Switching coordination of distributed dc-dc converters for highly efficient photovoltaic power plants

Science.gov (United States)

Agamy, Mohammed; Elasser, Ahmed; Sabate, Juan Antonio; Galbraith, Anthony William; Harfman Todorovic, Maja

2014-09-09

A distributed photovoltaic (PV) power plant includes a plurality of distributed dc-dc converters. The dc-dc converters are configured to switch in coordination with one another such that at least one dc-dc converter transfers power to a common dc-bus based upon the total system power available from one or more corresponding strings of PV modules. Due to the coordinated switching of the dc-dc converters, each dc-dc converter transferring power to the common dc-bus continues to operate within its optimal efficiency range as well as to optimize the maximum power point tracking in order to increase the energy yield of the PV power plant.

Modeling and sizing the coil in boost converters dedicated to photovoltaic sources

Science.gov (United States)

Atik, Lotfi; Fares, Mohammed Amine; Zaraket, Jean; Bachir, Ghalem; Aillerie, Michel

2018-05-01

The coil is a very important element in a wide range of power electrical systems as such as those used in converter or inverter dedicated to extract and to adapt the value and the shape of the intensity and the voltage delivered by renewable energy sources. Thus, knowing its behavior in converters is paramount to obtain a maximum conversion efficiency and reliability. In this context, this paper presents a global study of a DC/DC boost converter dedicated to photovoltaic sources based on the modeling of the behavior of the coil or the inductance as a function of the switching frequency.

Multiple low frequency dual reference PWM control of a grid connected photovoltaic three phase NPC inverter with DC/DC boost converter

Directory of Open Access Journals (Sweden)

Mechouma Rabiaa

2014-01-01

Full Text Available In recent years, power demand of industrial applications has increased significantly reaching some megawatts. The use of multilevel converters for applications of medium and high powers is proposed as a solution to drawback semiconductor technology. A multilevel converter not only achieves high power ratings, but also enables the use of renewable energy sources. Renewable energy sources such as photovoltaic can be easily interfaced to a multilevel converter system for a high power application. This paper presents the simulation study in Matlab/Simulink of a grid connected photovoltaic three phase Neutral Point Clamped (NPC inverter with DC/DC boost converter for constant and variable solar radiation.

Grid Converters for Photovoltaic and Wind Power Systems

DEFF Research Database (Denmark)

Teodorescu, Remus; Liserre, Marco; Rodriguez, Pedro

power, operation within a wide range of voltage and frequency, voltage ride-through capability, reactive current injection during faults, grid services support. This book explains the topologies, modulation and control of grid converters for both photovoltaic and wind power applications. In addition...... to power electronics, this book focuses on the specific applications in photovoltaic wind power systems where grid condition is an essential factor. With a review of the most recent grid requirements for photovoltaic and wind power systems, the book discusses these other relevant issues: Modern grid...... inverter topologies for photovoltaic and wind turbines Islanding detection methods for photovoltaic systems Synchronization techniques based on second order generalized integrators (SOGI) Advanced synchronization techniques with robust operation under grid unbalance condition grid filter design and active...

Design and implementation of DSP based solar converter for photovoltaic systems

Energy Technology Data Exchange (ETDEWEB)

Caliskan, Eser [TUBITAK - MRC, Kocaeli (Turkey). Energy Inst.; Ustun, Ozgur [Istanbul Technical Univ., Maslak (Turkey). Electrical Engineering Dept.

2012-07-01

This study discusses the design and implementation of a DSP controlled converter for photovoltaic system that can track the maximum power point, charge and discharge the battery. In the designed system, the boost converter operates the photovoltaic panels at the maximum power point and the bi-directional battery charger charges and discharges the battery bank as demanded. All required switching and control signals for these converters provided by the high performance C2000 series DSP produced by the Texas Instruments. The current, voltage and temperature data are collected by sensors from power stages by using DSP algorithms and the control signals are generated by the embedded software. The load bus is kept at constant voltage by the bi-directional battery charger. The boost converter is controlled by MPPT algorithms and the current sharing or battery charge modes are implemented depending on the radiation value. The designed photovoltaic system performance is verified by simulation and some experiments. (orig.)

High-Voltage DC-DC Converter Topology for PV Energy Utilization - Investigation and Implementation

DEFF Research Database (Denmark)

Sanjeevikumar, Padmanaban; Blaabjerg, Frede; Wheeler, Patrick

2017-01-01

This paper exploited the utilization of photovoltaic (PV) energy system with high-voltage (HV) output DC-DC converter. Classical boost converters are used for both renewable energy integration and HV applications, but limited by reducing output/efficiency in performance. Moreover, as parasitic...... elements suppress the power transfer ratio, converter needs to maximize the PV energy utilization. This investigation study focused to include additional parasitic elements (voltage-lift technique) to a standard DC-DC buck converter and to overcome all the above drawbacks to maximize the PV power...

Battery charging characteristics in small scaled photovoltaic system using resonant DC-DC converter with electric isolation

International Nuclear Information System (INIS)

Isoda, H.; Kimura, G.; Shioya, M.

1990-01-01

The solar energy has been drawing attention of the whole world as a clean and infinite energy, since the globe resource, the globe ecology and so on came into question. The wide applications of the solar energy are being expected in a range from electric power plants to household systems. But the output power induced in the photovoltaic modules is influenced by an intensity of the solar radiation, a temperature of the solar cells and so on, so the various useful forms of the solar energy are being proposed for a purpose of stable power supply. a system described in this paper is a small scaled photovoltaic system with storage batteries. This paper describes the theoretical analyses of the photovoltaic system using a resonant DC-DC converter in order to clarify a desirable circuit condition, besides the experimental results of the battery charging characteristics are presented

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...

Space satellite power system. [conversion of solar energy by photovoltaic solar cell arrays

Science.gov (United States)

Glaser, P. E.

1974-01-01

The concept of a satellite solar power station was studied. It is shown that it offers the potential to meet a significant portion of future energy needs, is pollution free, and is sparing of irreplaceable earth resources. Solar energy is converted by photovoltaic solar cell arrays to dc energy which in turn is converted into microwave energy in a large active phased array. The microwave energy is beamed to earth with little attenuation and is converted back to dc energy on the earth. Economic factors are considered.

Device for converting electromagnetic radiation energy into electrical energy and method of manufacturing such a device

NARCIS (Netherlands)

2007-01-01

Device (10) for converting electromagnetic radiation energy into electrical energy, comprising at least a photovoltaic element (11) with a radiation-sensitive surface, wherein a covering layer (12) of a material comprising a silicon compound, to which a rare earth element has been added, is present

Case Study - Monitoring the Photovoltaic Panels

OpenAIRE

PACURAR Ana Talida; TOADER Dumitru; PACURAR Cristian

2014-01-01

The photovoltaic cell represents one of the most dynamic and attractive way to converts renewable energy sources in electricity production. That means to convert solar energy into electricity. In this paper is presented a analogy between two types of photovoltaic panels installed, with educational role for students. Also the objective of this paper is to estimate the performance of photovoltaic panels and to provide the best solution for industry. These two types of photovoltaic panels wer...

Photovoltaic and photoelectrochemical conversion of solar energy.

Science.gov (United States)

Grätzel, Michael

2007-04-15

The Sun provides approximately 100,000 terawatts to the Earth which is about 10000 times more than the present rate of the world's present energy consumption. Photovoltaic cells are being increasingly used to tap into this huge resource and will play a key role in future sustainable energy systems. So far, solid-state junction devices, usually made of silicon, crystalline or amorphous, and profiting from the experience and material availability resulting from the semiconductor industry, have dominated photovoltaic solar energy converters. These systems have by now attained a mature state serving a rapidly growing market, expected to rise to 300 GW by 2030. However, the cost of photovoltaic electricity production is still too high to be competitive with nuclear or fossil energy. Thin film photovoltaic cells made of CuInSe or CdTe are being increasingly employed along with amorphous silicon. The recently discovered cells based on mesoscopic inorganic or organic semiconductors commonly referred to as 'bulk' junctions due to their three-dimensional structure are very attractive alternatives which offer the prospect of very low cost fabrication. The prototype of this family of devices is the dye-sensitized solar cell (DSC), which accomplishes the optical absorption and the charge separation processes by the association of a sensitizer as light-absorbing material with a wide band gap semiconductor of mesoporous or nanocrystalline morphology. Research is booming also in the area of third generation photovoltaic cells where multi-junction devices and a recent breakthrough concerning multiple carrier generation in quantum dot absorbers offer promising perspectives.

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

of solar energy. Moreover, a novel transformer configuration enables variable turns ratio controlled by the phase between the two current excitations subjected to the primary windings, allowing a wider input/output range. 1 kW experimental prototype has been built to demonstrate a wellmanaged power flow......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...... different single-input single-output (SISO) dc/dc converters would have been used. To reduce the cost and improve the power density of the system, an integrated three-port isolated dc/dc converter is proposed in this paper. It can realize all functions of the energy delivery due to the fluctuation nature...

A Switched-Capacitor Based High Conversion Ratio Converter for Renewable Energy Applications

DEFF Research Database (Denmark)

Li, Kerui; Yin, Zhijian; Yang, Yongheng

2017-01-01

A high step-up switched-capacitor based converter is proposed in this paper. The proposed converter features high conversion ratio, low voltage stress and continuous input current, which makes it very suitable for renewable energy applications like photovoltaic systems. More importantly...... voltage gain, low voltage stress on the switches, continuous input current, and relatively high efficiency....

Investigation on Fuzzy Logic Based Centralized Control in Four-Port SEPIC/ZETA Bidirectional Converter for Photovoltaic Applications

Directory of Open Access Journals (Sweden)

VENMATHI, M.

2016-02-01

Full Text Available In this paper, a new four-port DC-DC converter topology is proposed to interface renewable energy sources and the load along with the energy storage device. The proposed four-port SEPIC/ZETA bidirectional converter (FP-SEPIC/ZETA BDC converter comprises an isolated output port with two unidirectional and one bidirectional input ports. This converter topology is obtained by the fusion of SEPIC/ZETA BDC and full-bridge converter. This converter topology ensures the non-reversal of output voltage hence it is preferred mostly for battery charging applications. In this work, photovoltaic (PV source is considered and the power balance in the system is achieved by means of distributed maximum power point tracking (DMPPT in the PV ports. The centralized controller is implemented using fuzzy logic controller (FLC and the performance is compared with conventional proportional integral (PI controller. The results offer useful information to obtain the desired output under line and load regulations. Experimental results are also provided to validate the simulation results.

Quasi-Z-Source Half-Bridge DC-DC Converter for Photovoltaic Applications

OpenAIRE

Vinnikov, D; Chub, A; Husev, O; Zaķis, J

2015-01-01

This paper presents a novel quasi-Z-source halfbridge galvanically isolated DC-DC converter intended for the photovoltaic applications. The topology could be envisioned as an alternative to the boost half-bridge DC-DC converter but the benefit of its symmetric structure reduces the threat of transformer saturation due to the dc flux. The proposed converter features the continuous input current and could be used either with one or two input voltage sources.

A New Sliding Mode Controller for DC/DC Converters in Photovoltaic Systems

Directory of Open Access Journals (Sweden)

M. Sarvi

2013-01-01

Full Text Available DC/DC converters are widely used in many industrial and electrical systems. As DC/DC converters are nonlinear and time-variant systems, the application of linear control techniques for the control of these converters is not suitable. In this paper, a new sliding mode controller is proposed as the indirect control method and compared to a simple direct control method in order to control a buck converter in photovoltaic applications. The solar arrays are dependent power sources with nonlinear voltage-current characteristics under different environmental conditions (insolation and temperature. From this point of view, the DC/DC converter is particularly suitable for the application of the sliding mode control in photovoltaic application, because of its controllable states. Simulations are performed in Matlab/Simulink software. The simulation results are presented for a step change in reference voltage and input voltage as well as step load variations. The simulations results of proposed method are compared with the conventional PID controller. The results show the good performance of the proposed sliding mode controller. The proposed method can be used for the other DC/DC converter.

High-Efficiency Photovoltaic System Using Partially-Connected DC-DC Converter

Science.gov (United States)

Uno, Masatoshi; Kukita, Akio; Tanaka, Koji

Power conversion electronics for photovoltaic (PV) systems are desired to operate as efficiently as possible to exploit the power generated by PV modules. This paper proposes a novel PV system in which a dc-dc converter is partially connected to series-connected PV modules. The proposed system achieves high power-conversion efficiency by reducing the passing power and input/output voltages of the converter. The theoretical operating principle was experimentally validated. Resultant efficiency performances of the proposed and conventional systems demonstrated that the proposed system was more efficient in terms of power conversion though the identical converter was used for the both systems.

Theoretical assessment of the maximum power point tracking efficiency of photovoltaic facilities with different converter topologies

Energy Technology Data Exchange (ETDEWEB)

Enrique, J.M.; Duran, E.; Andujar, J.M. [Departamento de Ingenieria Electronica, de Sistemas Informaticos y Automatica, Universidad de Huelva (Spain); Sidrach-de-Cardona, M. [Departamento de Fisica Aplicada, II, Universidad de Malaga (Spain)

2007-01-15

The operating point of a photovoltaic generator that is connected to a load is determined by the intersection point of its characteristic curves. In general, this point is not the same as the generator's maximum power point. This difference means losses in the system performance. DC/DC converters together with maximum power point tracking systems (MPPT) are used to avoid these losses. Different algorithms have been proposed for maximum power point tracking. Nevertheless, the choice of the configuration of the right converter has not been studied so widely, although this choice, as demonstrated in this work, has an important influence in the optimum performance of the photovoltaic system. In this article, we conduct a study of the three basic topologies of DC/DC converters with resistive load connected to photovoltaic modules. This article demonstrates that there is a limitation in the system's performance according to the type of converter used. Two fundamental conclusions are derived from this study: (1) the buck-boost DC/DC converter topology is the only one which allows the follow-up of the PV module maximum power point regardless of temperature, irradiance and connected load and (2) the connection of a buck-boost DC/DC converter in a photovoltaic facility to the panel output could be a good practice to improve performance. (author)

Grid-connected Photovoltaic Micro-inverter with New Hybrid Control LLC Resonant Converter

DEFF Research Database (Denmark)

Xingkui, Mao; Qisheng, Huang; Qingbo, Ke

2016-01-01

A high-efficiency photovoltaic (PV) micro-inverter consisting of two power stages i.e. a LLC resonant converter with a new hybrid control scheme and a dc-ac inverter is proposed, studied and designed in this paper. In the first power stage, the new hybrid control combining pulse-frequency modulat......A high-efficiency photovoltaic (PV) micro-inverter consisting of two power stages i.e. a LLC resonant converter with a new hybrid control scheme and a dc-ac inverter is proposed, studied and designed in this paper. In the first power stage, the new hybrid control combining pulse......-frequency modulation (PFM) and phase-shift pulse-width modulation (PS-PWM) is employed on a full-bridge LLC dc-dc converter, in order to achieve high efficiency when PV output voltage varies in a wide range. Moreover, a maximum power point tracking (MPPT) method based on power perturbation is implemented in the dc...

Operation strategy for a lab-scale grid-connected photovoltaic generation system integrated with battery energy storage

International Nuclear Information System (INIS)

Jou, Hurng-Liahng; Chang, Yi-Hao; Wu, Jinn-Chang; Wu, Kuen-Der

2015-01-01

Highlights: • The operation strategy for grid-connected PV generation system integrated with battery energy storage is proposed. • The PV system is composed of an inverter and two DC-DC converter. • The negative impact of grid-connected PV generation systems on the grid can be alleviated by integrating a battery. • The operation of the developed system can be divided into nine modes. - Abstract: The operation strategy for a lab-scale grid-connected photovoltaic generation system integrated with battery energy storage is proposed in this paper. The photovoltaic generation system is composed of a full-bridge inverter, a DC–DC boost converter, an isolated bidirectional DC–DC converter, a solar cell array and a battery set. Since the battery set acts as an energy buffer to adjust the power generation of the solar cell array, the negative impact on power quality caused by the intermittent and unstable output power from a solar cell array is alleviated, so the penetration rate of the grid-connected photovoltaic generation system is increased. A lab-scale prototype is developed to verify the performance of the system. The experimental results show that it achieves the expected performance

Three port converters used as interface in photovoltaic energy systems

Directory of Open Access Journals (Sweden)

Sarab Al-Chlaihawi

2018-04-01

Full Text Available The aim of this paper is to derive and study a full-bridge three-port converter. Based on the standard design of full-bridge converter, we have modeled and derived a three port converter. The three port converter can be used in renewable energy scenarios, such as solar cells or wind turbines connected to the input port. The input can be taken from two-ports simultaneously or from one port at a time. In order to balance the power mismatch between the input port and load port, the batteries are attached to the third port, to ensure there are no discrepancies in the power generated at the input and power demand at the load. In order to ensure isolation and reduced voltage stress on the switches, a high frequency transformer is also used in the design. The overall design contains four switches, and four diodes. MOSFETs are the strongest candidate for the switches owing to their high switching speed, lower losses and high resistance to higher voltage. Moreover, a buck-boost structure is modeled in order to ensure that it can work for a wide variety of different applications by adjusting the duty cycle of the switches properly. To minimize the switching losses in the converter, Zero-Voltage Switching (ZVS is also achievable in the modeled system.

A Distributed Control Strategy Based on DC Bus Signaling for Modular Photovoltaic Generation Systems With Battery Energy Storage

DEFF Research Database (Denmark)

Sun, Kai; Zhang, Li; Xing, Yan

2011-01-01

on improved dc bus signaling is proposed for a modular photovoltaic (PV) generation system with battery energy storage elements. In this paper, the modular PV generation system is composed of three modular dc/dc converters for PV arrays, two grid-connected dc/ac converters, and one dc/dc converter for battery......, grid-connected inversion, and islanding with constant voltage (CV) generation.The power balance of the system under extreme conditions such as the islanding operation with a full-charged battery is taken into account in this control strategy. The dc bus voltage level is employed as an information......Modular generation system, which consists of modular power conditioning converters, is an effective solution to integrate renewable energy sources with conventional utility grid to improve reliability and efficiency, especially for photovoltaic generation. A distributed control strategy based...

Photovoltaic Power Control Using MPPT and Boost Converter

OpenAIRE

Attou, A.; Massoum, A.; Saidi, M.

2015-01-01

—The studies on the photovoltaic system are extensively increasing because of a large, secure, essentially exhaustible and broadly available resource as a future energy supply. However, the output power induced in the photovoltaic modules is influenced by an intensity of solar cell radiation, temperature of the solar cells. Therefore, to maximize the efficiency of the renewable energy system, it is necessary to track the maximum power point of the input source. In this paper, a new maximum po...

Solar energy: photovoltaics

International Nuclear Information System (INIS)

Goetzberger, A.; Voss, B.; Knobloch, J.

1994-01-01

This textbooks covers the following topics: foundations of photovoltaics, solar energy, P-N junctions, physics of solar cells, high-efficiency solar cells, technology of Si solar cells, other solar cells, photovoltaic applications. (orig.)

Investigations of DC power supplies with optoelectronic transducers and RF energy converters

Science.gov (United States)

Guzowski, B.; Gozdur, R.; Bernacki, L.; Lakomski, M.

2016-04-01

Fiber Distribution Cabinets (FDC) monitoring systems are increasingly popular. However it is difficult to realize such system in passive FDC, due to lack of source of power supply. In this paper investigation of four different DC power supplies with optoelectronic transducers is described. Two converters: photovoltaic power converter and PIN photodiode can convert the light transmitted through the optical fiber to electric energy. Solar cell and antenna RF-PCB are also tested. Results presented in this paper clearly demonstrate that it is possible to build monitoring system in passive FDC. During the tests maximum obtained output power was 11 mW. However all converters provided enough power to excite 32-bit microcontroller with ARM-cores and digital thermometer.

Photovoltaic systems in agriculture

International Nuclear Information System (INIS)

Corba, Z.; Katic, V.; Milicevic, D.

2009-01-01

This paper presents the possibility of using one of the renewable energy resources in agriculture. Specifically, the paper shows the possibility of converting solar energy into electricity through photovoltaic panels. The paper includes the analysis of the energy potential of solar radiation in the AP Vojvodina (Serbia). The results of the analysis can be used for the design of photovoltaic energy systems. The amount of solar energy on the territory of the province is compared with the same data from some European countries, in order to obtain a clear picture of the possibilities of utilization of this type of renewable sources. Three examples of possible application of photovoltaic systems are presented. The first relates to the consumer who is away from the electric distribution network - photovoltaic system in island mode. The remaining two examples relate to the application of photovoltaic power sources in manufacturing plants, flowers or vegetables. Applying photovoltaic source of electrical energy to power pumps for irrigation is highlighted

DC-DC Converter Topology Assessment for Large Scale Distributed Photovoltaic Plant Architectures

Energy Technology Data Exchange (ETDEWEB)

Agamy, Mohammed S; Harfman-Todorovic, Maja; Elasser, Ahmed; Sabate, Juan A; Steigerwald, Robert L; Jiang, Yan; Essakiappan, Somasundaram

2011-07-01

Distributed photovoltaic (PV) plant architectures are emerging as a replacement for the classical central inverter based systems. However, power converters of smaller ratings may have a negative impact on system efficiency, reliability and cost. Therefore, it is necessary to design converters with very high efficiency and simpler topologies in order not to offset the benefits gained by using distributed PV systems. In this paper an evaluation of the selection criteria for dc-dc converters for distributed PV systems is performed; this evaluation includes efficiency, simplicity of design, reliability and cost. Based on this evaluation, recommendations can be made as to which class of converters is best fit for this application.

Renewable energy distributed power system with photovoltaic/ thermal and bio gas power generators

International Nuclear Information System (INIS)

Haider, M.U.; Rehman, S.U.

2011-01-01

The energy shortage and environmental pollution is becoming an important problem in these days. Hence it is very much important to use renewable power technologies to get rid of these problems. The important renewable energy sources are Bio-Energy, Wind Energy, Hydrogen Energy, Tide Energy, Terrestrial Heat Energy, Solar Energy, Thermal Energy and so on. Pakistan is rich in all these aspects particularly in Solar and Thermal Energies. In major areas of Pakistan like in South Punjab, Sind and Baluchistan the weather condition are very friendly for these types of Renewable Energies. In these areas Solar Energy can be utilized by solar panels in conjunction with thermal panels. The Photovoltaic cells are used to convert Solar Energy directly to Electrical Energy and thermal panels can be uses to convert solar energy into heat energy and this heat energy will be used to drive some turbine to get Electrical Energy. The Solar Energy can be absorbed more efficiently by any given area of Solar Panel if these two technologies can be combined in such a way that they can work together. The first part of this paper shows that how these technologies can be combined. Furthermore it is known to all that photovoltaic/thermal panels depend entirely on weather conditions. So in order to maintain constant power a biogas generator is used in conjunction with these. (author)

Three-phase electronic power converter for photovoltaic system connected to power line; Conversor eletronico de potencia trifasico para sistema fotovoltaico conectado a rede eletrica

Energy Technology Data Exchange (ETDEWEB)

Villalva, Marcelo Gradella

2010-10-15

This work is a contribution to the study of power converters for photovoltaic distributed generation systems. The main objective is to present the development and results of a three phase power converter for a grid-connected photovoltaic plant. The work presents experimental results and theoretical studies on the modeling and simulation of photovoltaic devices, regulation of the photovoltaic voltage, maximum power point tracking, and the modeling and control of a two-stage grid-connected power converter. (author)

A high performance DC-DC converter with intelligent control for photovoltaic applications

OpenAIRE

M. Niroomand; M. Sherkat; M. Soheili

2013-01-01

In this paper, a SEPIC (Single-Ended Primary Inductance Converter) with high efficiency has been proposed for photovoltaic applications. In the proposed converter, an auxiliary circuit without any additional switches has been used. The switch works under ZCS and ZVS conditions. No auxiliary switch was added to the circuit, thus any additional drive circuit is not needed. The proposed control system based on fuzzy logic method, has shown the smart accurate and faster tracking of the maximum po...

A software application for energy flow simulation of a grid connected photovoltaic system

International Nuclear Information System (INIS)

Hamad, Ayman A.; Alsaad, Mohammad A.

2010-01-01

A computer software application was developed to simulate hourly energy flow of a grid connected photovoltaic system. This software application enables conducting an operational evaluation of a studied photovoltaic system in terms of energy exchange with the electrical grid. The system model consists of a photovoltaic array, a converter and an optional generic energy storage component that supports scheduled charging/discharging. In addition to system design parameters, the software uses hourly solar data and hourly load data to determine the amount of energy exchanged with electrical grid for each hour of the simulated year. The resulting information is useful in assessing the impact of the system on demand for electrical energy of a building that uses it. The software also aggregates these hourly results in daily, monthly and full year sums. The software finds the financial benefit of the system as the difference in grid electrical energy cost between two simultaneously considered cases. One is with load supplied only by the electrical grid, while the other is with the photovoltaic system present and contributing energy. The software supports the energy pricing scheme used in Jordan for domestic consumers, which is based on slices of monthly consumption. By projecting the yearly financial results on the system lifetime, the application weighs the financial benefit resulting from using the system against its cost, thus facilitating an economical evaluation.

Solar Photovoltaic Energy.

Science.gov (United States)

Ehrenreich, Henry; Martin, John H.

1979-01-01

The goals of solar photovoltaic technology in contributing to America's future energy needs are presented in this study conducted by the American Physical Society. Although the time needed for photovoltaics to become popular is several decades away, according to the author, short-range applications are given. (Author/SA)

Photovoltaic Solar Energy

International Nuclear Information System (INIS)

Gonzalez N, J.C.; Leal C, H.

1998-01-01

A short historical review of the technological advances; the current state and the perspectives of the materials for photovoltaic applications is made. Thereinafter, the general aspects of the physical principles and fundamental parameters that govern the operation of the solar cells are described. To way of the example, a methodology for the design and facilities size of a photovoltaic system is applied. Finally, the perspectives of photovoltaic solar energy in relationship to the market and political of development are mentioned

Stand-Alone Photovoltaic System Operation with Energy Management and Fault Tolerant

International Nuclear Information System (INIS)

Jmashidpour, Ehsan; Poure, Philippe; Gholipour, E.; Saadate, Shahrokh

2017-01-01

This paper presents a stand-alone photovoltaic (PV) system with a fault tolerant operation capability. An energy management method is provided to keep the balance between produced and consumed energy instantaneously. As the storage element, an Ultra-Capacitor (UC) pack is used for facing high frequency variation of the load/source, and batteries are in charge of slow load /source variations. A Maximum Power Point Tracking (MPPT) algorithm is applied to control the boost converter of the PV source to achieve the maximum power. In order to improve the micro-grid service continuity and reliability, a fast fault diagnosis method based on the converter current shape for PV source is applied. Finally, the validity of the proposed energy management and the fault diagnosis method is confirmed by the simulation and experimental results. (author)

Long-term energy output estimation for photovoltaic energy systems using synthetic solar irradiation data

International Nuclear Information System (INIS)

Celik, A.N.

2003-01-01

A general methodology is presented to estimate the monthly average daily energy output from photovoltaic energy systems. Energy output is estimated from synthetically generated solar radiation data. The synthetic solar radiation data are generated based on the cumulative frequency distribution of the daily clearness index, given as a function of the monthly clearness index. Two sets of synthetic solar irradiation data are generated: 3- and 4-day months. In the 3-day month, each month is represented by 3 days and in the 4-day month, by 4 days. The 3- and 4-day solar irradiation data are synthetically generated for each month and the corresponding energy outputs are calculated. A total of 8-year long measured hourly solar irradiation data, from five different locations in the world, is used to validate the new model. The monthly energy output values calculated from the synthetic solar irradiation data are compared to those calculated from the measured hour-by-hour data. It is shown that when the measured solar radiation data do not exist for a particular location or reduced data set is advantageous, the energy output from photovoltaic converters could be correctly calculated

Development of an electronic converter with maximum power point tracking for photovoltaic systems applied to rural electrification; Desenvolvimento de conversor eletronico para maxima transferencia de potencia em sistemas fotovoltaicos aplicados a eletrificacao rural

Energy Technology Data Exchange (ETDEWEB)

Machado Neto, Lauro de Vilhena Brandao [Pontificia Universidade Catolica de Minas Gerais (PUC-Minas), Belo Horizonte, MG (Brazil); Cabral, Claudia Valeria Tavora; Oliveira Filho, Delly [Universidade Federal de Vicosa (UFV), MG (Brazil); Diniz, Antonia Sonia Alves Cardoso [Companhia Energetica de Minas Gerais (CEMIG), Belo Horizonte, MG (Brazil); Cortizo, Porfirio Cabaleiro [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil)

2004-07-01

The maximization of the efficiency in the electric energy conversion is essential to the developing of technical and economic viability of photovoltaic solar energy systems. This paper presents the development of an electronic converter with maximum power point tracking for photovoltaic systems applied to rural electrification. The standalone photovoltaic system used is similar to the systems installed by Companhia Energetica de Minas Gerais - CEMIG in the schools of isolated communities, inside the Solar Light Program. Initially were developed test procedures of the equipment used in the system like photovoltaic generators, electronic ballasts, inverters, charge controllers and batteries, covering minimum performance requirements and in compliance with national and international standards, as possible, due to the instrumentation availability. A data acquisition system was assembled to monitoring the photovoltaic system. A simulation of the system was implemented and the aims were to optimize the project and carry out a comparative study with the monitoring results. The converter with maximum power point tracking consists of a direct current converter in the buck configuration and the control algorithm was implemented in a micro controller, being the first results presented here. After finished the prototype, it will be incorporated in the photovoltaic system and will be accomplished a study of the technical and economic viability. The first results of the tests, of the monitoring and of the converter with maximum power point tracking are helping the sustainability of the systems installed by CEMIG, funding the government initiatives in the quality control of equipment and promoting the development of national technology. (author)

Highly efficient hybrid energy generator: coupled organic photovoltaic device and randomly oriented electrospun poly(vinylidene fluoride) nanofiber.

Science.gov (United States)

Park, Boongik; Lee, Kihwan; Park, Jongjin; Kim, Jongmin; Kim, Ohyun

2013-03-01

A hybrid architecture consisting of an inverted organic photovoltaic device and a randomly-oriented electrospun PVDF piezoelectric device was fabricated as a highly-efficient energy generator. It uses the inverted photovoltaic device with coupled electrospun PVDF nanofibers as tandem structure to convert solar and mechanical vibrations energy to electricity simultaneously or individually. The power conversion efficiency of the photovoltaic device was also significantly improved up to 4.72% by optimized processes such as intrinsic ZnO, MoO3 and active layer. A simple electrospinning method with the two electrode technique was adopted to achieve a high voltage of - 300 mV in PVDF piezoelectric fibers. Highly-efficient HEG using voltage adder circuit provides the conceptual possibility of realizing multi-functional energy generator whenever and wherever various energy sources are available.

Energy Efficiency Enhancement of Photovoltaics by Phase Change Materials through Thermal Energy Recovery

Directory of Open Access Journals (Sweden)

Ahmad Hasan

2016-09-01

Full Text Available Photovoltaic (PV panels convert a certain amount of incident solar radiation into electricity, while the rest is converted to heat, leading to a temperature rise in the PV. This elevated temperature deteriorates the power output and induces structural degradation, resulting in reduced PV lifespan. One potential solution entails PV thermal management employing active and passive means. The traditional passive means are found to be largely ineffective, while active means are considered to be energy intensive. A passive thermal management system using phase change materials (PCMs can effectively limit PV temperature rises. The PCM-based approach however is cost inefficient unless the stored thermal energy is recovered effectively. The current article investigates a way to utilize the thermal energy stored in the PCM behind the PV for domestic water heating applications. The system is evaluated in the winter conditions of UAE to deliver heat during water heating demand periods. The proposed system achieved a ~1.3% increase in PV electrical conversion efficiency, along with the recovery of ~41% of the thermal energy compared to the incident solar radiation.

Magnetically integrated high step-up resonant DC-DC converter for distributed photovoltaic systems

DEFF Research Database (Denmark)

Vinnikov, Dmitri; Chub, Andrii; Liivik, Elizaveta

2017-01-01

In this paper magnetically integrated resonant single-switch quasi-Z-source DC-DC converter is evaluated as a candidate topology for the low-cost photovoltaic microconverter. The derivation of the topology and its basic operation principle are explained. Generalized design guidelines...

Photovoltaic AC fusion converter (PVAC). Design consideration and experimental evaluation; Taiyoko hatsuden denryoku/shoyo denryoku kongo sochi no hoshiki to seino

Energy Technology Data Exchange (ETDEWEB)

Tsuchiya, Y. [Hachinohe National College of Technology, Aomori (Japan); Sakakibara, T. [Toyohashi University, of Technology, Aichi (Japan)

1997-11-25

The photovoltaic AC fusion converter (PVAC), of which cost reduction of the total system is possible, was developed. PVAC controls the supply of commercial power by preferentially supplying photovoltaic power to loads for realization of energy conservation. Further, setting the maximum output of solar cell less than the rated load, the system was made the one with no need of storage batteries. This system was realized in a hybrid of the conventional rectification technology and the stand-alone maximum power point tracking photovoltaic system technology. The solar cell input efficiency had been measured as 84% at maximum. Main losses are consumption power of power source, switching loss of inverter, and continuity loss of diode. Ninety-seven percent of the commercial power input efficiency was obtained. Main losses are consumption power of power source, continuity loss of diode bridge, and resistance loss of smoothing reactor. The effect of energy conservation by the use of PVAC was also admitted. 6 refs., 7 figs.

Design and Experiment Analysis of a Direct-Drive Wave Energy Converter with a Linear Generator

OpenAIRE

Jing Zhang; Haitao Yu; Zhenchuan Shi

2018-01-01

Coastal waves are an abundant nonpolluting and renewable energy source. A wave energy converter (WEC) must be designed for efficient and steady operation in highly energetic ocean environments. A direct-drive wave energy conversion (D-DWEC) system with a tubular permanent magnet linear generator (TPMLG) on a wind and solar photovoltaic complementary energy generation platform is proposed to improve the conversion efficiency and reduce the complexity and device volume of WECs. The operating pr...

Analysis and integration of multilevel inverter configuration with boost converters in a photovoltaic system

International Nuclear Information System (INIS)

Prabaharan, N.; Palanisamy, K.

2016-01-01

Highlights: • Integration of MLI with boost converters in photovoltaic system including MPPT. • Results are taken for different irradiations and different temperature condition. • Proposed system is tested with sudden step changes from standard test condition. • Analysis of switching losses and conduction loss is discussed. • Theoretical calculation of % THD using asymptotic formula is discussed. - Abstract: This paper proposes a single phase multilevel inverter configuration that conjoins three series connected full bridge inverter and a single half bridge inverter for renewable energy application especially photo-voltaic system. This configuration of multilevel inverter reduces the value of total harmonic distortion. The half bridge inverter utilized in the proposed configuration increases the output voltage level to nearly twice the output voltage level of a conventional cascaded H-bridge multilevel inverter. This higher output voltage level is generated with lesser number of power semiconductor switches compared to conventional configuration, thus reducing the total harmonic distortion and switching losses. The effectiveness of the proposed configuration is illustrated by replacing the isolated DC sources in multilevel inverter with individual photo-voltaic panels using separate perturb and observer based maximum power point tracking and boost converters. The verification of the proposed system is demonstrated successfully using MATLAB/Simulink based simulation with different irradiation and temperature conditions. Also, the transient operation of the system is verified with results depicted using step change in standard test condition. In the proposed system, total harmonic distortion of the output voltage is 9.85% without using passive filters and 3.91% with filter inductance. Theoretical calculation of the power losses and total harmonic distortion with mathematical equations are discussed. Selective experimental results are presented to prove the

Photovoltaic energy in Germany: experience feedback

International Nuclear Information System (INIS)

Persem, Melanie

2011-01-01

This document presents some key information and figures about the development of photovoltaic energy in Germany: resource potential, 2000-2010 development, share in the energy mix, market, legal framework and incentives, market evolution and electricity feed-in tariffs, 2006-2011 evolution of photovoltaic power plant costs, households' contribution, R and D investments, industry development and employment, the German national energy plan after Fukushima, the expectations of the German photovoltaic industry

Photovoltaic Cells and Systems: Current State and Future Trends

OpenAIRE

Hadj Bourdoucen; Joseph A. Jervase; Abdullah Al-Badi; Adel Gastli; Arif Malik

2000-01-01

Photovoltaics is the process of converting solar energy into electrical energy. Any photovoltaic system invariably consists of solar cell arrays and electric power conditioners. Photovoltaic systems are reliable, quiet, safe and both environmentally benign and self-sustaining. In addition, they are cost-effective for applications in remote areas. This paper presents a review of solar system components and integration, manufacturing, applications, and basic research related to photovoltaics. P...

Delta-Connected Cascaded H-Bridge Multilevel Converters for Large-Scale Photovoltaic Grid Integration

DEFF Research Database (Denmark)

Yu, Yifan; Konstantinou, Georgios; Townsend, Christopher D.

2017-01-01

The cascaded H-bridge (CHB) converter is becoming a promising candidate for use in next generation large-scale photovoltaic (PV) power plants. However, solar power generation in the three converter phase-legs can be significantly unbalanced, especially in a large geographically-dispersed plant....... The power imbalance between the three phases defines a limit for the injection of balanced three-phase currents to the grid. This paper quantifies the performance of, and experimentally confirms, the recently proposed delta-connected CHB converter for PV applications as an alternative configuration...... for large-scale PV power plants. The required voltage and current overrating for the converter is analytically developed and compared against the star-connected counterpart. It is shown that the delta-connected CHB converter extends the balancing capabilities of the star-connected CHB and can accommodate...

ENEA activities on photovoltaic energy

International Nuclear Information System (INIS)

Coiante, D.; Messana, C.

1989-01-01

Photovoltaic conversion appears to be a promising technology for producing electricity. Photovoltaic (PV) solar cells directly convert sun radiation into electricity, without needing moving parts or any kind of fuel. In a long term perspective, PV conversion is expected to become an integrative energy source; at present, high costs are the main limiting factor of the diffusion of PV technology. Costs can be reduced through the joint effect of technological innovation and mass production: therefore, the Italian strategy consists in promoting the gradual enlargement of production volumes and, at the same time, the introduction of less expensive technologies and processes, as soon as they become available. The main responsibility for PV strategies and activities is assigned to ENEA, the Italian National Commission for Nuclear and Alternative Energy Sources. The ENEA five year plan (1985-1989) had allocated about 100 M$ in the PV sector and, as a result, today ENEA is the main national organization promoting PV energy development. ENEA programs include both in house research and external activities. The latter are carried out by universities and industrial firms and concern the whole PV production process from raw materials to complete systems. In Italy there are three main industrial enterprises which produce PV modules an systems: Italsolar (formerly Pragma, ENI group), Ansaldo (IRI group) and Helios Technology, a private firm. Their total annual production capacity amounts to about 2 MW per shift, and is expected to increase in the near future. In 1986, the whole production has been about 0.7 MW: a substantial share of this production has been marketed abroad, mostly as complete systems. (author). 6 tabs

Analytical Comparison of Dual-Input Isolated dc-dc Converter with an ac or dc Inductor for Renewable Energy Systems

DEFF Research Database (Denmark)

Zhang, Zhe; Mira Albert, Maria del Carmen; Andersen, Michael A. E.

2017-01-01

This paper presents two configurations of dualinput (DI) or three-port (TPC) isolated dc-dc converters for hybrid renewable energy systems such as photovoltaics and batteries. These two converters are derived by integrating an interleaved boost converter and a single-active bridge converter...... and control perspective, distinct in operation principles, voltage/power transfer functions, loss distributions, soft-switching constraints, and power efficiency under the same operating conditions. Moreover, the inductor design differs greatly between these two cases. In this paper, a comprehensive...

Hydrogen as the solar energy translator. [in photochemical and photovoltaic processes

Science.gov (United States)

Kelley, J. H.

1979-01-01

Many concepts are being investigated to convert sunlight to workable energy forms with emphasis on electricity and thermal energy. The electrical alternatives include direct conversion of photons to electricity via photovoltaic solar cells and solar/thermal production of electricity via heat-energy cycles. Solar cells, when commercialized, are expected to have efficiencies of about 12 to 14 percent. The cells would be active about eight hours per day. However, solar-operated water-splitting process research, initiated through JPL, shows promise for direct production of hydrogen from sunlight with efficiencies of up to 35 to 40 percent. The hydrogen, a valuable commodity in itself, can also serve as a storable energy form, easily and efficiently converted to electricity by fuel cells and other advanced-technology devices on a 24-hour basis or on demand with an overall efficiency of 25 to 30 percent. Thus, hydrogen serves as the fundamental translator of energy from its solar form to electrical form more effectively, and possibly more efficiently, than direct conversion. Hydrogen also can produce other chemical energy forms using solar energy.

