate energy management strategies, control variables and algorithms. The only inputs required are statistical distributions for stochastic energy inputs and outputs of the system and the system's device characteristics (efficiency and ratings). Although the formulation was originally driven by stand-alone PV system needs, the techniques are also applicable to hybrid and grid connected systems.

  19. Highlight of Grid-connected PV systems in administrative buildings in Egypt

    Directory of Open Access Journals (Sweden)

    Dina Said

    2017-03-01

    Full Text Available Solar energy applications are becoming increasingly common in Egypt. The abundant sunshine in Egypt, as well as the increasing competitiveness of solar energy systems including- but not limited to photovoltaic (PV, – predicts that these technologies could be weighed to be raised in Egypt.PV systems are installed on roof tiles or other parts of building structures to supplement grid utility, reduce electric bills, and provide emergency back–up energy. Moreover, they simultaneously reduce significant amounts of CO2 emissions. It is foreseen, a number of residential and public buildings in Egypt are using solar power to cut electric utility bills significantly. The approximately payback period to recover the investment costs for PV systems is up to about 5 years.  In addition, it is more economical to use PV system than grid utility systems. The two components that determine the total initial price of a grid- connected PV system are the modules and the balance of systems (BOS. The BOS includes different components such as mounting frames, inverters and site- specific installation hardware.The Government of Egypt (GOE has endorsed the deployment of PV systems through three approaches. It started with a prime minister decree to install PV projects on one-thousand of the governmental buildings. This was followed by as an initiative called "Shamsk ya Masr", and finally the Feed-in Tariff (FiT projects.Following the prime minster decree the Egyptian Electricity Holding Company (EEHC and its affiliated companies took the lead to install PV systems at the top roof of their administrative buildings and interconnect these systems to the electricity network where the suitable locations have been selected for mounting them. About 90 PV systems have been already mounted with about a capacity of 9 MW. On the other hand, "Shamsk ya Masr" has considered energy efficiency (EE so as to complement the PV systems, which will be installed on administrative

  20. A Modular PV System Using Chain-Link-Type Multilevel Converter

    Science.gov (United States)

    Hatano, Nobuhiko; Ise, Toshifumi

    This paper presents a modular photovoltaic system (MPVS) that uses a chain-link-type multilevel converter (CLMC). In large-scale PV generating systems, the DC power supply is generally composed of a large number of PV panels. Hence, losses are caused by differences in the maximum power point at each PV panel. An MPVS has been proposed to address the above mentioned problem. It helps improve the photoelectric conversion efficiency by applying maximum power point tracking (MPPT) control to each group of PV panels. In addition, if a CLMC is used in an MPVS, a high voltage can be output from the AC side and transmission losses can be decreased. However, with this circuit configuration, the current output from the AC side may be unbalanced. Therefore, we propose a method to output balanced current from the AC side, even if the output of the DC power supply is unbalanced. The validity of the proposed method is examined by digital simulation.

  1. Efficiency improvement of the maximum power point tracking for PV systems using support vector machine technique

    Science.gov (United States)

    Kareim, Ameer A.; Mansor, Muhamad Bin

    2013-06-01

    The aim of this paper is to improve efficiency of maximum power point tracking (MPPT) for PV systems. The Support Vector Machine (SVM) was proposed to achieve the MPPT controller. The theoretical, the perturbation and observation (P&O), and incremental conductance (IC) algorithms were used to compare with proposed SVM algorithm. MATLAB models for PV module, theoretical, SVM, P&O, and IC algorithms are implemented. The improved MPPT uses the SVM method to predict the optimum voltage of the PV system in order to extract the maximum power point (MPP). The SVM technique used two inputs which are solar radiation and ambient temperature of the modeled PV module. The results show that the proposed SVM technique has less Root Mean Square Error (RMSE) and higher efficiency than P&O and IC methods.

  2. IMPROVED VARIABLE STEP SIZE INCREMENTAL CONDUCTANCE MPPT METHOD WITH HIGH CONVERGENCE SPEED FOR PV SYSTEMS

    Directory of Open Access Journals (Sweden)

    BEHZAD AZIZIAN ISALOO

    2016-04-01

    Full Text Available Maximum power point tracking (MPPT algorithms are employed in photovoltaic (PV systems to provide full utilization of PV array output power. Among all the MPPT algorithms, the Incremental Conductance (INC algorithm is widely used in PV systems due to the high tracking speed and accuracy. In this paper an improved variable step size algorithm which is based on incremental conductance algorithm is proposed that adjusts the step size according to PV output current. The result of this adaption is to make the algorithm suitable for practical operating conditions due to a wider operating range of irradiation changes. Simulation results confirm that the proposed algorithm increases convergence speed and efficiency in comparison with conventional fixed and variable step size INC algorithms.

  3. Designing PV Incentive Programs to Promote System Performance: AReview of Current Practice

    Energy Technology Data Exchange (ETDEWEB)

    Barbose, Galen; Wiser, Ryan; Bolinger, Mark

    2006-11-12

    Some stakeholders continue to voice concerns about the performance of customer-sited photovoltaic (PV) systems, particularly because these systems typically receive financial support through ratepayer- or publicly-funded programs. Although much remains to be understood about the extent and specific causes of poor PV system performance, several studies of the larger programs and markets have shed some light on the issue. An evaluation of the California Energy Commission (CEC)'s Emerging Renewables Program, for example, found that 7% of systems, in a sample of 95, had lower-than-expected power output due to shading or soiling (KEMA 2005). About 3% of a larger sample of 140 systems were not operating at all or were operating well below expected output, due to failed equipment, faulty installation workmanship, and/or a lack of basic maintenance. In a recent evaluation of the other statewide PV incentive program in California, the Self-Generation Incentive Program, 9 of 52 projects sampled were found to have annual capacity factors less than 14.5%, although reasons for these low capacity factors generally were not identified (Itron 2005). Studies of PV systems in Germany and Japan, the two largest PV markets worldwide, have also revealed some performance problems associated with issues such as shading, equipment and installation defects, inverter failure, and deviations from module manufacturers' specifications (Otani et al. 2004, Jahn & Nasse 2004). Although owners of PV systems have an inherent incentive to ensure that their systems perform well, many homeowners and building operators may lack the necessary information and expertise to carry out this task effectively. Given this barrier, and the responsibility of PV incentive programs to ensure that public funds are prudently spent, these programs should (and often do) play a critical role in promoting PV system performance. Performance-based incentives (PBIs), which are based on actual energy production

  4. Optimal Photovoltaic System Sizing of a Hybrid Diesel/PV System

    Directory of Open Access Journals (Sweden)

    Ahmed Belhamadia

    2017-03-01

    Full Text Available This paper presents a cost analysis study of a hybrid diesel and Photovoltaic (PV system in Kuala Terengganu, Malaysia. It first presents the climate conditions of the city followed by the load profile of a 2MVA network; the system was evaluated as a standalone system. Diesel generator rating was considered such that it follows ISO 8528. The maximum size of the PV system was selected such that its penetration would not exceed 25%. Several sizes were considered but the 400kWp system was found to be the most cost efficient. Cost estimation was done using Hybrid Optimization Model for Electric Renewable (HOMER. Based on the simulation results, the climate conditions and the NEC 960, the numbers of the maximum and minimum series modules were suggested as well as the maximum number of the parallel strings.

  5. Simulation Model developed for a Small-Scale PV-System in a Distribution Network

    DEFF Research Database (Denmark)

    Koch-Ciobotaru, C.; Mihet-Popa, Lucian; Isleifsson, Fridrik Rafn

    2012-01-01

    This paper presents a PV panel simulation model using the single-diode four-parameter model based on data sheet values. The model was implemented first in MATLAB/Simulink, and the results have been compared with the data sheet values and characteristics of the PV panels in standard test conditions...... and implemented in PowerFactory to study load flow, steady-state voltage stability and dynamic behavior of a distributed power system....

  6. A cross-sectional study of stand-alone percutaneous coronary intervention in a Nigerian cardiac catheterization laboratory.

    Science.gov (United States)

    Johnson, Adeyemi; Falase, Bode; Ajose, Ifeoluwa; Onabowale, Yemi

    2014-01-16

    There is a paucity of diagnostic and therapeutic facilities in Nigeria to confirm coronary artery disease and offer appropriate interventional therapy. There is now a private cardiac catheterization laboratory in Lagos but as there are no sustained Open Heart Surgery programmes, percutaneous coronary interventions are currently being performed without surgical backup. This study was designed to assess results of stand-alone percutaneous coronary intervention (PCI) as currently practiced in Lagos, Nigeria. This cross-sectional study was conducted between July 2009 and July 2012. The study included all patients that underwent PCI in Lagos. Data was extracted from a prospectively maintained database. Coronary artery disease was confirmed in 80 (52.6%) of 152 Nigerians referred with a diagnosis of Ischaemic Heart Disease. There were 53 males (66.2%) and 27 females (33.8%). The average age was 60.3 +/-9.6 years and average euroscore was 4.5 +/-3.1. Of the 80 patients, 77 (96.3%) had significant stenoses and were candidates for revascularization. Distribution of significant stenoses was one in 32 patients (41.5%), two in 11 patients (14.3%), three in 19 patients (24.7%), four in 13 patients (16.9%) and five in 2 patients (2.6%). PCI was performed in 48 (62.3%) of the patients eligible for revascularization as the coronary anatomy in the remaining patients was not suitable for PCI. The indication for PCI was for myocardial infarction or unstable angina in 39 patients (81.2%). PCI was performed with PTCA plus stenting in 41 patients (85.4%) and with PTCA alone in 7 patients (14.6%) with good angiographic results. Overall 29 of the 48 patients (60.4%) had complete revascularization of significant stenoses. Complications of PCI were bleeding that required blood transfusion in 1 patient (2.1%), minor femoral haematomas in 2 patients (4.2%), and a major adverse clinical event in 1 patient (2.1%). A stand-alone PCI programme has been developed in Lagos, Nigeria. Both elective

  7. Integrated application of combined cooling, heating and power poly-generation PV radiant panel system of zero energy buildings

    Science.gov (United States)

    Yin, Baoquan

    2018-02-01

    A new type of combined cooling, heating and power of photovoltaic radiant panel (PV/R) module was proposed, and applied in the zero energy buildings in this paper. The energy system of this building is composed of PV/R module, low temperature difference terminal, energy storage, multi-source heat pump, energy balance control system. Radiant panel is attached on the backside of the PV module for cooling the PV, which is called PV/R module. During the daytime, the PV module was cooled down with the radiant panel, as the temperature coefficient influence, the power efficiency was increased by 8% to 14%, the radiant panel solar heat collecting efficiency was about 45%. Through the nocturnal radiant cooling, the PV/R cooling capacity could be 50 W/m2. For the multifunction energy device, the system shows the versatility during the heating, cooling and power used of building utilization all year round.

  8. Dynamic modelling of a PV pumping system with special consideration on water demand

    International Nuclear Information System (INIS)

    Campana, Pietro Elia; Li, Hailong; Yan, Jinyue

    2013-01-01

    Highlights: ► Evaluation of water demand and solar energy is essential for PV pumping system. ► The design for a PV water pumping system has been optimized based on dynamic simulations. ► It is important to conduct dynamic simulations to check the matching between water demand and water supply. ► AC pump driven by the fixed PV array is the most cost-effective solution. - Abstract: The exploitation of solar energy in remote areas through photovoltaic (PV) systems is an attractive solution for water pumping for irrigation systems. The design of a photovoltaic water pumping system (PVWPS) strictly depends on the estimation of the crop water requirements and land use since the water demand varies during the watering season and the solar irradiation changes time by time. It is of significance to conduct dynamic simulations in order to achieve the successful and optimal design. The aim of this paper is to develop a dynamic modelling tool for the design of a of photovoltaic water pumping system by combining the models of the water demand, the solar PV power and the pumping system, which can be used to validate the design procedure in terms of matching between water demand and water supply. Both alternate current (AC) and direct current (DC) pumps and both fixed and two-axis tracking PV array were analyzed. The tool has been applied in a case study. Results show that it has the ability to do rapid design and optimization of PV water pumping system by reducing the power peak and selecting the proper devices from both technical and economic viewpoints. Among the different alternatives considered in this study, the AC fixed system represented the best cost effective solution

  9. The Research on Second-Order ADRC Algorithm of Using Wind Turbine Virtual Inertia to Participate in Primary Frequency Regulation in a Small Stand-Alone Microgrid

    Directory of Open Access Journals (Sweden)

    Wang Yi

    2018-01-01

    Full Text Available In order to improve the transient stability of frequency in a small stand-alone microgrid (SSM, this paper takes a SSM composed of a direct-drive permanent magnet synchronous generator (D-PMSG and a micro gas turbine (MGT as the background and uses wind turbine generator (WTG virtual inertia (VI to participate in the primary (short-term system frequency regulation. First of all, this paper constructs a grid-connected model composed of a WTG and a MGT, analyzes the WTG virtual inertia frequency regulation mechanism, and explains the principle of proportional-differentiation (PD virtual inertia control (VIC and its shortcomings. Secondly, the paper introduces the structure principle of n-order active disturbance rejection control (ADRC and deduces the design process of second-order ADRC-VIC. Finally, through the simulation and experimental verification, comparing the frequency perturbation of without-VIC, PD-VIC, and ADRC-VIC, it is concluded that PD-VIC and ADRC-VIC both can use the WTG virtual inertia to participate in the primary frequency regulation. The frequency regulation effect of ADRC-VIC is better than PD-VIC, ADRC-VIC can extend the rotor speed recovery time and avoid overshoot, and its frequency fluctuation amplitude and settling time are obviously improved, and ADRC-VIC can effectively avoid the overshoot phenomenon of the MGT output power.