Conference: photovoltaic energy - local authorities - Citizen

International Nuclear Information System (INIS)

Belon, Daniel; Witte, Sonja; Simonet, Luc; Waldmann, Lars; Fouquet, Doerte; Dupassieux, Henri; Longo, Fabio; Brunel, Arnaud; Kruppert, Andreas; Vachette, Philippe

2012-01-01

The French-German office for Renewable energies (OFAEnR) organised a conference on the role of photovoltaic energy, local authorities and Citizens as pillars of the energy transition. In the framework of this French-German exchange of experience, about 100 participants exchanged views on the role of local authorities and Citizens in the implementation of the energy transition. This document brings together the available presentations (slides) made during this event: 1 - Solar photovoltaics, local communities and citizens - Cornerstones of the energy revolution. Franco-German viewpoints (Daniel Belon); 2 - Structure and management of the distribution system operators in Germany. efficient, innovative and reliable: Local public enterprises in Germany (Sonja Witte); 3 - Photovoltaic energy: technical challenges for power grids - A distribution network operator's (DNO) point-of-view (Luc Simonet); 4 - The sun and the grid - challenges of the energy transition (Lars Waldmann); 5 - The role of local public authorities in the networks management: legal situation in France, Germany and in the EU (Doerte Fouquet); 6 - Towards energy transition: challenges for renewable energies - Urban solar planning tools (Henri Dupassieux); 7 - The local energy supply as a municipal task - solar land-use planning in practice in Germany (Fabio Longo); 8 - Supporting and facilitating the financing of photovoltaic projects at a community level (Arnaud Brunel); 9 - Photovoltaics in the municipality VG Arzfeld (Andreas Kruppert); 10 - For the energy revolution to be a success: Invest into renewable energy. Local, controllable and renewable 'shared energy' that is grassroots (Philippe Vachette)

Maximum power point tracking for photovoltaic applications by using two-level DC/DC boost converter

Science.gov (United States)

Moamaei, Parvin

Recently, photovoltaic (PV) generation is becoming increasingly popular in industrial applications. As a renewable and alternative source of energy they feature superior characteristics such as being clean and silent along with less maintenance problems compared to other sources of the energy. In PV generation, employing a Maximum Power Point Tracking (MPPT) method is essential to obtain the maximum available solar energy. Among several proposed MPPT techniques, the Perturbation and Observation (P&O;) and Model Predictive Control (MPC) methods are adopted in this work. The components of the MPPT control system which are P&O; and MPC algorithms, PV module and high gain DC-DC boost converter are simulated in MATLAB Simulink. They are evaluated theoretically under rapidly and slowly changing of solar irradiation and temperature and their performance is shown by the simulation results, finally a comprehensive comparison is presented.

Design and Experimentation of a Control System Implemented on Raspberry Pi 3 Board for Photovoltaic Systems Using SEPIC Converter

Directory of Open Access Journals (Sweden)

Mohamed Boutouba

2017-12-01

Full Text Available In this paper, a voltage regulation system is proposed for photovoltaic energy sources (PV, using Single-Ended Primary Inductance Converter as a DC-DC converter to feed loads working with specific input voltage. The choose of SEPIC converter is due to the output voltage ripple of developed-type converters are usually small and can be lower than 2%, also it considered as a buck and boost converter and thereafter loads with lower or higher voltage could be powered. Matlab Simulink is used as environment to develop control strategies to guaranties a stable voltage at the loads terminals. Two algorithms are used to fulfill this role: A Conventional PID and PI-Fuzzy logic controller to generate the PWM signal for the SEPIC converter. Hence, to validate the work some real-time simulations are treated by implemented the control strategies on a low-cost control board: The Raspberry Pi 3 in order to manage the operation of system and collecting the simulation data. Also, and for verification purposes, several simulations were treated to verify the good behavior of the proposed system.

A new DC/AC boost transformerless converter in application of photovoltaic power generation

DEFF Research Database (Denmark)

Wei, Mo; Loh, Poh Chiang; Blaabjerg, Frede

2011-01-01

This paper presents a new DC/AC boost transformerless converter in the applications of photovoltaic (PV) power generation. A new circuit topology of single phase full bridge power inverter with additional DC/DC boost stage is proposed. The proposed topology overcomes two commonly existing......, and then converts the DC into AC to supply the load. A special modulation technique is proposed to eliminate the leakage current which is commonly presents in PV transformerless power generation, helps to increase the system efficiency and output performance....

Exergy analysis of photovoltaic solar collector

International Nuclear Information System (INIS)

Sopian, K.; Othman, M.Y.Hj.

1998-01-01

The exergy analysis (availability or second law analysis) is applied to the photovoltaic thermal solar collector. Photovoltaic thermal collector is a special type of solar collector where electricity and heat are produced simultaneously. The electricity produced from the photovoltaic thermal collector is all converted into useful work. The available quantity of the heat collected can readily be determined by taking into account both the quantity (heat quantity) and quality ( a function of temperature) of the thermal energy. Therefore, using the concept of exergy allows heat produced from the thermal collector and the electricity generated from the photovoltaic cells to be compared or to be evaluated on the basis of a common measure such as the effectiveness on solar energy collection or the total amount of available energy. In this paper, the effectiveness of solar energy collection is called combined photovoltaic thermal exergy efficiency. An experimental setup of a double pas photovoltaic thermal solar collector has been deigned, fabricated and tested. (author)

Photovoltaic power converter system with a controller configured to actively compensate load harmonics

Science.gov (United States)

de Rooij, Michael Andrew; Steigerwald, Robert Louis; Delgado, Eladio Clemente

2008-12-16

Photovoltaic power converter system including a controller configured to reduce load harmonics is provided. The system comprises a photovoltaic array and an inverter electrically coupled to the array to generate an output current for energizing a load connected to the inverter and to a mains grid supply voltage. The system further comprises a controller including a first circuit coupled to receive a load current to measure a harmonic current in the load current. The controller includes a second circuit to generate a fundamental reference drawn by the load. The controller further includes a third circuit for combining the measured harmonic current and the fundamental reference to generate a command output signal for generating the output current for energizing the load connected to the inverter. The photovoltaic system may be configured to compensate harmonic currents that may be drawn by the load.

Electricity from Sunlight: The Future of Photovoltaics. Worldwatch Paper 52.

Science.gov (United States)

Flavin, Christopher

Solar photovoltaic cells have been called the ultimate energy technology, environmentally benign and without moving parts, solar cells directly convert sunlight into electricity. Photovoltaic energy conversion is fundamentally different from all other forms of electricity generation. Without turbines, generators or other mechanical equipment, it…

Photovoltaic solar energy; Photovoltaische Solarenergie

Energy Technology Data Exchange (ETDEWEB)

NONE

2012-07-01

Within the 27th symposium of the Ostbayerische Technologie-Transfer-Institut e.V. (Regensburg, Federal Republic of Germany) from 29th February to 02th March, 2012, at Banz monastery near Bad Staffelstein (Federal Republic of Germany), the following lectures were held: (1) EEG 12: State of the art and impacts (K. Freier); (2) Promising markets - PV market potentials Europe (M. Lohr); (3) Expansion requires restructuring - Research promotion for renewable energy and renewable energy supply systems (K. Deller); (4) Fields of application and potentials of photovoltaics in Germany without an enhanced EEG compensation (V. Quaschning); (5) ''Smart Solar Grid'' - Results of the analysis and solar roof potential of the first test area of the public utility Ulm (H. Ruf); (6) Power limitation at PV plants - Adjustment of modelling methods and comparison of different location (J. von Appen); (7) Exploitations to the power limitation till to 70 % of the module capacity (B. Giesler); (8) Actual procedural results of the clearing house EEG to photovoltaics and modifications at PV by means of the EEG 2012 (M. Winkler); (9) Grid integration of PV plants from a legal point of view (M. von Oppen); (10) EEG 2012 - Abetment or brake? PV and other renewable energies in comparison (M. Reichmuth); (11) On the precision of radiation and photovoltaics component models (J. Schumacher); (12) Impact of global radiation data with different properties on the performance ratio and prognosticated energy efficiency of photovoltaic power plants (M. Egler); (13) Quantification of superelevations of irradiation in high-resolution DWD datasets for different locations in Germany (M. Zehner); (14) Prognosis of the regional PV performance with measuring data of PV plant and satellite pictures (Y.-M. Saint-Drenan); (15) Photovoltaics and wind power: perfectly complementing power technologies using Central Germany as an example (C. Breyer); (16) Which and how much storages are necessary

A Multifunctional Isolated and Non-Isolated Dual Mode Converter for Renewable Energy Conversion Applications

Directory of Open Access Journals (Sweden)

Yiwang Wang

2017-11-01

Full Text Available In this paper, a multifunctional isolated and non-isolated dual-mode low-power converter was designed for renewable energy conversion applications such as photovoltaic power generation to achieve different operating modes under bi-directional electrical conversion. The proposed topology consists of a bidirectional non-isolated DC/DC circuit and an isolated converter with a high-frequency transformer, which merge the advantages of both the conventional isolated converter and non-isolated converter with the combination of the two converter technologies. Compared with traditional converters, the multifunctional converter can not only realize conventional bi-directional functions, but can also be applied for many different operation modes and meet the high output/input ratio demands with the two converter circuits operating together. A novel control algorithm was proposed to achieve the various functions of the proposed converter. An experimental platform based on the proposed circuit was established. Both the simulation and experimental results indicated that the proposed converter could provide isolated and non-isolated modes in different applications, which could meet different practical engineering requirements.

Asymmetrical Interleaved DC/DC Switching Converters for Photovoltaic and Fuel Cell Applications—Part 1: Circuit Generation, Analysis and Design 

Directory of Open Access Journals (Sweden)

Sergio Serna

2012-11-01

Full Text Available A novel asymmetrical interleaved dc/dc switching converters family intended for photovoltaic and fuel cell applications is presented in this paper. The main requirements on such applications are small ripples in the generator and load, as well as high voltage conversion ratio. Therefore, interleaved structures and voltage multiplier cells have been asymmetrically combined to generate new converters, which inherently operate indiscontinuous conduction mode. The novel family is derived from boost, buck-boost and flyback-based structures. This converter family is analyzed to obtain the design equations and synthesize a design process based on the typical requirements of photovoltaic and fuel cell applications. Finally, the experimental results validate the characteristics and usefulness of the asymmetrical interleaved converter family. 

Photovoltaic energy systems. Program summary

Energy Technology Data Exchange (ETDEWEB)

None

1982-01-01

The ongoing research, development, and demonstration efforts of the Photovoltaics Program are highlighted and each of the US Department of Energy's current photovoltaics projects initiated or renewed during fiscal year 1981 is described, including its title, directing organization, project engineer, contractor, principal investigator, contract period, funding, and objectives. The Photovoltaics Program is briefly summarized, including the history and organization and highlights of the research and development and of planning, assessment, and integration. Also summarized is the Federal Photovoltaic Utilization Program. An exhaustive bibliography is included. (LEW)

The photovoltaic energy in Japan

International Nuclear Information System (INIS)

Georgel, O.

2005-07-01

Today the Japan is the leader of the photovoltaic energy. The first reason of this success is an action of the government integrating subventions for the installation of photovoltaic systems and a support of the scientific research. To explain this success, the author presents the energy situation in Japan, details the national programs, the industrial sector (market, silicon needs, recycling, manufacturers, building industry) and presents the main actors. (A.L.B.)

Performance Comparison between ĆUK and SEPIC Converters for Maximum Power Point Tracking Using Incremental Conductance Technique in Solar Power Applications

OpenAIRE

James Dunia; Bakari M. M. Mwinyiwiwa

2013-01-01

Photovoltaic (PV) energy is one of the most important energy resources since it is clean, pollution free, and endless. Maximum Power Point Tracking (MPPT) is used in photovoltaic (PV) systems to maximize the photovoltaic output power, irrespective the variations of temperature and radiation conditions. This paper presents a comparison between Ćuk and SEPIC converter in maximum power point tracking (MPPT) of photovoltaic (PV) system. In the paper, advantages and disadvantages of both converter...

Three-phase Photovoltaic Systems

DEFF Research Database (Denmark)

Kerekes, Tamas; Sera, Dezso; Máthé, Lászlo

2015-01-01

, detailing the different photovoltaic inverter structures and topologies as well as discussing the different control layers within a grid-connected photovoltaic plant. Modulation schemes for various photovoltaic inverter topologies, grid synchronization, current control, active and reactive power control......Photovoltaic technology has experienced unprecedented growth in the last two decades, transforming from mainly off-grid niche generation to a major renewable energy technology, reaching approximately 180 GW of capacity worldwide at the end of 2014. Large photovoltaic power plants interfacing...... the grid through a three-phase power electronic converter are now well on the way to becoming a major player in the power system in many countries. Therefore, this article gives an overview of photovoltaic systems with a focus on three-phase applications, presenting these both from a hardware point of view...

Photovoltaic technology diffusion. Contact and interact

International Nuclear Information System (INIS)

Kruijsen, J.

1999-09-01

How can the diffusion of photovoltaic technologies be advanced? Photovoltaics convert light into electrical energy. They are environmentally friendly, reliable and have minimal maintenance requirements. Up to now, their introduction into the electricity market has been dominated by a technology push perspective. However, this has not yet resulted in a large-scale implementation. This thesis describes a network approach to advance photovoltaic diffusion and presents four guiding principles intended for the parties concerned: those who supply the photovoltaic technologies (e.g., developers of photovoltaic cells); those who integrate photovoltaic technologies into (new) product systems (e.g., engineering firms); the users of photovoltaic systems (e.g., housing corporations); and those who stimulate the use of photovoltaics (e.g., policymakers, subsidisers, branch organisations, financial institutes, and NGOs). refs

Enlarging photovoltaic effect: combination of classic photoelectric and ferroelectric photovoltaic effects.

Science.gov (United States)

Zhang, Jingjiao; Su, Xiaodong; Shen, Mingrong; Dai, Zhihua; Zhang, Lingjun; He, Xiyun; Cheng, Wenxiu; Cao, Mengyu; Zou, Guifu

2013-01-01

Converting light energy to electrical energy in photovoltaic devices relies on the photogenerated electrons and holes separated by the built-in potential in semiconductors. Photo-excited electrons in metal electrodes are usually not considered in this process. Here, we report an enhanced photovoltaic effect in the ferroelectric lanthanum-modified lead zirconate titanate (PLZT) by using low work function metals as the electrodes. We believe that electrons in the metal with low work function could be photo-emitted into PLZT and form the dominant photocurrent in our devices. Under AM1.5 (100 mW/cm²) illumination, the short-circuit current and open-circuit voltage of Mg/PLZT/ITO are about 150 and 2 times of those of Pt/PLZT/ITO, respectively. The photovoltaic response of PLZT capacitor was expanded from ultraviolet to visible spectra, and it may have important impact on design and fabrication of high performance photovoltaic devices based on ferroelectric materials.

Solar energy photovoltaic technology: proficiency and performance

International Nuclear Information System (INIS)

2006-01-01

Total is committed to making the best possible of the planet's fossil fuel reserves while fostering the emergence of other solutions, notably by developing effective alternatives. Total involves in photovoltaics when it founded in 1983 Total Energies, renamed Tenesol in 2005, a world leader in the design and installation of photovoltaic solar power systems. This document presents Total's activities in the domain: the global challenge of energy sources and the environment, the energy collecting by photovoltaic electricity, the silicon technology for cell production, solar panels and systems to distribute energy, research and development to secure the future. (A.L.B.)

Information report from the Economic Affairs commission on photovoltaic energy

International Nuclear Information System (INIS)

2009-01-01

Today and for several years to come, photovoltaic energy represents only a minimal part of the world's electric power production. Photovoltaic energy is only at its beginnings, however several countries have already taken opportunities in the business. This report gives a comprehensive information about photovoltaic energy (basic principles, conversion systems, photovoltaic power plants, incentive programs in other developed countries, regulations ...) and arguments for the development of a structured photovoltaic energy policy in France

An Original Transformer and Switched-Capacitor (T & SC-Based Extension for DC-DC Boost Converter for High-Voltage/Low-Current Renewable Energy Applications: Hardware Implementation of a New T & SC Boost Converter

Directory of Open Access Journals (Sweden)

Sanjeevikumar Padmanaban

2018-03-01

Full Text Available In this article a new Transformer and Switched Capacitor-based Boost Converter (T & SC-BC is proposed for high-voltage/low-current renewable energy applications. The proposed T & SC-BC is an original extension for DC-DC boost converter which is designed by utilizing a transformer and switched capacitor (T & SC. Photovoltaic (PV energy is a fast emergent segment among the renewable energy systems. The proposed T & SC-BC combines the features of the conventional boost converter and T & SC to achieve a high voltage conversion ratio. A Maximum Power Point Tracking (MPPT controller is compulsory and necessary in a PV system to extract maximum power. Thus, a photovoltaic MPPT control mechanism also articulated for the proposed T & SC-BC. The voltage conversion ratio (Vo/Vin of proposed converter is (1 + k/(1 − D where, k is the turns ratio of the transformer and D is the duty cycle (thus, the converter provides 9.26, 13.88, 50/3 voltage conversion ratios at 78.4 duty cycle with k = 1, 2, 2.6, respectively. The conspicuous features of proposed T & SC-BC are: (i a high voltage conversion ratio (Vo/Vin; (ii continuous input current (Iin; (iii single switch topology; (iv single input source; (v low drain to source voltage (VDS rating of control switch; (vi a single inductor and a single untapped transformer are used. Moreover, the proposed T & SC-BC topology was compared with recently addressed DC-DC converters in terms of number of components, cost, voltage conversion ratio, ripples, efficiency and power range. Simulation and experimental results are provided which validate the functionality, design and concept of the proposed approach.

Energy management in buildings using photovoltaics

CERN Document Server

Papadopoulou, Elena

2012-01-01

Although fossil fuels remain the primary global energy source, developing and expanding economies are creating an ever-widening gap between supply and demand. Efficient energy management offers a cost-effective opportunity for both industrialized and developing nations to limit the enormous financial and environmental costs associated with burning fossil fuels. The implication of photovoltaic systems in particular presents the potential for clean and sustainable electrical energy to be generated from an unrestricted source. Energy Management in Buildings Using Photovoltaics demonstrates how ad

Photovoltaic energy generation in Germany

International Nuclear Information System (INIS)

Anon.

1993-01-01

An overview is given of the current state of the art regarding photovoltaic research and demonstration programmes in the Federal Republic of Germany. Also attention is paid to the companies and research institutes involved, and the long-term economical and technical prospects of photovoltaic energy. 13 figs., 4 tabs., 10 refs

Press document. Photovoltaic energy: boosting the evolution

International Nuclear Information System (INIS)

2009-04-01

The french potential in the photovoltaic energy is considerable but not very exploited. In this context the CEA, by its function of applied research institute in the domain of the low carbon energies can be a major actor of the sector development. This document presents the research programs in the photovoltaic domain, developed at the CEA, especially on the silicon performance, the photovoltaic solar cells and their integration in the buildings. (A.L.B.)

Highway renewable energy : photovoltaic noise barriers

Science.gov (United States)

2017-07-01

Highway photovoltaic noise barriers (PVNBs) represent the combination of noise barrier systems and photovoltaic systems in order to mitigate traffic noise while simultaneously producing renewable energy. First deployed in Switzerland in 1989, PVNBs a...

Technologic Information about Photovoltaic Applied in Urban Residences

OpenAIRE

Stephanie Fabris Russo; Daiane Costa Guimarães; Jonas Pedro Fabris; Maria Emilia Camargo; Suzana Leitão Russo; José Augusto Andrade Filho

2016-01-01

Among renewable energy sources, solar energy is the one that has stood out. Solar radiation can be used as a thermal energy source and can also be converted into electricity by means of effects on certain materials, such as thermoelectric and photovoltaic panels. These panels are often used to generate energy in homes, buildings, arenas, etc., and have low pollution emissions. Thus, a technological prospecting was performed to find patents related to the use of photovoltaic plates in urban re...

Performance of Series Connected GaAs Photovoltaic Converters under Multimode Optical Fiber Illumination

Directory of Open Access Journals (Sweden)

Tiqiang Shan

2014-01-01

Full Text Available In many military and industrial applications, GaAs photovoltaic (PV converters are connected in series in order to generate the required voltage compatible with most common electronics. Multimode optical fibers are usually used to carry high-intensity laser and illuminate the series connected GaAs PV converters in real time. However, multimode optical fiber illumination has a speckled intensity pattern. The series connected PV array is extremely sensitive to nonuniform illumination; its performance is limited severely by the converter that is illuminated the least. This paper quantifies the effects of multimode optical fiber illumination on the performance of series connected GaAs PV converters, analyzes the loss mechanisms due to speckles, and discusses the maximum illumination efficiency. In order to describe the illumination dependent behavior detailedly, modeling of the series connected PV array is accomplished based on the equivalent circuit for PV cells. Finally, a series of experiments are carried out to demonstrate the theory analysis.

Two novel techniques for increasing energy efficiency of photovoltaic-battery systems

International Nuclear Information System (INIS)

Fathabadi, Hassan

2015-01-01

Highlights: • Two novel techniques for increasing the energy efficiency of PV-battery systems. • Practically, 27% increase in the energy efficiency of PV-battery systems. • Novel proposed DC/PWM inverter for substituting conventional primary DC/DC converters. • Presenting theoretical, simulation & experimental results to verify the above claims. - Abstract: A photovoltaic (PV)-battery power source consists of a PV panel, a primary DC/DC converter, and a battery or a batteries bank. It is generally used to provide electric energy for local consumers such as buildings. Maximum power point tracking (MPPT) schemes cannot be applied to it because the PV panel output current is only determined by the state of charge (SOC) of the battery. In this study, two novel techniques are proposed to increase the energy efficiency of PV-battery power sources. Replacing the primary DC/DC converter with a novel proposed DC/PWM inverter, and decomposing the PV panel into a set of parallel homogenous configured PV modules are the two proposed techniques. It is shown that the implementation of each technique effectively increases the energy efficiency of PV-battery power sources. The two techniques are combined to each other to implement a new PV-battery power source. It is proved that the energy efficiency of the new version is significantly more than conventional version. Simulated results performed in MATLAB/Proteus 6 verify an increase of 29% in the energy efficiency. Four PV-battery power sources have been built, and comparative experimental results are presented that verify an increase of 27% in the energy efficiency.

Optimum energy levels and offsets for organic donor/acceptor binary photovoltaic materials and solar cells

International Nuclear Information System (INIS)

Sun, S.-S.

2005-01-01

Optimum frontier orbital energy levels and offsets of an organic donor/acceptor binary type photovoltaic material have been analyzed using classic Marcus electron transfer theory in order to achieve the most efficient photo induced charge separation. This study reveals that, an exciton quenching parameter (EQP) yields one optimum donor/acceptor frontier orbital energy offset that equals the sum of the exciton binding energy and the charge separation reorganization energy, where the photo generated excitons are converted into charges most efficiently. A recombination quenching parameter (RQP) yields a second optimum donor/acceptor energy offset where the ratio of charge separation rate constant over charge recombination rate constant becomes largest. It is desirable that the maximum RQP is coincidence or close to the maximum EQP. A third energy offset is also identified where charge recombination becomes most severe. It is desirable that the most severe charge recombination offset is far away from maximum EQP offset. These findings are very critical for evaluating and fine tuning frontier orbital energy levels of a donor/acceptor pair in order to realize high efficiency organic photovoltaic materials

Investigation of a demonstrating photo-voltaic system

International Nuclear Information System (INIS)

Platikanov, S.; Markova, D.; Tsankov, P.; Grachki, I.

2002-01-01

A photovoltaic system for converting solar energy into electric energy has been built in the Technical University of Gabrovo. The measurements results of the solar radiation daily variation, temperature, illuminations and other technical characteristics of PV system are shown graphically. (authors)

The photovoltaic energy in Japan; Energie photovoltaique au Japon

Energy Technology Data Exchange (ETDEWEB)

Georgel, O

2005-07-15

Today the Japan is the leader of the photovoltaic energy. The first reason of this success is an action of the government integrating subventions for the installation of photovoltaic systems and a support of the scientific research. To explain this success, the author presents the energy situation in Japan, details the national programs, the industrial sector (market, silicon needs, recycling, manufacturers, building industry) and presents the main actors. (A.L.B.)

Photovoltaic Solar Energy Generation

CERN Document Server

Lotsch, H.K.V; U.Hoffmann, Volker; Rhodes, William T; Asakura, Toshimitsu; Brenner, Karl-Heinz; Hänsch, Theodor W; Kamiya, Takeshi; Krausz, Ferenc; Monemar, Bo; Venghaus, Herbert; Weber, Horst; Weinfurter, Harald

2005-01-01

This comprehensive description and discussion of photovoltaics (PV) is presented at a level that makes it accessible to the interested academic. Starting with an historical overview, the text outlines the relevance of photovoltaics today and in the future. Then follows an introduction to the physical background of solar cells and the most important materials and technologies, with particular emphasis placed on future developments and prospects. The book goes beyond technology by also describing the path from the cell to the module to the system, proceeding to important applications, such as grid-connected and stand-alone systems. The composition and development of the markets and the role of PV in future energy systems are also considered. Finally, the discussion turns to the future structure of energy supplies, expected to comprise more distributed generation, and addresses synergies and competition from other carbon-free energy sources.

Design and performance study of a DC-DC flyback converter based on wide bandgap power devices for photovoltaic applications

Science.gov (United States)

Alharbi, Salah S.; Alharbi, Saleh S.; Al-bayati, Ali M. S.; Matin, Mohammad

2017-08-01

This paper presents a high-performance dc-dc flyback converter design based on wide bandgap (WBG) semiconductor devices for photovoltaic (PV) applications. Two different power devices, a gallium nitride (GaN)-transistor and a silicon (Si)-MOSFET, are implemented individually in the flyback converter to examine their impact on converter performance. The total power loss of the converter with different power devices is analyzed for various switching frequencies. Converter efficiency is evaluated at different switching frequencies, input voltages, and output power levels. The results reveal that the converter with the GaN-transistor has lower total power loss and better efficiency compared to the converter with the conventional Si-MOSFET.

Solar photovoltaic power generation system and understanding of green energy

International Nuclear Information System (INIS)

Yoo, Chun Sik

2004-03-01

This book introduces sunlight generation system and green energy, which includes new and renewable energy such as photovoltaic power generation, solar thermal, wind power, bio energy, waste energy, geothermal energy, ocean energy and fuel cell photovoltaic industry like summary, technology trend, market trend, development strategy of the industry in Korea, and other countries, design of photovoltaic power generation system supporting policy and related business of new and renewable energy.

SSG Wave Energy Converter

DEFF Research Database (Denmark)

Margheritini, Lucia; Vicinanza, Diego; Frigaard, Peter

2008-01-01

The SSG (Sea Slot-cone Generator) is a wave energy converter of the overtopping type. The structure consists of a number of reservoirs one on the top of each others above the mean water level, in which the water of incoming waves is stored temporary. In each reservoir, expressively designed low...... head hydroturbines are converting the potential energy of the stored water into power. A key to success for the SSG will be the low cost of the structure and its robustness. The construction of the pilot plant is scheduled and this paper aims to describe the concept of the SSG wave energy converter...

Conference on photovoltaic energy network parity

International Nuclear Information System (INIS)

Abadie, Pierre-Marie; Masson, Gaetan; Henzelmann, Orsten; Joly, Jean-Pierre; Guillemoles, Jean-Francois; Auffret, Jean-Marc; Berger, Arnaud; Binder, Jann; Martin, David; Beck, Bernhard; Mahuet, Audrey; Mueller, Thorsten; Contamin, Raphael

2012-01-01

The French-German office for Renewable energies (OFAEnR) organised a conference on the present day and future challenges of the development, support and market integration of photovoltaic energy. In the framework of this French-German exchange of experience, about 120 participants exchanged views on support models to renewable energy sources, research results on self-consumption and business models for the renewable energies sector. This document brings together the available presentations (slides) made during this event: 1 - Overview of France's PV support policies (Pierre-Marie Abadie); 2 - Grid parity: first step towards PV competitiveness (Gaetan Masson); 3 - How competitive is solar power? Requirements and impact on the European industry (Orsten Henzelmann); 4 - Key elements of the National Institute of Solar energy - INeS (Jean-Pierre Joly); 5 - Research priorities according to the Paris Institute of Photovoltaics (Jean-Francois Guillemoles); 6 - Bosch Solar energy (Jean-Marc Auffret); 7 - Financing and insuring photovoltaics - History and future prospects (Arnaud Berger); 8 - Decentralized Photovoltaics: Autonomy, Self-Consumption and Reduction of Grid Loading through electrical and Thermal Storage (Jann Binder); 9 - Off Grid systems, mini grid and grid parity, field feedback and perspectives. From the producer-consumer to the smart grid: experience feedback of PV management models (David Martin); 10 - Benefits for solar power plants in respect of grid stabilization (Bernhard Beck); 11 - Renewable energies integration to electricity market: impacts and challenges (Audrey Mahuet); 12 - Promotion of PV in Germany: Feed-in tariffs, self-consumption and direct selling - Review and forecast (Thorsten Mueller); 13 - How to support renewable electricity in France? (Raphael Contamin)

Photovoltaic solar energy conversion

CERN Document Server

Bauer, Gottfried H

2015-01-01

This concise primer on photovoltaic solar energy conversion invites readers to reflect on the conversion of solar light into energy at the most fundamental level and encourages newcomers to the field to help find meaningful answers on how photovoltaic solar energy conversion can work (better), eventually contributing to its ongoing advancement. The book is based on lectures given to graduate students in the Physics Department at the University of Oldenburg over the last two decades, yet also provides an easy-to-follow introduction for doctoral and postdoctoral students from related disciplines such as the materials sciences and electrical engineering. Inspired by classic textbooks in the field, it reflects the author’s own ideas on how to understand, visualize and eventually teach the microscopic physical mechanisms and effects, while keeping the text as concise as possible so as to introduce interested readers to the field and balancing essential knowledge with open questions.

Logistical Impact Study of Photovoltaic Power Converter Technology to the United States Army and the United States Marine Corps

National Research Council Canada - National Science Library

Whiteker, James

2004-01-01

The purpose of this MBA Project was to analyze the logistical and fiscal impact of replacing selected disposable batteries with rechargeable batteries and photovoltaic power converter chargers within...

Development and implementation of a compound converter in solar energy systems

Directory of Open Access Journals (Sweden)

S. J. B. Hartman

1992-07-01

Full Text Available The converter proposed here is a compound photovoltaic converter system that has been implemented with a power rating of 1,5 kVA at an array voltage of 96 V, using a 24 V battery bank. The converter system combines the functions of inversion, battery regulation and maximum power point tracking of the solar array into a single cost-effective converter. Maximum power point tracking is performed by controlling the voltage and frequency of the AC output. A description of this converter, and an explanation of the control strategy employed, are provided together with practical results measured on the prototype converter. This compound topology has a high conversion efficiency from solar array to load.

X-Y Converter Family

DEFF Research Database (Denmark)

Bhaskar, Mahajan Sagar; Sanjeevikumar, Padmanaban; Wheeler, Patrick

2016-01-01

A New breed of a buck boost converter, named as the XY converter family is proposed in this article. In the XY family, 16 topologies are presented which are highly suitable for renewable energy applications which require a high ratio of DC-DC converter; such as a photovoltaic multilevel inverter...... system, high voltage automotive applications and industrial drives. Compared to the traditional boost converter and existing recent converters, the proposed XY converter family has the ability to provide a higher output voltage by using less number of power devices and reactive components. Other distinct...... features of the XY converter family are i) Single control switch ii) Provide negative output voltage iii) Non-isolated topologies iv) High conversion ratio without making the use of high duty cycle and v) modular structure. XY family is compared with the recent high step-up converters and the detailed...

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.

Intelligent Photovoltaic Maximum Power Point Tracking Controller for Energy Enhancement in Renewable Energy System

Directory of Open Access Journals (Sweden)

Subiyanto

2013-01-01

Full Text Available Photovoltaic (PV system is one of the promising renewable energy technologies. Although the energy conversion efficiency of the system is still low, but it has the advantage that the operating cost is free, very low maintenance and pollution-free. Maximum power point tracking (MPPT is a significant part of PV systems. This paper presents a novel intelligent MPPT controller for PV systems. For the MPPT algorithm, an optimized fuzzy logic controller (FLC using the Hopfield neural network is proposed. It utilizes an automatically tuned FLC membership function instead of the trial-and-error approach. The MPPT algorithm is implemented in a new variant of coupled inductor soft switching boost converter with high voltage gain to increase the converter output from the PV panel. The applied switching technique, which includes passive and active regenerative snubber circuits, reduces the insulated gate bipolar transistor switching losses. The proposed MPPT algorithm is implemented using the dSPACE DS1104 platform software on a DS1104 board controller. The prototype MPPT controller is tested using an agilent solar array simulator together with a 3 kW real PV panel. Experimental test results show that the proposed boost converter produces higher output voltages and gives better efficiency (90% than the conventional boost converter with an RCD snubber, which gives 81% efficiency. The prototype MPPT controller is also found to be capable of tracking power from the 3 kW PV array about 2.4 times more than that without using the MPPT controller.

PV (photovoltaics) performance evaluation and simulation-based energy yield prediction for tropical buildings

International Nuclear Information System (INIS)

Saber, Esmail M.; Lee, Siew Eang; Manthapuri, Sumanth; Yi, Wang; Deb, Chirag

2014-01-01

Air pollution and climate change increased the importance of renewable energy resources like solar energy in the last decades. Rack-mounted PhotoVoltaics (PV) and Building Integrated PhotoVoltaics (BIPV) are the most common photovoltaic systems which convert incident solar radiation on façade or surrounding area to electricity. In this paper the performance of different solar cell types is evaluated for the tropical weather of Singapore. As a case study, on-site measured data of PV systems implemented in a zero energy building in Singapore, is analyzed. Different types of PV systems (silicon wafer and thin film) have been installed on rooftop, façade, car park shelter, railing and etc. The impact of different solar cell generations, arrays environmental conditions (no shading, dappled shading, full shading), orientation (South, North, East or West facing) and inclination (between PV module and horizontal direction) is investigated on performance of modules. In the second stage of research, the whole PV systems in the case study are simulated in EnergyPlus energy simulation software with several PV performance models including Simple, Equivalent one-diode and Sandia. The predicted results by different models are compared with measured data and the validated model is used to provide simulation-based energy yield predictions for wide ranges of scenarios. It has been concluded that orientation of low-slope rooftop PV has negligible impact on annual energy yield but in case of PV external sunshade, east façade and panel slope of 30–40° are the most suitable location and inclination. - Highlights: • Characteristics of PV systems in tropics are analyzed in depth. • The ambiguity toward amorphous panel energy yield in tropics is discussed. • Equivalent-one diode and Sandia models can fairly predict the energy yield. • A general guideline is provided to estimate the energy yield of PV systems in tropics

Energy self-sufficient micro systems using photovoltaics in buildings as an example; Energieautarke Mikrosysteme am Beispiel von Photovoltaik in Gebaeuden

Energy Technology Data Exchange (ETDEWEB)

Mueller, Monika

2010-07-01

The development of energy-optimized electronics with an average power consumption in the range of microwatts enabled the use of ambient energy to power these systems. This energy supply concept is also known as Micro Energy Harvesting. The main characteristics of these energy self-sufficient microsystems are low ambient power densities (microwatts per square centimeter) and an increased importance of higher-order terms in modeling the miniaturized energy converters. Furthermore, possible fields of application are heterogeneous. The range of the energy in the environment is several orders in magnitude. Thus, feasibility studies of regenerative microenergy sytems are bound to the surroundings of specific applications. This individuality raises the planning expenditure and complicates a systematical optimization and commercialization. This research study examines the general characteristic features of regenerative microsystems. The objective is to find modular and general descriptions of rising complexity instead of modeling single components for specialized applications. Thus, regenerative microsystems are treated comprising three main components, i.e. electric power consumption, ambient energy and energy converter. The types of power consumption are reduced into three main groups and the physical minima of required energies are discussed. Energy converters are analyzed in general. Radiant energy in buildings and photovoltaic energy conversion is analyzed analytically, numerically, and experimentally. Firstly, typical optic intensities in buildings are evaluated with radiometric methods. The use of raytracing programs for this application and the influence of user behaviour are examined. The study contains two rooms as well as different weather conditions and geographic positions. Measurements, simulations, and calculations are then carried out to investigate stationary electric light and dynamic solar radiation. A minimum radiation level of about 1-50 Wm{sup -2} is

Photovoltaic. Solar electricity, a sustainable source of energy

International Nuclear Information System (INIS)

Stryi-Hipp, Gerhard; Loyen, Richard; Knaack, Jan; Chrometzka, Thomas

2008-06-01

This German publication outlines that solar energy is now essential to any sustainable energy mix, and describes the operation principle of solar photovoltaic energy production. It describes how it can be applied for the production of electricity in isolated areas, and for individual housing as well as commercial buildings, and presents the concept of ground-based solar plants. The next part discusses the development of the photovoltaic market (its huge potential, its world size) and indicates the different associated arrangements of financial support or subsidy. It also discusses how photovoltaic markets can be developed, and proposes an overview of the German model

Solar thermal power and photovoltaic energy are both developing

International Nuclear Information System (INIS)

Le Jannic, N.; Houot, G.

2010-01-01

Thermodynamic solar energy and photovoltaic energy are expected to reach together a quarter of the world electricity production by 2050. In France the development of thermodynamic solar plants is hampered by the high cost of land in the sunny regions. As for photovoltaic energy, France has the potentiality to become an important producer. Since 2006, the French government has supported photovoltaic energy by proposing incentive electricity purchase prices guaranteed for 20 years. In 2006, the Ines research institute was founded, one of its research fields is the development of high yield silicon cells. (A.C.)

Solar spectrum conversion for photovoltaics using nanoparticles

OpenAIRE

Sark, W.G.J.H.M. van; Meijerink, A.; Schropp, R.E.I.

2012-01-01

The possibility to tune chemical and physical properties in nanosized materials has a strong impact on a variety of technologies, including photovoltaics. One of the prominent research areas of nanomaterials for photovoltaics involves spectral conversion. Conventional single-junction semiconductor solar cells only effectively convert photons of energy close to the semiconductor band gap (Eg) as a result of the mismatch between the incident solar spectrum and the spectral absorption properties...

Photovoltaic conversion of the solar energy

International Nuclear Information System (INIS)

Gordillo G, Gerardo

1998-01-01

In this work, a short description of the basic aspect of the performance of homojunction solar cells and of the technological aspects of the fabrication of low cost thin film solar cells is made. Special emphasis on the historical aspects of the evolution of the conversion efficiency of photovoltaic devices based on crystalline silicon, amorphous silicon, Cd Te and CulnSe 2 is also made. The state of art of the technology of photovoltaic devices and modules is additionally presented. The contribution to the development of high efficiency solar cells and modules, carried out by research centers of universities such us: Stuttgart university (Germany), Stockholm university (Sweden), University of South Florida (USA), university of south gales (Australia), by the national renewable energy laboratory of USA and by research centers of companies such us: Matsushita (Japan), BP-solar (England), Boeing (USA), Arco solar (USA), Siemens (Germany) etc. are specially emphasized. Additionally, a section concerning economical aspect of the photovoltaic generation of electric energy is enclosed. In this section an overview of the evolution of price and world market of photovoltaic system is presented

Standard Terminology Relating to Photovoltaic Solar Energy Conversion

CERN Document Server

American Society for Testing and Materials. Philadelphia

2005-01-01

1.1 This terminology pertains to photovoltaic (radiant-to-electrical energy conversion) device performance measurements and is not a comprehensive list of terminology for photovoltaics in general. 1.2 Additional terms used in this terminology and of interest to solar energy may be found in Terminology E 772.

Modularized multilevel and z-source power converter as renewable energy interface for vehicle and grid-connected applications

Science.gov (United States)

Cao, Dong

Due the energy crisis and increased oil price, renewable energy sources such as photovoltaic panel, wind turbine, or thermoelectric generation module, are used more and more widely for vehicle and grid-connected applications. However, the output of these renewable energy sources varies according to different solar radiation, wind speed, or temperature difference, a power converter interface is required for the vehicle or grid-connected applications. Thermoelectric generation (TEG) module as a renewable energy source for automotive industry is becoming very popular recently. Because of the inherent characteristics of TEG modules, a low input voltage, high input current and high voltage gain dc-dc converters are needed for the automotive load. Traditional high voltage gain dc-dc converters are not suitable for automotive application in terms of size and high temperature operation. Switched-capacitor dc-dc converters have to be used for this application. However, high voltage spike and EMI problems exist in traditional switched-capacitor dc-dc converters. Huge capacitor banks have to be utilized to reduce the voltage ripple and achieve high efficiency. A series of zero current switching (ZCS) or zero voltage switching switched-capacitor dc-dc converters have been proposed to overcome the aforementioned problems of the traditional switched-capacitor dc-dc converters. By using the proposed soft-switching strategy, high voltage spike is reduced, high EMI noise is restricted, and the huge capacitor bank is eliminated. High efficiency, high power density and high temperature switched-capacitor dc-dc converters could be made for the TEG interface in vehicle applications. Several prototypes have been made to validate the proposed circuit and confirm the circuit operation. In order to apply PV panel for grid-connected application, a low cost dc-ac inverter interface is required. From the use of transformer and safety concern, two different solutions can be implemented, non

Proposed electromagnetic wave energy converter

Science.gov (United States)

Bailey, R. L.