  10. A Single-Phase Multilevel PV Generation System with an Improved Ripple Correlation Control MPPT Algorithm

    Directory of Open Access Journals (Sweden)

    Manel Hammami

    2017-12-01

    Full Text Available The implementation of maximum power point tracking (MPPT schemes by the ripple correlation control (RCC algorithm is presented in this paper. A reference is made to single-phase single-stage multilevel photovoltaic (PV generation systems, when the inverter input variables (PV voltage and PV current have multiple low-frequency (ripple harmonics. The harmonic analysis is carried out with reference to a multilevel configuration consisting of an H-bridge inverter and level doubling network (LDN cell, leading to the multilevel inverter having double the output voltage levels as compared to the basic H-bridge inverter topology (i.e., five levels vs. three levels. The LDN cell is basically a half-bridge fed by a floating capacitor, with self-balancing voltage capability. The multilevel configuration introduces additional PV voltage and current low-frequency harmonics, perturbing the basic implementation of the RCC scheme (based on the second harmonic component, leading to malfunctioning. The proposed RCC algorithm employs the PV current and voltage harmonics at a specific frequency for the estimation of the voltage derivative of power dP/dV (or dI/dV, driving the PV operating point toward the maximum power point (MPP in a faster and more precise manner. The steady-state and transient performances of the proposed RCC-MPPT schemes have been preliminarily tested and compared using MATLAB/Simulink. Results have been verified by experimental tests considering the whole multilevel PV generation system, including real PV modules, multilevel insulated-gate bipolar transistor (IGBT inverters, and utility grids.

  11. Development of a Laser-Powered Dielectric Structure-Based Accelerator as a Stand-Alone Particle Source

    International Nuclear Information System (INIS)

    Yoder, R. B.; Travish, G.; Arab, E. R.; Fong, D.; Hoyer, Z.; Lacroix, U. H.; Vartanian, N.; Rosenzweig, J. B.

    2010-01-01

    An experimental program to develop and build a dielectric-based slab-symmetric structure (the micro-accelerator platform, or MAP) for generating and accelerating low-energy electrons is underway at UCLA and Manhattanville College. This optical acceleration structure is effectively a resonant cavity powered by a side-coupled laser, and has applications as a radiation source for medicine or industry. We present recent experimental and computational results on the accelerator, and progress toward its incorporation into a self-contained particle source. Such a particle source would incorporate a micron-scale electron emitter and a non-relativistic capture region to enable self-injection into the synchronous field within the accelerator. A prototype of the accelerator itself has been constructed from candidate dielectric materials using micromanufacturing techniques; the current status of the testing program is described. A novel electron emitter incorporating pyroelectric crystals with field-enhancing tips has been demonstrated to produce steady currents; the results are dependent on tip geometry, and appear suitable for injection into a microstructure. Extension of the MAP concept to non-relativistic velocities, as in the stand-alone source, requires a tapered structure that gives rise to numerous complications including beam defocusing and manufacturing challenges; approaches for addressing these complications are mentioned.

  12. Performance test of a grid-tied PV system to power a split air conditioner system in Surabaya

    Science.gov (United States)

    Tarigan, E.

    2017-11-01

    Air conditioner for cooling air is one of the major needs for those who live in hot climate area such as Indonesia. This work presents the performance test of a grid-tied PV system to power air conditioner under a hot tropical climate in Surabaya, Indonesia. A 800 WP grid-tied photovoltaic (PV) system was used, and its performance was tested to power a 0.5 pk of split air conditioner system. It was found that about 3.5 kWh daily energy was consumed by the tested air conditioner system, and about 80% it could be supplied from the PV system. While the other 20% was supplied by the grid during periods of low solar irradiation, 440 Wh of energy was fed into the grid during operation out of office hours. By using the grid-tied PV system, the energy production by PV system did not need to match the consumption of the air conditioner. However, a larger capacity of PV system would mean that a higher percentage of the load would be covered by PV system.

  13. A Low Cost Wireless Data Acquisition System for a Remote Photovoltaic (PV Water Pumping System

    Directory of Open Access Journals (Sweden)

    Ammar Mahjoubi

    2011-01-01

    Full Text Available This paper presents the design and development of a 16F877 microcontroller-based wireless data acquisition system and a study of the feasibility of different existing methodologies linked to field data acquisition from remote photovoltaic (PV water pumping systems. Various existing data transmission techniques were studied, especially satellite, radio, Global System for Mobile Communication (GSM and General Packet Radio Service (GPRS. The system’s hardware and software and an application to test its performance are described. The system will be used for reading, storing and analyzing information from several PV water pumping stations situated in remote areas in the arid region of the south of Tunisia. The remote communications are based on the GSM network and, in particular, on the Short text Message Service (SMS. With this integrated system, we can compile a complete database of the different parameters related to the PV water pumping systems of Tunisia. This data could be made available to interested parties over the Internet.

  14. New topology of multiple-input single-output PV system for DC load applications

    Directory of Open Access Journals (Sweden)

    Mohsen M. ELhagry

    2016-12-01

    Full Text Available Improving PV system structure and maximizing the output power of a PV system has drawn many researchers attention nowadays. A proposed multi-input single-output PV system is proposed in this paper. The system consists of multiple PV modules; each module feeds a DC–DC converter. The outputs of the converters are tied together to form a DC voltage source. In order to minimize the output ripples of the converters, the control signal of each converter is time shifted from each other by a certain time interval depending on the number of converters used in the topology. In this study a battery is used as the main load, the load current used as the control variable. A fuzzy logic controller designed to modulate the operating point of the system to get the maximum power. The results show that the proposed system has very good response for various operating conditions of the PV system. In addition the output filter is minimized with excellent quality of the DC output voltage.

  15. Embodied energy analysis of photovoltaic (PV) system based on macro- and micro-level

    International Nuclear Information System (INIS)

    Nawaz, I.; Tiwari, G.N.

    2006-01-01

    In this paper the energy payback time and CO 2 emissions of photovoltaic (PV) system have been analyzed. The embodied energy for production of PV module based on single crystal silicon, as well as for the manufacturing of other system components have been computed at macro- and micro-level assuming irradiation of 800-1200 W/m 2 in different climatic zones in India for inclined surface. The energy payback time with and without balance-of-system for open field and rooftop has been evaluated. It is found that the embodied energy at micro-level is significantly higher than embodied energy at macro-level. The effect of insolation, overall efficiency, lifetime of PV system on energy pay back time and CO 2 emissions have been studied with and without balance of system. A 1.2 kW p PV system of SIEMENS for mudhouse at IIT, Delhi based on macro- and micro-level has been evaluated. The CO 2 mitigation potential, the importance and role of PV system for sustainable development are also highlighted

  16. New current control based MPPT technique for single stage grid connected PV systems

    International Nuclear Information System (INIS)

    Jain, Sachin; Agarwal, Vivek

    2007-01-01

    This paper presents a new maximum power point tracking algorithm based on current control for a single stage grid connected photovoltaic system. The main advantage of this algorithm comes from its ability to predict the approximate amplitude of the reference current waveform or power that can be derived from the PV array with the help of an intermediate variable β. A variable step size for the change in reference amplitude during initial tracking helps in fast tracking. It is observed that if the reference current amplitude is greater than the array capacity, the system gets unstable (i.e. moves into the positive slope region of the p-v characteristics of the array). The proposed algorithm prevents the PV system from entering the positive slope region of the p-v characteristics. It is also capable of restoring stability if the system goes unstable due to a sudden environmental change. The proposed algorithm has been tested on a new single stage grid connected PV configuration recently developed by the authors to feed sinusoidal current into the grid. The system is operated in a continuous conduction mode to realize advantages such as low device current stress, high efficiency and low EMI. A fast MPPT tracker with single stage inverter topology operating in CCM makes the overall system highly efficient. Specific cases of the system, operating in just discontinuous current mode and discontinuous current mode and their relative merits and demerits are also discussed

  17. Automatic Supervision And Fault Detection In PV System By Wireless Sensors With Interfacing By Labview Program

    Directory of Open Access Journals (Sweden)

    Yousra M Abbas

    2015-08-01

    Full Text Available In this work a wireless monitoring system are designed for automatic detection localization fault in photovoltaic system. In order to avoid the use of modeling and simulation of the PV system we detected the fault by monitoring the output of each individual photovoltaic panel connected in the system by Arduino and transmit this data wirelessly to laptop then interface it by LabVIEW program which made comparison between this data and the measured data taking from reference module at the same condition. The proposed method is very simple but effective detecting and diagnosing the main faults of a PV system and was experimentally validated and has demonstrated its effectiveness in the detection and diagnosing of main faults present in the DC side of PV system.

  18. On the field performance of PV water pumping system in Libya

    International Nuclear Information System (INIS)

    Sbeta, M.; Sasi, S.

    2012-01-01

    This paper presents the measured performance of an experimental PV water pumping system of 1200Wp installed in the north-east of Libya. Both the monthly and hourly measured data of the system performance are presented and analised, and the over-all system efficiency has been calculated as monthly and daily averages. The monthly average output of the system has been estimated and compared with measured data. The economic analysis of the system has been carried out and the specific water discharge cost (SDC) has been determined, the obtained SDC was very competitive with the published SDC of the PV water pumping projects in some countries. The obtained results have demonstrated the technical and economic feasibility of using the PV systems for water pumping especially in the remote areas of high potential of solar insolation.(author)

  19. Design development and testing of a solar PV pump based drip system for orchards

    Energy Technology Data Exchange (ETDEWEB)

    Pande, P.C.; Singh, A.K.; Ansari, S.; Vyas, S.K.; Dave, B.K. [Central Arid Zone Research Inst., Jodhpur (India)

    2003-03-01

    A Solar Photovoltaic (PV) pump operated drip irrigation system has been designed and developed for growing orchards in arid region considering different design parameters like pumps size, water requirements, the diurnal variation in the pressure of the pump due to change in irradiance and pressure compensation in the drippers. The system comprising a PV pump with 900 W{sub p} PV array and 800 W dc motor-pump mono-block, microfilter, main and sub-mains and three open-able low-pressure compensating drippers on each plant was field tested. The emission uniformity was observed to be 92-94% with discharge of 3.8 l/h in the pressure range of 70-100 kPa provided by the pump and thus the system could irrigate some 1 ha area within 2 h. Based on the performance of the PV pump and the drip system, it was inferred that about 5 ha area of orchard could be covered. The projected benefit-cost ratio for growing pomegranate orchards with such a system was evaluated to be above 2 even with the costly PV pump and therefore the system was considered to be an appropriate technology for the development of arid region. (Author)

  20. Control and management of energy in a PV system equipped with batteries storage

    Directory of Open Access Journals (Sweden)

    Kamal Hirech

    2016-06-01

    Full Text Available In this paper we present a work concerning the conception, implementation and testing of a photovoltaic system that is equipped with a new concept of control and manage the energy in a PV system with a battery storage. The objective is to exploit the maximum of power using Hill climbing improved algorithm that considers optimal electrical characteristics of PV panels regardless of the system perturbation, to manage the energy between blocs of PV system in order to control the charge/discharge process and inject the energy surplus into the grid and also to estimate the state of charge with precision. Moreover, the system guarantees the acquisition and presentation of results on computer, supervision and so on. The results obtained show the robustness of the PV system, good control and protection of batteries under the maximum of energy provided by the PV panels. The state of charge estimation is evaluated by using measured parameters in real time; it shows an improvement of around 5% compared to the conventional technique.

  1. MPPT Schemes for PV System under Normal and Partial Shading Condition: A Review

    Directory of Open Access Journals (Sweden)

    Malik Sameeullah

    2016-08-01

    Full Text Available The photovoltaic system is one of the renewable energy device, which directly converts solar radiation into electricity. The I-V characteristics of PV system are nonlinear in nature and under variable Irradiance and temperature, PV system has a single operating point where the power output is maximum, known as Maximum Power Point (MPP and the point varies on changes in atmospheric conditions and electrical load. Maximum Power Point Tracker (MPPT is used to track MPP of solar PV system for maximum efficiency operation. The various MPPT techniques together with implementation are reported in literature. In order to choose the best technique based upon the requirements, comprehensive and comparative study should be available. The aim of this paper is to present a comprehensive review of various MPPT techniques for uniform insolation and partial shading conditions. Furthermore, the comparison of practically accepted and widely used techniques has been made based on features, such as control strategy, type of circuitry, number of control variables and cost. This review work provides a quick analysis and design help for PV systems. Article History: Received March 14, 2016; Received in revised form June 26th 2016; Accepted July 1st 2016; Available online How to Cite This Article: Sameeullah, M. and Swarup, A. (2016. MPPT Schemes for PV System under Normal and Partial Shading Condition: A Review. Int. Journal of Renewable Energy Development, 5(2, 79-94. http://dx.doi.org/10.14710/ijred.5.2.79-94 

  2. Model predictive control for power fluctuation supression in hybrid wind/PV/battery systems

    DEFF Research Database (Denmark)

    You, Shi; Liu, Zongyu; Zong, Yi

    2015-01-01

    A hybrid energy system, the combination of wind turbines, PV panels and battery storage with effective control mechanism, represents a promising solution to the power fluctuation problem when integrating renewable energy resources (RES) into conventional power systems. This paper proposes a model...... predictive control (MPC)-based algorithm for battery management in a hybrid wind/PV/battery system to suppress the short-term power fluctuation on the ‘minute’ scale. A case study with data collected from a practical hybrid system setup is used to demonstrate the effectiveness of the proposed algorithm...

  3. Power Electronic System for Multi-MW PV sites

    DEFF Research Database (Denmark)

    Paasch, Kasper

    .4%. A portable IV-scanning instrument for the fast long term characterization of solar panels was developed as part of the project. Each second a sweep of the IV-characteristics of a solar panel is performed and the result stored for later analysis. The instrument is based on an active load, is optimized...... a distance of 160 m. In parallel a string based inverter configuration was established with solar panels at the same locations. An analysis of irradiation data recorded during the test period showed that non-uniform irradiance due to moving clouds is expected to influence the PV plants for less than 4...... MPPT. The analysis is based on a comparative investigation of non-uniform irradiation events caused by moving clouds during a period of one year. A set-up for the long term recording of data from the 2.1 MW Danfoss Solar Park in Nordborg (DK) and the 62 kW PV plant at the University of Southern Denmark...

  4. Core Abilities Evaluation Index System Exploration and Empirical Study on Distributed PV-Generation Projects

    Directory of Open Access Journals (Sweden)

    Lin He

    2017-12-01

    Full Text Available In line with the constraints of environmental problems and economic development, large-scale renewable-generation projects have been planned and constructed in recent years. In order to achieve sustainable power development and improve the power supply structure, China’s government has focused on distributed photovoltaic (PV generation projects due to their advantages of clean emission and local consumption. However, their unstable output power still brings a series of problems concerning reliability, investment income, and available substitution proportion to traditional power, and so on. Therefore, it is imperative to understand the competitive development abilities of distributed PV generation projects and measure them effectively. First, through various investigation methods such as literature reviews, feasibility report analysis and expert interviews, the factors that influence the core abilities of distributed PV-generation projects were explored based on the micro-grid structure. Then, with the indexed exploration results, the factors were classified into 6 dimensions, i.e., investment and earning ability, production and operation ability, power-grid coordination ability, energy-conservation and emission-reduction ability, sustainable development ability, and society-serving ability. Meanwhile, an evaluation index system for core abilities of distributed PV-generation project was constructed using all quantitative indicators. Third, for examining the availability of the evaluation index system, combination weighting and techniques for order preference by similarity to an ideal solution (TOPSIS methods were adopted to assess the practical distributed PV-generation projects. The case study results showed that installed capacity, local economy development, and grid-connected power quantity will influence the core abilities of distributed PV-generation project, obviously. The conclusions of the evaluation analysis on core abilities can

  5. Adult Degenerative Scoliosis with Spinal Stenosis Treated with Stand-Alone Cage via an Extreme Lateral Transpsoas Approach; a Case Report and Literature Review

    Directory of Open Access Journals (Sweden)

    Arvind von Keudell

    2015-04-01

    Full Text Available We report the case of a 73-year-old female with severe degenerative scoliosis and back and leg pain that wassuccessfully treated with stand- alone cages via an extreme lateral transpsoas approach. This patient had declinedopen surgery and instrumentation due to her advanced age concerns about potential side effects.

  6. Forecasting and observability: critical technologies for system operations with high PV penetration

    DEFF Research Database (Denmark)

    Alet, Pierre-Jean; Efthymiou, Venizelos; Graditi, Giorgio

    2016-01-01

    Forecasting and monitoring technologies for photovoltaics are required on different spatial and temporal scales by multiple actors, from the owners of PV systems to transmission system operators. In this paper the Grid integration working group of the European Technology and Innovation Platform...... – Photovoltaics (ETIP PV) reviews the different use cases for these technologies, their current status, and the need for future developments. Power system operations require a real-time view of PV production for managing power reserves and for feeding shortterm forecasts. They also require forecasts on all...... timescales from the short (for dispatching purposes), where statistical models work best, to the very long (for infrastructure planning), where physics-based models are more accurate. Power system regulations are driving the development of these techniques. This application also provides a good basis...

  7. Capacity Value of PV and Wind Generation in the NV Energy System

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Shuai; Diao, Ruisheng; Samaan, Nader A.; Etingov, Pavel V.

    2014-03-21

    Calculation of photovoltaic (PV) and wind power capacity values is important for estimating additional load that can be served by new PV or wind installations in the electrical power system. It also is the basis for assigning capacity credit payments in systems with markets. Because of variability in solar and wind resources, PV and wind generation contribute to power system resource adequacy differently from conventional generation. Many different approaches to calculating PV and wind generation capacity values have been used by utilities and transmission operators. Using the NV Energy system as a study case, this report applies peak-period capacity factor (PPCF) and effective load carrying capability (ELCC) methods to calculate capacity values for renewable energy sources. We show the connection between the PPCF and ELCC methods in the process of deriving a simplified approach that approximates the ELCC method. This simplified approach does not require generation fleet data and provides the theoretical basis for a quick check on capacity value results of PV and wind generation. The diminishing return of capacity benefit as renewable generation increases is conveniently explained using the simplified capacity value approach.

  8. 3D simulation of complex shading affecting PV systems taking benefit from the power of graphics cards developed for the video game industry

    OpenAIRE

    Robledo, Jesus; Leloux, Jonathan; Lorenzo, Eduardo

    2014-01-01

    Shading reduces the power output of a photovoltaic (PV) system. The design engineering of PV systems requires modeling and evaluating shading losses. Some PV systems are affected by complex shading scenes whose resulting PV energy losses are very difficult to evaluate with current modeling tools. Several specialized PV design and simulation software include the possibility to evaluate shading losses. They generally possess a Graphical User Interface (GUI) through which the user can draw a 3D ...

  9. Modeling and Control of DC/DC Boost Converter using K-Factor Control for MPPT of Solar PV System

    DEFF Research Database (Denmark)

    Vangari, Adithya; Haribabu, Divyanagalakshmi; Sakamuri, Jayachandra N.

    2015-01-01

    is presented. Design of the passive elements of the boost converter as per the system specifications is also illustrated. The performance of the proposed K factor control method is verified with the simulations for MPPT on solar PV system at different atmospheric conditions. A new circuit based model for solar......This paper is focused on the design of a controller for the DC/DC boost converter using K factor control, which is based on modified PI control method, for maximum power point tracking (MPPT) of solar PV system. A mathematical model for boost converter based on small signal averaging approach...... PV array, which includes the effect of solar insolation and temperature on PV array output, for the application in power system transient simulations, is also presented. The performance of the PV array model is verified with simulations at different atmospheric conditions. A 160W PV module from BP...

  10. A methodology for optimal sizing of autonomous hybrid PV/wind system

    International Nuclear Information System (INIS)

    Diaf, S.; Diaf, D.; Belhamel, M.; Haddadi, M.; Louche, A.

    2007-01-01

    The present paper presents a methodology to perform the optimal sizing of an autonomous hybrid PV/wind system. The methodology aims at finding the configuration, among a set of systems components, which meets the desired system reliability requirements, with the lowest value of levelized cost of energy. Modelling a hybrid PV/wind system is considered as the first step in the optimal sizing procedure. In this paper, more accurate mathematical models for characterizing PV module, wind generator and battery are proposed. The second step consists to optimize the sizing of a system according to the loss of power supply probability (LPSP) and the levelized cost of energy (LCE) concepts. Considering various types and capacities of system devices, the configurations, which can meet the desired system reliability, are obtained by changing the type and size of the devices systems. The configuration with the lowest LCE gives the optimal choice. Applying this method to an assumed PV/wind hybrid system to be installed at Corsica Island, the simulation results show that the optimal configuration, which meet the desired system reliability requirements (LPSP=0) with the lowest LCE, is obtained for a system comprising a 125 W photovoltaic module, one wind generator (600 W) and storage batteries (using 253 Ah). On the other hand, the device system choice plays an important role in cost reduction as well as in energy production

  11. Technical model for optimising PV/diesel/battery hybrid power systems

    CSIR Research Space (South Africa)

    Tazvinga, Henerica

    2010-08-31

    Full Text Available A solar-based power supply system, such as a photovoltaic (PV)-diesel-battery system, is a particularly attractive option for decentralised power supply in southern Africa where solar radiation is ubiquitous in most countries. Such systems can make...

  12. The role of PV electricity generation in fully renewable energy supply systems

    International Nuclear Information System (INIS)

    Lehmann, H.; Peter, S.

    2004-01-01

    A sustainable energy supply will be based on renewable energies and it must use available resources efficiently. Earlier or later the energy supply will rely completely on renewable sources. A solar energy system that provides a reliable energy supply throughout the year includes the consistent use of local renewable energy sources (e.g. PV) wherever possible. Using Japan as a example it was shown that the vision of a full renewable energy supply, even with high shares of domestic sources is possible. Detailed simulations of such a system show that the PV systems play an important role delivering electricity at peak demand times. (authors)

  13. Determination of Duty Cycle for Energy Storage Systems in a PV Smoothing Application

    Energy Technology Data Exchange (ETDEWEB)

    Schoenwald, David A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ellison, James [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-04-01

    This report supplements the document, "Protocol for Uniformly Measuring and Expressing the Performance of Energy Storage Systems," issued in a revised version in April 2016 (see [4]), which will include the photovoltaic (PV) smoothing application for an energy storage system (ESS). This report provides the background and documentation associated with the determination of a duty cycle for an ESS operated in a PV smoothing application for the purpose of measuring and expressing ESS performance in accordance with the ESS performance protocol. ACKNOWLEDGEMENTS The authors gratefully acknowledge the support of Dr. Imre Gyuk, program manager for the DOE Energy Storage Systems Program. The authors would also like to express their appreciation to all the stakeholders who participated as members of the PV Smoothing Subgroup. Without their thoughtful input and recommendations, the definitions, metrics, and duty cycle provided in this report would not have been possible. A complete listing of members of the PV Smoothing Subgroup appears in the first chapter of this report. Special recognition should go to the staffs at Pacific Northwest National Laboratory (PNNL) and Sandia National Laboratories (SNL) in collaborating on this effort. In particular, Mr. David Conover and Dr. Vish Viswanathan of PNNL and Dr. Summer Ferreira of SNL were especially helpful in their suggestions for the determination of a duty cycle for the PV Smoothing application.

  14. Concentrating PV/T Hybrid System for Simultaneous Electricity and Usable Heat Generation: A Review

    Directory of Open Access Journals (Sweden)

    Longzhou Zhang

    2012-01-01

    Full Text Available Photovoltaic (PV power generation is one of the attractive choices for efficient utilization of solar energy. Considering that the efficiency and cost of PV cells cannot be significantly improved in near future, a relatively cheap concentrator to replace part of the expensive solar cells could be used. The photovoltaic thermal hybrid system (PV/T, combining active cooling with thermal electricity and providing both electricity and usable heat, can enhance the total efficiency of the system with reduced cell area. The effect of nonuniform light distribution and the heat dissipation on the performance of concentrating PV/T was discussed. Total utilization of solar light by spectral beam splitting technology was also introduced. In the last part, we proposed an integrated compound parabolic collector (CPC plate with low precision solar tracking, ensuring effective collection of solar light with a significantly lowered cost. With the combination of beam splitting of solar spectrum, use of film solar cell, and active liquid cooling, efficient and full spectrum conversion of solar light to electricity and heat, in a low cost way, might be realized. The paper may offer a general guide to those who are interested in the development of low cost concentrating PV/T hybrid system.