1973-01-01

Device converts wave energy into electric power through array of insulated absorber elements responsive to field of impinging electromagnetic radiation. Device could also serve as solar energy converter that is potentially less expensive and fragile than solar cells, yet substantially more efficient.

Photovoltaic solar energy

International Nuclear Information System (INIS)

Mouratoglou, P.; Therond, P.G.

2009-01-01

The most important assets of photovoltaic energy for sustainable development are its simplicity (no need for complicated thermodynamical cycles) and the universal availability of the sun which explains its great popularity. The main restraint to its full development is the high cost of the technologies used. The silicon technology is the historical technology, it has high conversion rates but is expensive because of high fabrication costs. This technology represents 80% of the market. On the other hand the thin film technology with CdTe, CIS or CIGS is promising in terms of costs but requires research works to increase its conversion rate. Japan and Germany are the leader countries in terms of photovoltaic for research, industrial fabrication or state support, they are followed by Spain, Usa, and China. (A.C.)

Enhancing the performance of photovoltaic cells by using down-converting KCaGd(PO4)2∶Eu3+ phosphors

Institute of Scientific and Technical Information of China (English)

Yen-Chi Chen; Woan-Yu Huang; Teng-Ming Chen

2011-01-01

The goal of this work is aimed to improve the power conversion efficiency of single crystalline silicon-based photovoltaic (PV) cells by using the solar spectral conversion principle,which employed a down-converting phosphor to convert a high-energy ultraviolet photon to the less energetic red-emitting photons to improve the spectral response of Si solar cells.In this study,the surface of silicon solar cells was coated with a red-emitting KCaGd(PO4)2∶Eu3+ phosphor by using the screen-printing technique.In addition to the investigation on the microstructure using scanning electron microscopy (SEM),we measured the short circuit current (Isc),open circuit voltage (Voc),and power conversion efficiency (η) of spectral-conversion cells and compared with those of bare solar cells as a reference.Preliminary experimental results revealed that in an optimized PV cell,an enhancement of (0.64+0.01)％ (from 16.03％ to 16.67％) in △η ofa Si-based PV cell was achieved.

A novel design of DC-AC electrical machine rotary converter for hybrid solar and wind energy applications

International Nuclear Information System (INIS)

Mohammed, K G; Ramli, A Q; Amirulddin, U A U

2013-01-01

This paper proposes the design of a new bi-directional DC-AC rotary converter machine to convert a d.c. voltage to three-phase voltage and vice-versa using a two-stage energy conversion machine. The rotary converter consists of two main stages which are combined into single frame. These two stages are constructed from three main electromagnetic components. The first inner electromagnetic component represents the input stage that enables the DC power generated by solar energy from photo-voltaic cells to be transformed by the second and third components electro-magnetically to produce multi-phase voltages at the output stage. At the same time, extra kinetic energy from wind, which is sufficiently available, can be added to existing torque on the second electromagnetic component. Both of these input energies will add up to the final energy generated at the output terminals. Therefore, the machine will be able to convert solar and wind energies to the output terminals simultaneously. If the solar energy is low, the available wind energy will be able to provide energy to the output terminals and at the same time charges the batteries which are connected as backup system. At this moment, the machine behaves as wind turbine. The energy output from the machine benefits from two energy sources which are solar and wind. At night when the solar energy is not available and also the load is low, the wind energy is able to charge the batteries and at the same time provides output electrical power to the remaining the load. Therefore, the proposed system will have high usage of available renewable energy as compared to separated wind or solar systems. MATLAB codes are used to calculate the required dimensions, the magnetic and electrical circuits parameters to design of the new bi-directional rotary converter machine.

The Role of Photovoltaics in Energy Requirements in Pakistan

International Nuclear Information System (INIS)

Shah, I.A.; Haq, N.U.; Nasir, H.

2011-01-01

In this review article global energy issue is discussed with specific reference to Pakistan. The energy consumption and supply from different sources like oil, gas, electricity, nuclear power, bio gas and especially from renewables is taken into account. Also discussed some suggestions for the energy requirements. Focus is given to the production of renewable energy sources like technology of photovoltaics in which solar power is converted into electricity. Solar cell is discussed including its two basic types inorganic solar cell and organic solar cell, its way of functioning, process of fabrication etc is also discussed. Organic or polymeric solar cell is discussed in detail. keeping in view the financial condition and requirement of energy for our country suggestions are given for low cost and simple processing of organic solar cells. It is also suggested that availability of all the materials required for the development of organic solar cells should be guaranteed. Interest should be developed at the university and other research organization level of Pakistan to do work on polymeric solar cells for increasing their efficiencies so that they can be practically utilized. (author)

MODELING SIMULATION AND PERFORMANCE STUDY OF GRIDCONNECTED PHOTOVOLTAIC ENERGY SYSTEM

OpenAIRE

Nagendra K; Karthik J; Keerthi Rao C; Kumar Raja Pemmadi

2017-01-01

This paper presents Modeling Simulation of grid connected Photovoltaic Energy System and performance study using MATLAB/Simulink. The Photovoltaic energy system is considered in three main parts PV Model, Power conditioning System and Grid interface. The Photovoltaic Model is inter-connected with grid through full scale power electronic devices. The simulation is conducted on the PV energy system at normal temperature and at constant load by using MATLAB.

Energy level alignment at interfaces in organic photovoltaic devices

International Nuclear Information System (INIS)

Opitz, Andreas; Frisch, Johannes; Schlesinger, Raphael; Wilke, Andreas; Koch, Norbert

2013-01-01

Highlights: ► Energy level alignment is crucial for organic solar cell efficiency. ► Photoelectron spectroscopy can reliably determine energy levels of organic material interfaces. ► Care must be taken to avoid even subtle sample damage. -- Abstract: The alignment of energy levels at interfaces in organic photovoltaic devices is crucial for their energy conversion efficiency. Photoelectron spectroscopy (PES) is a well-established and widely used technique for determining the electronic structure of materials; at the same time PES measurements of conjugated organic materials often pose significant challenges, such as obtaining sufficiently defined sample structures and radiation-induced damage of the organic layers. Here we report how these challenges can be tackled to unravel the energy levels at interfaces in organic photovoltaic devices, i.e., electrode/organic and organic/organic interfaces. The electronic structure across entire photovoltaic multilayer devices can thus be reconciled. Finally, general considerations for correlating the electronic structure and the photovoltaic performance of devices will be discussed

A Standalone Solar Photovoltaic Power Generation using Cuk Converter and Single Phase Inverter

Science.gov (United States)

Verma, A. K.; Singh, B.; Kaushika, S. C.

2013-03-01

In this paper, a standalone solar photovoltaic (SPV) power generating system is designed and modeled using a Cuk dc-dc converter and a single phase voltage source inverter (VSI). In this system, a dc-dc boost converter boosts a low voltage of a PV array to charge a battery at 24 V using a maximum power point tracking control algorithm. To step up a 24 V battery voltage to 360 V dc, a high frequency transformer based isolated dc-dc Cuk converter is used to reduce size, weight and losses. The dc voltage of 360 V is fed to a single phase VSI with unipolar switching to achieve a 230 Vrms, 50 Hz ac. The main objectives of this investigation are on efficiency improvement, reduction in cost, weight and size of the system and to provide an uninterruptible power to remotely located consumers. The complete SPV system is designed and it is modeled in MATLAB/Simulink. The simulated results are presented to demonstrate its satisfactory performance for validating the proposed design and control algorithm.

Improvement of Shade Resilience in Photovoltaic Modules Using Buck Converters in a Smart Module Architecture

Directory of Open Access Journals (Sweden)

S. Zahra Mirbagheri Golroodbari

2018-01-01

Full Text Available Partial shading has a nonlinear effect on the performance of photovoltaic (PV modules. Different methods of optimizing energy harvesting under partial shading conditions have been suggested to mitigate this issue. In this paper, a smart PV module architecture is proposed for improvement of shade resilience in a PV module consisting of 60 silicon solar cells, which compensates the current drops caused by partial shading. The architecture consists of groups of series-connected solar cells in parallel to a DC-DC buck converter. The number of cell groups is optimized with respect to cell and converter specifications using a least-squares support vector machine method. A generic model is developed to simulate the behavior of the smart architecture under different shading patterns, using high time resolution irradiance data. In this research the shading patterns are a combination of random and pole shadows. To investigate the shade resilience, results for the smart architecture are compared with an ideal module, and also ordinary series and parallel connected architectures. Although the annual yield for the smart architecture is 79.5% of the yield of an ideal module, we show that the smart architecture outperforms a standard series connected module by 47%, and a parallel architecture by 13.4%.

L-L multilevel boost converter topology for renewable energy applications

DEFF Research Database (Denmark)

Bhaskar, Mahajan Sagar; Padmanaban, Sanjeevikumar; Fedák, Viliam

2017-01-01

; such as a photovoltaic (PV) system with a Multilevel Inverter (MLI), electrical drives, automotive, hybrid electric cars etc. The proposed topology is derived by attaching the Cockcroft Walton (CW) multiplier to an upper L-converter of the LL topology of XY family. The mode of operation of L-LMBC with mathematical...

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 c...... 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.......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...

Towards Efficient Spectral Converters through Materials Design for Luminescent Solar Devices.

Science.gov (United States)

McKenna, Barry; Evans, Rachel C

2017-07-01

Single-junction photovoltaic devices exhibit a bottleneck in their efficiency due to incomplete or inefficient harvesting of photons in the low- or high-energy regions of the solar spectrum. Spectral converters can be used to convert solar photons into energies that are more effectively captured by the photovoltaic device through a photoluminescence process. Here, recent advances in the fields of luminescent solar concentration, luminescent downshifting, and upconversion are discussed. The focus is specifically on the role that materials science has to play in overcoming barriers in the optical performance in all spectral converters and on their successful integration with both established (e.g., c-Si, GaAs) and emerging (perovskite, organic, dye-sensitized) cell types. Current challenges and emerging research directions, which need to be addressed for the development of next-generation luminescent solar devices, are also discussed. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A Decision Model for Choosing Among Photovoltaic Technologies to Generate Electricity at Grid-Connected Air Force Facilities: A Value-Focused Approach

Science.gov (United States)

2006-03-01

goals, but it is also carries significant political interest. 1.1.4. Photovoltaic Effect A monocrystalline silicon photovoltaic cell (Figure 2) is...developed the industry by creating small photovoltaic panels to power watches and calculators (Archer, 2001; Wronski and Carlson, 2001). Amorphous silicon...Clinton, 1999). One particularly promising renewable energy source is solar energy converted to electricity by solar photovoltaic panels . Previous

Transformerless dc-Isolated Converter

Science.gov (United States)

Rippel, Wally E.

1987-01-01

Efficient voltage converter employs capacitive instead of transformer coupling to provide dc isolation. Offers buck/boost operation, minimal filtering, and low parts count, with possible application in photovoltaic power inverters, power supplies and battery charges. In photovoltaic inverter circuit with transformerless converter, Q2, Q3, Q4, and Q5 form line-commutated inverter. Switching losses and stresses nil because switching performed when current is zero.

Method for producing textured substrates for thin-film photovoltaic cells

Science.gov (United States)

Lauf, Robert J.

1994-01-01

The invention pertains to the production of ceramic substrates used in the manufacture of thin-film photovoltaic cells used for directly converting solar energy to electrical energy. Elongated ribbon-like sheets of substrate precursor containing a mixture of ceramic particulates, a binder, and a plasticizer are formed and then while green provided with a mechanically textured surface region used for supporting the thin film semiconductor of the photovoltaic cell when the sheets of the substrate precursor are subsequently cut into substrate-sized shapes and then sintered. The textured surface pattern on the substrate provides enhanced light trapping and collection for substantially increasing the solar energy conversion efficiency of thin-film photovoltaic cells.

Photovoltaic optimizer boost converters: Temperature influence and electro-thermal design

International Nuclear Information System (INIS)

Graditi, G.; Adinolfi, G.; Tina, G.M.

2014-01-01

Highlights: • The influence of temperature on DC–DC converter devices properties is considered. • An electro-thermal design method for PV power optimizer converters is proposed. • The electro-thermal design method proposed is applied to DR boost and SR boost. • Efficiency results of the designed SR converter and DR converters are presented. - Abstract: Objective: Photovoltaic (PV) systems can operate in presence of not uniform working conditions caused by continuously changing temperature and irradiance values and mismatching and shadowing phenomena. The more the PV system works in these conditions, the more its energy performances are negatively affected. Distributed Maximum Power Point Tracking (DMPPT) converters are now increasingly used to overcome this problem and to improve PV applications efficiency. A DMPPT system consists in a DC–DC converters equipped with a suitable controller dedicated to the Maximum Power Point Tracking (MPPT) of a single PV module. It is arranged either inside the junction-box or in a separate box close to the PV generator. Many power optimizers are now commercially available. In spite of different adopted DC–DC converter topologies, the shared interests of DMPPT systems designers are the high efficiency and reliability values. It is worth noting that to obtain so high performances converters, electronic components have to be carefully selected between the whole commercial availability and appropriately matched together. In this scenario, an electro-thermal design methodology is proposed and a reliability study by means of the Military Handbook 217F is carried out. Method: The developed DMPPT converters design method is constituted by many steps. In fact, beginning from installation site, PV generators and load data, this process selects power optimizers commercially available devices and it verifies their electro-thermal behavior to the aim to identify a set of suitable components for DMPPT applications. Repeating this

Comparing solar energy alternatives

Energy Technology Data Exchange (ETDEWEB)

White, J R

1984-01-01

The paper outlines a computational procedure for comparing the merits of alternative processes to convert solar radiation to heat, electrical power, or chemical energy. The procedure uses the ratio of equipment investment to useful work as an index. Comparisons with conversion counterparts based on conventional fuels are also facilitated by examining this index. The procedure is illustrated by comparisons of (1) photovoltaic converters of differing efficiencies; (2) photovoltaic converters with and without focusing concentrators; (3) photovoltaic conversion plus electrolysis vs photocatalysis for the production of hydrogen; (4) photovoltaic conversion plus plasma arcs vs photocatalysis for nitrogen fixation. Estimates for conventionally-fuelled processes are included for comparison. The reasons why solar-based concepts fare poorly in such comparisons are traced to the low energy density of solar radiation and its low stream time factor resulting from the limited number of daylight hours available and clouds obscuring the sun.

Comparing solar energy alternatives

Energy Technology Data Exchange (ETDEWEB)

White, J R

1984-01-01

This paper outlines a computational procedure for comparing the merits of alternative processes to convert solar radiation to heat, electrical power, or chemical energy. The procedure uses the ratio of equipment investment to useful work as an index. Comparisons with conversion counterparts based on conventional fuels are also facilitated by examining this index. The procedure is illustrated by comparisons of (1) photovoltaic converters of differing efficiencies; (2) photovoltaic converters with and without focusing concentrators; (3) photovoltaic conversion plus electrolysis vs photocatalysis for the production of hydrogen; (4) photovoltaic conversion plus plasma arcs vs photocatalysis for nitrogen fixation. Estimates for conventionally-fuelled processes are included for comparison. The reasons why solar-based concepts fare poorly in such comparisons are traced to the low energy density of solar radiation and its low stream time factor resulting from the limited number of daylight hours available and clouds obscuring the sun. 11 references.

Novel Interleaved Converter with Extra-High Voltage Gain to Process Low-Voltage Renewable-Energy Generation

Directory of Open Access Journals (Sweden)

Chih-Lung Shen

2016-10-01

Full Text Available This paper presents a novel interleaved converter (NIC with extra-high voltage gain to process the power of low-voltage renewable-energy generators such as photovoltaic (PV panel, wind turbine, and fuel cells. The NIC can boost a low input voltage to a much higher voltage level to inject renewable energy to DC bus for grid applications. Since the NIC has two circuit branches in parallel at frond end to share input current, it is suitable for high power applications. In addition, the NIC is controlled in an interleaving pattern, which has the advantages that the NIC has lower input current ripple, and the frequency of the ripple is twice the switching frequency. Two coupled inductors and two switched capacitors are incorporated to achieve a much higher voltage gain than conventional high step-up converters. The proposed NIC has intrinsic features such as leakage energy totally recycling and low voltage stress on power semiconductor. Thorough theoretical analysis and key parameter design are presented in this paper. A prototype is built for practical measurements to validate the proposed NIC.

Photovoltaic energy: an efficient development tool for Sub-Saharan economies

International Nuclear Information System (INIS)

Megherbi, Karim

2013-01-01

In this report, the author aims at highlighting the main success factors for a photovoltaic program in sub-Saharan Africa, and the benefits of this technology for African electricity operators. He first presents the electricity sector of Sub-Saharan Africa, its current situation, its scenarios of evolution, and the limitations of scenarios based on conventional energies. In a second part, he discusses the role photovoltaic solar energy could have within the energy mix of Sub-Saharan countries. He discusses how to calculate the cost of photovoltaic electricity production, and the value of photovoltaic electricity, discusses the main influencing parameters, and tries to identify when it becomes worth to choose photovoltaic electricity. He describes the implementation of an adapted legal and economic framework, the 'feed-in-tariff'. An appendix contains a proposition for Western Africa and analyses the case of Benin

The maximization of the efficiency in the energy conversion in isolated photovoltaic systems; Tecnicas de maxima transferencia de potencia em sistemas fotovoltaicos isolados

Energy Technology Data Exchange (ETDEWEB)

Machado-Neto, L. V. B.; Cabral, C. V. T.; Diniz, A. S. A. C.; Cortizo, P. C.; Oliveira-Filho, D.

2004-07-01

The maximization of the efficiency in the energy conversion is essential into the developing of technical and economic sustainability of photovoltaic solar energy systems. In this paper is realized the study of a power maximization technique for photovoltaic generators. The power maximization technique explored in this paper is the Maximum Power Point Tracking (MPPT). There are different strategies being studied currently; this work consists of the development of an electronic converter prototype for MPPT, including the developing of the tracking algorithm implemented in a microcontroller. It is also realized a simulation of the system and a prototype was assembled and the first results are presented here. (Author)

Asymmetrical Interleaved DC/DC Switching Converters for Photovoltaic and Fuel Cell Applications—Part 2: Control-Oriented Models

Directory of Open Access Journals (Sweden)

Sergio Ignacio Serna-Garces

2013-10-01

Full Text Available A previous article has presented the members of the asymmetrical interleaved dc/dc switching converters family as very appropriate candidates to interface between photovoltaic or fuel cell generators and their loads because of their reduced ripple and increased current processing capabilities. After a review of the main modeling methods suitable for high-order converters operating, as the asymmetrical interleaved converters (AIC ones, in discontinuous current conduction mode a full-order averaged model has been adapted and improved to describe the dynamic behavior of AIC. The excellent agreement between the mathematical model predictions, the switched simulations and the experimental results has allowed for satisfactory design of a linear-quadratic regulator (LQR in a fuel-cell application example, which demonstrates the usefulness of the improved control-oriented modeling approach when the switching converters operate in discontinuous conduction mode.

Underwater noise from a wave energy converter

DEFF Research Database (Denmark)

Tougaard, Jakob

A recent addition to the anthropogenic sources of underwater noise is offshore wave energy converters. Underwater noise was recorded from the Wavestar wave energy converter located at Hastholm, Denmark (57°7.73´N, 8°37.23´E). The Wavestar is a full-scale test and demonstration converter...... in full operation and start and stop of the converter. Median broad band (10 Hz – 20 kHz) sound pressure level (Leq) was 123 dB re. 1 Pa, irrespective of status of the wave energy converter (stopped, running or starting/stopping). The most pronounced peak in the third-octave spectrum was in the 160 Hz...... significant noise above ambient could be detected above the 250 Hz band. The absolute increase in noise above ambient was very small. L50 third-octave levels in the four bands with the converter running were thus only 1-2 dB above ambient L50 levels. The noise recorded 25 m from the wave energy converter...

Advanced Energy Validated Photovoltaic Inverter Technology at NREL | Energy

Science.gov (United States)

Inverter Technology at NREL Advanced Energy Industries-NREL's first partner at the Energy Systems Integration Facility (ESIF)-validated its advanced photovoltaic (PV) inverter technology using the ESIF's computer screen in a laboratory, with power inverter hardware in the background Photo by Dennis Schroeder

Energy Management and Simulation of Photovoltaic/Hydrogen /Battery Hybrid Power System

Directory of Open Access Journals (Sweden)

Tariq Kamal

2016-06-01

Full Text Available This manuscript focuses on a hybrid power system combining a solar photovoltaic array and energy storage system based on hydrogen technology (fuel cell, hydrogen tank and electrolyzer and battery. The complete architecture is connected to the national grid through power converters to increase the continuity of power. The proposed a hybrid power system is designed to work under classical-based energy management algorithm. According to the proposed algorithm, the PV has the priority in meeting the load demands. The hydrogen technology is utilized to ensure long-term energy balance. The battery is used as a backup and/or high power device to take care of the load following problems of hydrogen technology during transient. The dynamic performance of a hybrid power system is tested under different solar radiation, temperature and load conditions for the simulation of 24 Hrs. The effectiveness of the proposed system in terms of power sharing, grid stability, power quality and voltage regulation is verified by Matlab simulation results.

NASA-OAST program in photovoltaic energy conversion

Science.gov (United States)

Mullin, J. P.; Flood, D. J.

1982-01-01

The NASA program in photovoltaic energy conversion includes research and technology development efforts on solar cells, blankets, and arrays. The overall objectives are to increase conversion efficiency, reduce mass, reduce cost, and increase operating life. The potential growth of space power requirements in the future presents a major challenge to the current state of technology in space photovoltaic systems.

ANALYSIS OF THE ENERGY EFFICIENCY OF PHOTOVOLTAIC POLYCRYSTALLINE AND THIN-FILM PHOTOVOLTAIC FARM IN THE DOLINA ZIELAWY

Directory of Open Access Journals (Sweden)

Piotr Dragan

2016-12-01

Full Text Available Renewable energy is an opportunity not only to improve the energy efficiency of individual customers, but also to ensure energy security for local governments. In 2007, in Lublin province 5 municipalities have formed a partnership government called "Valley of Zielawa". The objectives of the partnership is the cooperation in the field of education, tasks in the field of culture, health protection, social welfare, fire protection and street lighting. One of the overarching goals of the partnership include ensure energy security and improving energy efficiency through the utilization of solar energy. Solar energy resources in the Lublin region are mainly characterized by a very high degree of sunlight compared to other regions of the country. The greatest potential for solar energy use is the eastern area of the province (including the area of partnership. In order to ensure the energy security of the community established a company Energy Valley of Zielawa, which in 2014 built a photovoltaic farm with a capacity of 1.4 MW in the Bordziłówka in Municipality Rossosz. This paper presents an analysis of photovoltaic farm work over the year and a half and the analysis of the energy efficiency of various types of photovoltaic panels which produce energy on a farm in photovoltaic Bordziłówce.

Controller for a wave energy converter

Science.gov (United States)

Wilson, David G.; Bull, Diana L.; Robinett, III, Rush D.

2015-09-22

A wave energy converter (WEC) is described, the WEC including a power take off (PTO) that converts relative motion of bodies of the WEC into electrical energy. A controller controls operation of the PTO, causing the PTO to act as a motor to widen a wave frequency spectrum that is usable to generate electrical energy.

Energy saved neon sign lighting power supply for photovoltaic systems

Energy Technology Data Exchange (ETDEWEB)

Tanitteerapan, T.; Dokpikul, S.; Arunrungrasmi, S. [King Mongkut Univ. of Technology Thonburi, Bangmod, Tungkru, Bangkok (Thailand). Dept. of Electrical Technology Education, Faculty of Industrial Education

2007-07-01

Petroleum oil, natural gas and fossil fuels are commonly used in power plants for electrical power generation. However, because of their negative environmental impacts, energy and environmental savings from renewable energy resources are necessary choices. Solar energy can be converted to the electrical voltage by using solar arrays. This process can be used in many electrical applications. This paper introduced a neon sign lighting power supply for a small photovoltaic powered stand-alone commercial advertising board for a remote area in Thailand. The circuit implementation was very simple, consisting of an active switch device, a resonant capacitor and high frequency transformer. The control also operated as a fixed frequency and fixed duty ratio controller. The paper discussed the principle of neon sign lighting, power circuit operation, and control circuit operation. To verify the proposed power supply, the circuit experiment of the proposed power supply for the neon sign lighting was applied to a 10 foot long, 10 millimeter diameter bulb. The neon sign was ignited smoothly with little power consumption. 2 refs., 1 tab., 10 figs.

Photovoltaic solar energy: which realities for 2020? Summarized synthesis

International Nuclear Information System (INIS)

2011-01-01

This report first describes the situation of the photovoltaic as situated at a crossroad with strong development possibilities for the French photovoltaic sector. It presents the photovoltaic energy as a competitive, regulatory and ecologic one, and therefore inescapable. It outlines stakes and obstacles of the French situation regarding the development of this sector. It highlights the economic and social benefit investing in this sector. Some propositions are stated for the promotion of the photovoltaic solar sector. Challenges are identified

Photovoltaic energy technologies: Health and environmental effects document

Science.gov (United States)

Moskowitz, P. D.; Hamilton, L. D.; Morris, S. C.; Rowe, M. D.

1980-09-01

The potential health and environmental consequences of producing electricity by photovoltaic energy systems was analyzed. Potential health and environmental risks are identified in representative fuel and material supply cycles including extraction, processing, refining, fabrication, installation, operation, and isposal for four photovoltaic energy systems (silicon N/P single crystal, silicon metal/insulator/semiconductor (MIS) cell, cadmium sulfide/copper sulfide backwall cell, and gallium arsenide heterojunction cell) delivering equal amounts of useful energy. Each step of the fuel and material supply cycles, materials demands, byproducts, public health, occupational health, and environmental hazards is identified.

CALCULATION OF OPERATING PARAMETERS OF HIGH-VOLTAGE POWER TAKE-OFF SYSTEM FOR THE PHOTOVOLTAIC FACILITY

Directory of Open Access Journals (Sweden)

R.V. Zaitsev

2016-09-01

Full Text Available Purpose. To ensure maximum production of electric power by photovoltaic vacilities, in addition to using highly efficient photovoltaic modules equipped with solar radiation concentrators must use a highly effective power take-off system. This paper is inscribed to solving the problem of a highly efficient and economic power take-off system development. Methodology. To solving the problem, we implemented three stages. On the first stage examines the dependence of electrical power from the intensity of the incident solar radiation. Based on this, the second stage is calculated the DC-DC converter resonant circuit and its working parameters, and developed circuit diagram of DC-DC converter. On the third stage, we carry out an analysis of power take-off system with step up DC-DC converter working. Results. In this paper, we carry out the analysis of working efficiency for photovoltaic facility power take-off system with step-up boost converter. The result of such analysis show that the efficiency of such system in a wide range of photovoltaic energy module illumination power is at 0.92, whereas the efficiency of classic power take-off systems does not exceed 0.70. Achieved results allow designing a circuit scheme of a controlled bridge resonant step-up converter with digital control. Proposed scheme will ensure reliable operation, fast and accurate location point of maximum power and conversion efficiency up to 0.96. Originality. Novelty of proposed power take-off system solution constitute in implementation of circuit with DC-DC converters, which as it shown by results of carrying out modeling is the most effective. Practical value. Practical implementation of proposed power take-off system design will allow reducing losses in connective wires and increasing the efficiency of such a system up to 92.5% in wide range of photovoltaic energy modules illumination.

Soft switching buck-boost converter for photovoltaic power generation; Taiyoko hatsuden no tame no soft switching shokoatsu converter

Energy Technology Data Exchange (ETDEWEB)

Lee, H. [Kyungnam University (Korea, Republic of)

1996-10-27

A soft switching method with small switching loss was proposed for the purpose of increasing the efficiency of a DC-DC boost converter which converted a DC current generated by solar cells to a variable DC current. Existing current converters are supplemented by using a snubber circuit around the switch so as to protect the switch by a hard switching action. However, with an increase of the output current, snubber loss is increased, reducing the efficiency. In order to solve this problem, the partial resonant switch method was applied to the converter; with this method of partially forming a resonant circuit only at the time of turning on/off of the switch, the switching loss was reduced through the soft switching, thereby making the proposed converter operate with high efficiency. Moreover, the resonant element of the partial resonant circuit using a snubber condenser, the energy accumulated in the condenser was regenerated on the power supply side without loss of snubber. With the regenerated energy, the proposed converter was provided with a smaller ratio of switching to use than the conventional converter. 4 refs., 7 figs., 1 tab.

Economical photovoltaic power generation with heat recovery

Science.gov (United States)

Ascher, G.

1977-01-01

Three designs for conversion of solar radiation to electricity and thermal energy are analyzed. The objective of these converters is to increase the electric and thermal output for each photovoltaic array so as to lower the cell cost relative to the amount of energy delivered. An analysis of the economical aspects of conversion by photovoltaic cells with heat recovery is carried out in terms of hypothetical examples. Thus, it is shown that the original cost of say $40,000 per generated kilowat can be reduced to $572.00 per kilowatt by increasing the original electric output of 1 kW to 10 kW in electricity and 60 kW in thermal energy. The newly derived specific cost is only 1.4 percent of the original one. It is expected that a cost reduction of roughly 2% of the present specific cost per kilowatt will greatly stimulate public acceptance of photovoltaic terrestrial conversion to electricity.

Nonlinear Dynamics and Bifurcation Analysis of a Boost Converter for Battery Charging in Photovoltaic Applications

Science.gov (United States)

Al-Hindawi, Mohammed M.; Abusorrah, Abdullah; Al-Turki, Yusuf; Giaouris, Damian; Mandal, Kuntal; Banerjee, Soumitro

Photovoltaic (PV) systems with a battery back-up form an integral part of distributed generation systems and therefore have recently attracted a lot of interest. In this paper, we consider a system of charging a battery from a PV panel through a current mode controlled boost dc-dc converter. We analyze its complete nonlinear/nonsmooth dynamics, using a piecewise model of the converter and realistic nonlinear v-i characteristics of the PV panel. Through this study, it is revealed that system design without taking into account the nonsmooth dynamics of the converter combined with the nonlinear v-i characteristics of the PV panel can lead to unpredictable responses of the overall system with high current ripple and other undesirable phenomena. This analysis can lead to better designed converters that can operate under a wide variation of the solar irradiation and the battery's state of charge. We show that the v-i characteristics of the PV panel combined with the battery's output voltage variation can increase or decrease the converter's robustness, both under peak current mode control and average current mode control. We justify the observation in terms of the change in the discrete-time map caused by the nonlinear v-i characteristics of the PV panel. The theoretical results are validated experimentally.

A Case Analysis of Energy Savings Performance Contract Projects and Photovoltaic Energy at Fort Bliss, El Paso, Texas

Science.gov (United States)

2006-06-01

PHOTOVOLTAIC ENERGY AND FORT BLISS CASE BACKGROUND A. PHOTOVOLTAIC ENERGY The use of photovoltaic power systems is nothing new in the Department...against the Outback MPPT charge controller . This test will be done over a one month timeframe. The Arizona Power ISG test plan is contained in...cost-benefit analysis of conventional power versus emerging photovoltaic energy for the Army’s Fort Bliss in El Paso, TX. The project will also analyze

Conference on new consumption and commercialization models for photovoltaic energy

International Nuclear Information System (INIS)

Freier, Karin; Fontaine, Pierre; Mayer, Joerg; Jimenez, Julien; Richard, Pascal; Vogtmann, Michael; Schaefer, Felix; Martin, Nicolas; Buis, Sabine

2014-01-01

The French-German office for Renewable energies (OFAEnR) organised a conference on new consumption and commercialization models for photovoltaic energy. In the framework of this French-German exchange of experience, about 120 participants exchanged views on the new economic models for solar energy producers while the photovoltaic industry has to face a progressive reduction of feed-in tariffs and of other incentive mechanisms. Beside the legal and economic aspects, technical questions around energy storage and integration of photovoltaic production to the grid were also addressed. This document brings together the available presentations (slides) made during this event: 1 - Stimulating self-consumption and direct selling within the EEG (Karin Freier); 2 - Development of PV self-consumption in France (Pierre Fontaine); 3 - experience from applying the new support program for solar energy storage systems (Joerg Mayer); 4 - Call for solar photovoltaic projects for own consumption in Aquitaine region (Julien Jimenez); 5 - SMA Flexible Storage System - New version of the Sunny Island inverter for smart photovoltaic energy storage (Pascal Richard); 6 - PV Own Consumption in industry and commerce - examples und Operating Concepts (Michael Vogtmann); 7 - Supplying tenants in multiple-family housing with solar power in the 'Neue Heimat' project (Felix Schaefer); 8 - How to manage PV-storage self-consumption from a grid point of view? (Nicolas Martin); 9 - Closing talk (Sabine Buis)

NASA-OAST photovoltaic energy conversion program

Science.gov (United States)

Mullin, J. P.; Loria, J. C.

1984-01-01

The NASA program in photovoltaic energy conversion research is discussed. Solar cells, solar arrays, gallium arsenides, space station and spacecraft power supplies, and state of the art devices are discussed.

Optimization of structural and growth parameters of metamorphic InGaAs photovoltaic converters grown by MOCVD

Energy Technology Data Exchange (ETDEWEB)

Rybalchenko, D. V.; Mintairov, S. A.; Salii, R. A.; Shvarts, M. Z.; Timoshina, N. Kh.; Kalyuzhnyy, N. A., E-mail: nickk@mail.ioffe.ru [Russian Academy of Sciences, Ioffe Physical–Technical Institute (Russian Federation)

2017-01-15

Metamorphic Ga{sub 0.76}In{sub 0.24}As heterostructures for photovoltaic converters are grown by the MOCVD (metal–organic chemical vapor deposition) technique. It is found that, due to the valence-band offset at the p-In{sub 0.24}Al{sub 0.76}As/p-In{sub 0.24}Ga{sub 0.76}As (wide-gap window/emitter) heterointerface, a potential barrier for holes arises as a result of a low carrier concentration in the wide-gap material. The use of an InAlGaAs solid solution with an Al content lower than 40% makes it possible to raise the hole concentration in the widegap window up ~9 × 10{sup 18} cm{sup –3} and completely remove the potential barrier, thereby reducing the series resistance of the device. The parameters of an GaInAs metamorphic buffer layer with a stepwise In content profile are calculated and its epitaxial growth conditions are optimized, which improves carrier collection from the n-GaInAs base region and provides a quantum efficiency of 83% at a wavelength of 1064 nm. Optimization of the metamorphic heterostructure of the photovoltaic converter results in that its conversion efficiency for laser light with a wavelength of 1064 nm is 38.5%.

Solar energy photovoltaic technology: proficiency and performance; L'energie solaire maitrise et performance photovoltaiques

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-07-01

Total is committed to making the best possible of the planet's fossil fuel reserves while fostering the emergence of other solutions, notably by developing effective alternatives. Total involves in photovoltaics when it founded in 1983 Total Energies, renamed Tenesol in 2005, a world leader in the design and installation of photovoltaic solar power systems. This document presents Total's activities in the domain: the global challenge of energy sources and the environment, the energy collecting by photovoltaic electricity, the silicon technology for cell production, solar panels and systems to distribute energy, research and development to secure the future. (A.L.B.)

Ocean floor mounting of wave energy converters

Science.gov (United States)

Siegel, Stefan G

2015-01-20

A system for mounting a set of wave energy converters in the ocean includes a pole attached to a floor of an ocean and a slider mounted on the pole in a manner that permits the slider to move vertically along the pole and rotate about the pole. The wave energy converters can then be mounted on the slider to allow adjustment of the depth and orientation of the wave energy converters.

Neural Modeling of Fuzzy Controllers for Maximum Power Point Tracking in Photovoltaic Energy Systems

Science.gov (United States)

Lopez-Guede, Jose Manuel; Ramos-Hernanz, Josean; Altın, Necmi; Ozdemir, Saban; Kurt, Erol; Azkune, Gorka

2018-06-01

One field in which electronic materials have an important role is energy generation, especially within the scope of photovoltaic energy. This paper deals with one of the most relevant enabling technologies within that scope, i.e, the algorithms for maximum power point tracking implemented in the direct current to direct current converters and its modeling through artificial neural networks (ANNs). More specifically, as a proof of concept, we have addressed the problem of modeling a fuzzy logic controller that has shown its performance in previous works, and more specifically the dimensionless duty cycle signal that controls a quadratic boost converter. We achieved a very accurate model since the obtained medium squared error is 3.47 × 10-6, the maximum error is 16.32 × 10-3 and the regression coefficient R is 0.99992, all for the test dataset. This neural implementation has obvious advantages such as a higher fault tolerance and a simpler implementation, dispensing with all the complex elements needed to run a fuzzy controller (fuzzifier, defuzzifier, inference engine and knowledge base) because, ultimately, ANNs are sums and products.

Photovoltaic: Instructional Manual. The North Dakota High Technology Mobile Laboratory Project.

Science.gov (United States)

Auer, Herbert J.

This instructional manual contains 11 learning activity packets for use in a workshop on photovoltaic converters. The lessons cover the following topics: introduction; solar radiation--input for photovoltaic converters; photovoltaic cells; solar electric generator systems; characteristics of silicon cells; photovoltaic module source resistance;…

Japan, world leader of photovoltaic energy

International Nuclear Information System (INIS)

Strasser, F.

2006-01-01

Since the beginning of the 1970's, the potentialities of photovoltaic energy has been recognized by the Japanese government which has sustained this technology in two ways. First, by the financing of R and D programs, and second, by giving subsidies to citizens for the installation of solar panels. Today, Japan is the world leader of photovoltaic energy, both for the installed power and for the production of solar cells. In 2003, the International Energy Agency was reporting 1.809 GW of worldwide installed capacity among which 48% was in Japan (0.86 GW) with respect to 0.4 GW in Germany, 0.275 GW in the USA and only 20 MW in France. This capacity would have exceeded 1.1 GW at the end of 2004. Half of the solar modules are manufactured in Japan. The ministry of economy, trade and industry (METI) has fixed ambitious goals for 2010: the overall new energy sources much represent 3% of the primary energy (with respect to 1% today) and the installed capacity must reach 4.8 GW. The road-map of the New Energy and Industrial Technology Development Organisation (NEDO) foresees 100 GW by 2030. (J.S.)

Photovoltaic energy in power market

NARCIS (Netherlands)

Ho, D.T.; Frunt, J.; Myrzik, J.M.A.

2009-01-01

Photovoltaic (PV) penetration in the grid connected power system has been growing. Currently, PV electricity is usually directly sold back to the energy supplier at a fixed price and subsidy. However, subsidies should always be a temporary policy, and will eventually be terminated. A question is

A new configuration for multilevel converters with diode clamped topology

DEFF Research Database (Denmark)

Nami, A.; Zare, F.; Ledwich, G.

2008-01-01

Due to the increased use of renewable energy and power elctronic applications, more multilevel converters (MLC) are developed. A Neutral Point Clamped (NPC) inverter is one of the most used multilevel topologies for wind turbine (WT) and photovoltaic (PV) applications. One of the most crucial...... of load changes which can avoid neutral point balancing problem in such converters. In addition, the presented topology is suitable for renewable energy systems to boost the low rectified output-voltage. In order to verify the proposed topology, steady state analysis, modelling and simulations are carried...

Photovoltaics as a worldwide energy source

International Nuclear Information System (INIS)

Jones, G.J.

1991-01-01

Photovoltaic energy systems have historically been treated as a bulk power generation source for the future. However, utilities and other agencies involved with electrification throughout the world are beginning to find photovoltaics a least-cost option to meet specific loads both for themselves and their customers, in both off-grid and grid-connected applications. These expanding markets offer the potential of hundreds of megawatts of sales in the coming decade, but a strategy addressing both industrial growth and user acceptance is necessary to capitalize on this opportunity. 11 refs

Photovoltaic solar energy. Proceedings; Photovoltaische Solarenergie. Tagungsband

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-07-01

Within the 21st symposium 'Photovoltaic Solar Energy' of the Ostbayerisches Technologie-Transfer-Institut e.V. (Regensburg, Federal Republic of Germany) at Banz Monastery (Bad Staffelstein, Federal Republic of Germany) between 8th and 10th March, 2006, the following lessons were held: (1) Basic conditions for a market support programme in the European context (EEG) (Winfried Hoffmann); (2) Actual developments in the German market of photovoltaics (Gerhard Stryi-Hipp); (3) Become a part of the global economic survey of Task 2 ''PV cost over time'' (Thomas Nordmann); (4) The market of photovoltaic will be a European market in the future (Murray Cameron); (5) Development and state of the art of the photovoltaic industry in the Peoples Republic of China (Frank Haugwitz); (6) Silicon for the photovoltaic industry (Karl Hesse); (7) Cell technology: Impulses for a cost effective photovoltaic with valuable silicon (Rolf Brendel); (8) Thin-film solar modules for the photovoltaic - state of the art and industrial perspectives (Michael Powalla); (9) Modules - bottleneck and flood of orders: How to act an installer? (Helmut Godard); (10) Photovoltaic open-field systems - Actual experiences and conflict lines (Ole Langniss); (11) Comparison of actual and future trends of Balance-of-System costs for large scale ground based PV systems with crystalline and thin-film modules (Manfred Baechler); (12) Financing PX projects from a Bank perspective (Joachim Treder); (13) Criteria of quality for solar fonds - Criteria of evaluation for capital investors and self-commitment for emission houses (Ulla Meixner); (14) Analysis of the distribution pathways for photovoltaic plants from the manufacturer to the final customer considering the decreasing demand and increasing prices (Michael Forst); (15) Solar power 2005 - Evaluation of real operational data of 1,000 plants in Germany (Gerd Heilscher); (16) Improvement of PV-inverter efficiency - targets, pathways

High-Efficiency High Step-Up DC-DC Converter with Dual Coupled Inductors for Grid-Connected Photovoltaic Systems

DEFF Research Database (Denmark)

Forouzesh, Mojtaba; Shen, Yanfeng; Siwakoti, Yam Prasad

2018-01-01

with a common ground connection of the input and output make the proposed topology a proper candidate for a transformer-less grid connected photovoltaic systems. The operating performance, analysis and mathematical derivations of the proposed dc-dc converter have been demonstrated in the paper. Moreover......This paper introduces a non-isolated high step-up dc-dc converter with dual coupled inductors suitable for distributed generation applications. By implementing an input parallel connection, the proposed dc-dc structure inherits shared input current with low ripple, which also requires small...... capacitive filter at its input. Moreover, this topology can reach high voltage gain by using dual coupled inductors in series connection at the output stage. The proposed converter uses active clamp circuits with a shared clamp capacitor for the main switches. In addition to the active clamp circuit...

Photovoltaic energy barometer

International Nuclear Information System (INIS)

Anon.

2007-01-01

The european photovoltaic market once again reached the heights in 2006, thanks to the dynamism of the German market. White paper objectives have thus been fulfilled four years ahead of schedule. The european photovoltaic sector remains however very heterogeneous with both an ultra-dominant German market (estimated at 1150 MWp in 2006) and other countries of the European Union that vary from a few kWP to a few dozen MWp. This analysis provides statistical data on the market, the capacity installed during 2005 and 2006, the photovoltaic parks and the evolution of the photovoltaic cell production. (A.L.B.)

Applied research on energy storage and conversion for photovoltaic and wind energy systems. Volume II. Photovoltaic systems with energy storage. Final report

Energy Technology Data Exchange (ETDEWEB)

1978-01-01

This volume of the General Electric study was directed at an evaluation of those energy storage technologies deemed best suited for use in conjunction with a photovoltaic energy conversion system in utility, residential and intermediate applications. Break-even cost goals are developed for several storage technologies in each application. These break-even costs are then compared with cost projections presented in Volume I of this report to show technologies and time frames of potential economic viability. The form of the presentation allows the reader to use more accurate storage system cost data as they become available. The report summarizes the investigations performed and presents the results, conclusions and recommendations pertaining to use of energy storage with photovoltaic energy conversion systems. Candidate storage concepts studied include (1) above ground and underground pumped hydro, (2) underground compressed air, (3) electric batteries, (4) flywheels, and (5) hydrogen production and storage. (WHK)

Projected photovoltaic energy impacts on US CO2 emissions: an integrated energy environmental-economic analysis

International Nuclear Information System (INIS)

Lee, J.C.; Fthenakis, V.M.; Morris, S.C.; Goldstein, G.A.; Moskowitz, P.D.

1997-01-01

The potential role of photovoltaic technologies in reducing carbon dioxide (CO 2 ) emissions in the USA was evaluated using an energy-environment-economic systems model. With a range of assumptions about future scenarios up to 2030, the model results provide an objective quantitative assessment of the prospects for photovoltaics in a competitive market. With the projected improvements in cost and efficiency, photovoltaics will compete favourably as a general source of electricity supply to the grid by about 2010 in southwestern USA. This analysis indicates that photovoltaics has the potential to reach a total installed capacity of 140 GW by the year 2030, and to displace a cumulative 450 million metric tons of carbon emissions from 1995 to 2030. At the projected 2030 capacity, photovoltaics could displace over 64 million metric tons of carbon emissions a year. Under constraints on carbon emissions, photovoltaics becomes more cost effective and would further reduce carbon emissions from the US energy system. (author)

Resonant Wave Energy Converters: Concept development

International Nuclear Information System (INIS)

Arena, Felice; Barbaro, Giuseppe; Fiamma, Vincenzo; Laface, Valentina; Malara, Giovanni; Romolo, Alessandra; Strati, Federica Mara

2015-01-01

The Resonant Wave Energy Converter (REWEC) is a device for converting sea wave energy to electrical energy. It belongs to the family of Oscillating Water Columns and is composed by an absorbing chamber connected to the open sea via a vertical duct. The paper gives a holistic view on the concept development of the device, starting from its implementation in the context of submerged breakwaters to the recently developed vertical breakwaters. [it

An Optimal Control Strategy for DC Bus Voltage Regulation in Photovoltaic System with Battery Energy Storage

Directory of Open Access Journals (Sweden)

Muhamad Zalani Daud

2014-01-01

Full Text Available This paper presents an evaluation of an optimal DC bus voltage regulation strategy for grid-connected photovoltaic (PV system with battery energy storage (BES. The BES is connected to the PV system DC bus using a DC/DC buck-boost converter. The converter facilitates the BES power charge/discharge to compensate for the DC bus voltage deviation during severe disturbance conditions. In this way, the regulation of DC bus voltage of the PV/BES system can be enhanced as compared to the conventional regulation that is solely based on the voltage-sourced converter (VSC. For the grid side VSC (G-VSC, two control methods, namely, the voltage-mode and current-mode controls, are applied. For control parameter optimization, the simplex optimization technique is applied for the G-VSC voltage- and current-mode controls, including the BES DC/DC buck-boost converter controllers. A new set of optimized parameters are obtained for each of the power converters for comparison purposes. The PSCAD/EMTDC-based simulation case studies are presented to evaluate the performance of the proposed optimized control scheme in comparison to the conventional methods.

An optimal control strategy for DC bus voltage regulation in photovoltaic system with battery energy storage.

Science.gov (United States)

Daud, Muhamad Zalani; Mohamed, Azah; Hannan, M A

2014-01-01

This paper presents an evaluation of an optimal DC bus voltage regulation strategy for grid-connected photovoltaic (PV) system with battery energy storage (BES). The BES is connected to the PV system DC bus using a DC/DC buck-boost converter. The converter facilitates the BES power charge/discharge to compensate for the DC bus voltage deviation during severe disturbance conditions. In this way, the regulation of DC bus voltage of the PV/BES system can be enhanced as compared to the conventional regulation that is solely based on the voltage-sourced converter (VSC). For the grid side VSC (G-VSC), two control methods, namely, the voltage-mode and current-mode controls, are applied. For control parameter optimization, the simplex optimization technique is applied for the G-VSC voltage- and current-mode controls, including the BES DC/DC buck-boost converter controllers. A new set of optimized parameters are obtained for each of the power converters for comparison purposes. The PSCAD/EMTDC-based simulation case studies are presented to evaluate the performance of the proposed optimized control scheme in comparison to the conventional methods.

Energy Return on Energy Invested (ERoEI) for photovoltaic solar systems in regions of moderate insolation

International Nuclear Information System (INIS)

Ferroni, Ferruccio; Hopkirk, Robert J.

2016-01-01

Many people believe renewable energy sources to be capable of substituting fossil or nuclear energy. However there exist very few scientifically sound studies, which apply due diligence to substantiating this impression. In the present paper, the case of photovoltaic power sources in regions of moderate insolation is analysed critically by using the concept of Energy Return on Energy Invested (ERoEI, also called EROI). But the methodology for calculating the ERoEI differs greatly from author-to-author. The main differences between solar PV Systems are between the current ERoEI and what is called the extended ERoEI (ERoEI EXT ). The current methodology recommended by the International Energy Agency is not strictly applicable for comparing photovoltaic (PV) power generation with other systems. The main reasons are due to the fact that on one hand, solar electricity is very material-intensive, labour-intensive and capital-intensive and on the other hand the solar radiation exhibits a rather low power density. - Highlights: •Data are available from several years of photovoltaic energy experience in northern Europe. •These are used to show the way to calculate a full, extended ERoEI. •The viability and sustainability in these latitudes of photovoltaic energy is questioned. •Use of photovoltaic technology is shown to result in creation of an energy sink.

From low cost to high tech: possible margins of technical progress in photovoltaic

International Nuclear Information System (INIS)

Guillemoles, J.F.

2009-01-01

Photovoltaic is developing in response to 3 requirements: conservation of the environment, security in energy, and economic growth. Given this, the terawatt (TW) scale should be used to measure the magnitude of energy needs. Can solar, in particular photovoltaic, power meet these needs? This has nothing to do with the availability of solar energy - in a single hour, the sun sends to the earth as much energy as the electricity consumed by all of humanity during an entire year. Instead, it raises questions about the industrial deployment and, eventually, the availability of raw materials and land. The sustainable development of photovoltaic power implies wisely using resources (raw materials, energy and capital) and improving the efficiency not only of the process for transforming resources into photovoltaic units but also of the photovoltaic units themselves for converting light into electricity. It is worth noting that the predictable change of scale in the photovoltaic industry will have implications for this industry's deployment on a large scale. This deployment depends on: the availability of technology, know-how, capital and raw materials; the cost of investments; the speed of implementation; and the rhythm of production of cells. (author)

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

A dynamic model of a photovoltaic vapour compression system

International Nuclear Information System (INIS)

Renno, C.

2009-01-01

A dynamic simulation of a photovoltaic vapour compression system is presented in this paper. In particular, there are several options to convert solar energy into refrigeration effect such as the absorption cycle, the thermo-mechanical refrigeration systems, the regenerative desiccant process or the steam jet system. This effect can also be produced by a conventional vapor compression cycle in which the compressor is driven by an electric motor supplied by means of photovoltaic cells. It is also possible to produce the cooling effect adopting the thermoelectric refrigeration, with electricity supplied by means of photovoltaic cells. Absorption and solar mechanical systems are necessarily larger and require extensive plumbing and electrical connections. The dynamic model allows to obtain some characteristic temperatures of the photovoltaic system and the energy consumptions with and without load perturbations. This model results a useful tool to study the dynamic working, for example, of photovoltaic refrigerators used in rural areas and remote islands, for their simple structure and low costs, to preserve foodstuffs, vaccines and other life saving medicines. (author)

Comparison of zero-sequence injection methods in cascaded H-bridge multilevel converters for large-scale photovoltaic integration

DEFF Research Database (Denmark)

Yu, Yifan; Konstantinou, Georgios; Townsend, Christopher David

2017-01-01

to maintain three-phase balanced grid currents with unbalanced power generation. This study theoretically compares power balance capabilities of various zero-sequence injection methods based on two metrics which can be easily generalised for all CHB applications to PV systems. Experimental results based......Photovoltaic (PV) power generation levels in the three phases of a multilevel cascaded H-bridge (CHB) converter can be significantly unbalanced, owing to different irradiance levels and ambient temperatures over a large-scale solar PV power plant. Injection of a zero-sequence voltage is required...... on a 430 V, 10 kW, three-phase, seven-level cascaded H-bridge converter prototype confirm superior performance of the optimal zero-sequence injection technique....

The characteristic analysis of the solar energy photovoltaic power generation system

Science.gov (United States)

Liu, B.; Li, K.; Niu, D. D.; Jin, Y. A.; Liu, Y.

2017-01-01

Solar energy is an inexhaustible, clean, renewable energy source. Photovoltaic cells are a key component in solar power generation, so thorough research on output characteristics is of far-reaching importance. In this paper, an illumination model and a photovoltaic power station output power model were established, and simulation analysis was conducted using Matlab and other software. The analysis evaluated the condition of solar energy resources in the Baicheng region in the western part of Jilin province, China. The characteristic curve of the power output from a photovoltaic power station was obtained by simulation calculation. It was shown that the monthly average output power of the photovoltaic power station is affected by seasonal changes; the output power is higher in summer and autumn, and lower in spring and winter.

Maximum power point tracker for photovoltaic power plants

Science.gov (United States)

Arcidiacono, V.; Corsi, S.; Lambri, L.

The paper describes two different closed-loop control criteria for the maximum power point tracking of the voltage-current characteristic of a photovoltaic generator. The two criteria are discussed and compared, inter alia, with regard to the setting-up problems that they pose. Although a detailed analysis is not embarked upon, the paper also provides some quantitative information on the energy advantages obtained by using electronic maximum power point tracking systems, as compared with the situation in which the point of operation of the photovoltaic generator is not controlled at all. Lastly, the paper presents two high-efficiency MPPT converters for experimental photovoltaic plants of the stand-alone and the grid-interconnected type.

Energy efficiency of a photovoltaic cell based thin films CZTS by ...

African Journals Online (AJOL)

Energy efficiency of a photovoltaic cell based thin films CZTS by SCAPS. ... use of natural resources, the use of renewable energy including solar photovoltaic ... η for typical structures of ZnO / i- ZnO / CdS / CZTS and ITO / ZnO / CdS / CZTS.

Photovoltaic Solar Energy : From Fundamentals to Applications

NARCIS (Netherlands)

Reinders, Angelina H.M.E.; Verlinden, P.J.; van Sark, W.G.J.H.M.; Freundlich, A.

2016-01-01

Solar PV is now the third most important renewable energy source, after hydro and wind power, in terms of global installed capacity. Bringing together the expertise of international PV specialists Photovoltaic Solar Energy: From Fundamentals to Applications provides a comprehensive and up-to-date

Model Predictive Control of Grid Connected Modular Multilevel Converter for Integration of Photovoltaic Power Systems

DEFF Research Database (Denmark)

Hajizadeh, Amin; Shahirinia, Amir

2017-01-01

Investigation of an advanced control structure for integration of Photovoltaic Power Systems through Grid Connected-Modular Multilevel Converter (GC-MMC) is proposed in this paper. To achieve this goal, a non-linear model of MMC regarding considering of negative and positive sequence components has...... been presented. Then, due to existence of unbalance voltage faults in distribution grid, non-linarites and uncertainties in model, model predictive controller which is developed for GC-MMC. They are implemented based upon positive and negative components of voltage and current to mitigate the power...

Photovoltaics at Point Pelee Park

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-12-01

Case study of an Ontario Hydro-installed photovoltaic system at Point Pelee Park, a bird sanctuary located on Lake Erie, is described. The system consists of a 1080 W photovoltaic array used to supply electricity to one of the washrooms. The cost for installing the system was $30,000 which was considerably cheaper than the $100,000 estimate for an underground power line. The independent system is the only source of energy for the washroom, therefore it was necessary to reduce the total electrical demand required by the facility. Electricity was used for the water pump, chlorinator and lighting. Motion sensors were installed to further reduce electrical demand. Washroom heaters were converted to propane. 2 figs.

You're a What? Solar Photovoltaic Installer

Science.gov (United States)

Torpey, Elka Maria

2009-01-01

This article talks about solar photovoltaic (PV) installer and features Rebekah Hren, a solar PV installer who puts solar panels on roofs and in other sunny places to turn the sun's power into electricity. Hren enjoys promoting renewable energy, in part because it's an emerging field. In solar PV systems, solar cells--devices that convert sunlight…

Expected energy production evaluation for photovoltaic systems

DEFF Research Database (Denmark)

Ding, Yi; Østergaard, Jacob; Peng, Wang

2011-01-01

A photovoltaic (PV) system consists of many solar panels, which are connected in series, parallel or a combination of both. Energy production for the PV system with various configurations is different. In this paper, a methodology is developed to evaluate and analyze the expected energy production...

Parametric pendulum based wave energy converter

Science.gov (United States)

Yurchenko, Daniil; Alevras, Panagiotis

2018-01-01

The paper investigates the dynamics of a novel wave energy converter based on the parametrically excited pendulum. The herein developed concept of the parametric pendulum allows reducing the influence of the gravity force thereby significantly improving the device performance at a regular sea state, which could not be achieved in the earlier proposed original point-absorber design. The suggested design of a wave energy converter achieves a dominant rotational motion without any additional mechanisms, like a gearbox, or any active control involvement. Presented numerical results of deterministic and stochastic modeling clearly reflect the advantage of the proposed design. A set of experimental results confirms the numerical findings and validates the new design of a parametric pendulum based wave energy converter. Power harvesting potential of the novel device is also presented.

New Multiphase Hybrid Boost Converter with Wide Conversion Ratio for PV System

Directory of Open Access Journals (Sweden)

Ioana-Monica Pop-Calimanu

2014-01-01

Full Text Available A new multiphase hybrid boost converter, with wide conversion ratio as a solution for photovoltaic energy system, is presented in this paper. To ensure that all the phases of the converter operate at the same switching frequency we use interleaving topology. The proposed converter can be used as an interface between the PV system and the DC load/inverter. This multiphase converter has the advantage of reduced value and physical size of the input and output capacitor as well as the effort for the inductors. To validate the operation of the converter we provide the analyses and the simulation results of the converter.

The Effects of Cells Temperature Increment and Variations of Irradiation for Monocrystalline Photovoltaic

Science.gov (United States)

Fuad Rahman Soeharto, Faishal; Hermawan

2017-04-01

Photovoltaic cell technology has been developed to meet the target of 17% Renewable Energy in 2025 accordance with Indonesia Government Regulation No. 5 2006. Photovoltaic cells are made of semiconductor materials, namely silicon or germanium (p-n junction). These cells need the light that comes from solar irradiation which brings energy photons to convert light energy into electrical energy. It is different from the solar heater that requires heat energy or thermal of sunlight that is normally used for drying or heating water. Photovoltaic cells requires energy photons to perform the energy conversion process, the photon energy can be derived from sunlight. Energy photon is taken from the sun light along with the advent of heat due to black-body radiation, which can lead to temperature increments of photovoltaic cells. Increment of 1°C can decreased photovoltaic cell voltage of up to 2.3 mV per cell. In this research, it will be discuss the analysis of the effect of rising temperatures and variations of irradiation on the type monocrystalline photovoltaic. Those variation are analyzed, simulated and experiment by using a module of experiment. The test results show that increment temperature from 25° C to 80° C at cell of photovoltaic decrease the output voltage of the photovoltaic cell at 4.21 V, and it also affect the power output of the cell which decreases up to 0.7523 Watt. In addition, the bigger the value of irradiation received by cell at amount of 1000 W / m2, produce more output power cells at the same temperature.

Power Converters Maximize Outputs Of Solar Cell Strings

Science.gov (United States)

Frederick, Martin E.; Jermakian, Joel B.

1993-01-01

Microprocessor-controlled dc-to-dc power converters devised to maximize power transferred from solar photovoltaic strings to storage batteries and other electrical loads. Converters help in utilizing large solar photovoltaic arrays most effectively with respect to cost, size, and weight. Main points of invention are: single controller used to control and optimize any number of "dumb" tracker units and strings independently; power maximized out of converters; and controller in system is microprocessor.

Presentations given at the Enerplan Conference: facilitating photovoltaic energy integration in the grid

International Nuclear Information System (INIS)

Mueth, Thierry; Thomas, Christophe; Loyen, Richard; Masson, Gaetan; Najdawi, Celine; Dubus, Jean-Michel; Carre, Olivier; Resseguier, Stephane de; Alazard, Raymond; Prest, Ignace de; Humez, Herve; Kaiser, Martin; Cassagne, Valerick; Dauphin, Francois; Merley, Jacques; Laffaille, Didier; Gossement, Arnaud; Belon, Daniel; Blanquet, Francois; Bonnet, Jean-Philippe; Sanchez, Louis; Vienot, Raphaelle; Lambert, Karine; Berly, Frederic

2013-07-01

Large-scale integration of photovoltaic energy in power grids are present day topics of strategical stakes for the development of the photovoltaic industry and for the success of the energy transition. This conference provided some answers to three main subjects which were the main themes of the 3 round-tables: 1 - Identifying the context elements leading to a large integration of solar energy in Europe and in France; 2 - Identifying the technical solutions facilitating the technical integration of photovoltaic energy in power grids; 3 - Analysing the expected regional schemes for connecting renewable energies to the network, in order to shift from an administrative planning to a dynamical and practical approach profitable to the photovoltaic industry. This document brings together the available presentations (slides) given at the colloquium

Vectorial Command of Induction Motor Pumping System Supplied by a Photovoltaic Generator

Science.gov (United States)

Makhlouf, Messaoud; Messai, Feyrouz; Benalla, Hocine

2011-01-01

With the continuous decrease of the cost of solar cells, there is an increasing interest and needs in photovoltaic (PV) system applications following standard of living improvements. Water pumping system powered by solar-cell generators are one of the most important applications. The fluctuation of solar energy on one hand, and the necessity to optimise available solar energy on the other, it is useful to develop new efficient and flexible modes to control motors that entrain the pump. A vectorial control of an asynchronous motor fed by a photovoltaic system is proposed. This paper investigates a photovoltaic-electro mechanic chain, composed of a PV generator, DC-AC converter, a vector controlled induction motor and centrifugal pump. The PV generator is forced to operate at its maximum power point by using an appropriate search algorithm integrated in the vector control. The optimization is realized without need to adding a DC-DC converter to the chain. The motor supply is also ensured in all insolation conditions. Simulation results show the effectiveness and feasibility of such an approach.

Photovoltaic energy potential of Quebec

International Nuclear Information System (INIS)

Royer, J.; Thomas, R.

1993-01-01

Results are presented from a study concerning the potential of photovoltaic (PV) energy in Quebec to the year 2010. The different PV applications which are or will be economically viable in Quebec for the study period are identified and evaluated in comparison with the conventional energy sources used for these applications. Two penetration scenarios are proposed. One considers little change at the level of policies established for commercialization of PV sources, and the other considers certain measures which accelerate the implementation of PV technology in certain niches. While the off-grid market is already motivated to adopt PV technology for economic reasons, it is forecast that all encouragement from lowering costs would accelerate PV sales, offering a larger purchasing power to all interested parties. Above all, lowered PV costs would open up the network market. Photovoltaics would have access to a much larger market, which will accelerate changes in the very nature of the industry and bring with it new reductions in the costs of producing PV systems. 5 refs., 1 fig., 7 tabs

Creating Public Awareness of Renewable Energy by Combining a Photovoltaic System and Nature

DEFF Research Database (Denmark)

Knott, Arnold; Lund, Dorthe Hedensted; Andersen, Thomas

2011-01-01

Energy is seemingly permanently and nearly everywhere in the western world available to the end consumer. While a majority of the western civilization is aware of the downsides of fossil energy sources and is favoring renewable energy sources, the energy consumption is still increasing. The situa......Energy is seemingly permanently and nearly everywhere in the western world available to the end consumer. While a majority of the western civilization is aware of the downsides of fossil energy sources and is favoring renewable energy sources, the energy consumption is still increasing....... The situation is quite clear to the experts in the field, but further awareness in the public must be created. Therefore this paper addresses a method of creating this awareness: installations that stimulate conversations of renewable energy. A solar tree was developed and built to serve young people with an AC....... The mechanical requirements and the developed solution is shown, before providing intensive insight into the electrical configuration, consisting of a battery, photovoltaic cells and a DC-AC converter. Furthermore a low complexity charge controller is presented. The resulting solar tree is capable of attracting...

Photovoltaics come to the rescue of energy savings

International Nuclear Information System (INIS)

Anon.

2006-01-01

In light of continuously rising energy prices and the necessity to step up environmental and climate protection measures, photovoltaics and solar thermal applications are being viewed with increased interest as alternative sources of energy. (authors)

Photovoltaic Power System with an Interleaving Boost Converter for Battery Charger Applications

Directory of Open Access Journals (Sweden)

Sheng-Yu Tseng

2012-01-01

Full Text Available This paper proposes a photovoltaic (PV power system for battery charger applications. The charger uses an interleaving boost converter with a single-capacitor turn-off snubber to reduce voltage stresses of active switches at turn-off transition. Therefore, active switches of the charger can be operated with zero-voltage transition (ZVT to decrease switching losses and increase conversion efficiency. In order to draw the maximum power from PV arrays and obtain the optimal power control of the battery charger, a perturbation-and-observation method and microchip are incorporated to implement maximum power point tracking (MPPT algorithm and power management. Finally, a prototype battery charger is built and implemented. Experimental results have verified the performance and feasibility of the proposed PV power system for battery charger applications.

Hybrid photovoltaic-diesel-battery systems for remote energy supply

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 and battery energy storage are powering isolated mountain lodges, information centres in nature parks, isolated farms or dwellings all over Europe. A total of 300000 buildings in Europe are estimated to be not connected to the public grid. This represents a major market potential for photovoltaics, 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 utilisation of the electric energy produced by the PV generator. (orig.) 8 refs.

Statistical thermodynamics foundation for photovoltaic and photothermal conversion. II. Application to photovoltaic conversion

Science.gov (United States)

Badescu, Viorel; Landsberg, Peter T.

1995-08-01

The general theory developed in part I was applied to build up two models of photovoltaic conversion. To this end two different systems were analyzed. The first system consists of the whole absorber (converter), for which the balance equations for energy and entropy are written and then used to derive an upper bound for solar energy conversion. The second system covers a part of the absorber (converter), namely the valence and conduction electronic bands. The balance of energy is used in this case to derive, under additional assumptions, another upper limit for the conversion efficiency. This second system deals with the real location where the power is generated. Both models take into consideration the radiation polarization and reflection, and the effects of concentration. The second model yields a more accurate upper bound for the conversion efficiency. A generalized solar cell equation is derived. It is proved that other previous theories are particular cases of the present more general formalism.

A high voltage gain quasi Z-source isolated DC/DC converter

DEFF Research Database (Denmark)

Siwakoti, Yam P.; Blaabjerg, Frede; Loh, Poh Chiang

2014-01-01

A compact quasi-Z-source DC/DC converter is presented with high voltage gain, isolated output, and improved efficiency. The improvements in size and performance were achieved by using a square wave inverter with only two output switches driving an isolating transformer in push-pull mode, followed...... by a voltage doubling output rectifier. The converter is well-suited to applications requiring a high voltage gain, especially renewable energy sources such as photovoltaic and fuel-cell power supplies. To demonstrate the converter's performance a prototype designed to output 400 V at 500 W was constructed...

Overview of Maximum Power Point Tracking Techniques for Photovoltaic Energy Production Systems

DEFF Research Database (Denmark)

Koutroulis, Eftichios; Blaabjerg, Frede

2015-01-01

A substantial growth of the installed photovoltaic systems capacity has occurred around the world during the last decade, thus enhancing the availability of electric energy in an environmentally friendly way. The maximum power point tracking technique enables maximization of the energy production...... of photovoltaic sources during stochastically varying solar irradiation and ambient temperature conditions. Thus, the overall efficiency of the photovoltaic energy production system is increased. Numerous techniques have been presented during the last decade for implementing the maximum power point tracking...... process in a photovoltaic system. This article provides an overview of the operating principles of these techniques, which are suited for either uniform or non-uniform solar irradiation conditions. The operational characteristics and implementation requirements of these maximum power point tracking...

13{sup th} Kassel symposium energy systems technology. Power converters in grids. Proceedings; 13. Kasseler Symposium Energie-Systemtechnik. Stromrichter in Netzen. Tagungsband

Energy Technology Data Exchange (ETDEWEB)

NONE

2008-07-01

Increasingly static converters are used for the integration of distributed power generators into the grid, e.g. photovoltaic systems and speed-variable wind energy converters. Also other power generators, storage systems and electrical loads are integrated via power electronics. A variety of product specific standards had been developed for integrating converters into the grid. These standards had emerged parallel to each other as a result of the demands of different forms of energy for the feed-in and consumption of electrical power. Meanwhile it became clear that applications which are sometimes very similar are determined differently by these standards. A further demand for harmonisation arises naturally in the international standardisation. In the run-up to the Symposium the second DERlab workshop 'European DERlab Workshop on Grid Inverters' will be held to prepare an international white book. The white book will be titled 'International White Book on Grid Inverters' and will describe medium to long-term tasks for the standardisation of grid-coupled converters. The 13th Kassel Symposium will give an overview of the wide range of applications of power electronic converters in the grid. Hereby similarities and differences should be disclosed, which will create a basis for further expert talks about the transition of our power supply to an increasing share of grid-coupled converters. Questions which will be discussed include: - What does a high share of converters mean for stability, safety and quality of the grid? - Is it necessary to adapt power system protection technology and safety regulations? - How shall converters act in the future, what is technically feasible, what is economically reasonable? - Are all converter-coupled systems able to provide ancillary services? - How will the grid codes change? Most of the presentations will be in German, simultaneous interpretation will be available. This book is prepared to give you a survey on

U.S. Department of Energy photovoltaic energy program contract summary, fiscal year 1999

Energy Technology Data Exchange (ETDEWEB)

Surek, T.; Hansen, A.

2000-02-17

This report summarizes the in-house and subcontracted research and development (R and D) activities under the National Center for Photovoltaics (NCPV) and US Department of Energy (DOE) National Photovoltaics Program from October 1, 1998, through September 30, 1999 (FY 1999). The mission of the DOE National Photovoltaics Program is to make PV a significant part of the domestic economy as an industry and an energy resource. The two primary goals of the national program are to (1) maintain the US industry's world leadership in research and technology development and (2) help the US industry remain a major, profitable force in the world market. The NCPV is part of the National PV Program and provides leadership and support to the national program toward achieving its mission and goals.

U.S. Department of Energy photovoltaic energy program contract summary, fiscal year 1999

International Nuclear Information System (INIS)

Surek, T.; Hansen, A.

2000-01-01

This report summarizes the in-house and subcontracted research and development (R and D) activities under the National Center for Photovoltaics (NCPV) and US Department of Energy (DOE) National Photovoltaics Program from October 1, 1998, through September 30, 1999 (FY 1999). The mission of the DOE National Photovoltaics Program is to make PV a significant part of the domestic economy as an industry and an energy resource. The two primary goals of the national program are to (1) maintain the US industry's world leadership in research and technology development and (2) help the US industry remain a major, profitable force in the world market. The NCPV is part of the National PV Program and provides leadership and support to the national program toward achieving its mission and goals

Linkages from DOE's Solar Photovoltaic R&D to Commercial Renewable Power from Solar Energy

Energy Technology Data Exchange (ETDEWEB)

Ruegg, Rosalie [TIA Consulting Inc., Emerald Isle, NC (United States); Thomas, Patrick [1790 Analytics LLC., Haddonfield, NJ (United States)

2011-04-01

DOE's Solar Photovoltaic R&D Subprogram promotes the development of cost-effective systems for directly converting solar energy into electricity for residential, commercial, and industrial applications. This study was commissioned to assess the extent to which the knowledge outputs of R&D funded by the DOE Solar PV subprogram are linked to downstream developments in commercial renewable power. A second purpose was to identify spillovers of the resulting knowledge to other areas of application. A third purpose was to lend support to a parallel benefit-cost study by contributing evidence of attribution of benefits to DOE.

Highly efficient maximum power point tracking using DC-DC coupled inductor single-ended primary inductance converter for photovoltaic power systems

Science.gov (United States)

Quamruzzaman, M.; Mohammad, Nur; Matin, M. A.; Alam, M. R.

2016-10-01

Solar photovoltaics (PVs) have nonlinear voltage-current characteristics, with a distinct maximum power point (MPP) depending on factors such as solar irradiance and operating temperature. To extract maximum power from the PV array at any environmental condition, DC-DC converters are usually used as MPP trackers. This paper presents the performance analysis of a coupled inductor single-ended primary inductance converter for maximum power point tracking (MPPT) in a PV system. A detailed model of the system has been designed and developed in MATLAB/Simulink. The performance evaluation has been conducted on the basis of stability, current ripple reduction and efficiency at different operating conditions. Simulation results show considerable ripple reduction in the input and output currents of the converter. Both the MPPT and converter efficiencies are significantly improved. The obtained simulation results validate the effectiveness and suitability of the converter model in MPPT and show reasonable agreement with the theoretical analysis.

EROI of crystalline silicon photovoltaics : Variations under different assumptions regarding manufacturing energy inputs and energy output

OpenAIRE

Lundin, Johan

2013-01-01

Installed photovoltaic nameplate power have been growing rapidly around the worldin the last few years. But how much energy is returned to society (i.e. net energy) by this technology, and which factors contribute the most to the amount of energy returned? The objective of this thesis was to examine the importance of certain inputs and outputs along the solar panel production chain and their effect on the energy return on (energy) investment (EROI) for crystalline wafer-based photovoltaics. A...

Study of Photovoltaic Energy Storage by Supercapacitors through Both Experimental and Modelling Approaches

Directory of Open Access Journals (Sweden)

Pierre-Olivier Logerais

2013-01-01

Full Text Available The storage of photovoltaic energy by supercapacitors is studied by using two approaches. An overview on the integration of supercapacitors in solar energy conversion systems is previously provided. First, a realized experimental setup of charge/discharge of supercapacitors fed by a photovoltaic array has been operated with fine data acquisition. The second approach consists in simulating photovoltaic energy storage by supercapacitors with a faithful and accessible model composed of solar irradiance evaluation, equivalent electrical circuit for photovoltaic conversion, and a multibranch circuit for supercapacitor. Both the experimental and calculated results are confronted, and an error of 1% on the stored energy is found with a correction largely within ±10% of the transmission line capacitance according to temperature.

Analysis of the economics of photovoltaic-diesel-battery energy systems for remote applications

Science.gov (United States)

Brainard, W. A.

1983-01-01

Computer simulations were conducted to analyze the performance and operating cost of a photovoltaic energy source combined with a diesel generator system and battery storage. The simulations were based on the load demand profiles used for the design of an all photovoltaic energy system installed in the remote Papago Indian Village of Schuchuli, Arizona. Twenty year simulations were run using solar insolation data from Phoenix SOLMET tapes. Total energy produced, energy consumed, operation and maintenance costs were calculated. The life cycle and levelized energy costs were determined for a variety of system configurations (i.e., varying amounts of photovoltaic array and battery storage).

Control Strategies for Trap Filter Interfaced Three-Phase Grid Connected Converters

DEFF Research Database (Denmark)

Min, Huang

In order to utilize renewable energy systems power electronics are needed to convert the energy to grid. The AC-DC and DC-AC power conversion are dominant in wind power system and photovoltaic system. However, the use of PWM scheme introduces undesirable harmonics. In order to enhance the grid...... damping in order to stabilize the whole system with resonance issue. LC trap filter application for current source converters to reduce the size of the filter and get a higher power factor....... integration of the renewable energy systems, the filter plays an important role. Even though this topic has already been widely studied, there are many optimizations and problems should be solved. How to design a filter for grid-connected converters in distributed generation system to get a lower loss...

Distributed Power System Virtual Inertia Implemented by Grid-Connected Power Converters

DEFF Research Database (Denmark)

Fang, Jingyang; Li, Hongchang; Tang, Yi

2018-01-01

Renewable energy sources (RESs), e.g. wind and solar photovoltaics, have been increasingly used to meet worldwide growing energy demands and reduce greenhouse gas emissions. However, RESs are normally coupled to the power grid through fast-response power converters without any inertia, leading...... to decreased power system inertia. As a result, the grid frequency may easily go beyond the acceptable range under severe frequency events, resulting in undesirable load-shedding, cascading failures, or even large-scale blackouts. To address the ever-decreasing inertia issue, this paper proposes the concept...... of distributed power system virtual inertia, which can be implemented by grid-connected power converters. Without modifications of system hardware, power system inertia can be emulated by the energy stored in the dc-link capacitors of grid-connected power converters. By regulating the dc-link voltages...

Photovoltaic solar energy;L'energie solaire photovoltaique

Energy Technology Data Exchange (ETDEWEB)

Mouratoglou, P. [EDF Energies Nouvelles, 75 - Paris (France); Therond, P.G. [EDF Dir. Nouvelles Technologies, 75 - Paris (France)

2009-11-15

The most important assets of photovoltaic energy for sustainable development are its simplicity (no need for complicated thermodynamical cycles) and the universal availability of the sun which explains its great popularity. The main restraint to its full development is the high cost of the technologies used. The silicon technology is the historical technology, it has high conversion rates but is expensive because of high fabrication costs. This technology represents 80% of the market. On the other hand the thin film technology with CdTe, CIS or CIGS is promising in terms of costs but requires research works to increase its conversion rate. Japan and Germany are the leader countries in terms of photovoltaic for research, industrial fabrication or state support, they are followed by Spain, Usa, and China. (A.C.)

Modelling of storage of the photovoltaic energy by super-capacitors

International Nuclear Information System (INIS)

Camara, Mohamed Ansoumane

2011-01-01

The storage by ultra-capacitors of photovoltaic energy is modeled in order to have an accurate and accessible model to integrate ultra-capacitors into solar energy conversion systems. Ultra-capacitors are modeled by a multi-branch circuit representation composed of resistors and capacitors with variable voltage whose values are determined by an accurate characterization experiment. Moreover, all the elements of a typical photovoltaic energy conversion system are modeled by using the Matlab/Simulink software (solar radiation, photovoltaic arrays, regulator, batteries and charges). The energy storage model by ultra-capacitors is then validated by the good agreement of measured values taken in real conditions with the results provided by simulations. Finally, two examples are proposed and discussed: the determination of the storage duration of ultra-capacitors versus solar irradiance and ambient temperature, and the integration of ultra-capacitors in the electrical feeding system of a DC motor to reduce the electrical current peak of the battery at the start of the motor. (author) [fr

Electric properties of organic and mineral electronic components, design and modelling of a photovoltaic chain for a better exploitation of the solar energy

International Nuclear Information System (INIS)

Aziz, A.

2006-11-01

The research carried out in this thesis relates to the mineral, organic electronic components and the photovoltaic systems. Concerning the mineral semiconductors, we modelled the conduction properties of the structures metal/oxide/semiconductor (MOS) strongly integrated in absence and in the presence of charges. We proposed a methodology allowing characterizing the ageing of structures MOS under injection of the Fowler Nordheim (FN) current type. Then, we studied the Schottky diodes in polymers of type metal/polymer/metal. We concluded that: The mechanism of the charges transfer, through the interface metal/polymer, is allotted to the thermo-ionic effect and could be affected by the lowering of the potential barrier to the interface metal/polymer. In the area of photovoltaic energy, we conceived and modelled a photovoltaic system of average power (100 W). We showed that the adaptation of the generator to the load allows a better exploitation of solar energy. This is carried out by the means of the converters controlled by an of type MPPT control provided with a detection circuit of dysfunction and restarting of the system. (author)

Fabrication and performance analysis of concentrated hybrid photovoltaic system

Directory of Open Access Journals (Sweden)

Murthy Krishna

2018-01-01

Full Text Available Sun is the most important source of renewable source of energy. During the past few decades there has been an ever-increasing interest in Photovoltaic (PV cells as it directly converts solar radiation into electricity. This paper involves the performance study of photovoltaic system under concentrated solar radiation. The main problem with the concentration solar energy is the drastic increase in temperature of the photovoltaic module resulting in a decrease in performance efficiency of the system. This problem of overheating of the system can be overcome by providing cooling which would ensure operation of the module in the optimal temperature range. Hence, the setup would function as a hybrid model serving the dual purpose of power generation while also utilizing the waste heat for water heating applications. The experimental set up consist of a novel arrangement of concentrator and reflector and the cooling system. The Hybrid Photovoltaic System was repeatedly tested under real time conditions on several days. A comparison was drawn between the results obtained from direct exposure of a standard photovoltaic module to that obtained from the hybrid system in order to better understand the improvement in performance parameters. The study shown a significant improvement of output of standard photovoltaic module under the concentrated solar radiation.

Applied photovoltaics as a practical education in renewable energy technologies

International Nuclear Information System (INIS)

Stoev, Mitko

2009-01-01

The optional course „Applied Photovoltaic” for MEng students specializing in Electronics at the Faculty of Electronics and Automation, TU-Plovdiv is presented. The main topics of the advanced PV course as a modern sustainable energetic based on the photovoltaic effect and energy from Sun as a renewable energy source; materials and technologies in photovoltaic; design of solar cells and PV modules and PV generators up to 100 kWp; BIPV and CIPV systems; hybrid PV systems; PV mounting; monitoring of PV systems and EC regulations for PV systems connected to the utility grid are discussed. The advanced teaching method by online e-platform with virtual resources is presented. Key words: PV education, PV technologies, applied photovoltaic, e-platform

ENERGY MANAGEMENT OF PHOTOVOLTAIC SYSTEMS USING FUEL CELLS

Directory of Open Access Journals (Sweden)

Cristian MIRON

2016-11-01

Full Text Available Renewable energy generators show an accelerated growth both in terms of production wise, as well as in research fields. Focusing only on photovoltaic panels, the generated energy has the disadvantage of being strongly oscillatory in evolution. The classical solution is to create a network between photovoltaic farms spanning on large distances, in order to share the total energy before sending it to the clients. A solution that was recently proposed is going to use hydrogen in order to store the energy surplus. Fuel Cells (FCs represent energy generators whose energy vector is usually hydrogen. These have already started the transition from the laboratory context towards commercialization. Due to their high energy density, as well as their theoretical infinite storage capacity through hydrogen, configurations based on electrolyzers and FCs are seen as high potential storage systems, both for vehicle and for stationary applications. Therefore, a study on such distributed control systems is of high importance. This paper analyses the existing solutions, with emphasis on a particular case where a supervisory system is developed and tested in a specialised simulation software.