  15. Investigation of Synergy Between Electrochemical Capacitors, Flywheels, and Batteries in Hybrid Energy Storage for PV Systems

    International Nuclear Information System (INIS)

    Miller, John; Sibley Lewis, B.; Wohlgemuth, John

    1999-01-01

    This report describes the results of a study that investigated the synergy between electrochemical capacitors (ECs) and flywheels, in combination with each other and with batteries, as energy storage subsystems in photovoltaic (PV) systems. EC and flywheel technologies are described and the potential advantages and disadvantages of each in PV energy storage subsystems are discussed. Seven applications for PV energy storage subsystems are described along with the potential market for each of these applications. A spreadsheet model, which used the net present value method, was used to analyze and compare the costs over time of various system configurations based on flywheel models. It appears that a synergistic relationship exists between ECS and flywheels. Further investigation is recommended to quantify the performance and economic tradeoffs of this synergy and its effect on overall system costs

  16. Investigation of Synergy Between Electrochemical Capacitors, Flywheels, and Batteries in Hybrid Energy Storage for PV Systems

    Energy Technology Data Exchange (ETDEWEB)

    Miller, John; Sibley, Lewis, B.; Wohlgemuth, John

    1999-06-01

    This report describes the results of a study that investigated the synergy between electrochemical capacitors (ECs) and flywheels, in combination with each other and with batteries, as energy storage subsystems in photovoltaic (PV) systems. EC and flywheel technologies are described and the potential advantages and disadvantages of each in PV energy storage subsystems are discussed. Seven applications for PV energy storage subsystems are described along with the potential market for each of these applications. A spreadsheet model, which used the net present value method, was used to analyze and compare the costs over time of various system configurations based on flywheel models. It appears that a synergistic relationship exists between ECS and flywheels. Further investigation is recommended to quantify the performance and economic tradeoffs of this synergy and its effect on overall system costs.

  17. Adaptive Harmonic Compensation in Residential Distribution Grid by Roof-Top PV Systems

    DEFF Research Database (Denmark)

    Zangeneh Bighash, Esmaeil; Sadeghzadeh, Seyed Mohammad; Ebrahimzadeh, Esmaeil

    2018-01-01

    Fourier Transform (SDFT) algorithm and then individually compensate the measured harmonics by the proposed adaptive harmonic compensator. In the proposed approach, a current reference is separately determined for compensating each harmonic component. Then, a specific amount of additional current capacity...... grid- connected roof-top PV inverters in residential distribution grid can be an opportunity to engage these systems in the power quality issues as custom power devices. By implementing a proper control for roof-top PV inverters, these systems may in addition to inject the fundamental current......, additionally act like a virtual harmonic resistance and dedicate their additional current capacity to compensate the harmonics of residential distribution grid. In this paper, each roof-top PV system is a grid harmonic supervisor, where it continually measures the PCC voltage harmonics by Sliding Discrete...

  18. Concept of large scale PV-WT-PSH energy sources coupled with the national power system

    Directory of Open Access Journals (Sweden)

    Jurasz Jakub

    2017-01-01

    Full Text Available Intermittent/non-dispatchable energy sources are characterized by a significant variation of their energy yield over time. In majority of cases their role in energy systems is marginalized. However, even in Poland which is strongly dedicated to its hard and brown coal fired power plants, the wind generation in terms of installed capacity starts to play a significant role. This paper briefly introduces a concept of wind (WT and solar (PV powered pumped storage hydroelectricity (PSH which seems to be a viable option for solving the problem of the variable nature of PV and WT generation. Additionally we summarize the results of our so far conducted research on the integration of variable renewable energy sources (VRES to the energy systems and present conclusions which strictly refer to the prospects of large scale PV-WT-PSH operating as a part of the polish energy system.

  19. Comparison of four MPPT techniques for PV systems

    Energy Technology Data Exchange (ETDEWEB)

    Atik, L., E-mail: lotfi.atik@univ-usto.dz; Ternifi, Z. T. [University of science and technology of Oran, USTO, LDDE, Oran (Algeria); Université de Lorraine, LMOPS, EA 4423, 57070 Metz (France); Petit, P.; Sawicki, J. P.; Aillerie, M., E-mail: aillerie@metz.supelec.fr [Université de Lorraine, LMOPS, EA 4423, 57070 Metz (France); CentraleSupélec, LMOPS, 57070 Metz (France); Bachir, G. [University of science and technology of Oran, USTO, LDDE, Oran (Algeria)

    2016-07-25

    The working behavior of a module / PV array is non-linear and highly dependent on working conditions. As a given condition, there is only one point at which the level of available power at its output is maximum. This point varies with time, enlightenment and temperature. To ensure optimum operation, the use of MPPT control allows us to extract the maximum power. This paper presents a comparative study of four widely-adopted MPPT algorithms, such as Perturb and Observe, Incremental Conductance, Measurements of the variation of the open circuit voltage or of the short-circuit current. Their performance is evaluated using, for all these techniques. In particular, this study compares the behaviors of each technique in presence of solar irradiation variations and temperature fluctuations. These MPPT techniques will be compared using the Matlab / Simulink tool.

  20. Comparison of four MPPT techniques for PV systems

    Science.gov (United States)

    Atik, L.; Petit, P.; Sawicki, J. P.; Ternifi, Z. T.; Bachir, G.; Aillerie, M.

    2016-07-01

    The working behavior of a module / PV array is non-linear and highly dependent on working conditions. As a given condition, there is only one point at which the level of available power at its output is maximum. This point varies with time, enlightenment and temperature. To ensure optimum operation, the use of MPPT control allows us to extract the maximum power. This paper presents a comparative study of four widely-adopted MPPT algorithms, such as Perturb and Observe, Incremental Conductance, Measurements of the variation of the open circuit voltage or of the short-circuit current. Their performance is evaluated using, for all these techniques. In particular, this study compares the behaviors of each technique in presence of solar irradiation variations and temperature fluctuations. These MPPT techniques will be compared using the Matlab / Simulink tool.

  1. Design And Simulation Of A PV System With Battery Storage Using Bidirectional DC-DC Converter Using Matlab Simulink

    Directory of Open Access Journals (Sweden)

    Mirza Mursalin Iqbal

    2017-07-01

    Full Text Available PV Photovoltaic systems are one of the most renowned renewable green and clean sources of energy where power is generated from sunlight converting into electricity by the use of PV solar cells. Unlike fossil fuels solar energy has great environmental advantages as they have no harmful emissions during power generation. In this paper a PV system with battery storage using bidirectional DC-DC converter has been designed and simulated on MATLAB Simulink. The simulation outcomes verify the PV systems performance under standard testing conditions.

  2. Characteristics of low-priced solar PV systems in the U.S.

    Energy Technology Data Exchange (ETDEWEB)

    Nemet, Gregory F.; O’Shaughnessy, Eric; Wiser, Ryan; Darghouth, Naïm; Barbose, Galen; Gillingham, Ken; Rai, Varun

    2017-02-01

    Despite impressive declines in average prices, there is wide dispersion in the prices of U.S. solar photovoltaic (PV) systems; prices span more than a factor of four. What are the characteristics of the systems with low-prices? Using detailed characteristics of 42,611 small-scale (<15 kW) PV systems installed in 15 U.S. states during 2013, we identify the most important factors that make a system likely to be low-priced (LP). Comparing LP and non-LP systems, we find statistically significant differences in nearly all characteristics for which we have data. Logit and probit model results robustly indicate that LP systems are associated with: markets with few active installers; experienced installers; customer ownership; large systems; retrofits; and thin-film, low-efficiency, and Chinese modules. We also find significant differences across states, with LP systems much more likely to occur in some states, such as Arizona, New Jersey, and New Mexico, and less likely in others, such as California. Our focus on the left tail of the price distribution provides implications for policy that are distinct from recent studies of mean prices. While those studies find that PV subsidies increase mean prices, we find that subsidies also generate LP systems. PV subsidies appear to simultaneously shift and broaden the price distribution. Much of this broadening occurs in a particular location, northern California.

  3. Design of Energy Storage Control Strategy to Improve the PV System Power Quality

    DEFF Research Database (Denmark)

    Lei, Mingyu; Yang, Zilong; Wang, Yibo

    2016-01-01

    Random fluctuation of PV power is becoming a more and more serious problem affecting the power quality and stability of grid as the PV penetration keeps increasing recent years. Aiming at this problem, this paper proposed a control strategy of energy storage system based on Model Predictive Control...... (MPC). By the continuous optimizing of MPC, we can obtain the system parameters accurately, and then calculate the energy storage power. At the same time, this control took state of charge (SOC) and other parameters into account to ensure the health and stability of the energy storage units. Finally......, simulation results proved the proposed control strategy had good performance and robustness....

  4. Droop Control with Improved Disturbance Adaption for PV System with Two Power Conversion Stages

    DEFF Research Database (Denmark)

    Liu, Hongpeng; Loh, Poh Chiang; Wang, Xiongfei

    2016-01-01

    issues, an improved droop scheme for a two-stage PV system has been developed in the paper. The developed scheme uses the same control structure in both grid-connected and islanded modes, which together with properly tuned synchronizers, allows mode transfer to be seamlessly triggered. Moreover...... with no or insufficient storage for cushioning climatic changes. In addition, most droop-controlled literatures have assumed a single dc-ac inverter with its input dc source fixed. Front-end dc-dc converter added to a two-stage photovoltaic (PV) system has therefore usually been ignored. To address these unresolved...

  5. Analysis of PV system's values beyond energy - by country and stakeholder

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Polo, A.; Hass, R.; Suna, D.

    2008-03-15

    This report for the International Energy Agency (IEA) made by Task 10 of the Photovoltaic Power Systems (PVPS) programme and PV-Up-Scale analyses, identifies, evaluates and quantifies the major values and benefits of urban scale photovoltaics (PV) based on country and stakeholder specifics. The mission of the Photovoltaic Power Systems Programme is to enhance the international collaboration efforts which accelerate the development and deployment of photovoltaic solar energy. The values evaluated and quantified in this report are categorised under the following groups: Avoiding fossil fuels, environmental benefits, benefits for electric utilities, industry development and employment benefits and the customer's individual benefits. The relevance of PV to meeting peak demand is discussed, as are the benefits for architects and building developers.

  6. Online model-based fault detection for grid connected PV systems monitoring

    KAUST Repository

    Harrou, Fouzi

    2017-12-14

    This paper presents an efficient fault detection approach to monitor the direct current (DC) side of photovoltaic (PV) systems. The key contribution of this work is combining both single diode model (SDM) flexibility and the cumulative sum (CUSUM) chart efficiency to detect incipient faults. In fact, unknown electrical parameters of SDM are firstly identified using an efficient heuristic algorithm, named Artificial Bee Colony algorithm. Then, based on the identified parameters, a simulation model is built and validated using a co-simulation between Matlab/Simulink and PSIM. Next, the peak power (Pmpp) residuals of the entire PV array are generated based on both real measured and simulated Pmpp values. Residuals are used as the input for the CUSUM scheme to detect potential faults. We validate the effectiveness of this approach using practical data from an actual 20 MWp grid-connected PV system located in the province of Adrar, Algeria.

  7. Public Response to Residential Grid-Tied PV Systems in Colorado: A Qualitative Market Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Farhar, Barbara C. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Buhrmann, Jan [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    1998-07-01

    The early adopters of residential grid-tied photovoltaics (PV) have complex motivations to pay today's costs, including altruistic, environmental, and financial reasons. Focused interviews were conducted with a self-selected purposive sample interested in purchasing 2-kW or 3-kW PV systems with an installed cost of $8,000 to $12,000. The sample tended to be men or married couples ranging in age from their early thirties to their mid-eighties; professionals, managers, or small business owners; relatively financially secure, with experience with energy efficiency and renewable energy. Product attributes they preferred were net metering, warranties, guarantees, utility financing, maintenance, an option to own or lease, a battery option, and an aesthetically pleasing system. Potential PV customers needed more information before making a purchase decision.

  8. Conception and realization of a PV system provided with a sun tracker operating at dual axis

    Directory of Open Access Journals (Sweden)

    Khalil Kassmi

    2016-06-01

    Full Text Available In this paper, we present the conception, the realization and the experimentation of  a photovoltaic (PV system provided with a sun tracker reliable and low cost operating at dual axis. The tracker's role is to orient the PV generator, whose weight may reach 9 Kg, perpendicular to the sun with very good accuracy. This tracking  based on the use of four LDR sensors, which detect the intensity of light scattered by the sun a processing unit, from  command and control (UTCC, which manages all of the sun tracking tasks (the end detection of parcours, regulation of the power supplied by the PV panels (Command MPPT, ... . The results obtained show a significant improvement of the energy produced, compared to conventional PV installations where generators are fixed and oriented south at a  tilt 45°. During a day of operation, improvement could reach 41% and consumption of the tracking does not exceed 0.55% of the energy production produced by the PV generator (an improvement of 5 % compared to existing trackers.

  9. Performance of natural curaua fiber-reinforced polyester composites under 7.62 mm bullet impact as a stand-alone ballistic armor

    Directory of Open Access Journals (Sweden)

    Fábio de Oliveira Braga

    2017-10-01

    Full Text Available A multilayered armor system (MAS is intended to personal protection against high kinetic energy ammunition. MAS layers are composed of materials such as a front ceramic and a back composite that must show both high impact resistance and low weight, usually conflicting characteristics. Synthetic fiber fabrics, such as Kevlar™ and Dyneema™, are the favorite materials to back the front ceramic, due to their high strength, high modulus and relatively low weight. Recently, composites reinforced with natural fibers have been considered as MAS second layer owing to their good performance associated with other advantages as being cheaper and environmentally friendly. Among the natural fibers, those extracted from the leaves of the Ananas erectifolius plant, known as curaua, stand out due to its exceptional high strength and high modulus. Thus, the objective of the present work is to evaluate the performance of curaua fiber-reinforced polyester composites subjected to ballistic impact of high energy 7.62 mm ammunition. Composites reinforced with 0, 10, 20 and 30 vol.% of curaua fibers were produced and stand-alone tested as armor target to evaluate the absorbed energy. Analysis of variance (Anova and Tukey's honest significant difference test (HSD made it possible to compare the results to Kevlar™ laminates. Among the tested materials, the 30 vol.% fiber composites were found to be the best alternative to Kevlar™. Keywords: Composite, Natural fiber, Curaua fiber, Ballistic test

  10. CANGS DB: a stand-alone web-based database tool for processing, managing and analyzing 454 data in biodiversity studies.