A New Modular Multilevel Converter with Integrated Energy Storage

DEFF Research Database (Denmark)

Trintis, Ionut; Munk-Nielsen, Stig; Teodorescu, Remus

2011-01-01

applications. Furthermore, this solution can interconnect a DC and AC grid with bidirectional power flow, where both of them can receive or generate excess power to the third source integrated in each converter sub-module. This particularity enables the converter usage as a high voltage UPS system......This paper introduces a new modular converter with integrated energy storage based on the cascaded half-bridge modular multilevel converter with common DC bus. It represents a complete modular solution with power electronics and energy storage building blocks, for medium and high voltage...... in the future HVDC meshed grids. Its functionality and flexibility makes the converter independent on the energy storage unit characteristic. The converter concept with its basic functions and control schemes are described and evaluated in this paper....

High Efficiency Non-isolated Three Port DC-DC Converter for PV-Battery Systems

DEFF Research Database (Denmark)

Tomas Manez, Kevin; Anthon, Alexander; Zhang, Zhe

2016-01-01

This paper presents a nonisolated Three Port Converter (TPC) with a unidirectional port for photovoltaic (PV) panels and a bidirectional port for energy storage. With the proposed topology single power conversion is performed between each port, so high efficiencies are obtained. A theoretical...

Grid-Connected Photovoltaic System with Active Power Filtering Functionality

Directory of Open Access Journals (Sweden)

Joaquín Vaquero

2018-01-01

Full Text Available Solar panels are an attractive and growing source of renewable energy in commercial and residential applications. Its use connected to the grid by means of a power converter results in a grid-connected photovoltaic system. In order to optimize this system, it is interesting to integrate several functionalities into the power converter, such as active power filtering and power factor correction. Nonlinear loads connected to the grid generate current harmonics, which deteriorates the mains power quality. Active power filters can compensate these current harmonics. A photovoltaic system with added harmonic compensation and power factor correction capabilities is proposed in this paper. A sliding mode controller is employed to control the power converter, implemented on the CompactRIO digital platform from National Instruments Corporation, allowing user friendly operation and easy tuning. The power system consists of two stages, a DC/DC boost converter and a single-phase inverter, and it is able to inject active power into the grid while compensating the current harmonics generated by nonlinear loads at the point of common coupling. The operation, design, simulation, and experimental results for the proposed system are discussed.

Organic photovoltaic energy in Japan

International Nuclear Information System (INIS)

2007-01-01

Japan finances research programs on photovoltaic conversion since 1974. Research in this domain is one of the 11 priorities of NEDO, the agency of means of the ministry of economy, trade and industry of Japan. The search for an abatement of production costs and of an increase of cells efficiency is mentioned in NEDO's programs as soon as the beginning of the 1990's. A road map has been defined which foresees photovoltaic energy production costs equivalent to the ones of thermal conversion by 2030, i.e. 7 yen/kWh (4.4 cents of euro/kWh). The use of new materials in dye-sensitized solar cells (DSSC) or organic solar cells, and of new structures (multi-junctions) is explored to reach this objective. The organic photovoltaic technology is more particularly considered for small generation units in mobile or domestic technologies. Japan is particularly in advance in the improvement of DSSC cells efficiency, in particular in the domain of the research on solid electrolytes. Europe seems more in advance in the domain of the new generation of organic solar cells. Therefore, a complementarity may be found between Japan and French teams in the domain of organic solar cells improvement through collaboration programs. (J.S.)

The active control strategy on the output power for photovoltaic-storage systems based on extended PQ-QV-PV Node

Science.gov (United States)

Xu, Chen; Zhou, Bao-Rong; Zhai, Jian-Wei; Zhang, Yong-Jun; Yi, Ying-Qi

2017-05-01

In order to solve the problem of voltage exceeding specified limits and improve the penetration of photovoltaic in distribution network, we can make full use of the active power regulation ability of energy storage(ES) and the reactive power regulation ability of grid-connected photovoltaic inverter to provide support of active power and reactive power for distribution network. A strategy of actively controlling the output power for photovoltaic-storage system based on extended PQ-QV-PV node by analyzing the voltage regulating mechanism of point of commom coupling(PCC) of photovoltaic with energy storage(PVES) by controlling photovoltaic inverter and energy storage. The strategy set a small wave range of voltage to every photovoltaic by making the type of PCC convert among PQ, PV and QV. The simulation results indicate that the active control method can provide a better solution to the problem of voltage exceeding specified limits when photovoltaic is connectted to electric distribution network.

Application of Circuit Model for Photovoltaic Energy Conversion System

Directory of Open Access Journals (Sweden)

Natarajan Pandiarajan

2012-01-01

Full Text Available Circuit model of photovoltaic (PV module is presented in this paper that can be used as a common platform by material scientists and power electronic circuit designers to develop better PV power plant. Detailed modeling procedure for the circuit model with numerical dimensions is presented using power system blockset of MATLAB/Simulink. The developed model is integrated with DC-DC boost converter with closed-loop control of maximum power point tracking (MPPT algorithm. Simulation results are validated with the experimental setup.

Photovoltaic power - An important new energy option

Science.gov (United States)

Ferber, R. R.

1983-01-01

A review of photovoltaic (PV) power technology is presented with an emphasis of PV as an economical and technically feasible alternative source of energy. The successful completion of the development and transfer of emerging low-cost technologies into a fully commercialized status are identified as the means to the realization of this option's full potential. The DOE National Photovoltaics Program, a significant sponsor of PV R&D, expects both flat-plate and concentrator collectors to meet established cost targets. Citing the DOE large flat-plate grid-connected system project of the Sacramento Municipal Utility District, current technology modules priced at near $5/Wp (1983 dollars) are steadily reducing costs. A recent DOE study suggests that PV-generated electricity produced at a 30-year levelized cost of 15 cents per kWh would represent a viable energy supply alternative for the nation.

Devices and optics for photovoltaic conversion

International Nuclear Information System (INIS)

Arujo, G.L.

1991-01-01

Photovoltaic energy is one of the most promising renewable energies. The contents of this article deals firstly with the physics of the devices and the optics employed to convert directly sunlight into electricity. Secondly the state of the art of the high efficiency solar cells and concentration systems will be addressed. Finally, there will be some concluding comments about the future prospects of the photovoltaic energy. PV energy conversion is at present a viable technology to produce electricity. But unfortunately its cost is still too high to be competitive with grid connected applications. Roughly speaking there are two main strategies for reducing costs in PV: One of them relies on thin-film, low cost solar cells and modules and the other relies on high efficiency solar cells and modules used, in many cases, in combination with optical concentration. This work will focus in high efficiency solar cells, what means that good quality crystalline semiconductor materials are involved, and in the optics used in concentration systems. 25 figs, 2 tabs

The effect of seasonal variation on the performances of grid connected photovoltaic system in southern of Algeria

Science.gov (United States)

Zaghba, L.; Khennane, M.; Terki, N.; Borni, A.; Bouchakour, A.; Fezzani, A.; Mahamed, I. Hadj; Oudjana, S. H.

2017-02-01

This paper presents modeling, simulation, and analysis evaluation of the grid-connected PV generation system performance under MATLAB/Simulink. The objective is to study the effect of seasonal variation on the performances of grid connected photovoltaic system in southern of Algeria. This system works with a power converter. This converter allows the connection to the network and extracts maximum power from photovoltaic panels with the MPPT algorithm based on robust neuro-fuzzy sliding approach. The photovoltaic energy produced by the PV generator will be completely injected on the network. Simulation results show that the system controlled by the neuro-fuzzy sliding adapts to changing external disturbances and show their effectiveness not only for continued maximum power point but also for response time and stability.

Optimal Operation of Photovoltaic System with a DC-DC Boost Converter FED SAF Using ICosφ Algorithm

Directory of Open Access Journals (Sweden)

G.Vijayakumar

2014-07-01

Full Text Available This paper presents an optimal utilization of Photovoltaic (PV solar system based Shunt Active Filter (PV-SAF for harmonic mitigation, real and reactive power compensation at the point of common coupling (PCC throughout the day. This PV system operated SAF reduces the energy consumption by disconnecting the utility grid from the load through semiconductor switches, when the PV system generates excessive or equal real power to the required load demand. However, the reduction of energy consumption is always desirable for the reduction of panel tariff and global warming gasses. The PV module is connected to the DC side of SAF through the DC-DC converter with fuzzy based Perturb & Observe (P&O Maximum Power Point Tracking (MPPT algorithm to eliminate the drawback of the conventional PV system by tracking maximum power point of the PV array is presented. The reference currents extract by the Fuzzy logic controller based ICosΦ control strategy. This proposed PV-SAF, if connected at the terminals of a small industry or a home or a small enlightening institution can avoid interruptible power supply, use of individual stabilizer and potential panel tariff over a 12 hour period. A MATLAB simulink is presented to validate the advantage of the proposed system.

Power converter for raindrop energy harvesting application: Half-wave rectifier

Science.gov (United States)

Izrin, Izhab Muhammad; Dahari, Zuraini

2017-10-01

Harvesting raindrop energy by capturing vibration from impact of raindrop have been explored extensively. Basically, raindrop energy is generated by converting the kinetic energy of raindrop into electrical energy by using polyvinylidene fluoride (PVDF) piezoelectric. In this paper, a power converter using half-wave rectifier for raindrop harvesting energy application is designed and proposed to convert damping alternating current (AC) generated by PVDF into direct current (DC). This research presents parameter analysis of raindrop simulation used in the experiment and resistive load effect on half-wave rectifier converter. The experiment is conducted by using artificial raindrop from the height of 1.3 m to simulate the effect of different resistive load on the output of half-wave rectifier converter. The results of the 0.68 MΩ resistive load showed the best performance of the half-wave rectifier converter used in raindrop harvesting energy system, which generated 3.18 Vaverage. The peak instantaneous output generated from this experiment is 15.36 µW.

Experimental Learning of Digital Power Controller for Photovoltaic Module Using Proteus VSM

Directory of Open Access Journals (Sweden)

Abhijit V. Padgavhankar

2014-01-01

Full Text Available The electric power supplied by photovoltaic module depends on light intensity and temperature. It is necessary to control the operating point to draw the maximum power of photovoltaic module. This paper presents the design and implementation of digital power converters using Proteus software. Its aim is to enhance student’s learning for virtual system modeling and to simulate in software for PIC microcontroller along with the hardware design. The buck and boost converters are designed to interface with the renewable energy source that is PV module. PIC microcontroller is used as a digital controller, which senses the PV electric signal for maximum power using sensors and output voltage of the dc-dc converter and according to that switching pulse is generated for the switching of MOSFET. The implementation of proposed system is based on learning platform of Proteus virtual system modeling (VSM and the experimental results are presented.

Photovoltaic power systems energy storage

International Nuclear Information System (INIS)

Buldini, P.L.

1991-01-01

Basically, the solar photovoltaic power system consists of: Array of solar panels; Charge/voltage stabilizer; Blocking diode and Storage device. The storage device is a very important part of the system due to the necessity to harmonize the inevitable time shift between energy supply and demand. As energy storage, different devices can be utilized, such as hydropumping, air or other gas compression, flywheel, superconducting magnet, hydrogen generation and so on, but actually secondary (rechargeable) electrochemical cells appear to be the best storage device, due to the direct use for recharge of the d.c. current provided by the solar panels, without any intermediate step of energy transformation and its consequent loss of efficiency

Study and simulation of a MPPT controller based on fuzzy logic controller for photovoltaic system

Energy Technology Data Exchange (ETDEWEB)

Belaidi, R.; Chikouche, A.; Fathi, M.; Mohand Kaci, G.; Smara, Z. [Unite de Developpement des Equipements Solaires (Algeria); Haddouche, A. [Universite Badji Mokhtar (Algeria)], E-mail: rachidi3434@yahoo.fr

2011-07-01

With the depletion of fossil fuels and the increasing concerns about the environment, renewable energies have become more and more attractive. Photovoltaic systems convert solar energy into electric energy through the use of photovoltaic cells. The aim of this paper is to compare the capacity of fuzzy logic and perturb and observe controllers in optimizing the control performance of photovoltaic systems. Simulations were performed using Matlab and Simulink and were analyzed to determine the effectiveness of both controllers and compare them. Results showed that the fuzzy controller has a better dynamic performance than the perturb and observe controller in terms of response time and damping characteristics. In addition, the fuzzy controller was found to better follow the maximum power point and to provide faster convergence and lower statistical error. This study demonstrated that the fuzzy controller gives a better performance than traditional controllers in optimizing the performance of photovoltaic systems.

Solar electric power generation photovoltaic energy systems

CERN Document Server

Krauter, Stefan CW

2007-01-01

Solar electricity is a viable, environmentally sustainable alternative to the world's energy supplies. In support, this work examines the various technical parameters of photovoltaic systems. It analyzes the study of performance and yield (including optical, thermal, and electrical parameters and interfaces).

EXAMINING A SERIES RESONANT INVERTER CIRCUIT TO USE IN THE PHOTOVOLTAIC ENERGY CONVERSION SYSTEMS

Directory of Open Access Journals (Sweden)

Engin ÇETİN

2004-03-01

Full Text Available As we know, solar energy is the energy source which is environment friendly, renewable, and can be found easily. Particularly, in the recent years, interest on producing electrical energy by alternative energy sources increased because of the fact that underground sources are not enough to produce energy in the future and also these sources cause enviromental pollution. The solar energy is one of the most popular one among the alternative energy sources. Photovoltaic systems produce the electrical energy from the sunlight. In this study, a series resonant inverter circuit which is used in the photovoltaic energy conversion systems has been examined.Effects of the series resonant inverter circuit on the photovoltaic energy conversion system have been investigated and examined

Design and Control of an Inverter for Photovoltaic Applications

OpenAIRE

Kjær, Søren Bækhøj

2005-01-01

The energy demand in the world is steadily increasing and new types of energy sources must be found in order to cover the future demands, since the conventional sources are about to be emptied. One type of renewable energy source is the photovoltaic (PV) cell, which converts sunlight to electrical current, without any form for mechanical or thermal interlink. PV cells are usually connected together to make PV modules, consisting of 72 PV cells, which generates a DC voltage between 23 Volt to ...

Temperature and Solar Radiation Effects on Photovoltaic Panel Power

OpenAIRE

Karafil, Akif; Ozbay, Harun; Kesler, Metin

2016-01-01

Solar energy is converted to electrical energy directly by semi-conductors materials used in Photovoltaic (PV) panels. Although, there has been great advancements in semi-conductor material technology in recent years panel efficiency is very lower. There are many factors affecting the panel efficiency such as tilt angle, shading, dust, solar radiation level, temperature and wiring losses. Among these factors, solar radiation level and temperature are more prominent. The solar radiation level ...

Experimental Performance Investigation of Photovoltaic/Thermal (PV–T System

Directory of Open Access Journals (Sweden)

Bakir C.

2013-04-01

Full Text Available Photovoltaic solar cells convert light energy from the sun into electricity. Photovoltaic cells are produced by semi-conducting materials to convert the energy into electricity and during this process heat is absorbed by the solar radiation. This heat causes a loss of electricity generation efficiencies.In this study, an experimental setup was designed and established to test two separate photovoltaic panel systems with alone PV and with water cooling system PV/T to examine the heat effect on PV systems. The absorbed heat energy behind the photovoltaic cell's surface in insulated ambient was removed by means of a water cooling system and the tests for both systems were simultaneously performed along the July 2011. It is found that without active water cooling, the temperature of the PV module was higher during day time and solar cells could only achieve around 8% conversion efficiency. On the other hand, when the PV module was operated with active water cooling condition, the temperature dropped significantly, leading to an increase in the efficiency of solarcells as much as 13.6%. Gained from absorbed solar heat and maximum thermal conversion efficiencies of the system are determined as 49% and 51% for two different mass flow rates. It is observed that water flow rate is effective on the increasing the conversion efficiency as well as absorption and transitionrates of cover glass in PV/T (PV–Thermal collector, the insulation material and cell efficiency. As a conclusion, the conversion efficiency of the PV system with water cooling might be improved on average about 10%. Therefore, it is recommended that PV system should be designed with most efficient type cooling system to enhance the efficiency and to decrease the payback period.

Model Predictive Control techniques with application to photovoltaic, DC Microgrid, and a multi-sourced hybrid energy system

Science.gov (United States)

Shadmand, Mohammad Bagher

Renewable energy sources continue to gain popularity. However, two major limitations exist that prevent widespread adoption: availability and variability of the electricity generated and the cost of the equipment. The focus of this dissertation is Model Predictive Control (MPC) for optimal sized photovoltaic (PV), DC Microgrid, and multi-sourced hybrid energy systems. The main considered applications are: maximum power point tracking (MPPT) by MPC, droop predictive control of DC microgrid, MPC of grid-interaction inverter, MPC of a capacitor-less VAR compensator based on matrix converter (MC). This dissertation firstly investigates a multi-objective optimization technique for a hybrid distribution system. The variability of a high-penetration PV scenario is also studied when incorporated into the microgrid concept. Emerging (PV) technologies have enabled the creation of contoured and conformal PV surfaces; the effect of using non-planar PV modules on variability is also analyzed. The proposed predictive control to achieve maximum power point for isolated and grid-tied PV systems speeds up the control loop since it predicts error before the switching signal is applied to the converter. The low conversion efficiency of PV cells means we want to ensure always operating at maximum possible power point to make the system economical. Thus the proposed MPPT technique can capture more energy compared to the conventional MPPT techniques from same amount of installed solar panel. Because of the MPPT requirement, the output voltage of the converter may vary. Therefore a droop control is needed to feed multiple arrays of photovoltaic systems to a DC bus in microgrid community. Development of a droop control technique by means of predictive control is another application of this dissertation. Reactive power, denoted as Volt Ampere Reactive (VAR), has several undesirable consequences on AC power system network such as reduction in power transfer capability and increase in

Effect of pole zero location on system dynamics of boost converter for micro grid

Science.gov (United States)

Lavanya, A.; Vijayakumar, K.; Navamani, J. D.; Jayaseelan, N.

2018-04-01

Green clean energy like photo voltaic, wind energy, fuel cell can be brought together by microgrid.For low voltage sources like photovoltaic cell boost converter is very much essential. This paper explores the dynamic analysis of boost converter in a continuous conduction mode (CCM). The transient performance and stability analysis is carried out in this paper using time domain analysis and frequency domain analysis techniques. Boost converter is simulated using both PSIM and MATLAB software. Furthermore, state space model obtained and the transfer function is derived. The converter behaviour when a step input is applied is analyzed and stability of the converter is analyzed from bode plot frequency for open loop. Effect of the locations of poles and zeros in the transfer function of boost converter and how the performance parameters are affected is discussed in this paper. Closed loop performance with PI controller is also analyzed for boost converter.

Technical Study of a Standalone Photovoltaic-Wind Energy Based Hybrid Power Supply Systems for Island Electrification in Malaysia.

Science.gov (United States)

Samrat, Nahidul Hoque; Ahmad, Norhafizan; Choudhury, Imtiaz Ahmed; Taha, Zahari

2015-01-01

Energy is one of the most important factors in the socioeconomic development of a country. In a developing country like Malaysia, the development of islands is mostly related to the availability of electric power. Power generated by renewable energy sources has recently become one of the most promising solutions for the electrification of islands and remote rural areas. But high dependency on weather conditions and the unpredictable nature of these renewable energy sources are the main drawbacks. To overcome this weakness, different green energy sources and power electronic converters need to be integrated with each other. This study presents a battery storage hybrid standalone photovoltaic-wind energy power supply system. In the proposed standalone hybrid system, a DC-DC buck-boost bidirectional converter controller is used to accumulates the surplus hybrid power in the battery bank and supplies this power to the load during the hybrid power shortage by maintaining the constant dc-link voltage. A three-phase voltage source inverter complex vector control scheme is used to control the load side voltage in terms of the voltage amplitude and frequency. Based on the simulation results obtained from MATLAB/Simulink, it has been found that the overall hybrid framework is capable of working under variable weather and load conditions.

Technical Study of a Standalone Photovoltaic-Wind Energy Based Hybrid Power Supply Systems for Island Electrification in Malaysia.

Directory of Open Access Journals (Sweden)

Nahidul Hoque Samrat

Full Text Available Energy is one of the most important factors in the socioeconomic development of a country. In a developing country like Malaysia, the development of islands is mostly related to the availability of electric power. Power generated by renewable energy sources has recently become one of the most promising solutions for the electrification of islands and remote rural areas. But high dependency on weather conditions and the unpredictable nature of these renewable energy sources are the main drawbacks. To overcome this weakness, different green energy sources and power electronic converters need to be integrated with each other. This study presents a battery storage hybrid standalone photovoltaic-wind energy power supply system. In the proposed standalone hybrid system, a DC-DC buck-boost bidirectional converter controller is used to accumulates the surplus hybrid power in the battery bank and supplies this power to the load during the hybrid power shortage by maintaining the constant dc-link voltage. A three-phase voltage source inverter complex vector control scheme is used to control the load side voltage in terms of the voltage amplitude and frequency. Based on the simulation results obtained from MATLAB/Simulink, it has been found that the overall hybrid framework is capable of working under variable weather and load conditions.

Coordinated Control of Wave Energy Converters Subject to Motion Constraints

Directory of Open Access Journals (Sweden)

Liguo Wang

2016-06-01

Full Text Available In this paper, a generic coordinated control method for wave energy converters is proposed, and the constraints on motion amplitudes and the hydrodynamic interaction between converters are considered. The objective of the control problem is to maximize the energy converted from ocean waves, and this is achieved by coordinating the power take-off (PTO damping of each wave energy converter in the frequency domain in each sea state. In a case study, a wave energy farm consisting of four converters based on the concept developed by Uppsala University is studied. In the solution, motion constraints, including constraints on the amplitudes of displacement and velocity, are included. Twelve months of sea states, based on measured wave data at the Lysekil test site on the Swedish west coast, are used in the simulation to evaluate the performance of the wave energy farm using the new method. Results from the new coordinated control method and traditional control method are compared, indicating that the coordinated control of wave energy converters is an effective way to improve the energy production of wave energy farm in harmonic waves.

Modular assembly of a photovoltaic solar energy receiver

Science.gov (United States)

Graven, Robert M.; Gorski, Anthony J.; Schertz, William W.; Graae, Johan E. A.

1978-01-01

There is provided a modular assembly of a solar energy concentrator having a photovoltaic energy receiver with passive cooling. Solar cell means are fixedly coupled to a radiant energy concentrator. Tension means bias a large area heat sink against the cell thereby allowing the cell to expand or contract with respect to the heat sink due to differential heat expansion.

Solar energy converter using surface plasma waves

Science.gov (United States)

Anderson, L. M. (Inventor)

1984-01-01

Sunlight is dispersed over a diffraction grating formed on the surface of a conducting film on a substrate. The angular dispersion controls the effective grating period so that a matching spectrum of surface plasmons is excited for parallel processing on the conducting film. The resulting surface plasmons carry energy to an array of inelastic tunnel diodes. This solar energy converter does not require different materials for each frequency band, and sunlight is directly converted to electricity in an efficient manner by extracting more energy from the more energetic photons.

Biomass converted carbon quantum dots for all-weather solar cells

International Nuclear Information System (INIS)

Meng, Yuanyuan; Zhang, Yue; Sun, Weiyin; Wang, Min; He, Benlin; Chen, Haiyan; Tang, Qunwei

2017-01-01

Highlights: •CQDs are converted from soybean powders by a hydrothermal method. •The biomass converted CQDs are used for all-weather DSSCs. •The so-called all-weather DSSCs can generate electricity in the daytime and dark. •A dark efficiency as high as 7.97% is determined on the all-weather photovoltaics. •The launched solar cell extend our knowledge of advanced all-weather solar cells. -- Abstract: A great challenge for state-of-the-art photovoltaic devices is to realize electric power generation in all weathers. We constructively demonstrate here the conversion from biomass to carbon quantum dots for all-weather carbon quantum dot solar cells that can generate electricity in the daytime and in the dark. The combination of green-emitting long persistence phosphors with mesoscopic titanium dioxide realizes optical storage by composite photoanode under illumination and excitation to monochromatic green light in the dark. The optimized all-weather solar cell yields maximized dark power conversion efficiency as high as 7.97% along with persistent electricity output for several hours. This work begins a photovoltaic revolution to forward all-weather solar cells as future energy solutions.

Energy savings assessment for digital-to-analog converter boxes

International Nuclear Information System (INIS)

Cheung, Hoi Ying; Meier, Alan; Brown, Richard

2011-01-01

The Digital Television (DTV) Converter Box Coupon Program was administered by the U.S. government to subsidize purchases of digital-to-analog converter boxes, with up to two $40 coupons for each eligible household. In order to qualify as Coupon Eligible Converter Boxes (CECBs), these devices had to meet a number of minimum performance specifications, including energy efficiency standards. The Energy Star Program also established voluntary energy efficiency specifications that are more stringent than the CECB requirements. In this study, we measured the power and energy consumptions for a sample of 12 CECBs (including 6 Energy Star labeled models) in-use in homes and estimated aggregate energy savings produced by the energy efficiency policies. Based on the 35 million coupons redeemed through the end of the program, our analysis indicates that between 2500 and 3700 GWh per year are saved as a result of the energy efficiency policies implemented on digital-to-analog converter boxes. The energy savings generated are equivalent to the annual electricity use of 280,000 average US homes. - Research highlights: → We examined energy efficiency policies on digital-to-analog converter boxes in US. → The government assistance program resulted in high participation. → 35 million coupons were redeemed for the purchases of energy efficient DTAs. → Between 2500 and 3700 GWh per year are saved as a result of the policies. → Savings are equivalent to the annual electricity use of 280,000 average US homes.

Advances in spectral conversion for photovoltaics: up-converting Er3+ doped YF3 nano-crystals in transparent glass ceramic

Science.gov (United States)

Marques-Hueso, Jose; Chen, Daqin; MacDougall, Sean K. W.; Wang, Yuansheng; Richards, Bryce S.

2011-09-01

Up- and down-conversion (UC, DC) constitute two singular routes to achieve improved energy harvesting of sunlight by changing its shape of the solar spectrum. To obtain a significant conversion rate two main challenges have to be overcome: i) the excited lanthanide ions have to emit efficiently, a target which has been better accomplished for DC materials; ii) the absorption in the lanthanide-based UC and DC layers has to be high to ensure a sizeable fraction of photons can be harvested. In this paper, we review such materials and their use as spectral converters for photovoltaics (PV), paying special attention to the UC and DC processes in lanthanide glasses in fluoride matrices. We discuss the challenges that need to be overcome in order to implement these materials in real PV devices. Finally, we will present the synthesis of erbium (Er3+) doped YF3 nano-crystals embedded in transparent glass ceramic (TGC) by melt quenching. This material presents a low phonon energy environment for the Er3+ ions due to the fluoride crystals, while the silica glass provides chemical and mechanical stability to the compound.

Review of photovoltaic energy development in Kenya for rural electrification

International Nuclear Information System (INIS)

Rabah, K.V.O.; Ndjeli, L.; Raturi, A.K.

1995-10-01

Energy demand is rapidly growing throughout much of the developing world, where an estimated two billion people, mostly from sparsely populated areas, currently live without electricity. As electrical energy systems are selected to help meet these people's electricity need, the environmental ramifications of the generating systems become increasingly important. Photovoltaic systems generate electricity without emitting greenhouse gases, and result in global, regional and local air quality advantages. In this work we intend to carry out research and development of photovoltaic solar cells for rural electrification - especially solar powered water pumping. (author). 56 refs, 11 figs

Final report for Assembling Microorganisms into Energy Converting Materials

Energy Technology Data Exchange (ETDEWEB)

Sahin, Ozgur

2018-03-26

The goal of this project was to integrate microorganisms capable of reversible energy transduction in response to changing relative humidity with non-biological materials to create hybrid energy conversion systems. While plants and many other biological organisms have developed structures that are extraordinarily effective in converting changes in relative humidity into mechanical energy, engineered energy transduction systems rarely take advantage of this powerful phenomenon. Rather than developing synthetic materials that can convert changes in relative humidity in to mechanical energy, we developed approaches to assemble bacterial spores into larger materials. These materials can convert energy from evaporation of water in dry atmospheric conditions, which we demonstrated by building energy harvesters from these materials. We have also developed experiments to investigate the interaction of water with the spore material, and to determine how this interaction imposes limits on energy conversion. In addition, we carried out theoretical calculations to investigate the limits imposed by the environmental conditions to the power available in the energy harvesting process. These calculations took into account heat and water vapor transfer in the atmosphere surrounding the spore based materials. Overall, our results suggest that biomolecular materials are promising candidates to convert energy from evaporation.

Superconducting energy stabilizer with charging and discharging DC-DC converters

International Nuclear Information System (INIS)

Kim, S.H.; Kostecki, E.L.; DeWinkel, C.C.

1992-01-01

This patent describes a superconducting energy stabilizer having multiple load connections and employing DC-DC conversion for storing energy in a superconducting inductive energy storage device having a first end and a second end, and for releasing the stored energy from the superconducting inductive energy storage device to a load or loads or to a utility or an industrial electrical distribution system, the superconducting energy stabilizer having multiple load connections and employing DC-DC conversion. It comprises: energy storage cell means for supplying energy to the load, discharging DC-DC converter means for releasing energy from the superconducting inductive energy storage device to the energy storage cell means, the discharging DC-DC converter means having input terminals, output terminals, and a discharging control line means for carrying signals controlling the operation of the discharging DC-DC converter means, one of the input terminals of the discharging DC-DC converter means coupled to the first end of the superconducting energy storage device

Photovoltaic energy systems: Program summary fiscal year 1983

Science.gov (United States)

1984-01-01

An overview of government funded activities in photovoltaic energy conversion research is given. Introductory information, a list of directing organizations, a list of acronyms and abbreviations, and an index of current contractors are given.

Towards a more efficient energy use in photovoltaic powered products

NARCIS (Netherlands)

Kan, S.Y.; Strijk, R.

2006-01-01

This paper analyzes the energy saving and power management solutions necessary to improve the energy consumption efficiency in photovoltaic powered products. Important in the design of such products is not only the energy supply optimization required to deliver the actual energy to fulfil their

The heat recovery with heat transfer methods from solar photovoltaic systems

International Nuclear Information System (INIS)

Özakın, A. N.; Karsli, S.; Kaya, F.; Güllüce, H.

2016-01-01

Although there are many fluctuations in energy prices, they seems like rising day by day. Thus energy recovery systems have increasingly trend. Photovoltaic systems converts solar radiation directly into electrical energy thanks to semiconductors. But due to the nature of semiconductors, whole of solar energy cannot turn into electrical energy and the remaining energy turns into waste heat. The aim of this research is evaluate this waste heat energy by air cooling system. So, the energy efficiency of the system will be increased using appropriate heat transfer technologies such as fin, turbulator etc. (paper)

Microinverters for employment in connection with photovoltaic modules

Science.gov (United States)

Lentine, Anthony L.; Nielson, Gregory N.; Okandan, Murat; Johnson, Brian Benjamin; Krein, Philip T.

2015-09-22

Microinverters useable in association with photovoltaic modules are described. A three phase-microinverter receives direct current output generated by a microsystems-enabled photovoltaic cell and converts such direct current output into three-phase alternating current out. The three-phase microinverter is interleaved with other three-phase-microinverters, wherein such microinverters are integrated in a photovoltaic module with the microsystems-enabled photovoltaic cell.

A novel power converter for photovoltaic applications

Science.gov (United States)

Yuvarajan, S.; Yu, Dachuan; Xu, Shanguang

A simple and economical power conditioner to convert the power available from solar panels into 60 Hz ac voltage is described. The raw dc voltage from the solar panels is converted to a regulated dc voltage using a boost converter and a large capacitor and the dc output is then converted to 60 Hz ac using a bridge inverter. The ratio between the load current and the short-circuit current of a PV panel at maximum power point is nearly constant for different insolation (light) levels and this property is utilized in designing a simple maximum power point tracking (MPPT) controller. The controller includes a novel arrangement for sensing the short-circuit current without disturbing the operation of the PV panel and implementing MPPT. The switching losses in the inverter are reduced by using snubbers. The results obtained on an experimental converter are presented.

Does Your Domestic Photovoltaic Energy System Survive Grid Outages?

NARCIS (Netherlands)

Jongerden, M.R.; Hüls, Jannik; Remke, Anne Katharina Ingrid; Haverkort, Boudewijn R.H.M.

2016-01-01

Domestic renewable energy systems, including photovoltaic energy generation, as well as local storage, are becoming increasingly popular and economically feasible, but do come with a wide range of options. Hence, it can be difficult to match their specification to specific customer’s needs. Next to

Photovoltaics: US aims for zero-energy

International Nuclear Information System (INIS)

Barbose, G.; Wiser, R.; Bolinger, M.

2006-01-01

The strategies used in nine US states to support the use of photovoltaics (PV) in new market-rate homes are described. Standard buy-down programmes, the use of competitive bidding to support renewable energy technologies in larger projects, and general research and development funding for clean energy and green buildings are discussed. Targeted efforts to support PV in new houses, and market impacts are considered. Basic lessons learnt are outlined and include the need to track key information about PV installations in new dwellings, to ensure adequate funding, to consider higher incentive levels, coordinate PV and energy efficiency programmes, cultivate the installer infrastructure, educate key professionals, and engage the building community

Cycloidal Wave Energy Converter

Energy Technology Data Exchange (ETDEWEB)

Stefan G. Siegel, Ph.D.

2012-11-30

This program allowed further advancing the development of a novel type of wave energy converter, a Cycloidal Wave Energy Converter or CycWEC. A CycWEC consists of one or more hydrofoils rotating around a central shaft, and operates fully submerged beneath the water surface. It operates under feedback control sensing the incoming waves, and converts wave power to shaft power directly without any intermediate power take off system. Previous research consisting of numerical simulations and two dimensional small 1:300 scale wave flume experiments had indicated wave cancellation efficiencies beyond 95%. The present work was centered on construction and testing of a 1:10 scale model and conducting two testing campaigns in a three dimensional wave basin. These experiments allowed for the first time for direct measurement of electrical power generated as well as the interaction of the CycWEC in a three dimensional environment. The Atargis team successfully conducted two testing campaigns at the Texas A&M Offshore Technology Research Center and was able to demonstrate electricity generation. In addition, three dimensional wave diffraction results show the ability to achieve wave focusing, thus increasing the amount of wave power that can be extracted beyond what was expected from earlier two dimensional investigations. Numerical results showed wave cancellation efficiencies for irregular waves to be on par with results for regular waves over a wide range of wave lengths. Using the results from previous simulations and experiments a full scale prototype was designed and its performance in a North Atlantic wave climate of average 30kW/m of wave crest was estimated. A full scale WEC with a blade span of 150m will deliver a design power of 5MW at an estimated levelized cost of energy (LCOE) in the range of 10-17 US cents per kWh. Based on the new results achieved in the 1:10 scale experiments these estimates appear conservative and the likely performance at full scale will

Designing and Testing Composite Energy Storage Systems for Regulating the Outputs of Linear Wave Energy Converters

Directory of Open Access Journals (Sweden)

Zanxiang Nie

2017-01-01

Full Text Available Linear wave energy converters generate intrinsically intermittent power with variable frequency and amplitude. A composite energy storage system consisting of batteries and super capacitors has been developed and controlled by buck-boost converters. The purpose of the composite energy storage system is to handle the fluctuations and intermittent characteristics of the renewable source, and hence provide a steady output power. Linear wave energy converters working in conjunction with a system composed of various energy storage devices, is considered as a microsystem, which can function in a stand-alone or a grid connected mode. Simulation results have shown that by applying a boost H-bridge and a composite energy storage system more power could be extracted from linear wave energy converters. Simulation results have shown that the super capacitors charge and discharge often to handle the frequent power fluctuations, and the batteries charge and discharge slowly for handling the intermittent power of wave energy converters. Hardware systems have been constructed to control the linear wave energy converter and the composite energy storage system. The performance of the composite energy storage system has been verified in experiments by using electronics-based wave energy emulators.

Photovoltaic energy barometer

International Nuclear Information System (INIS)

Anon

2006-01-01

The european market showed all of its strength and soundness in 2005. The 2005 installed cells growth could have been even greater if the market had not been continually curbed by a lack of raw materials. Germany remained the leading photovoltaic market in the world in 2005, positioned far ahead of Japan and the USA. This unabashed success inspired both Spain and Italy, which set up conditions in order to rapidly develop their photovoltaic sectors. (A.L.B.)

Converters for Distributed Power Generation Systems

DEFF Research Database (Denmark)

Blaabjerg, Frede; Yang, Yongheng

2015-01-01

Power electronics technology has become the enabling technology for the integration of distributed power generation systems (DPGS) such as offshore wind turbine power systems and commercial photovoltaic power plants. Depending on the applications, a vast array of DPGS-based power converter...... topologies has been developed and more are coming into the market in order to achieve an efficient and reliable power conversion from the renewables. In addition, stringent demands from both the distribution system operators and the consumers have been imposed on the renewable-based DPGS. This article...... presents an overview of the power converters for the DPGS, mainly based on wind turbine systems and photovoltaic systems, covering a wide range of applications. Moreover, the modulation schemes and interfacing power filters for the power converters are also exemplified. Finally, the general control...

Modeling, control, and simulation of battery storage photovoltaic-wave energy hybrid renewable power generation systems for island electrification in Malaysia.

Science.gov (United States)

Samrat, Nahidul Hoque; Bin Ahmad, Norhafizan; Choudhury, Imtiaz Ahmed; Bin Taha, Zahari

2014-01-01

Today, the whole world faces a great challenge to overcome the environmental problems related to global energy production. Most of the islands throughout the world depend on fossil fuel importation with respect to energy production. Recent development and research on green energy sources can assure sustainable power supply for the islands. But unpredictable nature and high dependency on weather conditions are the main limitations of renewable energy sources. To overcome this drawback, different renewable sources and converters need to be integrated with each other. This paper proposes a standalone hybrid photovoltaic- (PV-) wave energy conversion system with energy storage. In the proposed hybrid system, control of the bidirectional buck-boost DC-DC converter (BBDC) is used to maintain the constant dc-link voltage. It also accumulates the excess hybrid power in the battery bank and supplies this power to the system load during the shortage of hybrid power. A three-phase complex vector control scheme voltage source inverter (VSI) is used to control the load side voltage in terms of the frequency and voltage amplitude. Based on the simulation results obtained from Matlab/Simulink, it has been found that the overall hybrid framework is capable of working under the variable weather and load conditions.

Evaluation of a photovoltaic energy mechatronics system with a built-in quadratic maximum power point tracking algorithm

Energy Technology Data Exchange (ETDEWEB)

Chao, R.M.; Ko, S.H.; Lin, I.H. [Department of Systems and Naval Mechatronics Engineering, National Cheng Kung University, Tainan, Taiwan 701 (China); Pai, F.S. [Department of Electronic Engineering, National University of Tainan (China); Chang, C.C. [Department of Environment and Energy, National University of Tainan (China)

2009-12-15

The historically high cost of crude oil price is stimulating research into solar (green) energy as an alternative energy source. In general, applications with large solar energy output require a maximum power point tracking (MPPT) algorithm to optimize the power generated by the photovoltaic effect. This work aims to provide a stand-alone solution for solar energy applications by integrating a DC/DC buck converter to a newly developed quadratic MPPT algorithm along with its appropriate software and hardware. The quadratic MPPT method utilizes three previously used duty cycles with their corresponding power outputs. It approaches the maximum value by using a second order polynomial formula, which converges faster than the existing MPPT algorithm. The hardware implementation takes advantage of the real-time controller system from National Instruments, USA. Experimental results have shown that the proposed solar mechatronics system can correctly and effectively track the maximum power point without any difficulties. (author)

Subcutaneous Photovoltaic Infrared Energy Harvesting for Bio-Implantable Devices.

Science.gov (United States)

Moon, Eunseong; Blaauw, David; Phillips, Jamie D

2017-05-01

Wireless biomedical implantable devices on the mm-scale enable a wide range of applications for human health, safety, and identification, though energy harvesting and power generation are still looming challenges that impede their widespread application. Energy scavenging approaches to power biomedical implants have included thermal [1-3], kinetic [4-6], radio-frequency [7-11] and radiative sources [12-14]. However, the achievement of efficient energy scavenging for biomedical implants at the mm-scale has been elusive. Here we show that photovoltaic cells at the mm-scale can achieve a power conversion efficiency of more than 17 % for silicon and 31 % for GaAs under 1.06 μW/mm 2 infrared irradiation at 850 nm. Finally, these photovoltaic cells demonstrate highly efficient energy harvesting through biological tissue from ambient sunlight, or irradiation from infrared sources such as used in present-day surveillance systems, by utilizing the near infrared (NIR) transparency window between the 650 nm and 950 nm wavelength range [15-17].

Modular Power Electronic Converters in the Power Range 1 to 10 kW

DEFF Research Database (Denmark)

Klimczak, Pawel

Thanks to CO2 emission reduction policies and increasing prices of fossil fuels a significant growth in field of sustainable energy sources (SES) is being observed during last decade. A government support and take-off projects in Europe and US shall ensure an increasing trend in future too. Some...... of SES based plants , like hydro-, geothermal-, biofuel-plants, use synchronous generators directly connected to the grid. But some other SES technologies, like fuel cell or photovoltaic, require a power electronic converter between the energy source and the load or the grid. Work presented...... in this thesis concentrates on dc-dc non-isolated converters suitable for high voltage gain applications, like uninterruptible power supply (UPS) and some of sustainable energy sources. A special attention is on reduction of power losses and efficiency improvements in non-isolated dc-dc step-up converters...

Interim performance criteria for photovoltaic energy systems. [Glossary included

Energy Technology Data Exchange (ETDEWEB)

DeBlasio, R.; Forman, S.; Hogan, S.; Nuss, G.; Post, H.; Ross, R.; Schafft, H.

1980-12-01

This document is a response to the Photovoltaic Research, Development, and Demonstration Act of 1978 (P.L. 95-590) which required the generation of performance criteria for photovoltaic energy systems. Since the document is evolutionary and will be updated, the term interim is used. More than 50 experts in the photovoltaic field have contributed in the writing and review of the 179 performance criteria listed in this document. The performance criteria address characteristics of present-day photovoltaic systems that are of interest to manufacturers, government agencies, purchasers, and all others interested in various aspects of photovoltaic system performance and safety. The performance criteria apply to the system as a whole and to its possible subsystems: array, power conditioning, monitor and control, storage, cabling, and power distribution. They are further categorized according to the following performance attributes: electrical, thermal, mechanical/structural, safety, durability/reliability, installation/operation/maintenance, and building/site. Each criterion contains a statement of expected performance (nonprescriptive), a method of evaluation, and a commentary with further information or justification. Over 50 references for background information are also given. A glossary with definitions relevant to photovoltaic systems and a section on test methods are presented in the appendices. Twenty test methods are included to measure performance characteristics of the subsystem elements. These test methods and other parts of the document will be expanded or revised as future experience and needs dictate.

Feasibility Study of Seawater Electrolysis for Photovoltaic/Fuel Cell Hybrid Power System for the Coastal Areas in Thailand

Science.gov (United States)

Srisiriwat, A.; Pirom, W.

2017-10-01

Solar photovoltaic cell and fuel cell are the practicable options to realize as a possible hybrid power system because the power of the sun cannot be utilized at night or cloudy days but hydrogen has been found as an ideal energy carrier for being transportable, storable, and converting energy though fuel cell. Hydrogen storage is chosen for its ability to obtain a clean energy option. Electrolysis, which is the simplest process to produce hydrogen, can be powered by the dc voltage from the photovoltaic cell instead of using the battery as power supply. This paper concentrates on a feasibility study of seawater electrolysis using photovoltaic power integrated fuel cell system for the coastal cities in Thailand. The proposed system composed of photovoltaic arrays, seawater electrolyzer and fuel cell is presented when the 10-kW of fuel cell electrical power is considered. The feasibility study of hydrogen production and energy analysis of this proposed system is also evaluated.

Improvement of Shade Resilience in Photovoltaic Modules Using Buck Converters in a Smart Module Architecture

NARCIS (Netherlands)

Golroodbari, S. Mirbagheri; Waal, Arjen. de; Sark, Wilfried van

2018-01-01

Partial shading has a nonlinear effect on the performance of photovoltaic (PV) modules. Different methods of optimizing energy harvesting under partial shading conditions have been suggested to mitigate this issue. In this paper, a smart PV module architecture is proposed for improvement of shade

Experimental Study on the Langlee Wave Energy Converter

DEFF Research Database (Denmark)

Lavelle, John; Kofoed, Jens Peter

This report concerns the experimental study of the 1:20 scale model of the Langlee Wave Energy Converter (WEC) carried out at Aalborg University’s wave basin during the summer of 2010.......This report concerns the experimental study of the 1:20 scale model of the Langlee Wave Energy Converter (WEC) carried out at Aalborg University’s wave basin during the summer of 2010....

Photovoltaics and renewable energies in Europe

International Nuclear Information System (INIS)

Jaeger-Waldau, Arnulf

2007-01-01

Photovoltaics and renewable energies are growing at a much faster pace than the rest of the economy in Europe and worldwide. This and the dramatic oil price increases in 2005 have led to a remarkable re-evaluation of the renewable energy sector by politics and financing institutions. Despite the fact that there are still discrepancies between the European Union and the USA, as to how to deal with climate change, renewable energies will play an important role for the implementation of the Kyoto Protocol and the worldwide introduction of tradable Green Certificates. Apart from the electricity sector, renewable energy sources for the generation of heat and the use of environment friendly biofuels for the transport sector will become more and more important in the future. (author)

Solar Energy Technician/Installer

Science.gov (United States)

Moore, Pam

2007-01-01

Solar power (also known as solar energy) is solar radiation emitted from the sun. Large panels that absorb the sun's energy as the sun beats down on them gather solar power. The energy in the rays can be used for heat (solar thermal energy) or converted to electricity (photovoltaic energy). Each solar energy project, from conception to…

Thermoelectric cooling in combination with photovoltaics and thermal energy storage

Directory of Open Access Journals (Sweden)

Skovajsa Jan

2017-01-01

Full Text Available The article deals with the use of modern technologies that can improve the thermal comfort in buildings. The article describes the usage of thermal energy storage device based on the phase change material (PCM. The technology improves the thermal capacity of the building and it is possible to use it for active heating and cooling. It is designed as a “green technology” so it is able to use renewable energy sources, e.g., photovoltaic panels, solar thermal collectors, and heat pump. Moreover, an interesting possibility is the ability to use thermal energy storage in combination with a photovoltaic system and thermoelectric coolers. In the research, there were made measurements of the different operating modes and the results are presented in the text.

An innovative thermodynamic model for performance evaluation of photovoltaic systems: Effect of wind speed and cell temperature

International Nuclear Information System (INIS)

Kaushik, S.C.; Rawat, Rahul; Manikandan, S.

2017-01-01

Highlights: • A novel thermodynamic modelling of photovoltaic energy system has been proposed. • The entropy, optical, thermal, spectral and fill factor losses are assessed. • The expression of energetic and exergetic efficiencies have been derived. • Reversible, endoreversible, exoreversible and irreversible systems are presented. - Abstract: The photovoltaic energy conversion is a thermodynamic system which converts the solar energy to the electrical and thermal energy. In this paper, a novel thermodynamic model of photovoltaic energy conversion system has been proposed on the basis of the first and second law of thermodynamics including entropy generation, optical, thermal, spectral and fill factor losses. Based on the irreversibilities, the proposed model has been classified into four cases i.e. reversible, endoreversible, exoreversible and irreversible systems, for which, the expressions of energetic and exergetic efficiencies have been derived. The upper limit efficiency of an ideal photovoltaic module placed in an irreversible environment, i.e. endoreversible system, is determined to be 82.8%. The effect of wind speed and module temperature on the energetic and exergetic efficiencies, thermodynamic losses and irreversibilities has also been presented.

High Step-Up DC—DC Converter for AC Photovoltaic Module with MPPT Control

Science.gov (United States)

Sundar, Govindasamy; Karthick, Narashiman; Rama Reddy, Sasi

2014-08-01

This paper presents the high gain step-up BOOST converter which is essential to step up the low output voltage from PV panel to the high voltage according to the requirement of the application. In this paper a high gain BOOST converter with coupled inductor technique is proposed with the MPPT control. Without extreme duty ratios and the numerous turns-ratios of a coupled inductor this converter achieves a high step-up voltage-conversion ratio and the leakage energy of the coupled inductor is efficiently recycled to the load. MPPT control used to extract the maximum power from PV panel by controlling the Duty ratio of the converter. The PV panel, BOOST converter and the MPPT are modeled using Sim Power System blocks in MATLAB/SIMULINK environment. The prototype model of the proposed converter has been implemented with the maximum measured efficiency is up to 95.4% and full-load efficiency is 93.1%.

Electrostatic direct energy converter performance and cost scaling laws

International Nuclear Information System (INIS)

Hoffman, M.A.

1977-08-01

This study is concerned with electrostatic type direct energy converters for direct recovery of a large fraction of the plasma ion energy from fusion reactors. Simplified equations are presented for each of the important loss mechanisms in both single-stage direct converters and multistage ''Venetian Blind'' type direct converters. These equations can be used to estimate the efficiency and electric power output of the direct converter subsystem. Scaling relations for the cost of each major component in the direct converter subsystem are also given; these include the vacuum tank, direct converter modules, the DC power conditioning equipment, cryogenic vacuum pumping system and the thermal bottoming plant. The performance and cost scaling laws have been developed primarily for use in overall fusion power plant systems codes. However, to illustrate their utility, cost-effectiveness studies of two specific reference direct converter designs are presented in terms of the specific capital costs (i.e., the capital cost per unit electric power produced) for the Direct Converter Subsystem alone. Some examples of design improvements which can significantly reduce the specific capital costs of the Direct Converter Subsystem are also given

Design Specifications for the Hanstholm WEPTOS Wave Energy Converter

DEFF Research Database (Denmark)

Pecher, Arthur; Kofoed, Jens Peter; Larsen, Tommy

2012-01-01

The WEPTOS wave energy converter (WEC) is a novel device that combines an established and efficient wave energy absorbing mechanism with a smart structure, which can regulate the amount of incoming wave energy and reduce loads in extreme wave conditions. This adjustable A-shaped slack-moored and ......The WEPTOS wave energy converter (WEC) is a novel device that combines an established and efficient wave energy absorbing mechanism with a smart structure, which can regulate the amount of incoming wave energy and reduce loads in extreme wave conditions. This adjustable A-shaped slack...

Multistage switched inductor boost converter for renewable energy application

DEFF Research Database (Denmark)

Maroti, Pandav Kiran; Padmanaban, Sanjeevikumar; Bhaskar, Mahajan Sagar

2017-01-01

In this paper Multistage Switched Inductor Boost Converter (Multistage SIBC) is uttered for renewable energy applications. The projected converter is derived from an amalgamation of the conventional step-up converter and inductor stack. The number of inductor and duty ratio decides the overall...

Classification of methods for annual energy harvesting calculations of photovoltaic generators

International Nuclear Information System (INIS)

Rus-Casas, C.; Aguilar, J.D.; Rodrigo, P.; Almonacid, F.; Pérez-Higueras, P.J.

2014-01-01

Highlights: • The paper presents a novel classification of methods for annual energy harvesting calculation of grid-connected PV systems. • The methods are classified in direct and indirect methods. • Direct methods directly calculate the energy. Indirect methods calculate the energy from the power. • The classification can help the PV professionals in order to choose the most suitable method for each application. - Abstract: Estimating the energy provided by the generators of grid-connected photovoltaic systems is important in order to analyze their economic viability and supervise their operation. The energy harvesting calculation of a photovoltaic generator is not trivial; there are a lot of methods for this calculation. The aim of this paper is to develop a novel classification of methods for annual energy harvesting calculation of a generator of a grid-connected photovoltaic system. The methods are classified in two groups: (1) those that indirectly calculate the energy, i.e. they first calculate the power and from this, they calculate the energy, and (2) those that directly calculate the energy. Furthermore, the indirect methods are grouped in two categories: those that first calculate the I–V curve of the generator and from this, they calculate the power, and those that directly calculate the power. The study has shown that the existing methods differ in simplicity and accuracy, so that the proposed classification is useful in order to choose the most suitable method for each specific application

Materials for thermionic energy converters

NARCIS (Netherlands)

Wolff, L.R.; Hermans, J.M.; Adriaansen, J.K.M.; Gubbels, G.H.M.; Vincenzini, P.

1987-01-01

This paper deals with the design and construction of a combustion heated Thermionic Energy Converter (TEC). Main components of this TEC are: 1. A ''Hot Shell'' protecting the TEC from the combustion environment 2. A ''Ceramic Seal'' electrically insulating the emitter from the collector 3. A

Press document. Photovoltaic energy: boosting the evolution; Dossier de presse. Photovoltaique: accelerer l'innovation

Energy Technology Data Exchange (ETDEWEB)

NONE

2009-04-15

The french potential in the photovoltaic energy is considerable but not very exploited. In this context the CEA, by its function of applied research institute in the domain of the low carbon energies can be a major actor of the sector development. This document presents the research programs in the photovoltaic domain, developed at the CEA, especially on the silicon performance, the photovoltaic solar cells and their integration in the buildings. (A.L.B.)

Levelized Cost of Energy of the Weptos wave energy converter

DEFF Research Database (Denmark)

Pecher, Arthur; Kofoed, Jens Peter

This report presents the cost of energy calculations of a wave energy array of 90 MW, consisting of 25 x 3.6 MW Weptos wave energy converters. The calculation has been made in analogy with a publically available document presented by the UK government, covering the case of a similar size wind...

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.

Hybrid energy converter based on swirling combustion chambers: the hydrocarbon feeding analysis

Directory of Open Access Journals (Sweden)

Angelo Minotti

2017-05-01

Full Text Available This manuscript reports the latest investigations about a miniaturized hybrid energy power source, compatible with thermal/electrical conversion, by a thermo-photovoltaic cell, and potentially useful for civil and space applications. The converter is a thermally-conductive emitting parallelepiped element and the basic idea is to heat up its emitting surfaces by means of combustion, occurred in swirling chambers, integrated inside the device, and/or by the sun, which may work simultaneously or alternatively to the combustion. The current upgrades consist in examining whether the device might fulfill specific design constraints, adopting hydrocarbons-feeding. Previous papers, published by the author, demonstrate the hydrogen-feeding effectiveness. The project’s constraints are: 1 emitting surface dimensions fixed to 30 × 30 mm, 2 surface peak temperature T > 1000 K and the relative ∆T < 100 K (during the combustion mode, 3 the highest possible delivered power to the ambient, and 4 thermal efficiency greater than 20% when works with solar energy. To this end, a 5 connected swirling chambers configuration (3 mm of diameter, with 500 W of injected chemical power, stoichiometric conditions and detailed chemistry, has been adopted. Reactive numerical simulations show that the stiff methane chemical structure obliges to increase the operating pressure, up to 10 atm, and to add hydrogen, to the methane fuel injection, in order to obtain stable combustion and efficient energy conversion.

Municipal programs of photovoltaic energy development; Les programmes municipaux de developpement du photovoltaique

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-07-01

This study presents some remarkable actions carried out in several European municipalities for the promotion and development of photovoltaic applications: installation of solar cells on public buildings, integration of the photovoltaic energy in the urban plan, application in the transportation sector, programs of public information, of promotion, of incitation, of financing, solar electricity trade, promotion of the 'green current'. After a presentation of the general situation of photovoltaic energy in Europe, and of its development in France, nine case-forms present the experience of nine selected European cities in this domain (Amersfoort (NL), Barcelona (ES), Braedstrup (DK), Karlsruhe (DE), Lausanne (CH), Mataro (ES), Muenchen (ES), Palermo (IT), Zurich (CH)). (J.S.)

A soft-switching coupled inductor bidirectional DC-DC converter with high-conversion ratio

Science.gov (United States)

Chao, Kuei-Hsiang; Jheng, Yi-Cing

2018-01-01

A soft-switching bidirectional DC-DC converter is presented herein as a way to improve the conversion efficiency of a photovoltaic (PV) system. Adoption of coupled inductors enables the presented converter not only to provide a high-conversion ratio but also to suppress the transient surge voltage via the release of the energy stored in leakage flux of the coupled inductors, and the cost can kept down consequently. A combined use of a switching mechanism and an auxiliary resonant branch enables the converter to successfully perform zero-voltage switching operations on the main switches and improves the efficiency accordingly. It was testified by experiments that our proposed converter works relatively efficiently in full-load working range. Additionally, the framework of the converter intended for testifying has high-conversion ratio. The results of a test, where a generating system using PV module array coupled with batteries as energy storage device was used as the low-voltage input side, and DC link was used as high-voltage side, demonstrated our proposed converter framework with high-conversion ratio on both high-voltage and low-voltage sides.

Overview of renewable energies during the first six-month period of 2013. Wind energy, Photovoltaic energy, Connection schemes (S3REnR)

International Nuclear Information System (INIS)

2013-01-01

Illustrated by maps, graphs and tables, the first part of this document presents and comments data related to wind energy production. It addresses the status of the wind energy production stock (connected stock in June 2013, regional distribution, distribution in terms of power range, evolution of wind turbine and wind farm power), growth perspectives, and the role of wind energy production in the supply-demand balance (production and load factor, regional distribution of production and load factor, share in consumption coverage, wind energy production flow management). Using the same kind of presentation and the same issues, the second part presents and comments data related to photovoltaic energy production in France: photovoltaic stock (connected stock in June 2013, regional distribution, distribution in terms of power range), growth perspectives, and role of photovoltaic energy production in the supply-demand balance (production and load factor, production and load factor regional distribution, role in consumption coverage). The third part briefly presents data related to Regional Schemes of Connection to the renewable energy network (S3REnR) which ensure conditions of connection to the electric grid of all renewable energies

Diverting indirect subsidies from the nuclear industry to the photovoltaic industry: Energy and financial returns

International Nuclear Information System (INIS)

Zelenika-Zovko, I.; Pearce, J.M.

2011-01-01

Nuclear power and solar photovoltaic energy conversion often compete for policy support that governs economic viability. This paper compares current subsidization of the nuclear industry with providing equivalent support to manufacturing photovoltaic modules. Current U.S. indirect nuclear insurance subsidies are reviewed and the power, energy and financial outcomes of this indirect subsidy are compared to equivalent amounts for indirect subsidies (loan guarantees) for photovoltaic manufacturing using a model that holds economic values constant for clarity. The preliminary analysis indicates that if only this one relatively ignored indirect subsidy for nuclear power was diverted to photovoltaic manufacturing, it would result in more installed power and more energy produced by mid-century. By 2110 cumulative electricity output of solar would provide an additional 48,600 TWh over nuclear worth $5.3 trillion. The results clearly show that not only does the indirect insurance liability subsidy play a significant factor for nuclear industry, but also how the transfer of such an indirect subsidy from the nuclear to photovoltaic industry would result in more energy over the life cycle of the technologies. - Highlights: → The indirect insurance liability subsidy has been quantified over the life cycle of the U.S. nuclear fleet. → It was found to play a significant factor in the economics of the nuclear industry. → A transfer of such an indirect subsidy from the nuclear to photovoltaic industry would result in significantly more energy over the life cycle of the technologies.

Observatory of photovoltaic solar energy in France - 20. edition

International Nuclear Information System (INIS)

2016-12-01

After an overview of important events in the World regarding the development of photovoltaic solar energy in 2016, and predictions regarding new connected installations in 2016, this document present graphs and figures which illustrate the evolution of the photovoltaic fleet in the World, the comparison of production costs of new electric power generation capacities, the evolution of the French photovoltaic power production since 2009, the evolution of the distribution of the French fleet in terms of installation power (from large projects to residential), of connections to the grid, of number of connections and purchase tariffs for the different types of installations (residential, medium roofs, large roofs, very large roofs, very large ground-based or roof-based projects) and for queuing projects, in terms of evolution of purchase tariffs since 2011, and of evolution of impact on the CSPE financing system

An Innovative Reconfigurable Integrated Converter Topology Suitable for Distributed Generation

Directory of Open Access Journals (Sweden)

Renato Rizzo

2012-09-01

Full Text Available The electricity market and environmental concerns, with wide utilization of renewable sources, have improved the diffusion of distributed generation units changing the operations of distribution grids from passive networks to microgrids. A microgrid includes a cluster of electrical loads, energy storage devices and microsources, which provide both power and heat to their local area. A microgrid has usually one connection point to the utility grid through power electronic converters placed at customers’ sites. This paper analyses a Reconfigurable Integrated Converter (RIC used for a domestic microgrid with inputs from the AC mains and photovoltaic arrays, and two DC outputs at different voltage levels. A RIC as a dual-boost DC-DC converter is proposed, modelled and analysed in the paper. The advantages of such a topology in comparison with traditional boost converters are outlined. Reported simulations results give evidence on the controllability of this converter and the capability of achieving the desired voltage outputs with reduced ripple.

State estimation for wave energy converters

Energy Technology Data Exchange (ETDEWEB)

Bacelli, Giorgio; Coe, Ryan Geoffrey

2017-04-01

This report gives a brief discussion and examples on the topic of state estimation for wave energy converters (WECs). These methods are intended for use to enable real-time closed loop control of WECs.

Power electronics and control techniques for maximum energy harvesting in photovoltaic systems

CERN Document Server

Femia, Nicola

2012-01-01

Incentives provided by European governments have resulted in the rapid growth of the photovoltaic (PV) market. Many PV modules are now commercially available, and there are a number of power electronic systems for processing the electrical power produced by PV systems, especially for grid-connected applications. Filling a gap in the literature, Power Electronics and Control Techniques for Maximum Energy Harvesting in Photovoltaic Systems brings together research on control circuits, systems, and techniques dedicated to the maximization of the electrical power produced by a photovoltaic (PV) so

Photovoltaic solar energy: State of the art

International Nuclear Information System (INIS)

Van Sark, W.G.J.H.M.; Sinke, W.C.

1993-03-01

Attention is paid to developments in the Netherlands of all aspects of photovoltaic (PV) energy: solar cells, components, PV-systems and all kinds of applications. Efficiencies of the present solar cell types still increase, varying from more than 10% for organic/TiO 2 solar cells to 33% for GaAs/GaSb concentrator tandem solar cells. 3 figs., 2 ills., 1 tab

Power fluctuations suppression of stand-alone hybrid generation combining solar photovoltaic/wind turbine and fuel cell systems

International Nuclear Information System (INIS)

Ahmed, Nabil A.; Miyatake, Masafumi; Al-Othman, A.K.

2008-01-01

In this paper a hybrid energy system combining variable speed wind turbine, solar photovoltaic and fuel cell generation systems is presented to supply continuous power to residential power applications as stand-alone loads. The wind and photovoltaic systems are used as main energy sources while the fuel cell is used as secondary or back-up energy source. Three individual dc-dc boost converters are used to control the power flow to the load. A simple and cost effective control with dc-dc converters is used for maximum power point tracking and hence maximum power extracting from the wind turbine and the solar photovoltaic systems. The hybrid system is sized to power a typical 2 kW/150 V dc load as telecommunication power plants or ac residential power applications in isolated islands continuously throughout the year. The results show that even when the sun and wind are not available; the system is reliable and available and it can supply high-quality power to the load. The simulation results which proved the accuracy of the proposed controllers are given to demonstrate the availability of the proposed system in this paper. Also, a complete description of the management and control system is presented

Bidirectional converter interface for a battery energy storage test bench

DEFF Research Database (Denmark)

Trintis, Ionut; Thomas, Stephan; Blank, Tobias

2011-01-01

This paper presents the bidirectional converter interface for a 6 kV battery energy storage test bench. The power electronic interface consists a two stage converter topology having a low voltage dc-ac grid connected converter and a new dual active bridge dc-dc converter with high transformation...

A search for space energy alternatives

Science.gov (United States)

Gilbreath, W. P.; Billman, K. W.

1978-01-01

This paper takes a look at a number of schemes for converting radiant energy in space to useful energy for man. These schemes are possible alternatives to the currently most studied solar power satellite concept. Possible primary collection and conversion devices discussed include the space particle flux devices, solar windmills, photovoltaic devices, photochemical cells, photoemissive converters, heat engines, dielectric energy conversion, electrostatic generators, plasma solar collectors, and thermionic schemes. Transmission devices reviewed include lasers and masers.

Energy harvesting using TEG and PV cell for low power application

Science.gov (United States)

Tawil, Siti Nooraya Mohd; Zainal, Mohd Zulkarnain

2018-02-01

A thermoelectric generator (TEG) module and photovoltaic cell (PV) were utilized to harvest energy from temperature gradients of heat sources from ambient heat and light of sun. The output of TEG and PV were connected to a power management circuit consist of step-up dc-dc converter in order to increase the output voltage to supply a low power application such as wireless communication module and the photovoltaic cell for charging an energy storage element in order to switch on a fan for cooling system of the thermoelectric generator. A switch is used as a selector to choose the input of source either from photovoltaic cell or thermoelectric generator to switch on DC-DC step-up converter. In order to turn on the DC-DC step-up converter, the input must be greater than 3V. The energy harvesting was designed so that it can be used continuously and portable anywhere. Multiple sources used in this energy harvesting system is to ensure the system can work in whatever condition either in good weather or not good condition of weather. This energy harvesting system has the potential to be used in military operation and environment that require sustainability of energy resources.

Design and development of hybrid energy generator (photovoltaics) with solar tracker

Science.gov (United States)

Mohiuddin, A. K. M.; Sabarudin, Mohamad Syabil Bin; Khan, Ahsan Ali; Izan Ihsan, Sany

2017-03-01

This paper is the outcome of a small scale hybrid energy generator (hydro and photovoltaic) project. It contains the photovoltaics part of the project. The demand of energy resources is increasing day by day. That is why people nowadays tend to move on and changes their energy usage from using fossil fuels to a cleaner and green energy like hydro energy, solar energy etc. Nevertheless, energy is hard to come by for people who live in remote areas and also campsites in the remote areas which need continuous energy sources to power the facilities. Thus, the purpose of this project is to design and develop a small scale hybrid energy generator to help people that are in need of power. This main objective of this project is to develop and analyze the effectiveness of solar trackers in order to increase the electricity generation from solar energy. Software like Solidworks and Arduino is used to sketch and construct the design and also to program the microcontroller respectively. Experimental results show the effectiveness of the designed solar tracker sytem.

Municipal programs of photovoltaic energy development; Les programmes municipaux de developpement du photovoltaique

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-07-01

This study presents some remarkable actions carried out in several European municipalities for the promotion and development of photovoltaic applications: installation of solar cells on public buildings, integration of the photovoltaic energy in the urban plan, application in the transportation sector, programs of public information, of promotion, of incitation, of financing, solar electricity trade, promotion of the 'green current'. After a presentation of the general situation of photovoltaic energy in Europe, and of its development in France, nine case-forms present the experience of nine selected European cities in this domain (Amersfoort (NL), Barcelona (ES), Braedstrup (DK), Karlsruhe (DE), Lausanne (CH), Mataro (ES), Muenchen (ES), Palermo (IT), Zurich (CH)). (J.S.)

Photovoltaic and thermal energy conversion for solar powered satellites

Science.gov (United States)

Von Tiesenhausen, G. F.

1976-01-01

A summary is provided concerning the most important aspects of present investigations related to a use of solar power satellites (SPS) as a future source of terrestrial energy. General SPS characteristics are briefly considered, early work is reviewed, and a description of current investigations is presented. System options presently under study include a photovoltaic array, a thermionic system, and a closed Brayton cycle. Attention is given to system reference options, basic building blocks, questions of system analysis and engineering, photovoltaic conversion, and the utility interface. It is concluded that an SPS may be cost effective compared to terrestrial systems by 1995.

Silicon nanowires for photovoltaic solar energy conversion.

Science.gov (United States)

Peng, Kui-Qing; Lee, Shuit-Tong

2011-01-11

Semiconductor nanowires are attracting intense interest as a promising material for solar energy conversion for the new-generation photovoltaic (PV) technology. In particular, silicon nanowires (SiNWs) are under active investigation for PV applications because they offer novel approaches for solar-to-electric energy conversion leading to high-efficiency devices via simple manufacturing. This article reviews the recent developments in the utilization of SiNWs for PV applications, the relationship between SiNW-based PV device structure and performance, and the challenges to obtaining high-performance cost-effective solar cells.

Grid Converters for Stationary Battery Energy Storage Systems

DEFF Research Database (Denmark)

Trintis, Ionut

The integration of renewable energy sources in the power system, with high percentage, is a well known challenge nowadays. Power sources like wind and solar are highly volatile, with uctuations on various time scales. One long term solution is to build a continentwide or worldwide supergrid....... Another solution is to use distributed energy storage units, and create virtual power plants. Stationary energy storage is a complementary solution, which can postpone the network expansion and can be optimized for dierent kind of grid services. As an energy storage solution with timing for few seconds...... multilevel converter structure with integrated energy storage is introduced. This converter structure is suitable to interface low and medium voltage energy storage units to medium and high voltage grids. It can also interconnect a DC and AC grid with bidirectional power ow, were both can be backed...

Economic reassessment of energy technologies with risk-management techniques

International Nuclear Information System (INIS)

Mohr, Markus; Unger, Hermann

1999-01-01

A new approach for the reassessment of modern energy technologies is discussed. This mainly addresses renewable-energy systems, like photovoltaics or wind converters. A new number called the 'Marginal Energy Risk Price (MERP) for Hedging' is introduced. (Author)

Graphene-Based Integrated Photovoltaic Energy Harvesting/Storage Device.

Science.gov (United States)

Chien, Chih-Tao; Hiralal, Pritesh; Wang, Di-Yan; Huang, I-Sheng; Chen, Chia-Chun; Chen, Chun-Wei; Amaratunga, Gehan A J

2015-06-24

Energy scavenging has become a fundamental part of ubiquitous sensor networks. Of all the scavenging technologies, solar has the highest power density available. However, the energy source is erratic. Integrating energy conversion and storage devices is a viable route to obtain self-powered electronic systems which have long-term maintenance-free operation. In this work, we demonstrate an integrated-power-sheet, consisting of a string of series connected organic photovoltaic cells (OPCs) and graphene supercapacitors on a single substrate, using graphene as a common platform. This results in lighter and more flexible power packs. Graphene is used in different forms and qualities for different functions. Chemical vapor deposition grown high quality graphene is used as a transparent conductor, while solution exfoliated graphene pastes are used as supercapacitor electrodes. Solution-based coating techniques are used to deposit the separate components onto a single substrate, making the process compatible with roll-to-roll manufacture. Eight series connected OPCs based on poly(3-hexylthiophene)(P3HT):phenyl-C61-butyric acid methyl ester (PC60 BM) bulk-heterojunction cells with aluminum electrodes, resulting in a ≈5 V open-circuit voltage, provide the energy harvesting capability. Supercapacitors based on graphene ink with ≈2.5 mF cm(-2) capacitance provide the energy storage capability. The integrated-power-sheet with photovoltaic (PV) energy harvesting and storage functions had a mass of 0.35 g plus the substrate. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Aquabuoy Wave Energy Converter

DEFF Research Database (Denmark)

Vicinanza, Diego; Margheritini, Lucia; Frigaard, Peter

The work reported here is part of the contract agreement between the Finavera Renewables Ocean Energy Ltd. and the Department of Civil Engineering Hydraulics and Coastal Engineering Laboratory to instrument a model in scale 1:10 to prototype of the AquaBuOY (AB) wave energy converter and to analyse...... its performances in real sea testing in Nissum Bredning, Denmark. This report is part of Fineveras contribution to ForskEl project no 6435 “AquaBuOY skala 1:10 forsøg I Nissum Bredning”....

Performance Analysis of a Photovoltaic-Thermal Integrated System

International Nuclear Information System (INIS)

Radziemska, E.

2009-01-01

The present commercial photovoltaic solar cells (PV) converts solar energy into electricity with a relatively low efficiency, less than 20%. More than 80% of the absorbed solar energy is dumped to the surroundings again after photovoltaic conversion. Hybrid PV/T systems consist of PV modules coupled with the heat extraction devices. The PV/T collectors generate electric power and heat simultaneously. Stabilizing temperature of photovoltaic modules at low level is highly desirable to obtain efficiency increase. The total efficiency of 60-80% can be achieved with the whole PV/T system provided that the T system is operated near ambient temperature. The value of the low-T heat energy is typically much smaller than the value of the PV electricity. The PV/T systems can exist in many designs, but the most common models are with the use of water or air as a working fuid. Efficiency is the most valuable parameter for the economic analysis. It has substantial meaning in the case of installations with great nominal power, as air-cooled Building Integrated Photovoltaic Systems (BIPV). In this paper the performance analysis of a hybrid PV/T system is presented: an energetic analysis as well as an exergetic analysis. Exergy is always destroyed when a process involves a temperature change. This destruction is proportional to the entropy increase of the system together with its surroundings the destroyed exergy has been called energy. Exergy analysis identifies the location, the magnitude, and the sources of thermodynamic inefficiencies in a system. This information, which cannot be provided by other means (e.g., an energy analysis), is very useful for the improvement and cost-effectiveness of the system. Calculations were carried out for the tested water-cooled ASE-100-DGL-SM Solar watt module.

A wideband fractal-inspired piezoelectric energy converter: design, simulation and experimental characterization

International Nuclear Information System (INIS)

Castagnetti, Davide

2013-01-01

In order to develop self-powered wireless sensor nodes, many energy harvesting devices that are able to convert available ambient energy into electrical energy have been proposed in the literature. A promising technique, in terms of simplicity and high conversion efficiency, is the harvesting of ambient kinetic energy through piezoelectric materials. The aim of this work is to design and investigate the modal response and power output of a fractal-inspired, multi-frequency, piezoelectric energy converter. The converter is a square, thin sheet structure, characterized by a fractal geometry obtained through a pattern of cuts in the plate. There are two steps involved. First, a computational analysis of the converter is performed. Second, a physical prototype of the converter is built and its eigenfrequencies and power generation under different resistive loads are experimentally examined in the range from 0 to 120 Hz. The converter exhibits three eigenfrequencies and a good power output, particularly at the first eigenfrequency. (paper)

Single stage grid converters for battery energy storage

DEFF Research Database (Denmark)

Trintis, Ionut; Munk-Nielsen, Stig; Teodorescu, Remus

2010-01-01

Integration of renewable energy systems in the power system network such as wind and solar is still a challenge in our days. Energy storage systems (ESS) can overcome the disadvantage of volatile generation of the renewable energy sources. This paper presents power converters for battery energy...

Photovoltaics: Energy for the New Millenium

Science.gov (United States)

Surek, Thomas

2000-04-01

Photovoltaics (PV) is a semiconductor-based technology that directly converts sunlight to electricity. The stimulus for terrestrial PV started more than 25 years ago in response to the oil crises of the 1970s, which resulted in major government programs in the United States, Europe, Japan, and elsewhere. Ongoing concerns with the global environment, as well as the worldwide efforts to seek alternate, indigenous sources of energy, continue to drive the investment in PV research and deployment. Today, the manufacture, sale, and use of PV has become a billion-dollar industry worldwide, with nearly 200 megawatts (MW) of PV modules shipped in 1999. The twenty five years of research and development led to the discovery of new PV materials, devices, and fabrication approaches; continuing improvements in the efficiency and reliability of solar cells and modules; and lower PV module and system costs. This talk reviews the rapid progress that has occurred in PV technology from the laboratory to the marketplace, including reviews of the leading technology options, status and issues, and key industry players. New processes for fabricating PV materials and devices, and innovative PV approaches with low-cost potential are elements of an ongoing research program aimed at future advancements in PV cost and performance While major market opportunities continue to exist in the developing countries, where sizable populations are without any electricity, today's manufacturing expansions are fueled by market initiatives for grid-connected PV in residential and commercial buildings. The combinations of increased production capacities, with the attendant cost reductions as a result of economies of scale, are expected to lead to sustainable markets. A key to achieving the ultimate potential of PV is to continue to increase the sunlight-to-electricity conversion efficiencies and translate the laboratory successes to cost-competitive products. Building a robust technology base is essential

Optimal control of a wave energy converter

NARCIS (Netherlands)

Hendrikx, R.W.M.; Leth, J.; Andersen, P; Heemels, W.P.M.H.

2017-01-01

The optimal control strategy for a wave energy converter (WEC) with constraints on the control torque is investigated. The goal is to optimize the total energy delivered to the electricity grid. Using Pontryagin's maximum principle, the solution is found to be singular-bang. Using higher order

Design and Experiment Analysis of a Direct-Drive Wave Energy Converter with a Linear Generator

Directory of Open Access Journals (Sweden)

Jing Zhang

2018-03-01

Full Text Available Coastal waves are an abundant nonpolluting and renewable energy source. A wave energy converter (WEC must be designed for efficient and steady operation in highly energetic ocean environments. A direct-drive wave energy conversion (D-DWEC system with a tubular permanent magnet linear generator (TPMLG on a wind and solar photovoltaic complementary energy generation platform is proposed to improve the conversion efficiency and reduce the complexity and device volume of WECs. The operating principle of D-DWECs is introduced, and detailed analyses of the proposed D-DWEC’s floater system, wave force characteristics, and conversion efficiency conducted using computational fluid dynamics are presented. A TPMLG with an asymmetric slot structure is designed to increase the output electric power, and detailed analyses of the magnetic field distribution, detent force characteristics, and no-load and load performances conducted using finite element analysis are discussed. The TPMLG with an asymmetric slot, which produces the same power as the TPMLG with a symmetric slot, has one fifth detent force of the latter. An experiment system with a prototype of the TPMLG with a symmetric slot is used to test the simulation results. The experiment and analysis results agree well. Therefore, the proposed D-DWEC fulfills the requirements of WEC systems.

Development of a wind converter and investigation of its operational function. Part 1: Technical description of the wind energy converter

Science.gov (United States)

Molly, J. P.; Steinheber, R.

1982-11-01

A 10 kW wind energy converter was developed by using as far possible standard serial production parts. The design criteria and the description of the essential machinery components of the MODA 10 wind energy converter are discussed. For some special load cases the safety calculation of the important components is shown. The blade control system which qualified for small wind energy converters, is explained. Weight and cost of the MODA 10 are considered.

Grid-Forming-Mode Operation of Boost-Power-Stage Converter in PV-Generator-Interfacing Applications

Directory of Open Access Journals (Sweden)

Jukka Viinamäki

2017-07-01

Full Text Available The application of constant power control and inclusion of energy storage in grid-connected photovoltaic (PV energy systems may increase the use of two-stage system structures composed of DC–DC-converter-interfaced PV generator and grid-connected inverter connected in cascade. A typical PV-generator-interfacing DC–DC converter is a boost-power-stage converter. The renewable energy system may operate in three different operation modes—grid-forming, grid-feeding, and grid-supporting modes. In the last two operation modes, the outmost feedback loops are taken from the input terminal of the associated power electronic converters, which usually does not pose stability problems in terms of their input sources. In the grid-forming operation mode, the outmost feedback loops have to be connected to the output terminal of the associated power electronic converters, and hence the input terminal will behave as a negative incremental resistor at low frequencies. This property will limit the operation of the PV interfacing converter in either the constant voltage or constant current region of the PV generator for ensuring stable operation. The boost-power-stage converter can be applied as a voltage or current-fed converter limiting the stable operation region accordingly. The investigations of this paper show explicitly that only the voltage-fed mode would provide feasible dynamic and stability properties as a viable interfacing converter.

Photovoltaic energy in France: 2015, a good year

International Nuclear Information System (INIS)

Courtel, J.; Tuille, F.

2015-01-01

The figures collected for the first semester of 2015 show that the 2014 growth of photovoltaic energy is keeping on. In june 2015 the cumulated installed power reached 6046 MWc. The next challenge is the implementation in january 2016 of a new financial support mechanism based on additional income instead of an EDF's obligation to purchase at fixed tariffs. The additional income is due to be paid with regular periodicity rather than as a whole at the beginning of the project. The amount of the additional income will be calculated as a difference between a maximum target price and the average market price of electricity. This new financial support mechanism shows that the photovoltaic sector is entering a maturity phase. (A.C.)

Efficiency optimization of a photovoltaic water pumping system for irrigation in Ouargla, Algeria

Science.gov (United States)

Louazene, M. L.; Garcia, M. C. Alonso; Korichi, D.

2017-02-01

This work is technical study to contribute to the optimization of pumping systems powered by solar energy (clean) and used in the field of agriculture. To achieve our goals, we studied the techniques that must be entered on a photovoltaic system for maximum energy from solar panels. Our scientific contribution in this research is the realization of an efficient photovoltaic pumping system for irrigation needs. To achieve this and extract maximum power from the PV generator, two axes have been optimized: 1. Increase in the uptake of solar radiation by choice an optimum tilt angle of the solar panels, and 2. it is necessary to add an adaptation device, MPPT controller with a DC-DC converter, between the source and the load.

Can photovoltaic replace nuclear?