    Science.gov (United States)

    Pandey, Ram Vinay; Nolte, Viola; Boenigk, Jens; Schlötterer, Christian

    2011-06-30

    Next generation sequencing (NGS) is widely used in metagenomic and transcriptomic analyses in biodiversity. The ease of data generation provided by NGS platforms has allowed researchers to perform these analyses on their particular study systems. In particular the 454 platform has become the preferred choice for PCR amplicon based biodiversity surveys because it generates the longest sequence reads. Nevertheless, the handling and organization of massive amounts of sequencing data poses a major problem for the research community, particularly when multiple researchers are involved in data acquisition and analysis. An integrated and user-friendly tool, which performs quality control, read trimming, PCR primer removal, and data organization is desperately needed, therefore, to make data interpretation fast and manageable. We developed CANGS DB (Cleaning and Analyzing Next Generation Sequences DataBase) a flexible, stand alone and user-friendly integrated database tool. CANGS DB is specifically designed to organize and manage the massive amount of sequencing data arising from various NGS projects. CANGS DB also provides an intuitive user interface for sequence trimming and quality control, taxonomy analysis and rarefaction analysis. Our database tool can be easily adapted to handle multiple sequencing projects in parallel with different sample information, amplicon sizes, primer sequences, and quality thresholds, which makes this software especially useful for non-bioinformaticians. Furthermore, CANGS DB is especially suited for projects where multiple users need to access the data. CANGS DB is available at http://code.google.com/p/cangsdb/. CANGS DB provides a simple and user-friendly solution to process, store and analyze 454 sequencing data. Being a local database that is accessible through a user-friendly interface, CANGS DB provides the perfect tool for collaborative amplicon based biodiversity surveys without requiring prior bioinformatics skills.

  11. CANGS DB: a stand-alone web-based database tool for processing, managing and analyzing 454 data in biodiversity studies

    Directory of Open Access Journals (Sweden)

    Schlötterer Christian

    2011-06-01

    Full Text Available Abstract Background Next generation sequencing (NGS is widely used in metagenomic and transcriptomic analyses in biodiversity. The ease of data generation provided by NGS platforms has allowed researchers to perform these analyses on their particular study systems. In particular the 454 platform has become the preferred choice for PCR amplicon based biodiversity surveys because it generates the longest sequence reads. Nevertheless, the handling and organization of massive amounts of sequencing data poses a major problem for the research community, particularly when multiple researchers are involved in data acquisition and analysis. An integrated and user-friendly tool, which performs quality control, read trimming, PCR primer removal, and data organization is desperately needed, therefore, to make data interpretation fast and manageable. Findings We developed CANGS DB (Cleaning and Analyzing Next Generation Sequences DataBase a flexible, stand alone and user-friendly integrated database tool. CANGS DB is specifically designed to organize and manage the massive amount of sequencing data arising from various NGS projects. CANGS DB also provides an intuitive user interface for sequence trimming and quality control, taxonomy analysis and rarefaction analysis. Our database tool can be easily adapted to handle multiple sequencing projects in parallel with different sample information, amplicon sizes, primer sequences, and quality thresholds, which makes this software especially useful for non-bioinformaticians. Furthermore, CANGS DB is especially suited for projects where multiple users need to access the data. CANGS DB is available at http://code.google.com/p/cangsdb/. Conclusion CANGS DB provides a simple and user-friendly solution to process, store and analyze 454 sequencing data. Being a local database that is accessible through a user-friendly interface, CANGS DB provides the perfect tool for collaborative amplicon based biodiversity surveys

  12. Power Generation Potential and Cost of a Roof Top Solar PV System in Kathmandu, Nepal

    Science.gov (United States)

    Sanjel, N.; Zhand, A.

    2017-12-01

    The paper presents a comparative study of the 3 most used solar PV module technologies in Nepal, which are Si-mono-crystalline, Si-poly-crystalline and Si-amorphous. The aim of the paper is to present and discuss the recorded Global Solar Radiation, received in the Kathmandu valley by three different, Si-mono-crystalline, Si-poly-crystalline and Si-amorphous calibrated solar cell pyranometers and to propose the best-suited solar PV module technology for roof top solar PV systems inside the Kathmandu valley. Data recorded over the course of seven months, thus covering most of the seasonal meteorological conditions determining Kathmandu valley's global solar radiation reception are presented. The results indicate that the Si-amorphous pyranometer captured 1.56% more global solar radiation than the Si-mono-crystalline and 18.4% more than Si-poly-crystalline pyranometer over the course of seven months. Among the three pyranometer technologies the maximum and minimum cell temperature was measured by the Si-mono-crystalline pyranometer. Following the technical data and discussion, an economical analysis, using the versatile software tool PVSYST V5.01is used to calculate the life cycle costs of a 1kW roof top solar PV RAPS system, with battery storage, and a 1kW roof top solar PV grid connected system with no energy storage facility, through simulations, using average recorded global solar radiation data for the KTM valley and investigated market values for each solar PV module and peripheral equipment costs.

  13. Post-processing in cardiovascular computed tomography. Performance of a client server solution versus a stand-alone solution

    International Nuclear Information System (INIS)

    Luecke, C.; Foldyna, B.; Andres, C.; Grothoff, M.; Nitzsche, S.; Gutberlet, M.; Lehmkuhl, L.; Boehmer-Lasthaus, S.

    2014-01-01

    Purpose: To compare the performance of server-based (CSS) versus stand-alone post-processing software (ES) for the evaluation of cardiovascular CT examinations (cvCT) and to determine the crucial steps. Data of 40 patients (20 patients for coronary artery evaluation and 20 patients prior to transcatheter aortic valve implantation [TAVI]) were evaluated by 5 radiologists with CSS and ES. Data acquisition was performed using a dual-source 128-row CT unit (SOMATOM Definition Flash, Siemens, Erlangen, Germany) and a 64-row CT unit (Brilliance 64, Philips, Hamburg, Germany). The following workflow was evaluated: Data loading, aorta and coronary segmentation, curved multiplanar reconstruction (cMPR) and 3 D volume rendering technique (3D-VRT), measuring of coronary artery stenosis and planimetry of the aortic annulus. The time requirement and subjective quality for the workflow were evaluated. The coronary arteries as well as the TAVI data could be evaluated significantly faster with CSS (5.5 ± 2.9 min and 8.2 ± 4.0 min, respectively) than with ES (13.9 ± 5.2 min and 15.2 ± 10.9 min, respectively, p = 0.01). Segmentation of the aorta (CSS: 1.9 ± 2.0 min, ES: 3.7 ± 3.3 min), generating cMPR of coronaries (CSS: 0.5 ± 0.2 min, ES: 5.1 ± 2.6 min), aorta and iliac vessels (CSS: 0.5 ± 0.4 min and 0.4 ± 0.4 min, respectively, ES: 1.6 ± 0.7 min and 2.8 ± 3 min, respectively) could be performed significantly faster with CSS than with ES with higher quality of cMPR, measuring of coronary stenosis and 3D-VRT (p < 0.05). Evaluation of cvCT can be accomplished significantly faster and better with CSS than with ES. The segmentation remains the most time-consuming workflow step, so optimization of segmentation algorithms could improve performance even further.

  14. Post-processing in cardiovascular computed tomography: performance of a client server solution versus a stand-alone solution.

    Science.gov (United States)

    Lücke, C; Foldyna, B; Andres, C; Boehmer-Lasthaus, S; Grothoff, M; Nitzsche, S; Gutberlet, M; Lehmkuhl, L

    2014-12-01

    To compare the performance of server-based (CSS) versus stand-alone post-processing software (ES) for the evaluation of cardiovascular CT examinations (cvCT) and to determine the crucial steps. Data of 40 patients (20 patients for coronary artery evaluation and 20 patients prior to transcatheter aortic valve implantation [TAVI]) were evaluated by 5 radiologists with CSS and ES. Data acquisition was performed using a dual-source 128-row CT unit (SOMATOM Definition Flash, Siemens, Erlangen, Germany) and a 64-row CT unit (Brilliance 64, Philips, Hamburg, Germany). The following workflow was evaluated: Data loading, aorta and coronary segmentation, curved multiplanar reconstruction (cMPR) and 3 D volume rendering technique (3D-VRT), measuring of coronary artery stenosis and planimetry of the aortic annulus. The time requirement and subjective quality for the workflow were evaluated. The coronary arteries as well as the TAVI data could be evaluated significantly faster with CSS (5.5  ±  2.9  min and 8.2  ±  4.0  min, respectively) than with ES (13.9  ±  5.2  min and 15.2  ±  10.9  min, respectively, p ≤  0.01). Segmentation of the aorta (CSS: 1.9 ±  2.0  min, ES: 3.7  ±  3.3  min), generating cMPR of coronaries (CSS: 0.5  ±  0.2  min, ES: 5.1  ±  2.6  min), aorta and iliac vessels (CSS: 0.5  ±  0.4  min and 0.4  ±  0.4  min, respectively, ES: 1.6  ±  0.7  min and 2.8  ±  3  min, respectively) could be performed significantly faster with CSS than with ES with higher quality of cMPR, measuring of coronary stenosis and 3D-VRT (p < 0.05). Evaluation of cvCT can be accomplished significantly faster and better with CSS than with ES.  The segmentation remains the most time-consuming workflow step, so optimization of segmentation algorithms could improve performance even further. © Georg Thieme Verlag KG Stuttgart · New York.

  15. What Factors Affect the Prices of Low-Priced U.S. Solar PV Systems?

    Energy Technology Data Exchange (ETDEWEB)

    Nemet, Gregory F. [Univ. of Wisconsin, Madison, WI (United States); Mercator Research Inst. on Global Commons and Climate Change, Berlin (Germany); O' Shaughnessy, Eric [National Renewable Energy Lab. (NREL), Golden, CO (United States); Wiser, Ryan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Darghouth, Naïm R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Barbose, Galen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Gillingham, Ken [Yale Univ., New Haven, CT (United States); Rai, Varun [Univ. of Texas, Austin, TX (United States)

    2016-08-01

    The price of solar PV systems has declined rapidly, yet there are some much lower-priced systems than others. This study explores the factors leading some systems to be so much lower priced than others. Using a data set of 42,611 residential-scale PV systems installed in the U.S. in 2013, we use quantile regressions to estimate the importance of factors affecting the installed prices for low-priced (LP) systems (those at the 10th percentile) in comparison to median-priced systems. We find that the value of solar to consumers–a variable that accounts for subsidies, electric rates, and PV generation levels–is associated with lower prices for LP systems but higher prices for median priced systems. Conversely, systems installed in new home construction are associated with lower prices at the median but higher prices for LP. Other variables have larger cost-reducing effects on LP than on median priced systems: systems installed in Arizona and Florida, as well as commercial and thin film systems. In contrast, the following have a smaller effect on prices for LP systems than median priced systems: tracking systems, self-installations, systems installed in Massachusetts, the system size, and installer experience. These results highlight the complex factors at play that lead to LP systems and shed light into how such LP systems can come about.

  16. Grid Connected Solar PV System with SEPIC Converter Compared with Parallel Boost Converter Based MPPT

    Directory of Open Access Journals (Sweden)

    T. Ajith Bosco Raj

    2014-01-01

    Full Text Available The main objective of this work is to study the behaviour of the solar PV systems and model the efficient Grid-connected solar power system. The DC-DC MPPT circuit using chaotic pulse width modulation has been designed to track maximum power from solar PV module. The conversion efficiency of the proposed MPPT system is increased when CPWM is used as a control scheme. This paper also proposes a simplified multilevel (seven level inverter for a grid-connected photovoltaic system. The primary goal of these systems is to increase the energy injected to the grid by keeping track of the maximum power point of the panel, by reducing the switching frequency, and by providing high reliability. The maximum power has been tracked experimentally. It is compared with parallel boost converter. Also this model is based on mathematical equations and is described through an equivalent circuit including a PV source with MPPT, a diode, a series resistor, a shunt resistor, and dual boost converter with active snubber circuit. This model can extract PV power and boost by using dual boost converter with active snubber. By using this method the overall system efficiency is improved thereby reducing the switching losses and cost.

  17. Market assessment of photovoltaic power systems for agricultural applications in the Philippines

    Science.gov (United States)

    Cabraal, R. A.; Delasanta, D.; Burrill, G.

    1981-01-01

    The market potential in the Philippines for stand alone photovoltaic (P/V) systems in agriculture was assessed. Applications include: irrigation, postharvest operation, food and fiber processing and storage, and livestock and fisheries operations. Power and energy use profiles for many applications as well as assessments of business, government and financial climate for P/V sales are described. Many characteristics of the Philippine agriculture and energy sector favorably influence the use of P/V systems. However, serious and significant barriers prevent achieving the technically feasible, cost competitive market for P/V systems in the agricultural sector. The reason for the small market is the limited availability capital for financing P/V systems. It is suggested that innovative financing schemes and promotional campaigns should be devised.

  18. REopt Improves the Operations of Alcatraz's Solar PV-Battery-Diesel Hybrid System

    Energy Technology Data Exchange (ETDEWEB)

    Olis, Daniel R [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Walker, H. A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Van Geet, Otto D [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-07

    This poster identifies operations improvement strategies for a photovoltaic (PV)-battery-diesel hybrid system at the National Park Service's Alcatraz Island using NREL's REopt analysis tool. The current 'cycle charging' strategy results in significant curtailing of energy production from the PV array, requiring excessive diesel use, while also incurring high wear on batteries without benefit of improved efficiency. A simple 'load following' strategy results in near optimal operating cost reduction.

  19. A simple, rigorous method for sizing the array of a PV hybrid system

    Energy Technology Data Exchange (ETDEWEB)

    Ross, M.M.D. [RER Renewable Energy Research, Montreal, PQ (Canada)

    2007-07-01

    Although computerized simulation tools are often used to size photovoltaic (PV) arrays, they can often hide errors that are difficult to correct. This paper provided details of a simplified sizing method for PV arrays. The method was used to indicate whether a PV-hybrid system was more cost-effective than a genset-battery system, as well as to identify the most cost-effective array sizing. Monthly solar data in tabular form was used. Array costs and genset costs were combined to determine overall cost. The per unit cost of generating electricity with the PV array was calculated. The per unit cost of generating electricity with the genset was then calculated. The array was then sized so that if another unit of PV array capacity was added, the fraction of the additional unit's output would be wasted over the course of the year. The estimate was then adjusted to account for financing costs such as debt service payments. The present value of the future stream of debt payments was added to the equity portion of the installed cost of the array and divided by the size of the array. The useful energy produced by each unit of array capacity over the project lifetime was determined by multiplying the project duration by the annual output of a unit of array capacity reduced by losses in the battery, wiring, and any other power conversion equipment. A case study of a PV installation at a house in Manitoba was provided to demonstrate the method. 4 refs., 2 tabs., 1 fig.

  20. PLL Based Energy Efficient PV System with Fuzzy Logic Based Power Tracker for Smart Grid Applications.

    Science.gov (United States)

    Rohini, G; Jamuna, V

    This work aims at improving the dynamic performance of the available photovoltaic (PV) system and maximizing the power obtained from it by the use of cascaded converters with intelligent control techniques. Fuzzy logic based maximum power point technique is embedded on the first conversion stage to obtain the maximum power from the available PV array. The cascading of second converter is needed to maintain the terminal voltage at grid potential. The soft-switching region of three-stage converter is increased with the proposed phase-locked loop based control strategy. The proposed strategy leads to reduction in the ripple content, rating of components, and switching losses. The PV array is mathematically modeled and the system is simulated and the results are analyzed. The performance of the system is compared with the existing maximum power point tracking algorithms. The authors have endeavored to accomplish maximum power and improved reliability for the same insolation of the PV system. Hardware results of the system are also discussed to prove the validity of the simulation results.

  1. An automated model for rooftop PV systems assessment in ArcGIS using LIDAR

    Directory of Open Access Journals (Sweden)

    Mesude Bayrakci Boz

    2015-08-01

    Full Text Available As photovoltaic (PV systems have become less expensive, building rooftops have come to be attractive for local power production. Identifying rooftops suitable for solar energy systems over large geographic areas is needed for cities to obtain more accurate assessments of production potential and likely patterns of development. This paper presents a new method for extracting roof segments and locating suitable areas for PV systems using Light Detection and Ranging (LIDAR data and building footprints. Rooftop segments are created using seven slope (tilt, ve aspect (azimuth classes and 6 different building types. Moreover, direct beam shading caused by nearby objects and the surrounding terrain is taken into account on a monthly basis. Finally, the method is implemented as an ArcGIS model in ModelBuilder and a tool is created. In order to show its validity, the method is applied to city of Philadelphia, PA, USA with the criteria of slope, aspect, shading and area used to locate suitable areas for PV system installation. The results show that 33.7% of the buildings footprints areas and 48.6% of the rooftop segments identi ed is suitable for PV systems. Overall, this study provides a replicable model using commercial software that is capable of extracting individual roof segments with more detailed criteria across an urban area.

  2. Investigation of power values of PV rooftop systems based on heat gain reduction

    Science.gov (United States)

    Chenvidhya, Tanokkorn; Seapan, Manit; Parinya, Panom; Wiengmoon, Buntoon; Chenvidhya, Dhirayut; Songprakorp, Roongrojana; Limsakul, Chamnan; Sangpongsanont, Yaowanee; Tannil, Nittaya

    2015-09-01

    PV rooftop system can generally be installed to produce electricity for the domestic house, office, small enterprise as well as factory. Such a system has direct useful for reducing peak load, meanwhile it also provides shaded area on the roof and hence the heat gain into the building is reduced. This study aims to investigate the shading effect on reduction of heat transfer into the building. The 49 kWp of PV rooftop system has been installed on the deck of the office building located in the middle of Thailand where the latitude of 14 ° above the equator. The estimation of heat gain into the building due to the solar irradiation throughout a day for one year has been carried out, before and after the installation of the PV rooftop system. Then the Newton's law of cooling is applied to calculate the heat gain. The calculation and the measurement of the heat reduction are compared. Finally, the indirect benefit of the PV rooftop system installed is evaluated in terms of power value.

  3. PLL Based Energy Efficient PV System with Fuzzy Logic Based Power Tracker for Smart Grid Applications

    Directory of Open Access Journals (Sweden)

    G. Rohini

    2016-01-01

    Full Text Available This work aims at improving the dynamic performance of the available photovoltaic (PV system and maximizing the power obtained from it by the use of cascaded converters with intelligent control techniques. Fuzzy logic based maximum power point technique is embedded on the first conversion stage to obtain the maximum power from the available PV array. The cascading of second converter is needed to maintain the terminal voltage at grid potential. The soft-switching region of three-stage converter is increased with the proposed phase-locked loop based control strategy. The proposed strategy leads to reduction in the ripple content, rating of components, and switching losses. The PV array is mathematically modeled and the system is simulated and the results are analyzed. The performance of the system is compared with the existing maximum power point tracking algorithms. The authors have endeavored to accomplish maximum power and improved reliability for the same insolation of the PV system. Hardware results of the system are also discussed to prove the validity of the simulation results.

  4. Potential and cost-effectiveness of off-grid PV systems in Indonesia - An evaluation on a provincial level

    NARCIS (Netherlands)

    Veldhuis, A.J.; Reinders, Angelina H.M.E.

    2014-01-01

    In this study we estimate the potential of off-grid PV systems in Indonesia at a provincial level as a follow-up of a study on the potential of grid-connected PV systems in Indonesia which we executed in 2012 [1]. For this study we use an adapted methodology leading to cumulative numbers for the

  5. Solar PV Project Financing: Regulatory and Legislative Challenges for Third-Party PPA System Owners

    Energy Technology Data Exchange (ETDEWEB)

    Kollins, K.; Speer, B.; Cory, K.

    2009-11-01

    Residential and commercial end users of electricity who want to generate electricity using on-site solar photovoltaic (PV) systems face challenging initial and O&M costs. The third-party ownership power purchase agreement (PPA) finance model addresses these and other challenges. It allows developers to build and own PV systems on customers? properties and sell power back to customers. However, third-party electricity sales commonly face five regulatory challenges. The first three challenges involve legislative or regulatory definitions of electric utilities, power generation equipment, and providers of electric services. These definitions may compel third-party owners of solar PV systems to comply with regulations that may be cost prohibitive. Third-party owners face an additional challenge if they may not net meter, a practice that provides significant financial incentive to owning solar PV systems. Finally, municipalities and cooperatives worry about the regulatory implications of allowing an entity to sell electricity within their service territories. This paper summarizes these challenges, when they occur, and how they have been addressed in five states. This paper also presents alternative to the third-party ownership PPA finance model, including solar leases, contractual intermediaries, standardized contract language, federal investment tax credits, clean renewable energy bonds, and waived monopoly powers.

  6. An experimental study on energy generation with a photovoltaic (PV)-solar thermal hybrid system

    International Nuclear Information System (INIS)

    Erdil, Erzat; Ilkan, Mustafa; Egelioglu, Fuat

    2008-01-01

    A hybrid system, composed of a photovoltaic (PV) module and a solar thermal collector is constructed and tested for energy collection at a geographic location of Cyprus. Normally, it is required to install a PV system occupying an area of about 10 m 2 in order to produce electrical energy; 7 kWh/day, required by a typical household. In this experimental study, we used only two PV modules of area approximately 0.6 m 2 (i.e., 1.3x0.47 m 2 ) each. PV modules absorb a considerable amount of solar radiation that generate undesirable heat. This thermal energy, however, may be utilized in water pre-heating applications. The proposed hybrid system produces about 2.8 kWh thermal energy daily. Various attachments that are placed over the hybrid modules lead to a total of 11.5% loss in electrical energy generation. This loss, however, represents only 1% of the 7 kWh energy that is consumed by a typical household in northern Cyprus. The pay-back period for the modification is less than 2 years. The low investment cost and the relatively short pay-back period make this hybrid system economically attractive

  7. Analysis of concentrating PV-T systems for the commercial/industrial sector. Volume III. Technical issues and design guidance

    Energy Technology Data Exchange (ETDEWEB)

    Schwinkendorf, W.E.

    1984-09-01

    This report provide appropriate guidance for addressing the major technical issues associated with the design and installation of a photovoltaic-thermal (PV-T) system. Nomographs are presented for developing preliminary sizing and costing, and issues associated with specific components and the overall design of the electrical and mechanical system are discussed. SAND82-7157/2 presents a review of current PV-T technology and operating systems and a study of potential PV-T applications. Detailed PV-T system designs for three selected applications and the results of a trade-off study for these applications are presented in SAND82-7157/4. A summary of the major results of this entire study and conclusions concerning PV-T systems and applications is presented in SAND82-7157/1.

  8. Numerical investigation of heat pipe-based photovoltaic–thermoelectric generator (HP-PV/TEG) hybrid system

    International Nuclear Information System (INIS)

    Makki, Adham; Omer, Siddig; Su, Yuehong; Sabir, Hisham

    2016-01-01

    Highlights: • Integration of TE generators with a heat pipe-based PV module as a hybrid system is proposed. • Numerical transient modeling based on the energy balance equations of the system was performed. • Integration of TE generators with PV module aid operating the solar cells at a steady level in harsh conditions. - Abstract: Photovoltaic (PV) cells are able to absorb about 80% of the solar spectral irradiance, however, certain percentage accounts for electricity conversion depending on the cell technology employed. The remainder energy however, can elevate the silicon junction temperature in the PV encapsulation perilously, resulting in deteriorated performance. Temperature rise at the PV cell level is addressed as one of the most critical issues that can seriously degrade and shortens the life-time of the PV cells, hence thermal management of the PV module during operation is considered essential. Hybrid PV designs which are able to simultaneously generate electrical energy and utilize the waste heat have been proven to be the most promising solution. In this study, theoretical investigation of a hybrid system comprising of thermoelectric generator integration with a heat pipe-based Photovoltaic/Thermal (PV/T) absorber is proposed and evaluated. The system presented incorporates a PV panel for direct electricity generation, a heat pipe for excessive heat absorption from the PV cells and a thermoelectric generator (TEG) performing direct heat-to-electricity conversion. A mathematical model based on the energy balance within the system is developed to evaluate the performance of the hybrid integration and the improvements associated with the thermal management of PV cells. Results are presented in terms of the overall system efficiency compared to a conventional PV panel under identical operating conditions. The integration of TEG modules with PV cells in such way aid improving the performance of the PV cells in addition to utilizing the waste

  9. A Novel Design and Optimization Software for Autonomous PV/Wind/Battery Hybrid Power Systems

    Directory of Open Access Journals (Sweden)

    Ali M. Eltamaly

    2014-01-01

    Full Text Available This paper introduces a design and optimization computer simulation program for autonomous hybrid PV/wind/battery energy system. The main function of the new proposed computer program is to determine the optimum size of each component of the hybrid energy system for the lowest price of kWh generated and the best loss of load probability at highest reliability. This computer program uses the hourly wind speed, hourly radiation, and hourly load power with several numbers of wind turbine (WT and PV module types. The proposed computer program changes the penetration ratio of wind/PV with certain increments and calculates the required size of all components and the optimum battery size to get the predefined lowest acceptable probability. This computer program has been designed in flexible fashion that is not available in market available software like HOMER and RETScreen. Actual data for Saudi sites have been used with this computer program. The data obtained have been compared with these market available software. The comparison shows the superiority of this computer program in the optimal design of the autonomous PV/wind/battery hybrid system. The proposed computer program performed the optimal design steps in very short time and with accurate results. Many valuable results can be extracted from this computer program that can help researchers and decision makers.