International Nuclear Information System (INIS)

2017-01-01

As the French law on energy transition for a green growth predicts that one third of nuclear energy production is to be replaced by renewable energies (wind and solar) by 2025, and while the ADEME proposes a 100 per cent renewable scenario for 2050, this paper proposes a brief analysis of the replacement of nuclear energy by solar photovoltaic energy. It presents and discusses some characteristics of photovoltaic production: production level during a typical day for each month (a noticeable lower production in December), evolution of monthly production during a year, evolution of the rate between nuclear and photovoltaic production. A cost assessment is then proposed for energy storage and for energy production, and a minimum cost of replacement of nuclear by photovoltaic is assessed. The seasonal effect is outlined, as well as the latitude effect. Finally, the authors outline the huge cost of such a replacement, and consider that public support to new photovoltaic installations without an at least daily storage mean should be cancelled

Photovoltaic energy: global market perspectives; Energia fotovoltaica: perspectivas de mercado mundial

Energy Technology Data Exchange (ETDEWEB)

Moreira, Jose G.S.; Fabrizy, Marie P. [Sao Paulo Univ., SP (Brazil). Inst. de Eletrotecnica e Energia

1996-12-31

The global market of the solar photovoltaic energy has been mainly concentrated in the residential sector. However, there is a strong tendency to apply solar photovoltaic panels linked to the utilities power systems. Besides, that is the only case in which an increase in the cells production scale would be justified because it would reduce the production and new technologies research costs 3 figs., 1 tab.; e-mail: gui at iee.usp.br

Comparative Analysis of Resonant Converters for Energy Storage Systems

Directory of Open Access Journals (Sweden)

Vuchev Stoyan

2017-01-01

Full Text Available The following paperwork presents a comparative analysis of multiphase resonant converters for applications in energy storage systems. Models of the examined converters are developed in the software environments of MATLAB and LTspice. Results from the simulation examination of the converters during charging of supercapacitors and rechargeable batteries are presented. These results are compared to results obtained from experimental examination of the converters via a laboratory stand. For the purposes of the experimental examination, a control system is developed on the base of a virtual instrument in LabVIEW. The advantages and disadvantages of the different converters are discussed.

Advanced Receiver/Converter Experiments for Laser Wireless Power Transmission

Science.gov (United States)

Howell, Joe T.; ONeill, Mark; Fork, Richard

2004-01-01

For several years NASA Marshall Space Flight Center, UAH and ENTECH have been working on various aspects of space solar power systems. The current activity was just begun in January 2004 to further develop this new photovoltaic concentrator laser receiver/converter technology. During the next few months, an improved prototype will be designed, fabricated, and thoroughly tested under laser illumination. The final paper will describe the new concept, present its advantages over other laser receiver/converter approaches (including planar photovoltaic arrays), and provide the latest experiment results on prototype hardware (including the effects of laser irradiance level and cell temperature). With NASA's new human exploration plans to first return to the Moon, and then to proceed to Mars, the new photovoltaic concentrator laser receiver/converter technology could prove to be extremely useful in providing power to the landing sites and other phases of the missions. For example, to explore the scientifically interesting and likely resource-rich poles of the Moon (which may contain water) or the poles of Mars (which definitely contain water and carbon dioxide), laser power beaming could represent the simplest means of providing power to these regions, which receive little or no sunlight, making solar arrays useless there. In summary, the authors propose a paper on definition and experimental results of a novel photovoltaic concentrator approach for collecting and converting laser radiation to electrical power. The new advanced photovoltaic concentrator laser receiver/converter offers higher performance, lighter weight, and lower cost than competing concepts, and early experimental results are confirming the expected excellent Performance levels. After the small prototypes are successfully demonstrated, a larger array with even better performance is planned for the next phase experiments and demonstrations. Thereafter, a near-term flight experiment of the new technology

Electro-mechanical energy conversion system having a permanent magnet machine with stator, resonant transfer link and energy converter controls

Science.gov (United States)

Skeist, S. Merrill; Baker, Richard H.

2006-01-10

An electro-mechanical energy conversion system coupled between an energy source and an energy load comprising an energy converter device including a permanent magnet induction machine coupled between the energy source and the energy load to convert the energy from the energy source and to transfer the converted energy to the energy load and an energy transfer multiplexer to control the flow of power or energy through the permanent magnetic induction machine.

Photovoltaic (PV) energy in the Netherlands and Switzerland. A comparison

International Nuclear Information System (INIS)

Van der Loo, F.; Spiessens, P.

1995-01-01

The development of photovoltaic (PV) energy in Switzerland and the Netherlands is compared for a number of aspects. The Swiss have realized more PV capacity. Also the economic conditions to develop PV are better in Switzerland than in the Netherlands. In Switzerland the public support is mobilized for solar energy while in the Netherlands a social basis is created for wind energy. 3 ills., 3 tabs

Analysis of the photovoltaic solar energy capacity of residential rooftops in Andalusia (Spain)

Energy Technology Data Exchange (ETDEWEB)

Ordonez, J.; Jadraque, E.; Alegre, J.; Martinez, G. [Department of Civil Engineering, University of Granada (Spain)

2010-09-15

Fossil fuel energy resources are becoming increasingly scarce. Given the negative environmental impacts (e.g. greenhouse gas emissions) that accompany their use, it is hardly surprising that the development of renewable energies has become a major priority in the world today. Andalusia, with a mean solar radiation of 4.75 kWh/m{sup 2} per day and a surface area of 87,597 km{sup 2}, is the region in Europe with the highest solar energy potential. This research study determined the solar energy potential in Andalusia for grid-connected photovoltaic systems installed on residential rooftops. A methodology was developed for this purpose, which first involved a description of building characteristics, followed by the calculation of the useful roof surface area where photovoltaic arrays could be installed. In the next phase of the study, the mean solar irradiation characteristics were defined as well as the technical parameters of the photovoltaic systems. All of these factors allowed us to estimate the amount of electricity that could be potentially generated per year by solar panels. (author)

Enhanced Reliability of Photovoltaic Systems with Energy Storage and Controls

Energy Technology Data Exchange (ETDEWEB)

Manz, D.; Schelenz, O.; Chandra, R.; Bose, S.; de Rooij, M.; Bebic, J.

2008-02-01

This report summarizes efforts to reconfigure loads during outages to allow individual customers the opportunity to enhance the reliability of their electric service through the management of their loads, photovoltaics, and energy storage devices.

Materials for Photovoltaic Applications

Science.gov (United States)

Dimova-Malinovska, Doriana

Energy priorities are changing nowadays. As mankind will probably have to face energy crisis, factors such as energy independence, energy security, stability of energy supply and the variety of energy sources become much more vital these days. Photovoltaics is exceptional compared to other renewable sources of energy due to its wide opportunity to gain energetic and environmental benefits. An overview of the present state of knowledge of the materials aspects of photovoltaic cells will be given, and new semiconductor materials, including nanomaterials, with potential for application in photovoltaic devices will be identified.

Wave Dragon Wave Energy Converters Used as Coastal Protection

DEFF Research Database (Denmark)

Nørgaard, Jørgen Harck; Andersen, Thomas Lykke; Kofoed, Jens Peter

2011-01-01

This paper deals with wave energy converters used to reduce the wave height along shorelines. For this study the Wave Dragon wave energy converter is chosen. The wave height reduction from a single device has been evaluated from physical model tests in scale 1:51.8 of the 260 x 150 m, 24 kW/m model...... Spain, to evaluate the potential for reducing wave heights close the shore by means of Wave Dragons....

Semiconductor nanowires for photovoltaic and photoelectrochemical energy conversion

Energy Technology Data Exchange (ETDEWEB)

Dasgupta, Neil; Yang, Peidong

2013-01-23

Semiconductor nanowires (NW) possess several beneficial properties for efficient conversion of solar energy into electricity and chemical energy. Due to their efficient absorption of light, short distances for minority carriers to travel, high surface-to-volume ratios, and the availability of scalable synthesis methods, they provide a pathway to address the low cost-to-power requirements for wide-scale adaptation of solar energy conversion technologies. Here we highlight recent progress in our group towards implementation of NW components as photovoltaic and photoelectrochemical energy conversion devices. An emphasis is placed on the unique properties of these one-dimensional (1D) structures, which enable the use of abundant, low-cost materials and improved energy conversion efficiency compared to bulk devices.

Grid-connected wind and photovoltaic system

Science.gov (United States)

Devabakthuni, Sindhuja

The objective of this thesis is to design a grid connected wind and photovoltaic system. A new model of converter control was designed which maintains the voltage of the bus to grid as constant when combined system of solar and wind is connected to AC bus. The model is designed to track maximum power at each point irrespective of changes in irradiance, temperature and wind speed which affects the power supplied to grid. Solar power from the sun is not constant as it is affected by changes in irradiances and temperature. Even the wind power is affected by wind speed. A MPPT controller was designed for both systems. A boost converter is designed which uses the pulses from MPPT controller to boost the output. Wind system consists of wind turbine block from the MATLAB with a pitch angle controller to maintain optimum pitch angle. The output from wind turbine is connected to a permanent magnet synchronous generator. The unregulated DC output from the photovoltaic system is directly given to boost converter. The AC output from the wind system is given to an uncontrolled rectifier to get a unregulated DC output. The unregulated DC output goes to the boost converter. A voltage source inverter was designed which converts the rectified DC output from the boost converter to AC power. The inverter is designed to maintain constant AC bus voltage irrespective of the disturbances in the power supply. Photovoltaic and wind systems are individually designed for 5KW each in MATLAB-Simulink environment. In this thesis, the models were subjected to changes in irradiance, temperature and wind speed and the results were interpreted. The model was successful in tracking maximum at every instant and the AC bus voltage was maintained constant throughout the simulation.

EU Directives, national regulations and incentives for photovoltaic solar energy

International Nuclear Information System (INIS)

Jager-Waldau, A.; Ossenbrink, H.; Scholz, H.; Bloem, H.; Werring, L.

2004-01-01

The European Union long-term strategy for security of energy supply and its commitment to curb climate change led to the adoption of a series of Strategy Papers and EU Directives. In all these, it is clearly stated that climate change is a long-term challenge for the international community and that the commitments made in the Kyoto Protocol can only be a first step. The promotion of renewable energies is a most important element of this process. It regards industry, jobs and foreign trade balance as well, generating benefit to social sustainability. Photovoltaic is a key technology with the potential not only to serve the needs in energy supply of tomorrow in a sustainable way, but already today, it can improve security and stability of electricity services at peak times, due to its decentralized nature. This paper gives an update on the EU and National legislation in place to promote the implementation of photovoltaic. (authors)

Organic photovoltaics

DEFF Research Database (Denmark)

Demming, Anna; Krebs, Frederik C; Chen, Hongzheng

2013-01-01

's supply, even at our increasingly ravenous rate of global energy consumption [1]. But it's not what you have got it's what you do with it. Hence the intense focus on photovoltaic research to find more efficient ways to harness energy from the Sun. Recently much of this research has centred on organic...... solar cells since they offer simple, low-cost, light-weight and large-area flexible photovoltaic structures. This issue with guest editors Frederik C Krebs and Hongzheng Chen focuses on some of the developments at the frontier of organic photovoltaic technology. Improving the power conversion efficiency...... of organic photovoltaic systems, while maintaining the inherent material, economic and fabrication benefits, has absorbed a great deal of research attention in recent years. Here significant progress has been made with reports now of organic photovoltaic devices with efficiencies of around 10%. Yet operating...

Power Converters and Control of Renewable Energy Systems

DEFF Research Database (Denmark)

Blaabjerg, Frede; Teodorescu, Remus; Chen, Zhe

2004-01-01

The global electrical energy consumption is steadily rising and therefore a continuous demand to increase the power generation capacity. A significant percentage of the required capacity increase can be based on renewable energy sources. Wind turbine technology, as the most cost effective renewable...... energy conversion system, will play an important part in our future energy supply. But other sources like microturbines, photovoltaics and fuel cell systems may also be serious contributor to the power supply. Characteristically, power electronics will be an efficient and important interface to the grid...... for the renewables and this paper will first briefly discuss three different alternative/renewable energy sources. Next, various configurations of small and medium power conversion topologies are presented including their control (mainly for PV-systems). Finally wind turbine configuration and their control...

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

Performance Analysis of a Photovoltaic-Thermal Integrated System

Directory of Open Access Journals (Sweden)

Ewa Radziemska

2009-01-01

Full Text Available The present commercial photovoltaic solar cells (PV converts solar energy into electricity with a relatively low efficiency, less than 20%. More than 80% of the absorbed solar energy is dumped to the surroundings again after photovoltaic conversion. Hybrid PV/T systems consist of PV modules coupled with the heat extraction devices. The PV/T collectors generate electric power and heat simultaneously. Stabilizing temperature of photovoltaic modules at low level is higly desirable to obtain efficiency increase. The total efficiency of 60–80% can be achieved with the whole PV/T system provided that the T system is operated near ambient temperature. The value of the low-T heat energy is typically much smaller than the value of the PV electricity. The PV/T systems can exist in many designs, but the most common models are with the use of water or air as a working fuid. Efficiency is the most valuable parameter for the economic analysis. It has substantial meaning in the case of installations with great nominal power, as air-cooled Building Integrated Photovoltaic Systems (BIPV. In this paper the performance analysis of a hybrid PV/T system is presented: an energetic analysis as well as an exergetic analysis. Exergy is always destroyed when a process involves a temperature change. This destruction is proportional to the entropy increase of the system together with its surroundings—the destroyed exergy has been called anergy. Exergy analysis identifies the location, the magnitude, and the sources of thermodynamic inefficiences in a system. This information, which cannot be provided by other means (e.g., an energy analysis, is very useful for the improvement and cost-effictiveness of the system. Calculations were carried out for the tested water-cooled ASE-100-DGL-SM Solarwatt module.

Practical performances of MPC for wave energy converters

DEFF Research Database (Denmark)

Ferri, Francesco; Tetu, Amelie; Hals, J.

2016-01-01

Maximising the efficiency of Wave Energy Converter (WEC) is one of the important tasks toward the exploitation of the wave energy resource. Along with a proper design of the device, an important way to achieve better energy performances is to improve the wave-body interaction by applying an appro...

Performance Evaluation of Wave Energy Converters

DEFF Research Database (Denmark)

Pecher, Arthur

. Guidelines for the development of wave energy converters recommend the use of different prototypes, having different sizes, which have to perform tank tests or sea trials. This implicates the need of different testing environment, which shifts from being controllable to uncontrollable with the development......, with more than 150 concepts currently being developed worldwide. Wave energy conversion concepts can be of many kinds, as the energy in the waves can be absorbed in many different ways. However, each concept is expected to require a thorough development process, involving different phases and prototypes...

Thermal and electrical energy yield analysis of a directly water cooled photovoltaic module

Directory of Open Access Journals (Sweden)

Mtunzi Busiso

2016-01-01

Full Text Available Electrical energy of photovoltaic modules drops by 0.5% for each degree increase in temperature. Direct water cooling of photovoltaic modules was found to give improved electrical and thermal yield. A prototype was put in place to analyse the field data for a period of a year. The results showed an initial high performance ratio and electrical power output. The monthly energy saving efficiency of the directly water cooled module was found to be approximately 61%. The solar utilisation of the naturally cooled photovoltaic module was found to be 8.79% and for the directly water cooled module its solar utilisation was 47.93%. Implementation of such systems on households may reduce the load from the utility company, bring about huge savings on electricity bills and help in reducing carbon emissions.

Large impact of reorganization energy on photovoltaic conversion due to interfacial charge-transfer transitions.

Science.gov (United States)

Fujisawa, Jun-ichi

2015-05-14

Interfacial charge-transfer (ICT) transitions are expected to be a novel charge-separation mechanism for efficient photovoltaic conversion featuring one-step charge separation without energy loss. Photovoltaic conversion due to ICT transitions has been investigated using several TiO2-organic hybrid materials that show organic-to-inorganic ICT transitions in the visible region. In applications of ICT transitions to photovoltaic conversion, there is a significant problem that rapid carrier recombination is caused by organic-inorganic electronic coupling that is necessary for the ICT transitions. In order to solve this problem, in this work, I have theoretically studied light-to-current conversions due to the ICT transitions on the basis of the Marcus theory with density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations. An apparent correlation between the reported incident photon-to-current conversion efficiencies (IPCE) and calculated reorganization energies was clearly found, in which the IPCE increases with decreasing the reorganization energy consistent with the Marcus theory in the inverted region. This activation-energy dependence was systematically explained by the equation formulated by the Marcus theory based on a simple excited-state kinetic scheme. This result indicates that the reduction of the reorganization energy can suppress the carrier recombination and enhance the IPCE. The reorganization energy is predominantly governed by the structural change in the chemical-adsorption moiety between the ground and ICT excited states. This work provides crucial knowledge for efficient photovoltaic conversion due to ICT transitions.

Joint energy demand and thermal comfort optimization in photovoltaic-equipped interconnected microgrids

International Nuclear Information System (INIS)

Baldi, Simone; Karagevrekis, Athanasios; Michailidis, Iakovos T.; Kosmatopoulos, Elias B.

2015-01-01

Highlights: • Energy efficient operation of photovoltaic-equipped interconnected microgrids. • Optimized energy demand for a block of heterogeneous buildings with different sizes. • Multiobjective optimization: matching demand and supply taking into account thermal comfort. • Intelligent control mechanism for heating, ventilating, and air conditioning units. • Optimization of energy consumption and thermal comfort at the aggregate microgrid level. - Abstract: Electrical smart microgrids equipped with small-scale renewable-energy generation systems are emerging progressively as an alternative or an enhancement to the central electrical grid: due to the intermittent nature of the renewable energy sources, appropriate algorithms are required to integrate these two typologies of grids and, in particular, to perform efficiently dynamic energy demand and distributed generation management, while guaranteeing satisfactory thermal comfort for the occupants. This paper presents a novel control algorithm for joint energy demand and thermal comfort optimization in photovoltaic-equipped interconnected microgrids. Energy demand shaping is achieved via an intelligent control mechanism for heating, ventilating, and air conditioning units. The intelligent control mechanism takes into account the available solar energy, the building dynamics and the thermal comfort of the buildings’ occupants. The control design is accomplished in a simulation-based fashion using an energy simulation model, developed in EnergyPlus, of an interconnected microgrid. Rather than focusing only on how each building behaves individually, the optimization algorithm employs a central controller that allows interaction among the buildings of the microgrid. The control objective is to optimize the aggregate microgrid performance. Simulation results demonstrate that the optimization algorithm efficiently integrates the microgrid with the photovoltaic system that provides free electric energy: in

Energy-saving operation of a converter-fed synchronous machine

Energy Technology Data Exchange (ETDEWEB)

Schmidt, I.; Veszpremi, K. [Technical University of Budapest, Department of Electrical Machines and Drives, Budapest (Hungary)

1997-12-31

In the Converter-Fed Synchronous Machine (CFSM) there is no need for forced commutation the CL and CF converters operate with line commutation, the CM is commutated by the machine voltages. This drive is applied mainly for large power and high speed controlled drives. Considering the large power, the investigation of energy-saving operation is important. As in the DC and the induction motor drives the energy-saving operation is implemented by flux control. (orig.) 6 refs.

International Energy Agency Ocean Energy Systems Task 10 Wave Energy Converter Modeling Verification and Validation

DEFF Research Database (Denmark)

Wendt, Fabian F.; Yu, Yi-Hsiang; Nielsen, Kim

2017-01-01

This is the first joint reference paper for the Ocean Energy Systems (OES) Task 10 Wave Energy Converter modeling verification and validation group. The group is established under the OES Energy Technology Network program under the International Energy Agency. OES was founded in 2001 and Task 10 ...

Development of the Wave Energy Converter -Wave Dragon

DEFF Research Database (Denmark)

Kofoed, Jens Peter; Frigaard, Peter; Sørensen, Hans Christian

2000-01-01

2Over the years wave energy has gradually been brought into focus, as it has become clear that the fossil energy resources are limited, and cause large environmental problems, e.g. CO2 pollution. On this background a number of different wave energy converters have been proposed. In Denmark the go...

Photovoltaic Energy Program Contract Summary; Fiscal Year 1998

Energy Technology Data Exchange (ETDEWEB)

Surek, T.

1999-02-16

This document provides individual summaries of some 200 photovoltaics research projects performed in house and by subcontractors to Department of Energy national laboratories and field offices, including the National Renewable Energy Laboratory, Sandia National Laboratories, Golden Field Office, Brookhaven National Laboratory, Albuquerque Field Office, and Boston Support Office. The document is divided into the following sections: research and development, technology development, and systems engineering and applications. Three indexes are included: performing organizations by name, performing organizations by state, and performing organizations by technology area.

Photovoltaic sources modeling and emulation

CERN Document Server

Piazza, Maria Carmela Di

2012-01-01

This book offers an extensive introduction to the modeling of photovoltaic generators and their emulation by means of power electronic converters will aid in understanding and improving design and setup of new PV plants.

Matrix converter applied to energy saving for street lighting systems

OpenAIRE

Román Lumbreras, Manuel; Velasco Quesada, Guillermo; Conesa Roca, Alfons

2010-01-01

This work presents a three-phase AC-AC converter, with independent phase control, based on matrix-converter structure. This converter is applied to electrical energy saving on the public lighting systems by means of regulation and control of the voltage applied to the lamps. The developed converter represents a technological improvement with respect to the traditional systems based on an autotransformer: it reduces system cost and volume, and increases lamps lifetime.

Aiding Design of Wave Energy Converters via Computational Simulations

Science.gov (United States)

Jebeli Aqdam, Hejar; Ahmadi, Babak; Raessi, Mehdi; Tootkaboni, Mazdak

2015-11-01

With the increasing interest in renewable energy sources, wave energy converters will continue to gain attention as a viable alternative to current electricity production methods. It is therefore crucial to develop computational tools for the design and analysis of wave energy converters. A successful design requires balance between the design performance and cost. Here an analytical solution is used for the approximate analysis of interactions between a flap-type wave energy converter (WEC) and waves. The method is verified using other flow solvers and experimental test cases. Then the model is used in conjunction with a powerful heuristic optimization engine, Charged System Search (CSS) to explore the WEC design space. CSS is inspired by charged particles behavior. It searches the design space by considering candidate answers as charged particles and moving them based on the Coulomb's laws of electrostatics and Newton's laws of motion to find the global optimum. Finally the impacts of changes in different design parameters on the power takeout of the superior WEC designs are investigated. National Science Foundation, CBET-1236462.

Use of the photovoltaic cells as fission fragment sensors and study of a preamplifier adapted to the cells

International Nuclear Information System (INIS)

Jin Yimeng.

1989-04-01

In the detection of heavy ions and fission fragments, the photovoltaic cells can take the place of traditional silicon surface barrier detectors, if we need a great number of detectors as in the case of 4π multidetector, and do not expect excellent energy and time resolutions at the same time. Made for the purpose of converting the solar energy to the electrical energy, the photovoltaic cells have the similar structure as silicon surface barrier detectors, except for their much thinner pn junctions and, as a result much larger junction capacities, which is a major disadvantage for photovoltaic cells as fission fragment detectors. In order to get an acceptable energy resolution and a time resolution as good as possible, it is necessary to design a preamplifier specially adapted to cells, which plays a very important role in the utilization of photovoltaic cells as detectors. In the present work we analyze the electrical signal from a cell when hit by a fission fragment, and propose a new type cell oriented preamplifier of voltage, with which we can use a cell up to 10 cm 2 , and obtain a time resolution better than 16 ns [fr

Development of the Wave Energy Converter

DEFF Research Database (Denmark)

Kofoed, Jens Peter; Frigaard, Peter; Sørensen, Hans Christian

2000-01-01

The development of the wave energy converter Wave Dragon (WD) is presented. The WD is based on the overtopping principle. Initially a description of the WD is given. Then the development over time in terms of the various research and development projects working with the concept is described. Thi...

The role of Photovoltaics towards 100% Renewable energy systems

DEFF Research Database (Denmark)

Mathiesen, Brian Vad; David, Andrei; Petersen, Silas

builds on a literature review of the global and Danish trends in capacity, costs and types of support schemes, but also develops a GIS and energy system analysis supported by a set of economic calculations to inquire on the recommended pathway for the future investments in photovoltaics in Denmark...

Proceedings of the 12th Space Photovoltaic Research and Technology Conference (SPRAT 12)

Science.gov (United States)

1993-01-01

The Twelfth Space Photovoltaic Research and Technology conference was held at the NASA Lewis Research Center from 20 to 22 Oct. 1992. The papers and workshops presented in this volume report substantial progress in a variety of areas in space photovoltaics. Topics covered include: high efficiency GaAs and InP solar cells, GaAs/Ge cells as commercial items, flexible amorphous and thin film solar cells (in the early stages of pilot production), high efficiency multiple bandgap cells, laser power converters, solar cell and array technology, heteroepitaxial cells, betavoltaic energy conversion, and space radiation effects in InP cells. Space flight data on a variety of cells were also presented.

Characteristics Study of Photovoltaic Thermal System with Emphasis on Energy Efficiency

Directory of Open Access Journals (Sweden)

Yong Chuah Yee

2018-01-01

Full Text Available Solar energy is typically collected through photovoltaic (PV to generate electricity or through thermal collectors as heat energy, they are generally utilised separately. This project is done with the purpose of integrating the two systems to improve the energy efficiency. The idea of this photovoltaic-thermal (PVT setup design is to simultaneously cool the PV panel so it can operate at a lower temperature thus higher electrical efficiency and also store the thermal energy. The experimental data shows that the PVT setup increased the electrical efficiency of the standard PV setup from 1.64% to 2.15%. The integration of the thermal collector also allowed 37.25% of solar energy to be stored as thermal energy. The standard PV setup harnessed only 1.64% of the solar energy, whereas the PVT setup achieved 39.4%. Different flowrates were tested to determine its effects on the PVT setup’s electrical and thermal efficiency. The various flowrate does not significantly impact the electrical efficiency since it did not significantly impact the cooling of the panel. The various flowrates resulted in fluctuating thermal efficiencies, the relation between the two is inconclusive in this project.

Performance of arrays of direct-driven wave energy converters under optimal power take-off damping

Directory of Open Access Journals (Sweden)

Liguo Wang

2016-08-01

Full Text Available It is well known that the total power converted by a wave energy farm is influenced by the hydrodynamic interactions between wave energy converters, especially when they are close to each other. Therefore, to improve the performance of a wave energy farm, the hydrodynamic interaction between converters must be considered, which can be influenced by the power take-off damping of individual converters. In this paper, the performance of arrays of wave energy converters under optimal hydrodynamic interaction and power take-off damping is investigated. This is achieved by coordinating the power take-off damping of individual converters, resulting in optimal hydrodynamic interaction as well as higher production of time-averaged power converted by the farm. Physical constraints on motion amplitudes are considered in the solution, which is required for the practical implementation of wave energy converters. Results indicate that the natural frequency of a wave energy converter under optimal damping will not vary with sea states, but the production performance of a wave energy farm can be improved significantly while satisfying the motion constraints.

Performance of arrays of direct-driven wave energy converters under optimal power take-off damping

Science.gov (United States)

Wang, Liguo; Engström, Jens; Leijon, Mats; Isberg, Jan

2016-08-01

It is well known that the total power converted by a wave energy farm is influenced by the hydrodynamic interactions between wave energy converters, especially when they are close to each other. Therefore, to improve the performance of a wave energy farm, the hydrodynamic interaction between converters must be considered, which can be influenced by the power take-off damping of individual converters. In this paper, the performance of arrays of wave energy converters under optimal hydrodynamic interaction and power take-off damping is investigated. This is achieved by coordinating the power take-off damping of individual converters, resulting in optimal hydrodynamic interaction as well as higher production of time-averaged power converted by the farm. Physical constraints on motion amplitudes are considered in the solution, which is required for the practical implementation of wave energy converters. Results indicate that the natural frequency of a wave energy converter under optimal damping will not vary with sea states, but the production performance of a wave energy farm can be improved significantly while satisfying the motion constraints.

Electricity from photovoltaic solar cells. Flat-Plate Solar Array Project of the US Department of Energy's National Photovoltaics Program: 10 years of progress

Science.gov (United States)

Christensen, Elmer

1985-01-01

The objectives were to develop the flat-plate photovoltaic (PV) array technologies required for large-scale terrestrial use late in the 1980s and in the 1990s; advance crystalline silicon PV technologies; develop the technologies required to convert thin-film PV research results into viable module and array technology; and to stimulate transfer of knowledge of advanced PV materials, solar cells, modules, and arrays to the PV community. Progress reached on attaining these goals, along with future recommendations are discussed.

Thin Film Photovoltaics

Energy Technology Data Exchange (ETDEWEB)

Zweibel, K.

1998-11-19

The motivation to develop thin film technologies dates back to the inception of photovoltaics. It is an idea based on achieving truly low-cost photovoltaics appropriate for mass production and energy significant markets. The key to the idea is the use of pennies worth of active materials. Since sunlight carries relatively little energy in comparison with combustion-based energy sources, photovoltaic (PV) modules must be cheap to produce energy that can be competitive. Thin films are presumed to be the answer to that low-cost requirement. But how cheap do they have to be? The following is an oversimplified analysis that allows some insight into this question.

Modeling Of Components Of A Photovoltaic System With Voltage Inverter For Connection To The Electrical Grid

International Nuclear Information System (INIS)

Ferreira, Andreza C.; Blasques, Luis C. M.; Galhardo, Marcos A. B.; Pinho, João T.

2017-01-01

This paper describes the modeling of the electrical equipment and control mechanisms used in the power conditioning system of a grid-connected photovoltaic system (GCPVS), such as the photovoltaic generator, the DC/DC converter, the voltage inverter with PWM control, its output filter, as well as the converter controls and their functionalities, and the interconnection of the system with the distribution grid and load. In addition to the modeling of the grid-tie inverter, the main equipment of the power conditioning system, this paper describes the synchronization form of the photovoltaic (PV) generation with the electricity distribution grid, considering the power injection control method, the maximum power point tracking technique for maximizing the energy supplied by the photovoltaic generator, and the complete topology of the proposed PV system. The main objective is to provide a computational model capable of simulating the behavior of the GCPVS elements, varying the climatic conditions and the power demand on the AC side, presenting consistent results for different operating conditions, such as variations of climatic parameters (solar irradiance, wind speed, and ambient temperature) and load. In these cases, it is possible to evaluate the behavior of the system, sometimes supplying both the active and reactive power of the load, according to the need. (author)

Optimal Sizing of Decentralized Photovoltaic Generation and Energy Storage Units for Malaysia Residential Household Using Iterative Method

Directory of Open Access Journals (Sweden)

Rahman Hasimah Abdul

2016-01-01

Full Text Available World’s fuel sources are decreasing, and global warming phenomena cause the necessity of urgent search for alternative energy sources. Photovoltaic generating system has a high potential, since it is clean, environmental friendly and secure energy sources. This paper presents an optimal sizing of decentralized photovoltaic system and electrical energy storage for a residential household using iterative method. The cost of energy, payback period, degree of autonomy and degree of own-consumption are defined as optimization parameters. A case study is conducted by employing Kuala Lumpur meteorological data, typical load profile from rural area in Malaysia, decentralized photovoltaic generation unit and electrical storage and it is analyzed in hourly basis. An iterative method is used with photovoltaic array variable from 0.1kW to 4.0kW and storage system variable from 50Ah to 400Ah was performed to determine the optimal design for the proposed system.

Isolated high-efficiency DC/DC converter for photovoltaic applications

NARCIS (Netherlands)

Vermulst, B.J.D.; Wijnands, C.G.E.; Duarte, J.L.

2012-01-01

While an increasing number of photovoltaic (PV) systems is installed, those systems typically use central inverters. In practical cases, output-power differences between PV modules will cause these central-inverter-based systems not to achieve Maximum Power Point (MPP) for each PV module.

Hydraulic Response of the Wave Energy Converter Wave Dragon in Nissum Bredning

DEFF Research Database (Denmark)

Kofoed, Jens Peter; Frigaard, Peter

This report deals with the hydraulic performance of the wave energy converter Wave Dragon, Nissum Bredning prototype.......This report deals with the hydraulic performance of the wave energy converter Wave Dragon, Nissum Bredning prototype....

Enhancing solar cell efficiency: the search for luminescent materials as spectral converters.

Science.gov (United States)

Huang, Xiaoyong; Han, Sanyang; Huang, Wei; Liu, Xiaogang

2013-01-07

Photovoltaic (PV) technologies for solar energy conversion represent promising routes to green and renewable energy generation. Despite relevant PV technologies being available for more than half a century, the production of solar energy remains costly, largely owing to low power conversion efficiencies of solar cells. The main difficulty in improving the efficiency of PV energy conversion lies in the spectral mismatch between the energy distribution of photons in the incident solar spectrum and the bandgap of a semiconductor material. In recent years, luminescent materials, which are capable of converting a broad spectrum of light into photons of a particular wavelength, have been synthesized and used to minimize the losses in the solar-cell-based energy conversion process. In this review, we will survey recent progress in the development of spectral converters, with a particular emphasis on lanthanide-based upconversion, quantum-cutting and down-shifting materials, for PV applications. In addition, we will also present technical challenges that arise in developing cost-effective high-performance solar cells based on these luminescent materials.

Electric properties of organic and mineral electronic components, design and modelling of a photovoltaic chain for a better exploitation of the solar energy; Proprietes electriques des composants electroniques mineraux et organiques, conception et modelisation d'une chaine photovoltaique pour une meilleure exploitation de l'energie solaire

Energy Technology Data Exchange (ETDEWEB)

Aziz, A

2006-11-15

The research carried out in this thesis relates to the mineral, organic electronic components and the photovoltaic systems. Concerning the mineral semiconductors, we modelled the conduction properties of the structures metal/oxide/semiconductor (MOS) strongly integrated in absence and in the presence of charges. We proposed a methodology allowing characterizing the ageing of structures MOS under injection of the Fowler Nordheim (FN) current type. Then, we studied the Schottky diodes in polymers of type metal/polymer/metal. We concluded that: The mechanism of the charges transfer, through the interface metal/polymer, is allotted to the thermo-ionic effect and could be affected by the lowering of the potential barrier to the interface metal/polymer. In the area of photovoltaic energy, we conceived and modelled a photovoltaic system of average power (100 W). We showed that the adaptation of the generator to the load allows a better exploitation of solar energy. This is carried out by the means of the converters controlled by an of type MPPT control provided with a detection circuit of dysfunction and restarting of the system. (author)

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...... illumination profiles. The comparison is performed based on dynamic characterization and evaluation of the devices energy loss at different current levels....

Modeling Photovoltaic Power

OpenAIRE

Mavromatakis, F.; Franghiadakis, Y.; Vignola, F.

2016-01-01

A robust and reliable model describing the power produced by a photovoltaic system is needed in order to be able to detect module failures, inverter malfunction, shadowing effects and other factors that may result to energy losses. In addition, a reliable model enables an investor to perform accurate estimates of the system energy production, payback times etc. The model utilizes the global irradiance reaching the plane of the photovoltaic modules since in almost all Photovoltaic (PV) facilit...

Photovoltaics fundamentals, technology and practice

CERN Document Server

Mertens, Konrad

2013-01-01

Concise introduction to the basic principles of solar energy, photovoltaic systems, photovoltaic cells, photovoltaic measurement techniques, and grid connected systems, overviewing the potential of photovoltaic electricity for students and engineers new to the topic After a brief introduction to the topic of photovoltaics' history and the most important facts, Chapter 1 presents the subject of radiation, covering properties of solar radiation, radiation offer, and world energy consumption. Chapter 2 looks at the fundamentals of semiconductor physics. It discusses the build-up of semiconducto

Optimum technoeconomic energy autonomous photovoltaic solution for remote consumers throughout Greece

International Nuclear Information System (INIS)

Kaldellis, J.K.

2004-01-01

Autonomous photovoltaic systems have turned into one of the most promising ways to handle the electrification requirements of numerous isolated consumers worldwide. Such an autonomous system comprises a number of photovoltaic panels, properly connected, and a battery storage device, along with the corresponding electronic equipment. Considering the high solar potential of most Greek territories, an integrated study is conducted based on long term solar potential experimental measurements in order to determine the optimum configuration of a stand alone photovoltaic system at representative locations all over Greece. The proposed solution 'guarantees' zero load rejections for all the areas and time periods examined. For this purpose, a fast and reliable numerical code 'PHOTOV-III' has been used. The algorithm provides analytical results concerning the energy autonomy and the operational status of the autonomous system components. Besides, the optimum panel tilt angle, minimizing the first installation cost of a small photovoltaic system, is predicted. Finally, by introducing available financial aspects, it is possible to determine the optimum system dimensions on a minimum first installation cost basis. According to the results obtained, an autonomous photovoltaic system can definitely contribute to solution of the urgent electrification problem of remote consumers spread throughout Greece, also improving their life quality level

Seawater pumping as an electricity storage solution for photovoltaic energy systems

International Nuclear Information System (INIS)

Manfrida, Giampaolo; Secchi, Riccardo

2014-01-01

The stochastic nature of several renewable energy sources has raised the problem of designing and building storage facilities, which can help the electricity grid to sustain larger and larger contribution of renewable energy. Seawater pumped electricity storage is proposed as a good option for PV (Photovoltaic) or solar thermal power plants, located in suitable places close to the coast line. Solar radiation has a natural daily cycle, and storage reservoirs of limited capacity can substantially reduce the load to the electricity grid. Different modes of pump operation (fixed or variable speed) are considered, the preliminary sizing of the PV field and seawater reservoir is performed, and the results are comparatively assessed over a year-long simulated operation. The results show that PV pumped storage, even if not profitable in the present situation of the renewable energy Italian electricity market, is effective in decreasing the load on the transmission grid, and would possibly be attractive in the future, also in the light of developing off-grid applications. - Highlights: • A grid-connected seawater pumping system using photovoltaic power is proposed and its performance analyzed. • Year-round simulations are run with different sizes of photovoltaic field and reservoir. • An analysis is run about the profitability of the storage system, examining performance indexes and the cost of plant. • The system proposed appears near to attract the interest of the market

Fuzzy Controller Design Using FPGA for Photovoltaic Maximum Power Point Tracking

OpenAIRE

Basil M Hamed; Mohammed S. El-Moghany

2012-01-01

The cell has optimum operating point to be able to get maximum power. To obtain Maximum Power from photovoltaic array, photovoltaic power system usually requires Maximum Power Point Tracking (MPPT) controller. This paper provides a small power photovoltaic control system based on fuzzy control with FPGA technology design and implementation for MPPT. The system composed of photovoltaic module, buck converter and the fuzzy logic controller implemented on FPGA for controlling on/off time of MOSF...

Comparative Study of Two New Configurations of Solar Photovoltaic Thermal Collectors

OpenAIRE

K. Touafek; A. Khelifa; E. H. Khettaf; A. Embarek

2013-01-01

Hybrid photovoltaic thermal (PV/T) solar system comprises a solar collector which is disposed on photovoltaic solar cells. The disadvantage of a conventional photovoltaic cell is that its performance decreases as the temperature increases. Indeed, part of the solar radiation is converted into electricity and is dissipated as heat, increasing the temperature of the photovoltaic cell with respect to the ambient temperature. The objective of this work is to study experimentally and implement a h...

Miniature photovoltaic energy system for lighting

International Nuclear Information System (INIS)

Awais, M.

1999-01-01

In this project a miniature photovoltaic energy system has been designed and developed, that may be used in remote areas and villages for lighting purposes. System sizing is the important part of the project because it affects the cost of the system. Therefore, first of all system sizing has been done. For conversion of dc voltage of the battery into ac voltage, an inverter has been designed. To charge the battery when the sun is not shining, a standby system has been developed using a bicycle and dynamo. To indicate the battery's state of charge and discharge, a battery monitoring circuit has also been developed. Similarly, to protect the battery from over discharging, a battery protection circuit has been designed. In order to measure how much energy is going from standby system to the battery, an efficient dc electronic energy meter has been designed and developed. The working of the overall system has been tested and found to give good performance. (author)

A hybrid method for forecasting the energy output of photovoltaic systems

International Nuclear Information System (INIS)

Ramsami, Pamela; Oree, Vishwamitra

2015-01-01

Highlights: • We propose a novel hybrid technique for predicting the daily PV energy output. • Multiple linear regression, FFNN and GRNN artificial neural networks are used. • Stepwise regression is used to select the most relevant meteorological parameters. • SR-FFNN reduces the average dispersion and overall bias in prediction errors. • Accuracy metrics of hybrid models are better than those of single-stage models. - Abstract: The intermittent nature of solar energy poses many challenges to renewable energy system operators in terms of operational planning and scheduling. Predicting the output of photovoltaic systems is therefore essential for managing the operation and assessing the economic performance of power systems. This paper presents a new technique for forecasting the 24-h ahead stochastic energy output of photovoltaic systems based on the daily weather forecasts. A comparison of the performances of the hybrid technique with conventional linear regression and artificial neural network models has also been reported. Initially, three single-stage models were designed, namely the generalized regression neural network, feedforward neural network and multiple linear regression. Subsequently, a hybrid-modeling approach was adopted by applying stepwise regression to select input variables of greater importance. These variables were then fed to the single-stage models resulting in three hybrid models. They were then validated by comparing the forecasts of the models with measured dataset from an operational photovoltaic system. The accuracy of the each model was evaluated based on the correlation coefficient, mean absolute error, mean bias error and root mean square error values. Simulation results revealed that the hybrid models perform better than their corresponding single-stage models. Stepwise regression-feedforward neural network hybrid model outperformed the other models with root mean square error, mean absolute error, mean bias error and

Photovoltaic industry in France in 2013. French version of the report written for the photovoltaic program of the International Energy Agency. Final report

International Nuclear Information System (INIS)

Durand, Yvonnick

2014-06-01

This document is the French National Survey Report on photovoltaic energy for the year 2013. This report provides a comprehensive review of photovoltaic activities in France in 2013. It describes the current state of the PV market, including French authorities' support measures and economic aspects. It gives an account of PV industry with key manufacturers and operators as well as R and D programmes. The data contained in the report concern the year 2013. The main sources of information used for the report are the following: data produced by the French Observation and statistics office (SOeS, Service de l'observation et des statistiques), ADEME's reports and studies, reports and studies produced by the Syndicat des energies renouvelables (SER) and by ENERPLAN union, publications Systemes solaires, reports by Observatoire des energies renouvelables (Observer), Plein Soleil magazine, web sites (institutional, photovoltaic.info, L'echo du solaire, etc.), data from equipment suppliers, company publications and press releases, corporate strategy flyers and contacts with professionals in the sector

Operation and maintenance strategies for wave energy converters

DEFF Research Database (Denmark)

Ambühl, Simon; Marquis, Laurent; Kofoed, Jens Peter

2015-01-01

costs including costs due to lost electricity production are minimized. The risk-based approach is compared with an approach where only boats are used and another approach where the target is to minimize the downtime of the device. This article presents a dynamic approach for total operation......Inspection and maintenance costs are a significant contributor to the cost of energy for wave energy converters. There are different operation and maintenance strategies for wave energy converters. Maintenance can be performed after failure (corrective) or before a breakdown (preventive) occurs....... Furthermore, a helicopter and boats can be used to transport equipment and personnel to the device, or the whole device can be towed to a harbour for operation and maintenance actions. This article describes, among others, a risk-based inspection and maintenance planning approach where the overall repair...

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.

An Appraisal of the DEXA Wave Energy Converter

DEFF Research Database (Denmark)

Pecher, Arthur; Kofoed, Jens Peter

This report has been requested by VækstFonden and aims at giving an overview of the experimental tests and a general appraisal of the DEXA wave energy converter (WEC). The reported results and findings were obtained during previously performed experimental tests by the Wave Energy Research Group...

Maximum wind energy extraction strategies using power electronic converters

Science.gov (United States)

Wang, Quincy Qing

2003-10-01

This thesis focuses on maximum wind energy extraction strategies for achieving the highest energy output of variable speed wind turbine power generation systems. Power electronic converters and controls provide the basic platform to accomplish the research of this thesis in both hardware and software aspects. In order to send wind energy to a utility grid, a variable speed wind turbine requires a power electronic converter to convert a variable voltage variable frequency source into a fixed voltage fixed frequency supply. Generic single-phase and three-phase converter topologies, converter control methods for wind power generation, as well as the developed direct drive generator, are introduced in the thesis for establishing variable-speed wind energy conversion systems. Variable speed wind power generation system modeling and simulation are essential methods both for understanding the system behavior and for developing advanced system control strategies. Wind generation system components, including wind turbine, 1-phase IGBT inverter, 3-phase IGBT inverter, synchronous generator, and rectifier, are modeled in this thesis using MATLAB/SIMULINK. The simulation results have been verified by a commercial simulation software package, PSIM, and confirmed by field test results. Since the dynamic time constants for these individual models are much different, a creative approach has also been developed in this thesis to combine these models for entire wind power generation system simulation. An advanced maximum wind energy extraction strategy relies not only on proper system hardware design, but also on sophisticated software control algorithms. Based on literature review and computer simulation on wind turbine control algorithms, an intelligent maximum wind energy extraction control algorithm is proposed in this thesis. This algorithm has a unique on-line adaptation and optimization capability, which is able to achieve maximum wind energy conversion efficiency through

Capacity analysis of amortization of energy and environmental liabilities photovoltaic panels

International Nuclear Information System (INIS)

Tiago Filho, Geraldo Lucio; Adriano Rosa, Carlos

2011-01-01

The claim that the use of solar energy through photovoltaic (PV) panels is a clean energy source is based, in most cases, considering only the generation of electricity by the group after manufacture and installation. Without considering the process of manufacture, neither more nor less CO2 emissions are produced, and other degradation environment, which vary according to the country's energy matrix in which these activities develop. This article uses analysis tools to study the impacts of life cycle environment that have passed since the exploitation of mineral deposits used in the manufacture of major components for the manufacture of the panel. In this study adds to quantify the emissions of various gases, emitted in the manufacturing process of photovoltaic modules, expressed in equivalent tons of CO2, resulting from the process and depending on the country in which the panel is manufactured and the depreciation of environmental liabilities, to allow life determination (author)

Full wave dc-to-dc converter using energy storage transformers

Science.gov (United States)

Moore, E. T.; Wilson, T. G.

1969-01-01

Full wave dc-to-dc converter, for an ion thrustor, uses energy storage transformers to provide a method of dc-to-dc conversion and regulation. The converter has a high degree of physical simplicity, is lightweight and has high efficiency.

Photovoltaics as a worldwide energy option: A case study in development strategy

International Nuclear Information System (INIS)

Jones, G.; Pate, R.; Hill, R.

1991-01-01

Renewable energy technologies, such as solar thermal electric, photovoltaics (PV), and wind energy have made significant gains in cost and performance in the past decades. As a result, there have been high expectations on the part of the public for these sources to play a major role in future energy supply, especially as environmental concerns about conventional sources increase. Despite these past gains and high expectations, the global potential of renewable energy technologies still remains largely untapped, principally because of issues of industrialization and user acceptance. There is increasing recognition that government energy programs must incorporate a broader strategy than the traditional basic research role if they are to address these issues. Essential elements of this strategy are affordable technology, a healthy industry, sustained market growth, user acceptance, and equitable policy and financial environments. The US Department of Energy (DOE) programs in solar electric conversion have already started the development of the required broader-based effort. This paper presents the status of that work, utilizing the US National Photovoltaic Program as a case study

Performance Evaluation of Wave Energy Converters

DEFF Research Database (Denmark)

Pecher, Arthur

Ocean waves provide a sustainable, power-dense, predictable and widely available source of energy that could provide about 10 % of worlds energy needs. While research into waveenergy has been undertaken for decades, a significant increase in related activities has been seen in the recent years......, with more than 150 concepts currently being developed worldwide. Wave energy conversion concepts can be of many kinds, as the energy in the waves can be absorbed in many different ways. However, each concept is expected to require a thorough development process, involving different phases and prototypes....... Guidelines for the development of wave energy converters recommend the use of different prototypes, having different sizes, which have to perform tank tests or sea trials. Thisimplicates the need of different testing environment, which shifts from being controllable to uncontrollable with the development...

From low cost to high tech: possible margins of technical progress in photovoltaic;Du low cost a la high-tech: des marges de progres techniques possibles pour le photovoltaique

Energy Technology Data Exchange (ETDEWEB)

Guillemoles, J.F. [CNRS, directeur adjoint a la Recherche de l' Institut de R and D de l' Energie Photovoltaique (IRDEP), Unite Mixte de Recherche CNRS-EDF-Paristech, 78 - Chatou (France)

2009-11-15

Photovoltaic is developing in response to 3 requirements: conservation of the environment, security in energy, and economic growth. Given this, the terawatt (TW) scale should be used to measure the magnitude of energy needs. Can solar, in particular photovoltaic, power meet these needs? This has nothing to do with the availability of solar energy - in a single hour, the sun sends to the earth as much energy as the electricity consumed by all of humanity during an entire year. Instead, it raises questions about the industrial deployment and, eventually, the availability of raw materials and land. The sustainable development of photovoltaic power implies wisely using resources (raw materials, energy and capital) and improving the efficiency not only of the process for transforming resources into photovoltaic units but also of the photovoltaic units themselves for converting light into electricity. It is worth noting that the predictable change of scale in the photovoltaic industry will have implications for this industry's deployment on a large scale. This deployment depends on: the availability of technology, know-how, capital and raw materials; the cost of investments; the speed of implementation; and the rhythm of production of cells. (author)

High Efficiency Non-isolated Three Port DC-DC Converter for PV-Battery Systems

OpenAIRE

Tomas Manez, Kevin; Anthon, Alexander; Zhang, Zhe; Ouyang, Ziwei; Franke, Toke

2016-01-01

This paper presents a nonisolated Three Port Converter (TPC) with a unidirectional port for photovoltaic (PV) panels and a bidirectional port for energy storage. With the proposed topology single power conversion is performed between each port, so high efficiencies are obtained. A theoretical analysis is carried out to analyze all operating modes and design considerations with the main equations are given. A 4kW laboratory prototype is developed and tested under all operatingconditions. Resul...

On Mooring Solutions for Large Wave Energy Converters

DEFF Research Database (Denmark)

Thomsen, Jonas Bjerg; Kofoed, Jens Peter; Ferri, Francesco

2017-01-01

The present paper describes the work carried out in the project ’Mooring Solutions for Large Wave Energy Converters’, which is a Danish research project carried out in a period of three years from September 2014, with the aim of reducing cost of the moorings for four wave energy converters...

Solar energy conversion

Energy Technology Data Exchange (ETDEWEB)

Kistler, J.

1981-08-05

The photovoltaic generator is the central part of all solar systems. Flat solar cells embedded in glass are preferred which can also convert diffuse solar radiation. Hybrid modules generate electrical and thermal energy simultaneously. With decreasing generator cost, the cost of energy storage becomes critical. Development activities are mostly directed on the development of stationary lead accumulator batteries and the electronic charging and protective systems. The block diagram of the current converter is presented, and applications of solar systems in domestic heating engineering, transportation technology, communications, and hydrological engineering. Solar villages are recommended which, established in bilateral cooperation with Third World authorities, may demonstrate the advantages of solar energy in heat and electric power generation.

Energy metrics analysis of hybrid - photovoltaic (PV) modules

Energy Technology Data Exchange (ETDEWEB)

Tiwari, Arvind [Department of Electronics and Communication, Krishna Institute of Engineering and Technology, 13 k.m. stone, Ghaziabad - Meerut Road, Ghaziabad 201 206, UP (India); Barnwal, P.; Sandhu, G.S.; Sodha, M.S. [Centre for Energy Studies, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110 016 (India)

2009-12-15

In this paper, energy metrics (energy pay back time, electricity production factor and life cycle conversion efficiency) of hybrid photovoltaic (PV) modules have been analyzed and presented for the composite climate of New Delhi, India. For this purpose, it is necessary to calculate (1) the energy consumption in making different components of the PV modules and (2) the annual energy (electrical and thermal) available from the hybrid-PV modules. A set of mathematical relations have been reformulated for computation of the energy metrics. The manufacturing energy, material production energy, energy use and distribution energy of the system have been taken into account, to determine the embodied energy for the hybrid-PV modules. The embodied energy and annual energy outputs have been used for evaluation of the energy metrics. For hybrid PV module, it has been observed that the EPBT gets significantly reduced by taking into account the increase in annual energy availability of the thermal energy in addition to the electrical energy. The values of EPF and LCCE of hybrid PV module become higher as expected. (author)

Information report from the Economic Affairs commission on photovoltaic energy; Rapport d'information depose en application de l'article 145 du reglement par la commission des affaires economiques sur l'energie photovoltaique

Energy Technology Data Exchange (ETDEWEB)

NONE

2009-07-01

Today and for several years to come, photovoltaic energy represents only a minimal part of the world's electric power production. Photovoltaic energy is only at its beginnings, however several countries have already taken opportunities in the business. This report gives a comprehensive information about photovoltaic energy (basic principles, conversion systems, photovoltaic power plants, incentive programs in other developed countries, regulations ...) and arguments for the development of a structured photovoltaic energy policy in France.

A mechanical energy harvested magnetorheological damper with linear-rotary motion converter

Science.gov (United States)

Chu, Ki Sum; Zou, Li; Liao, Wei-Hsin

2016-04-01

Magnetorheological (MR) dampers are promising to substitute traditional oil dampers because of adaptive properties of MR fluids. During vibration, significant energy is wasted due to the energy dissipation in the damper. Meanwhile, for conventional MR damping systems, extra power supply is needed. In this paper, a new energy harvester is designed in an MR damper that integrates controllable damping and energy harvesting functions into one device. The energy harvesting part of this MR damper has a unique mechanism converting linear motion to rotary motion that would be more stable and cost effective when compared to other mechanical transmissions. A Maxon motor is used as a power generator to convert the mechanical energy into electrical energy to supply power for the MR damping system. Compared to conventional approaches, there are several advantages in such an integrated device, including weight reduction, ease in installation with less maintenance. A mechanical energy harvested MR damper with linear-rotary motion converter and motion rectifier is designed, fabricated, and tested. Experimental studies on controllable damping force and harvested energy are performed with different transmissions. This energy harvesting MR damper would be suitable to vehicle suspensions, civil structures, and smart prostheses.

Hybrid photovoltaic system control for enhancing sustainable energy. Economic aspects

International Nuclear Information System (INIS)

Leva, Sonia; Roscia, Mariacristina; Zaninelli, Dario

2005-01-01

The paper introduces hybrid photovoltaic/diesel generation systems for supplying remote power plant taking into account the enhancement of sustainable energy on the economic point of view. In particular, a new monitoring and control device is presented in order to carry out the optimum energy flows and a cost evaluation is performed on a real plant showing the effect and weight of the economical sustainability and economical saving. (authors)

U.S. Department of Energy Photovoltaic Energy Program Contract Summary: Fiscal Year 2000

Energy Technology Data Exchange (ETDEWEB)

Surek, T.

2001-02-21

This report summarizes the in-house and subcontracted research and development (R and D) activities under the National Center for Photovoltaics (NCPV) and U.S. Department of Energy (DOE) National Photovoltaics Program from October 1, 1999, through September 30, 2000 (FY 2000). The mission of the DOE National Photovoltaics Program is to make PV a significant part of the domestic economy-as an industry and an energy resource. The two primary goals of the national program are to (1) maintain the U.S. industry's world leadership in research and technology development and (2) help the U.S. industry remain a major, profitable force in the world market. The NCPV is part of the National PV Program and provides leadership and support to the national program toward achieving its mission and goals. This Contract Summary for fiscal year (FY) 2000 documents some 179 research projects supported by the PV Program, performed by 107 organizations in 32 states, including 69 projects performed by universities and 60 projects performed by our industry partners. Of the total FY 2000 PV Program budget of $65.9 million, the industry and university research efforts received $36.9 million, or nearly 56%. And, of this amount, more than 93% was for contractors selected on a competitive basis. Much of the funding to industry was matched by industry cost-sharing. Each individual effort described in this summary represents another step toward improving PV manufacturing, performance, cost, and applications, and another step toward accomplishing the DOE PV Program's overall mission.

Hydraulic Evaluation of the Crest Wing Wave Energy Converter

DEFF Research Database (Denmark)

Kofoed, Jens Peter; Antonishen, Michael Patrick

This report presents the results of an experimental study of the wave energy converting abilities of the Crest Wing wave energy converter (WEC). The Crest Wing is a WEC that uses its movement in matching the shape of an oncoming wave to generate power. Model tests have been performed using a scale...... model (length scale 1:30), provided by WaveEnergyFyn, in regular and irregular wave states that can be found in Assessment of Wave Energy Devices. Best Practice as used in Denmark (Frigaard et al., 2008). The tests were carried out at Dept. of Civil Engineering, Aalborg (Frigaard et al., 2008......). The tests were carried out at Dept. of Civil Engineering, Aalborg University (AAU) in the 3D deep water wave tank. The displacement and force applied to a power take off system, provided by WaveEnergyFyn, were measured and used to calculate total power take off....

Electric properties of organic and mineral electronic components, design and modelling of a photovoltaic chain for a better exploitation of the solar energy; Proprietes electriques des composants electroniques mineraux et organiques, conception et modelisation d'une chaine photovoltaique pour une meilleure exploitation de l'energie solaire

Energy Technology Data Exchange (ETDEWEB)

Aziz, A

2006-11-15

The research carried out in this thesis relates to the mineral, organic electronic components and the photovoltaic systems. Concerning the mineral semiconductors, we modelled the conduction properties of the structures metal/oxide/semiconductor (MOS) strongly integrated in absence and in the presence of charges. We proposed a methodology allowing characterizing the ageing of structures MOS under injection of the Fowler Nordheim (FN) current type. Then, we studied the Schottky diodes in polymers of type metal/polymer/metal. We concluded that: The mechanism of the charges transfer, through the interface metal/polymer, is allotted to the thermo-ionic effect and could be affected by the lowering of the potential barrier to the interface metal/polymer. In the area of photovoltaic energy, we conceived and modelled a photovoltaic system of average power (100 W). We showed that the adaptation of the generator to the load allows a better exploitation of solar energy. This is carried out by the means of the converters controlled by an of type MPPT control provided with a detection circuit of dysfunction and restarting of the system. (author)

Modeling, Dynamics, Bifurcation Behavior and Stability Analysis of a DC-DC Boost Converter in Photovoltaic Systems

Science.gov (United States)

Zhioua, M.; El Aroudi, A.; Belghith, S.; Bosque-Moncusí, J. M.; Giral, R.; Al Hosani, K.; Al-Numay, M.

A study of a DC-DC boost converter fed by a photovoltaic (PV) generator and supplying a constant voltage load is presented. The input port of the converter is controlled using fixed frequency pulse width modulation (PWM) based on the loss-free resistor (LFR) concept whose parameter is selected with the aim to force the PV generator to work at its maximum power point. Under this control strategy, it is shown that the system can exhibit complex nonlinear behaviors for certain ranges of parameter values. First, using the nonlinear models of the converter and the PV source, the dynamics of the system are explored in terms of some of its parameters such as the proportional gain of the controller and the output DC bus voltage. To present a comprehensive approach to the overall system behavior under parameter changes, a series of bifurcation diagrams are computed from the circuit-level switched model and from a simplified model both implemented in PSIM© software showing a remarkable agreement. These diagrams show that the first instability that takes place in the system period-1 orbit when a primary parameter is varied is a smooth period-doubling bifurcation and that the nonlinearity of the PV generator is irrelevant for predicting this phenomenon. Different bifurcation scenarios can take place for the resulting period-2 subharmonic regime depending on a secondary bifurcation parameter. The boundary between the desired period-1 orbit and subharmonic oscillation resulting from period-doubling in the parameter space is obtained by calculating the eigenvalues of the monodromy matrix of the simplified model. The results from this model have been validated with time-domain numerical simulation using the circuit-level switched model and also experimentally from a laboratory prototype. This study can help in selecting the parameter values of the circuit in order to delimit the region of period-1 operation of the converter which is of practical interest in PV systems.

Stochastic control of inertial sea wave energy converter.

Science.gov (United States)

Raffero, Mattia; Martini, Michele; Passione, Biagio; Mattiazzo, Giuliana; Giorcelli, Ermanno; Bracco, Giovanni

2015-01-01

The ISWEC (inertial sea wave energy converter) is presented, its control problems are stated, and an optimal control strategy is introduced. As the aim of the device is energy conversion, the mean absorbed power by ISWEC is calculated for a plane 2D irregular sea state. The response of the WEC (wave energy converter) is driven by the sea-surface elevation, which is modeled by a stationary and homogeneous zero mean Gaussian stochastic process. System equations are linearized thus simplifying the numerical model of the device. The resulting response is obtained as the output of the coupled mechanic-hydrodynamic model of the device. A stochastic suboptimal controller, derived from optimal control theory, is defined and applied to ISWEC. Results of this approach have been compared with the ones obtained with a linear spring-damper controller, highlighting the capability to obtain a higher value of mean extracted power despite higher power peaks.

Energy management algorithm for an optimum control of a photovoltaic water pumping system

International Nuclear Information System (INIS)

Sallem, Souhir; Chaabene, Maher; Kamoun, M.B.A.

2009-01-01

The effectiveness of photovoltaic water pumping systems depends on the adequacy between the generated energy and the volume of pumped water. This paper presents an intelligent algorithm which makes decision on the interconnection modes and instants of photovoltaic installation components: battery, water pump and photovoltaic panel. The decision is made by fuzzy rules on the basis of the Photovoltaic Panel Generation (PVPG) forecast during a considered day, on the load required power, and by considering the battery safety. The algorithm aims to extend operation time of the water pump by controlling a switching unit which links the system components with respect to multi objective management criteria. The algorithm implementation demonstrates that the approach extends the pumping period for more than 5 h a day which gives a mean daily improvement of 97% of the water pumped volume.

Citywide Impacts of Cool Roof and Rooftop Solar Photovoltaic Deployment on Near-Surface Air Temperature and Cooling Energy Demand

Science.gov (United States)

Salamanca, F.; Georgescu, M.; Mahalov, A.; Moustaoui, M.; Martilli, A.

2016-10-01

Assessment of mitigation strategies that combat global warming, urban heat islands (UHIs), and urban energy demand can be crucial for urban planners and energy providers, especially for hot, semi-arid urban environments where summertime cooling demands are excessive. Within this context, summertime regional impacts of cool roof and rooftop solar photovoltaic deployment on near-surface air temperature and cooling energy demand are examined for the two major USA cities of Arizona: Phoenix and Tucson. A detailed physics-based parametrization of solar photovoltaic panels is developed and implemented in a multilayer building energy model that is fully coupled to the Weather Research and Forecasting mesoscale numerical model. We conduct a suite of sensitivity experiments (with different coverage rates of cool roof and rooftop solar photovoltaic deployment) for a 10-day clear-sky extreme heat period over the Phoenix and Tucson metropolitan areas at high spatial resolution (1-km horizontal grid spacing). Results show that deployment of cool roofs and rooftop solar photovoltaic panels reduce near-surface air temperature across the diurnal cycle and decrease daily citywide cooling energy demand. During the day, cool roofs are more effective at cooling than rooftop solar photovoltaic systems, but during the night, solar panels are more efficient at reducing the UHI effect. For the maximum coverage rate deployment, cool roofs reduced daily citywide cooling energy demand by 13-14 %, while rooftop solar photovoltaic panels by 8-11 % (without considering the additional savings derived from their electricity production). The results presented here demonstrate that deployment of both roofing technologies have multiple benefits for the urban environment, while solar photovoltaic panels add additional value because they reduce the dependence on fossil fuel consumption for electricity generation.

Rancang Bangun Maximum Power Point Tracking pada Panel Photovoltaic Berbasis Logika Fuzzy di Buoy Weather Station

Directory of Open Access Journals (Sweden)

Bayu Prima Juliansyah Putra

2013-09-01

Full Text Available Salah satu aplikasi yang sering digunakan dalam bidang energi terbarukan adalah panel photovoltaic. Panel ini memiliki prinsip kerja berdasarkan efek photovoltaic dimana lempengan logam akan menghasilkan energi listrik apabila diberi intensitas cahaya. Untuk menghasilkan daya keluaran panel yang maksimal, maka diperlukan suatu algoritma yang biasa disebut Maximum Power Point Tracking (MPPT.MPPT yang diterapkan pada sistem photovoltaic berfungsi untuk mengatur nilai tegangan keluaran panel sehingga titik ker-janya beroperasi pada kondisi maksimal. Algoritma MPPT pada panel ini telah dilakukan dengan menggunakan logika fuzzy melalui mikrokontroler Arduino Uno sebagai pem-bangkit sinyal Pulse Width Modulation (PWM yang akan dikirimkan menuju DC-DC Buck Boost Converter. Keluaran dari buck boost converterakan dihubungkan secara langsung dengan buoy weather station untuk menyuplai energi listrik tiap komponen yang berada di dalamnya. Untuk menguji performansi dari algoritma MPPT yang telah dirancang, maka sistem akan diuji menggunakan variasi beban antara metode direct-coupled dengan MPPT menggunakan logika fuzzy. Hasil pengujian menunjukkan bahwa MPPT dengan logika fuzzy dapat menghasilkan daya maksimum daripada direct-coupled. Pada sistem panel photovoltaic ini memiliki range efisiensi 33.07589 % hingga 74.25743 %. Daya mak-simal dapat dicapai oleh sistem untuk tiap variasi beban dan efisiensi maksimal dapat dicapai pada beban 20 Ohm dari hasil pengujian sistem MPPT.

Study of electrical and thermal characteristics of inverters for grid-connected photovoltaic systems; Estudo de caracteristicas eletricas e termicas de inversores para sistemas fotovoltaicos conectados a rede

Energy Technology Data Exchange (ETDEWEB)

Rampinelli, Giuliano Arns

2010-12-15

Grid-connected photovoltaic systems directly convert solar energy into electrical energy delivering to the distribution grid a clean and renewable energy. These systems are basically formed by an array of photovoltaic modules and inverters. The inverters are responsible for converting direct current to alternating current. A study of electrical and thermal characteristics of inverters used in grid-connected photovoltaic systems from a theoretical and experimental analysis. The inverters tests were carried out in two stages: the first stage was performed at Solar Energy Lab. of the Federal University of Rio Grande do Sul (UFRGS), Brazil, where it was used a 4,8 kW{sub p} grid-connected photovoltaic system and ten inverters of different manufacturers. The inverters electrical characteristics measured and analyzed were: direct current to alternating current conversion efficiency, maximum power point tracker efficiency, power factor and harmonic distortion in current and voltage. Inverters thermal testing was also conducted and its results are presented ana analyzed. The second stage of the experimental tests was performed at Photovoltaic Solar Energy Lab. at CIEMAT in Spain. It was used 3 kW{sub p} photovoltaic system and seven inverters of different manufacturers. The inverters are single-phase, up to 5 kW and different topologies (high frequency transformer, low frequency transformer and transformerless). The influence of DC voltage input in the behavior of DC to AC conversion efficiency and power factor was analyzed. The results of the tests allowed the development of mathematical models that describe the electrical and thermal behavior of the inverters. The proposed mathematical models were inserted into computer simulation software developed at UFRGS named FVConect. The evolution of the simulation results compared to the experimental results validates the proposed models. The analysis of the behavior of the inverters improves the understanding of the operating os

Photovoltaic solar energy: which realities for 2020? Summarized synthesis; Solaire photovoltaique: quelles realites pour 2020?. Synthese resumee

Energy Technology Data Exchange (ETDEWEB)

NONE

2011-07-01

This report first describes the situation of the photovoltaic as situated at a crossroad with strong development possibilities for the French photovoltaic sector. It presents the photovoltaic energy as a competitive, regulatory and ecologic one, and therefore inescapable. It outlines stakes and obstacles of the French situation regarding the development of this sector. It highlights the economic and social benefit investing in this sector. Some propositions are stated for the promotion of the photovoltaic solar sector. Challenges are identified

System of supervision and data acquisition applied to photovoltaic pumping; Sistema de aquisicao e supervisao de dados aplicado a bombeamento fotovoltaico

Energy Technology Data Exchange (ETDEWEB)

Aquino, Andre Teixeira de; Juca, Sandro Cesar Silveira; Cavalcante, Tiago Malveira [Centro Federal de Educacao Tecnologica de Petrolina (CEFET), PE (Brazil). Area da Industria; Carvalho, Paulo Cesar Marques de [Universidade Federal do Ceara (UFC), Fortaleza, CE (Brazil). Dept. de Engenharia Eletrica

2008-07-01

The work describes a micro controlled acquisition data system of low cost (Simlogger), as well as analyzing the results with implementation in a pumping water system that uses the photovoltaic conversion of the solar energy to foretell optimum day period for the pumps drive increasing, thus, the converted energy efficiency. Voltage values measurements had been carried through during two days in a solar pump by five photovoltaic panels in parallel. The readings had been carried through in intervals of 10 minutes and the data rescue was made using a supervision software that generates analog graphs of obtained data in a personal computer. This acquisition system makes possible the planning of solar energy optimum period for conversion in potential energy through the water pumping for high reservoirs. (author)

Simulation study of air and water cooled photovoltaic panel using ANSYS

Science.gov (United States)

Syafiqah, Z.; Amin, N. A. M.; Irwan, Y. M.; Majid, M. S. A.; Aziz, N. A.

2017-10-01

Demand for alternative energy is growing due to decrease of fossil fuels sources. One of the promising and popular renewable energy technology is a photovoltaic (PV) technology. During the actual operation of PV cells, only around 15% of solar irradiance is converted to electricity, while the rest is converted into heat. The electrical efficiency decreases with the increment in PV panel’s temperature. This electrical energy is referring to the open-circuit voltage (Voc), short-circuit current (Isc) and output power generate. This paper examines and discusses the PV panel with water and air cooling system. The air cooling system was installed at the back of PV panel while water cooling system at front surface. The analyses of both cooling systems were done by using ANSYS CFX and PSPICE software. The highest temperature of PV panel without cooling system is 66.3 °C. There is a decrement of 19.2% and 53.2% in temperature with the air and water cooling system applied to PV panel.

Cascaded H-Bridge with Bidirectional Boost Converters for Energy Storage

DEFF Research Database (Denmark)

Trintis, Ionut; Munk-Nielsen, Stig; Teodorescu, Remus

2011-01-01

This paper presents the design and control of a cascaded H-bridge converter for energy storage with bidirectional boost converter as charge/discharge unit. The disadvantage of the second harmonic on the main energy storage unit as well as its voltage variation with the state of charge is solved...... by this structure. The independent phase grid control is proposed for this topology. This strategy is able to control the average dc-link voltage for each phase independently and to balance the cells capacitors voltages. The balance of the energy storage units is achieved by controlling independently each cell...

Control of the DC-DC Converter used into Energy Generation System

International Nuclear Information System (INIS)

Bizon, Nicu; Oproescu, Mihai

2006-01-01

This paper presents an investigation of the DC-DC Converter controller used into Energy Generation System. The full bridge is used into an Energy Generation System (EGS) as second power interface between the energy source and the high DC bus. The simulation results show that the DC-DC Converter behavior can be improved using a well designed PI control surface. The used Simulink models for the EGS blocks and some design considerations are presented, too. (authors)

Experimental Study on the Langlee Wave Energy Converter

DEFF Research Database (Denmark)

Pecher, Arthur; Kofoed, Jens Peter; Weisz, A.

This report presents the results of an experimental study of the wave energy converting abilities of the Langlee wave energy converter (WEC). It focused mainly on evaluating the power generating capabilities of the device, including investigations of the following issues: Scaling ratiosPTO loadingWave...... height and wave period dependencyOblique incoming waves and directional spreading of waves (3D waves)Damping platesMooring forces and fixed structure setupPitch, surge and heave motion During the study the model supplied by the client (Langlee Wave Power AS) has been heavily instrumented - up to 23...... different instruments was deployed to measure and record data. Tests were performed at scales of 1:30 and 1:20 based on the realized reference wave states....

Solar thermal power and photovoltaic energy are both developing; Solaire a concentration et solaire photovoltaique: la main dans la main

Energy Technology Data Exchange (ETDEWEB)

Le Jannic, N.; Houot, G.

2010-11-15

Thermodynamic solar energy and photovoltaic energy are expected to reach together a quarter of the world electricity production by 2050. In France the development of thermodynamic solar plants is hampered by the high cost of land in the sunny regions. As for photovoltaic energy, France has the potentiality to become an important producer. Since 2006, the French government has supported photovoltaic energy by proposing incentive electricity purchase prices guaranteed for 20 years. In 2006, the Ines research institute was founded, one of its research fields is the development of high yield silicon cells. (A.C.)

Control Method Based on Demand Response Needs of Isolated Bus Regulation with Series-Resonant Converters for Residential Photovoltaic Systems

Directory of Open Access Journals (Sweden)

Shu-Huai Zhang

2017-05-01

Full Text Available Considering the effects of isolation and high efficiency, a series-resonant DC-DC converter (L-L-C type, with two inductors and a capacitor has been introduced into a residential photovoltaic (PV generation and storage system in this work, and a voltage gain curve upwarp drifting problem was found. In this paper, the reason of upwarp drifting in the voltage gain curve is given, and a new changing topological control method to solve the voltage regulation problem under light load conditions is proposed. Firstly, the ideal and actual first harmonic approximation (FHA models are given, and this drifting problem is ascribed to the multiple peaks of higher-order resonance between resonant tank and parasitic capacitors. Then the paper presents the pulse-frequency-modulation (PFM driver signals control method to translate the full-bridge LLC into a half-bridge LLC converter, and with this method the voltage gain could easily be reduced by half. Based on this method, the whole voltage and resonant current sharing control methods in on-line and off-line mode are proposed. The parameters design and optimization methods are also discussed in detail. Finally, a residential PV system platform based on the proposed parallel 7-kW full-bridge LLC converter is built to verify the proposed control method and theoretical analysis.

Integration of plug-in hybrid electric vehicles (PHEV) with grid connected residential photovoltaic energy systems

Science.gov (United States)

Nagarajan, Adarsh; Shireen, Wajiha

2013-06-01

This paper proposes an approach for integrating Plug-In Hybrid Electric Vehicles (PHEV) to an existing residential photovoltaic system, to control and optimize the power consumption of residential load. Control involves determining the source from which residential load will be catered, where as optimization of power flow reduces the stress on the grid. The system built to achieve the goal is a combination of the existing residential photovoltaic system, PHEV, Power Conditioning Unit (PCU), and a controller. The PCU involves two DC-DC Boost Converters and an inverter. This paper emphasizes on developing the controller logic and its implementation in order to accommodate the flexibility and benefits of the proposed integrated system. The proposed controller logic has been simulated using MATLAB SIMULINK and further implemented using Digital Signal Processor (DSP) microcontroller, TMS320F28035, from Texas Instruments

Clustering of cycloidal wave energy converters

Science.gov (United States)

Siegel, Stefan G.

2016-03-29

A wave energy conversion system uses a pair of wave energy converters (WECs) on respective active mountings on a floating platform, so that the separation of the WECs from each other or from a central WEC can be actively adjusted according to the wavelength of incident waves. The adjustable separation facilitates operation of the system to cancel reactive forces, which may be generated during wave energy conversion. Modules on which such pairs of WECs are mounted can be assembled with one or more central WECs to form large clusters in which reactive forces and torques can be made to cancel. WECs of different sizes can be employed to facilitate cancelation of reactive forces and torques.

Prototype Testing of the Wave Energy Converter Wave Dragon

DEFF Research Database (Denmark)

Kofoed, Jens Peter; Frigaard, Peter; Friis-Madsen, Erik

2006-01-01

The Wave Dragon is an offshore wave energy converter of the overtopping type. It consists of two wave reflectors focusing the incoming waves towards a ramp, a reservoir for collecting the overtopping water and a number of hydro turbines for converting the pressure head into power. In the period...... from 1998 to 2001 extensive wave tank testing on a scale model was carried at Aalborg University. Then, a 57!27 m wide and 237 tonnes heavy (incl. ballast) prototype of the Wave Dragon, placed in Nissum Bredning, Denmark, was grid connected in May 2003 as the world’s first offshore wave energy...... converter. The prototype is fully equipped with hydro turbines and automatic control systems, and is instrumented in order to monitor power production, wave climate, forces in mooring lines, stresses in the structure and movements of the Wave Dragon. In the period May 2003 to January 2005 an extensive...

Prototype Testing of the Wave Energy Converter Wave Dragon

DEFF Research Database (Denmark)

Kofoed, Jens Peter; Frigaard, Peter Bak; Friis-Madsen, Erik

2004-01-01

The Wave Dragon is an offshore wave energy converter of the overtopping type. It consists of two wave reflectors focusing the incoming waves towards a ramp, a reservoir for collecting the overtopping water and a number of hydro turbines for converting the pressure head into power. In the period...... from 1998 to 2001 extensive wave tank testing on a scale model was carried at Aalborg University. Then, a 57 x 27 m wide and 237 tonnes heavy (incl. ballast) prototype of the Wave Dragon, placed in Nissum Bredning, Denmark, was grid connected in May 2003 as the world's first offshore wave energy...... converter. The prototype is fully equipped with hydro turbines and automatic control systems, and is instrumented in order to monitor power production, wave climate, forces in mooring lines, stresses in the structure and movements of the Wave Dragon. During the last months, extensive testing has started...

Urban photovoltaic electricity policies

Energy Technology Data Exchange (ETDEWEB)

NONE

2009-10-15

This report for the International Energy Agency (IEA) made by Task 10 of the Photovoltaic Power Systems (PVPS) programme takes a look at urban photovoltaic electricity policies. 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 as a significant and sustainable renewable energy option. The objective of Task 10 is stated as being to enhance the opportunities for wide-scale, solution-oriented application of photovoltaics in the urban environment. The goal of the study presented was to evaluate a standardised basis for urban policies regarding photovoltaic integration in a set of cities in the countries participating in the IEA's Task 10, Urban Scale PV. The investigation was focused on three topics: the present state of the policies, the prospects for future policies fostering photovoltaic deployment and the prospects for future policies to cope with large-scale photovoltaic integration. The first section analyses the state of the policies; this analysis is then confirmed in section 2, which deals with present obstacles to PV deployment and solutions to overcome them. The third section investigates future prospects for PV deployment with the question of mastering large scale integration. The report concludes that cities could formulate urban solutions by developing integrated, specific provisions for PV deployment in their urban infrastructure planning.

Sunlight to hydrogen conversion: Design optimization and energy management of concentrated photovoltaic (CPV-Hydrogen) system using micro genetic algorithm

KAUST Repository

Burhan, Muhammad

2016-02-14

Owing to the intermittent solar irradiance from cloud cover in the diurnal period and unavailability at night time, the practical design of a solar system requires energy backup storage for an uninterrupted supply or for off-grid operation. However, for highly efficient CPV (concentrated photovoltaic) system, the literature is lacking for energy management and optimization algorithm and tool for standalone operation. In this paper, a system with CPV and electrolyser is presented where beam irradiance of sunlight is harnessed to convert the instantaneously generated electricity into useful Hydrogen/Oxygen gas, where they can be stored and re-used for downstream applications such as the fuel cells, etc. The multi-variable design and multi-objective optimization strategies are proposed and presented for a standalone operation of the CPV-Hydrogen system as well as their system performances, particularly electrical rating of CPV based upon the real weather data of Singapore. © 2016 Elsevier Ltd.

High efficiency β radioisotope energy conversion using reciprocating electromechanical converters with integrated betavoltaics

Science.gov (United States)

Duggirala, Rajesh; Li, Hui; Lal, Amit

2008-04-01

We demonstrate a 5.1% energy conversion efficiency Ni63 radioisotope power generator by integrating silicon betavoltaic converters with radioisotope actuated reciprocating piezoelectric unimorph cantilever converters. The electromechanical energy converter efficiently utilizes both the kinetic energy and the electrical charge of the 0.94μW β radiation from a 9mCi Ni63 thin film source to generate maximum (1) continuous betavoltaic electrical power output of 22nW and (2) pulsed piezoelectric electrical power output of 750μW at 0.07% duty cycle. The electromechanical converters can be potentially used to realize 100year lifetime power sources for powering periodic sampling remote wireless sensor microsystems.

An Advanced Photovoltaic Array Regulator Module

Science.gov (United States)

Button, Robert M.

1996-01-01

Current trends in satellite design are focused on developing small, reliable, and inexpensive spacecraft. To that end, a modular power management and distribution system is proposed which will help transition the aerospace industry towards an assembly line approach to building spacecraft. The modular system is based on an innovative DC voltage boost converter called the Series Connected Boost Unit (SCBU). The SCBU uses any isolating DC-DC converter and adds a unique series connection. This simple modification provides the SCBU topology with many advantages over existing boost converters. Efficiencies of 94-98%, power densities above 1,000 W/kg, and inherent fault tolerance are just a few of the characteristics presented. Limitations of the SCBU technology are presented, and it is shown that the SCBU makes an ideal photovoltaic an-ay regulator. A set of photovoltaic power system requirements are presented that can be applied to almost any low Earth orbit satellite. Finally, a modular design based on the series connected boost unit is outlined and functional descriptions of the components are given.

Energy analysis of solar photovoltaic module production in India

International Nuclear Information System (INIS)

Prakash, R.; Bansal, N.K.

1995-01-01

The objective of this article is to evaluate the energy consumption in solar photovoltaic (SPV) module production in India and examine its implications for large-scale introduction of SPV plants in the country. Data on energy used in SPV production were collected from existing manufacturing facilities in the country. The energy payback period turns out to be approximately 4 years. This is comparable to energy payback periods of similar modules produced internationally. However, if an ambitious program of introducing SPV power production is undertaken to contribute substantially to the power scenario in the country, an annual growth rate beyond 21% will render the program an energy sink rather than an energy source, as borne out by dynamic energy analysis. Policy implications are also discussed in light of this analysis

Study on High energy efficiency photovoltaic facility agricultural system in tropical area of China

Directory of Open Access Journals (Sweden)

Ge Zhiwu

2018-01-01

Full Text Available The photovoltaic facility agriculture is developing rapidly in recent years, but there are many problems brought out, even in some important demonstration projects, due to the lack of standards. In order to solve some of these problems, we set up a photovoltaic facilities agricultural system in Guilinyang University City, Haikou, China and make an in-depth study on the photovoltaic facility agricultural system and its related problems. In this paper we disclose some of the experimental results. We plant corianders under two kinds of solar cell panels and general double glass assembly already sold on the market. Experiments showed that the square format cell panels are much better than row type, and the next one is general double glass assembly sold on the market, the last is the case without any shelter. 30 days after planting, the height of coriander plants are 50mm, 30mm, 23mm and 20mm correspondingly. The two typical solar cell panels have gaps between cells, and can save much more energy and improve power generation efficiency, we arrange the panels at optimum tilted angle, and design the system as open structure to save more energy. The photovoltaic facilities agricultural system we set up in Guilinyang University City can achieve much high solar energy efficiency than others and has broad application prospects.

Bio-Inspired Photon Absorption and Energy Transfer for Next Generation Photovoltaic Devices

Science.gov (United States)