  10. Closed Loop Fuzzy Logic Controlled PV Based Cascaded Boost Five-Level Inverter System

    Science.gov (United States)

    Revana, Guruswamy; Kota, Venkata Reddy

    2018-04-01

    Recent developments in intelligent control methods and power electronics have produced PV based DC to AC converters related to AC drives. Cascaded boost converter and inverter find their way in interconnecting PV and Induction Motor. This paper deals with digital simulation and implementation of closed loop controlled five-level inverter based Photo-Voltaic (PV) system. The objective of this work is to reduce the harmonics using Multi Level Inverter based system. The DC output from the PV panel is boosted using cascaded-boost-converters. The DC output of these cascaded boost converters is applied to the bridges of the cascaded inverter. The AC output voltage is obtained by the series cascading of the output voltage of the two inverters. The investigations are done with Induction motor load. Cascaded boost-converter is proposed in the present work to produce the required DC Voltage at the input of the bridge inverter. A simple FLC is applied to CBFLIIM system. The FLC is proposed to reduce the steady state error. The simulation results are compared with the hardware results. The results of the comparison are made to show the improvement in dynamic response in terms of settling time and steady state error. Design procedure and control strategy are presented in detail.

  11. Efficacy and Efficiency of Italian Energy Policy: The Case of PV Systems in Greenhouse Farms

    Directory of Open Access Journals (Sweden)

    Filippo Sgroi

    2014-06-01

    Full Text Available The production of energy from renewable sources is a form of energy production that has less impact on the environment than the traditional one. For the farmer this new form of production represents an opportunity, especially for the economic benefits that can produce, both in terms of the incentives provided by the public operator and for higher revenues, deriving from the sale of energy back to the grid and/or the savings generated by self-consumed energy, that help to increase the farmer’s income. In this paper, we analyzed a case study of a farm that has realized a grid-connected photovoltaic (PV system on a greenhouse. In particular, firstly the farm profitability has been estimated and subsequently, in order to assess the efficiency of the energy policy adopted by the Second Conto Energia in Italy, the minimum incentive tariff at which the entrepreneur has an economic advantage to realize a PV system has been determined. Results show that PV system relegates to a marginal role the cultivation of agricultural products compared to energy production and that government PV remuneration policies far outweigh the minimum threshold that makes the investment advantageous.

  12. Sustainable electricity generation by solar pv/diesel hybrid system without storage for off grids areas

    Science.gov (United States)

    Azoumah, Y.; Yamegueu, D.; Py, X.

    2012-02-01

    Access to energy is known as a key issue for poverty reduction. The electrification rate of sub Saharan countries is one of the lowest among the developing countries. However this part of the world has natural energy resources that could help raising its access to energy, then its economic development. An original "flexy energy" concept of hybrid solar pv/diesel/biofuel power plant, without battery storage, is developed in order to not only make access to energy possible for rural and peri-urban populations in Africa (by reducing the electricity generation cost) but also to make the electricity production sustainable in these areas. Some experimental results conducted on this concept prototype show that the sizing of a pv/diesel hybrid system by taking into account the solar radiation and the load/demand profile of a typical area may lead the diesel generator to operate near its optimal point (70-90 % of its nominal power). Results also show that for a reliability of a PV/diesel hybrid system, the rated power of the diesel generator should be equal to the peak load. By the way, it has been verified through this study that the functioning of a pv/Diesel hybrid system is efficient for higher load and higher solar radiation.

  13. Sustainable electricity generation by solar pv/diesel hybrid system without storage for off grids areas

    International Nuclear Information System (INIS)

    Azoumah, Y; Yamegueu, D; Py, X

    2012-01-01

    Access to energy is known as a key issue for poverty reduction. The electrification rate of sub Saharan countries is one of the lowest among the developing countries. However this part of the world has natural energy resources that could help raising its access to energy, then its economic development. An original 'flexy energy' concept of hybrid solar pv/diesel/biofuel power plant, without battery storage, is developed in order to not only make access to energy possible for rural and peri-urban populations in Africa (by reducing the electricity generation cost) but also to make the electricity production sustainable in these areas. Some experimental results conducted on this concept prototype show that the sizing of a pv/diesel hybrid system by taking into account the solar radiation and the load/demand profile of a typical area may lead the diesel generator to operate near its optimal point (70-90 % of its nominal power). Results also show that for a reliability of a PV/diesel hybrid system, the rated power of the diesel generator should be equal to the peak load. By the way, it has been verified through this study that the functioning of a pv/Diesel hybrid system is efficient for higher load and higher solar radiation.

  14. Control and Modulation Techniques for a Centralized PV Generation System Grid Connected via an Interleaved Inverter

    Directory of Open Access Journals (Sweden)

    Gianluca Brando

    2016-09-01

    Full Text Available In the context of grid connected photovoitaic (PV generation systems, there are two paramount aspects regarding the Maximum Power Point Tracking (MPPT of the photovoltaic units and the continuity of the service. The most diffused MPPT algorithms are based on either perturb and observe, or on an incremental conductance approach and need both PV current and voltage measurements. Several topology reconfigurable converters are also associated with the PV plants, guaranteeing fault-tolerant features. The generation continuity can also be assured by interleaved inverters, which keep the system operating at reduced maximum power in case of failure. In this paper, an evolution of a hysteresis based MPPT algorithm is presented, based on the measurement of only one voltage, together with a novel space vector modulation suitable for a two-channel three-phase grid connected interleaved inverter. The proposed MMPT algorithm and modulation technique are tested by means of several numerical analyses on a PV generation system of about 200 kW maximum power. The results testify the validity of the proposed strategies, showing good performance, even during a fault occurrence and in the presence of deep shading conditions.

  15. Closed Loop Fuzzy Logic Controlled PV Based Cascaded Boost Five-Level Inverter System

    Science.gov (United States)

    Revana, Guruswamy; Kota, Venkata Reddy

    2017-12-01

    Recent developments in intelligent control methods and power electronics have produced PV based DC to AC converters related to AC drives. Cascaded boost converter and inverter find their way in interconnecting PV and Induction Motor. This paper deals with digital simulation and implementation of closed loop controlled five-level inverter based Photo-Voltaic (PV) system. The objective of this work is to reduce the harmonics using Multi Level Inverter based system. The DC output from the PV panel is boosted using cascaded-boost-converters. The DC output of these cascaded boost converters is applied to the bridges of the cascaded inverter. The AC output voltage is obtained by the series cascading of the output voltage of the two inverters. The investigations are done with Induction motor load. Cascaded boost-converter is proposed in the present work to produce the required DC Voltage at the input of the bridge inverter. A simple FLC is applied to CBFLIIM system. The FLC is proposed to reduce the steady state error. The simulation results are compared with the hardware results. The results of the comparison are made to show the improvement in dynamic response in terms of settling time and steady state error. Design procedure and control strategy are presented in detail.

  16. Is Stand-Alone Anterior Lumbar Interbody Fusion a Safe and Efficacious Treatment for Isthmic Spondylolisthesis of L5-S1?

    OpenAIRE

    Viglione, Luke L.; Chamoli, Uphar; Diwan, Ashish D.

    2017-01-01

    Study Design: A systematic review. Objective: The objective of this study was to determine the safety and efficacy of stand-alone anterior lumbar interbody fusion (sa-ALIF) for the treatment of symptomatic isthmic spondylolisthesis of L5-S1 by assessing the level of available clinical and radiographic evidence. Methods: A systematic review utilizing Medline, Embase, and Scopus online databases was undertaken. Clinical, radiographic, and adverse outcome data were extracted for the relevant ist...

  17. Standing with electrical stimulation and splinting is no better than standing alone for management of ankle plantarflexion contractures in people with traumatic brain injury: a randomised trial

    Directory of Open Access Journals (Sweden)

    Joan Leung

    2014-12-01

    Full Text Available Question: Is a combination of standing, electrical stimulation and splinting more effective than standing alone for the management of ankle contractures after severe brain injury? Design: A multi-centre randomised trial with concealed allocation, assessor blinding and intention-to-treat analysis. Participants: Thirty-six adults with severe traumatic brain injury and ankle plantarflexion contractures. Intervention: All participants underwent a 6-week program. The experimental group received tilt table standing, electrical stimulation and ankle splinting. The control group received tilt table standing alone. Outcome measures: The primary outcome was passive ankle dorsiflexion with a 12 Nm torque. Secondary outcomes included: passive dorsiflexion with lower torques (3, 5, 7 and 9 Nm; spasticity; the walking item of the Functional Independence Measure; walking speed; global perceived effect of treatment; and perceived treatment credibility. Outcome measures were taken at baseline (Week 0, end of intervention (Week 6, and follow-up (Week 10. Results: The mean between-group differences (95% CI for passive ankle dorsiflexion at Week 6 and Week 10 were –3 degrees (–8 to 2 and –1 degrees (–6 to 4, respectively, in favour of the control group. There was a small mean reduction of 1 point in spasticity at Week 6 (95% CI 0.1 to 1.8 in favour of the experimental group, but this effect disappeared at Week 10. There were no differences for other secondary outcome measures except the physiotherapists’ perceived treatment credibility. Conclusion: Tilt table standing with electrical stimulation and splinting is not better than tilt table standing alone for the management of ankle contractures after severe brain injury. Trial registration: ACTRN12608000637347. [Leung J, Harvey LA, Moseley AM, Whiteside B, Simpson M, Stroud K (2014 Standing with electrical stimulation and splinting is no better than standing alone for management of ankle plantarflexion

  18. Intelligent Energy Management System for PV-Battery-based Microgrids in Future DC Homes

    Science.gov (United States)

    Chauhan, R. K.; Rajpurohit, B. S.; Gonzalez-Longatt, F. M.; Singh, S. N.

    2016-06-01

    This paper presents a novel intelligent energy management system (IEMS) for a DC microgrid connected to the public utility (PU), photovoltaic (PV) and multi-battery bank (BB). The control objectives of the proposed IEMS system are: (i) to ensure the load sharing (according to the source capacity) among sources, (ii) to reduce the power loss (high efficient) in the system, and (iii) to enhance the system reliability and power quality. The proposed IEMS is novel because it follows the ideal characteristics of the battery (with some assumptions) for the power sharing and the selection of the closest source to minimize the power losses. The IEMS allows continuous and accurate monitoring with intelligent control of distribution system operations such as battery bank energy storage (BBES) system, PV system and customer utilization of electric power. The proposed IEMS gives the better operational performance for operating conditions in terms of load sharing, loss minimization, and reliability enhancement of the DC microgrid.

  19. High-Penetration PV Deployment in the Arizona Public Service System, Phase 1 Update: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Hambrick, J.; Narang, D.

    2012-06-01

    In an effort to better understand the impacts of high penetrations of photovoltaic generators on distribution systems, Arizona Public Service and its partners have begun work on a multi-year project to develop the tools and knowledge base needed to safely and reliably integrate high penetrations of utility- and residential-scale photovoltaics (PV). Building upon the APS Community Power Project -- Flagstaff Pilot, this project will analyze the impact of PV on a representative feeder in northeast Flagstaff. To quantify and catalog the effects of the estimated 1.3 MW of PV that will be installed on the feeder (both smaller units at homes as well as large, centrally located systems), high-speed weather and electrical data acquisition systems and digital 'smart' meters are being designed and installed to facilitate monitoring and to build and validate comprehensive, high-resolution models of the distribution system. These models will be used to analyze the impacts of the PV on distribution circuit protection systems (including anti-islanding), predict voltage regulation and phase balance issues, and develop volt/var control schemes. This paper continues from a paper presented at the 2011 IEEE PVSC conference that introduces the project and describes some of the preliminary consideration, as well as project plans and early results. This paper gives a status update of the project and presents selected results from Phase 2 of the project. It discusses baseline feeder modeling, load allocation, data acquisition, utility-scale PV integration, preliminary model validation, and plans for future phases.

  20. Studies on battery storage requirement of PV fed wind-driven induction generators

    International Nuclear Information System (INIS)

    Rajan Singaravel, M.M.; Arul Daniel, S.

    2013-01-01

    Highlights: ► Sizing of battery storage for PV fed wind-driven IG system is taken up. ► Battery storage is also used to supply reactive power for wind-driven IG. ► Computation of LPSP by incorporating uncertainties of irradiation and wind speed. ► Sizing of hybrid power system components to ensure zero LPSP. ► Calculated storage size satisfied the constraints and improves battery life. - Abstract: Hybrid stand-alone renewable energy systems based on wind–solar resources are considered to be economically better and reliable than stand-alone systems with a single source. An isolated hybrid wind–solar system has been considered in this work, where the storage (battery bank) is necessary to supply the required reactive power for a wind-driven induction generator (IG) during the absence of power from a photovoltaic (PV) array. In such a scheme, to ensure zero Loss of Power Supply Probability (LPSP) and to improve battery bank life, a sizing procedure has been proposed with the incorporation of uncertainties in wind-speed and solar-irradiation level at the site of erection of the plant. Based on the proposed procedure, the size of hybrid power system components and storage capacity are determined. Storage capacity has been calculated for two different requirements. The first requirement of storage capacity is common to any hybrid scheme, which is; to supply both real and reactive power in the absence of wind and solar sources. The second requirement is to supply reactive power alone for the IG during the absence of photovoltaic power, which is unique to the hybrid scheme considered in this work. Storage capacity calculations for different conditions using the proposed approach, satisfies the constraints of maintaining zero LPSP and also improved cycle life of the battery bank

  1. Anterior cervical discectomy and fusion using a stand-alone polyetheretherketone cage packed with local autobone : assessment of bone fusion and subsidence.

    Science.gov (United States)

    Park, Jeong-Ill; Cho, Dae-Chul; Kim, Kyoung-Tae; Sung, Joo-Kyung

    2013-09-01

    It remains debatable whether cervical spine fusion cages should be filled with any kind of bone or bone substitute. Cortical and subcortical bone from the anterior and posterior osteophytes of the segment could be used to fill the cage. The purposes of the present study are to evaluate the clinical outcomes and radiological outcomes including bone fusion and subsidence that occurred after anterior cervical discectomy and fusion using a stand-alone cage packed with local autobone graft. Thirty-one patients who underwent anterior cervical fusion using a stand-alone polyetheretherketone (PEEK) cage packed with local autobone graft from July 2009 to december 2011 were enrolled in this study. Bone fusion was assessed by cervical plain radiographs and computed tomographic scan. Nonunion was evaluated according to the absence of bony bridge on computed tomographic scan. Subsidence was defined as a ≥2 mm decrease of the interbody height at the final follow-up compared to that measured at the immediate postoperative period. Subsidence was observed in 7 patients (22.6%). Of 7 patients with subsidence greater 2 mm, nonunion was developed in 3. Three patients with subsidence greater 2 mm were related with endplate damage during intraoperative endplate preparation. Solid bone fusion was achieved in 28 out of 31 patients (90.3%). With proper patient selection and careful endplate preparation, anterior cervical discectomy and fusion (ACDF) using a stand-alone PEEK cage packed with local autobone graft could be a good alternative to the standard ACDF techniques with plating.

  2. Enhanced Grey Wolf Optimizer based MPPT Algorithm of PV system under Partial Shaded Condition

    Directory of Open Access Journals (Sweden)

    Santhan Kumar Cherukuri

    2017-11-01

    Full Text Available Partial shading condition is one of the adverse phenomena which effects the power output of photovoltaic (PV systems due to inaccurate tracking of global maximum power point. Conventional Maximum Power Point Tracking (MPPT techniques like Perturb and Observe, Incremental Conductance and Hill Climbing can track the maximum power point effectively under uniform shaded condition, but fails under partial shaded condition. An attractive solution under partial shaded condition is application of meta-heuristic algorithms to operate at global maximum power point. Hence in this paper, an Enhanced Grey Wolf Optimizer (EGWO based maximum power point tracking algorithm is proposed to track the global maximum power point of PV system under partial shading condition. A Mathematical model of PV system is developed under partial shaded condition using single diode model and EGWO is applied to track global maximum power point. The proposed method is programmed in MATLAB environment and simulations are carried out on 4S and 2S2P PV configurations for dynamically changing shading patterns. The results of the proposed method are analyzed and compared with GWO and PSO algorithms. It is observed that proposed method is effective in tracking global maximum power point with more accuracy in less computation time compared to other methods. Article History: Received June 12nd 2017; Received in revised form August 13rd 2017; Accepted August 15th 2017; Available online How to Cite This Article: Kumar, C.H.S and Rao, R.S. (2017 Enhanced Grey Wolf Optimizer Based MPPT Algorithm of PV System Under Partial Shaded Condition. Int. Journal of Renewable Energy Development, 6(3, 203-212. https://doi.org/10.14710/ijred.6.3.203-212

  3. Energy and Cost Saving of a Photovoltaic-Phase Change Materials (PV-PCM System through Temperature Regulation and Performance Enhancement of Photovoltaics

    Directory of Open Access Journals (Sweden)

    Ahmad Hasan

    2014-03-01

    Full Text Available The current research seeks to maintain high photovoltaic (PV efficiency and increased operating PV life by maintaining them at a lower temperature. Solid-liquid phase change materials (PCM are integrated into PV panels to absorb excess heat by latent heat absorption mechanism and regulate PV temperature. Electrical and thermal energy efficiency analysis of PV-PCM systems is conducted to evaluate their effectiveness in two different climates. Finally costs incurred due to inclusion of PCM into PV system and the resulting benefits are discussed in this paper. The results show that such systems are financially viable in higher temperature and higher solar radiation environment.

  4. Performance analysis of ‘Perturb and Observe’ and ‘Incremental Conductance’ MPPT algorithms for PV system

    Science.gov (United States)

    Lodhi, Ehtisham; Lodhi, Zeeshan; Noman Shafqat, Rana; Chen, Fieda

    2017-07-01

    Photovoltaic (PV) system usually employed The Maximum power point tracking (MPPT) techniques for increasing its efficiency. The performance of the PV system perhaps boosts by controlling at its apex point of power, in this way maximal power can be given to load. The proficiency of a PV system usually depends upon irradiance, temperature and array architecture. PV array shows a non-linear style for V-I curve and maximal power point on V-P curve also varies with changing environmental conditions. MPPT methods grantees that a PV module is regulated at reference voltage and to produce entire usage of the maximal output power. This paper gives analysis between two widely employed Perturb and Observe (P&O) and Incremental Conductance (INC) MPPT techniques. Their performance is evaluated and compared through theoretical analysis and digital simulation on the basis of response time and efficiency under varying irradiance and temperature condition using Matlab/Simulink.

  5. Photovoltaic systems for the nature parks of Rio de Janeiro municipality; Sistemas fotovoltaicos para os parques municipais da cidade do Rio de Janeiro, RJ

    Energy Technology Data Exchange (ETDEWEB)

    Galdino, Marco Antonio; Silva, Patricia de Castro da [Centro de Pesquisas de Energia Eletrica (CEPEL), Rio de Janeiro, RJ (Brazil)], e-mails: marcoag@cepel.br, patricia@cepel.br; Masi, Monica di [Secretaria Municipal de Meio Ambiente da Cidade do Rio de Janeiro (SMAC/RJ), RJ (Brazil)], e-mail: monica.masi@smac.rio.rj.gov.br

    2010-07-01

    This paper presents the current status of the project run by the Municipality of Rio de Janeiro, though its Secretary for the Environment, aiming the implantation of photovoltaic (PV) systems for electrification of the Nature Parks of the City. Relevant characteristics of 6 parks, which are to receive first the PV systems, are discussed here, including Parks Prainha, Dois Irmaos, Chico Mendes, Marapendi and Bosque da Barra, as well as the PV systems to be installed in each park. The projects include stand-alone and grid-connected PV systems, and plans to install a total power of more than 60kWp of PV panels. This activity is considered innovative and a part of the preparation of the City for important international events of the coming years: World Cup 2014 and Olympic Games 2016. (author)

  6. Mitigating the Detrimental Impacts of Solar PV Penetration on Electric Power Transmission Systems

    Science.gov (United States)

    Prakash, Nitin

    At present, almost 70% of the electric energy in the United States is produced utilizing fossil fuels. Combustion of fossil fuels contributes CO 2 to the atmosphere, potentially exacerbating the impact on global warming. To make the electric power system (EPS) more sustainable for the future, there has been an emphasis on scaling up generation of electric energy from wind and solar resources. These resources are renewable in nature and have pollution free operation. Various states in the US have set up different goals for achieving certain amount of electrical energy to be produced from renewable resources. The Southwestern region of the United States receives significant solar radiation throughout the year. High solar radiation makes concentrated solar power and solar PV the most suitable means of renewable energy production in this region. However, the majority of the projects that are presently being developed are either residential or utility owned solar PV plants. This research explores the impact of significant PV penetration on the steady state voltage profile of the electric power transmission system. This study also identifies the impact of PV penetration on the dynamic response of the transmission system such as rotor angle stability, frequency response and voltage response after a contingency. The light load case of spring 2010 and the peak load case of summer 2018 have been considered for analyzing the impact of PV. If the impact is found to be detrimental to the normal operation of the EPS, mitigation measures have been devised and presented in the thesis. Commercially available software tools/packages such as PSLF, PSS/E, DSA Tools have been used to analyze the power network and validate the results.

  7. Design and evaluation of hybrid wind/PV/diesel power systems for Brazilian applications

    Energy Technology Data Exchange (ETDEWEB)

    McGowan, J.G.; Manwell, J.F.; Avelar, C. [Univ. of Massachusetts, Amherst, MA (United States); Warner, C. [National Renewable Energy Lab., Golden, CO (United States)

    1996-12-31

    This paper presents a summary of a study centered on the design and evaluation of hybrid wind/PV/diesel systems for remote locations in Brazil. The objective of this work was to evaluate high reliability hybrid power systems that have been designed for the lowest life cycle costs. The technical and economic analysis of the hybrid wind/PV/diesel systems was carried out using HYBRID2, a computational code developed at the University of Massachusetts in conjunction with the National Renewable Energy Laboratory (NREL). After a summary of a generalized design procedure for such systems based on the use of this code, a systematic parametric evaluation of a representative design case for a village power system in Brazil is presented. As summarized in the paper, the performance and economic effects of key design parameters are illustrated. 8 refs., 10 figs.

  8. An insight on advantage of hybrid sun–wind-tracking over sun-tracking PV system

    International Nuclear Information System (INIS)

    Rahimi, Masoud; Banybayat, Meisam; Tagheie, Yaghoub; Valeh-e-Sheyda, Peyvand

    2015-01-01

    Graphical abstract: Real photograph of hybrid sun–wind-tracking system. - Highlights: • Novel hybrid sun–wind-tracking system proposed to enhance PV cell performance. • The wind tracker can cool down the PV cell as sun-tracking system work. • The hybrid tracker achieved 7.4% increase in energy gain over the sun tracker. • The overall daily output energy gain was increased by 49.83% by using this system. - Abstract: This paper introduces the design and application of a novel hybrid sun–wind-tracking system. This hybrid system employs cooling effect of wind, besides the advantages of tracking sun for enhancing power output from examined hybrid photovoltaic cell. The principal experiment focuses on comparison between dual-axes sun-tracking and hybrid sun–wind-tracking photovoltaic (PV) panels. The deductions based on the research tests confirm that the overall daily output energy gain was increased by 49.83% compared with that of a fixed system. Moreover, an overall increase of about 7.4% in the output power was found for the hybrid sun–wind-tracking over the two-axis sun tracking system.

  9. Design, Simulation and Experimental Investigation of a Solar System Based on PV Panels and PVT Collectors

    Directory of Open Access Journals (Sweden)

    Annamaria Buonomano

    2016-06-01

    Full Text Available This paper presents numerical and experimental analyses aimed at evaluating the technical and economic feasibility of photovoltaic/thermal (PVT collectors. An experimental setup was purposely designed and constructed in order to compare the electrical performance of a PVT solar field with the one achieved by an identical solar field consisting of conventional photovoltaic (PV panels. The experimental analysis also aims at evaluating the potential advantages of PVT vs. PV in terms of enhancement of electrical efficiency and thermal energy production. The installed experimental set-up includes four flat polycrystalline silicon PV panels and four flat unglazed polycrystalline silicon PVT collectors. The total electrical power and area of the solar field are 2 kWe and 13 m2, respectively. The experimental set-up is currently installed at the company AV Project Ltd., located in Avellino (Italy. This study also analyzes the system from a numerical point of view, including a thermo-economic dynamic simulation model for the design and the assessment of energy performance and economic profitability of the solar systems consisting of glazed PVT and PV collectors. The experimental setup was modelled and partly simulated in TRNSYS environment. The simulation model was useful to analyze efficiencies and temperatures reached by such solar technologies, by taking into account the reference technology of PVTs (consisting of glazed collectors as well as to compare the numerical data obtained by dynamic simulations with the gathered experimental results for the PV technology. The numerical analysis shows that the PVT global efficiency is about 26%. Conversely, from the experimental point of view, the average thermal efficiency of PVT collectors is around 13% and the electrical efficiencies of both technologies are almost coincident and equal to 15%.

  10. A comprehensive techno-economic and power quality analysis of a remote PV-diesel system in Australia

    Directory of Open Access Journals (Sweden)

    Jamal Taskin

    2017-01-01

    Full Text Available Presently, the world is considering the integration of small, medium and large-scale PV systems into both urban and remote rural electricity networks. This sees a transition towards a 100% renewable energy based electricity supply from the current conventional fossil fuel based electricity supply. Australia has a significant electricity generation potential from solar PV resources which also encourages the uptake of PV-battery hybrid systems. Australian utilities operating in the isolated and remote areas are now seriously considering the integration of solar PV systems as a long-term solution to reduce costs and facilitate sustainable electricity generation. This would also defer expensive grid extension to supply electricity to these dispersed remote communities. This study aims to model and optimise a remote Australian PV-diesel system incorporated with high levels of PV penetration and battery storage and investigate the