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The purpose of this paper is to explore citizens’ willingness to invest in photovoltaics.

To meet the aim of the research, a questionnaire survey was conducted in the island of Evia in Greece using the method of random stratified sampling. A total of 366 responses were analyzed using both descriptive and inductive statistics methods, such as principal components analysis, K-means cluster analysis, discriminant analysis and binary logistic regression.

The research results indicate that 73per cent of the respondents would invest in renewable energy sources, whereas 55per cent of them would specifically invest in photovoltaics. Regarding their views on photovoltaics, three components were extracted; photovoltaics positive effects, facilitations for investments in photovoltaics and photovoltaics’ performance. Area of residence, annual income and the above-mentioned three components of views on photovoltaics were found to be statistically significant for the dichotomous variable of willingness to invest in photovoltaics. Among the examined variables, photovoltaics performance found to contribute the most in increasing respondents’ willingness to invest in photovoltaics.

The study filled the literature gap concerning citizens’ willingness to invest in photovoltaics in Greece. Furthermore, the research results made feasible to understand the factors that can lead in an investment decision for photovoltaics.

This paper aims to present a numerical study on the natural convection, which operates either as an evaporator or condenser unit of the heat pump system to pre-cool and pre-heat the ambient fresh air.

This study focuses on natural air cooling or heating within the air channel considering the double skin configuration. Particular focus is given to the analysis of airflow and the heat transfer processes in an air channel to cool or heat the ambient fresh air. In this study, the physical model consists of one wall, either heated uniformly or cooled uniformly, whereas the other wall is adiabatic.

The results show that the variation of both velocity and temperature is observed as the flow transition occurs at the evaporator or condenser wall. In either case, the temperature rises in the range of 6.3–8.4°C with an increase in mass flow rate from 0.07–0.08 kg/s in the photovoltaic thermal condenser part, while in the photovoltaic thermal evaporator part, the change in mass flow rate from 0.048–0.061 kg/s causes a decrease in temperature from 7.1–4.5°C.

The solar-assisted photovoltaic thermal heat pump system, in building façade having an air layer application, is feasible for pre-heating and pre-cooling the ambient fresh air and also reduces the energy needed to treat the fresh air.

The influence of condensing and evaporating temperature under natural convection mode in double skin conformation is considered for pre-heating and pre-cooling of ambient fresh air.

Even though copper–tungsten has shown signs of potentials, relatively little is currently known about its appropriateness for photovoltaic application. This paper aims to evaluate the suitability of copper-tungs oxides as photovoltaic absorbers while investigating the consequences of oxygen content variation.

Using profilometry, Hall measurements, Seebeck test and spectrophotometry, grown samples were defined. Samples of 5 standard cubic centimeters per minute (sccm) and 7 sccm exhibited appropriate characteristics and were further tested using personal computer one dimension (PC1D) computational simulation at the system stage. To grow materials with an average thickness below 0.45 µm, magnetron co-sputtering was used. Three sample sets, varied by oxygen flow rate, were made with flow rates of 5sccm, 7sccm and 9sccm, respectively.

Some samples proved to be effective absorbers, using a cadmium telluride device as the criterion of output calculation, with one sample chosen as ideal for each type of flow rate. For the chosen samples, an optimum thickness was also obtained, i. It was discovered that thinner cells, optimal for both groups with 0.6 µm, performed better to than other thicknesses.

The material also demonstrated prospects for applications in window layers, but more needs to be known.

Thin film material properties and their operating processes are relatively complex, so it is important to find simple and cost-effective ways to forecast performance. While relatively new, numerical modeling has proven to be very useful in defining the critical properties of thin film devices, thereby helpful for predictions of performance. Solar cell capacitance simulator one dimension, amorphous semiconductor analysis, personal computer one dimension (PC1D), analysis of micro-electronic and photonic structures and automat for simulation for heterostructures (33) are several common models in the thin film industry. Due to its availability and relative ease of use, PC1D was used in this project.

As the search for the balance among performance, cost, reliability and availability continue, more absorber components continue to evolve, notably from the chalcogenides. Because of their ability to absorb light, ternary transition metal chalcogenides are useful in the production of hydrogen and in the energy storage sector, as well as in the production of light-emitting diodes and solar photovoltaic (PV).

There are several methods for the manufacture of copper–tungsten alloys, but the process of combinatorial sputtering of magnetrons provides satisfactory results even for the manufacture of various other materials. Cu₂WSe₄, an excellent alternative to sputtering, is one of the very few copper–tungsten selenide materials tested, synthesized by hot simple injection to have strong crystallinity and lacks impurity. The optical properties of colloidal Cu₂WSe₄ show that Schottky diode–like behaviors are present in the material, suggesting its potential for use in solar cells. Cu-W alloys could have a lot more to give the PV industry, by all indications. Further exploration of the oxides by this work is thus justified. Transparent conducting oxides, interfacial layers or charge-transporting compounds are commonly used as transition metal oxides. Nevertheless, as absorbers, metal oxides such as BiFeO₃ and the traditionally highly studied Cu₂O have been tested, with Cu₂O showing a conversion efficiency of up to 10% under particular conditions. This displays strong electronic and optical properties, so there might be some possibility of studying other PV absorption metal oxides. The optical properties of colloidal Cu₂WSe₄ show that Schottky diode–like behaviors are present in the material, suggesting its potential for use in solar cells.

This paper aims to focus on the trade-off between losses and converter cost.

The continual development of power electronic converters, for a wide range of applications such as renewable energy systems (interfacing photovoltaic panels via power converters), is characterized by the requirements for higher efficiency and lower production costs. To achieve such challenging objectives, a computer-aided design optimization based on genetic algorithms is developed in Matlab environment. The elitist non-dominated sorting genetic algorithm is used to perform search and optimization, whereas averaged models are used to estimate power losses in different semiconductors devices. The design problem requires minimizing the losses and cost of the boost converter under electrical constraints. The optimization variables are, as for them, the switching frequency, the boost inductor, the DC capacitor and the types of semiconductor devices (IGBT and MOSFET). It should be pointed out that boost topology is considered in this paper but the proposed methodology is easily applicable to other topologies.

The results show that such design methodology for DC-DC converters presents several advantages. In particular, it proposes to the designer a set of solutions – as an alternative of a single one – so that the authors can choose a posteriori the adequate solution for the application under consideration. This then allows the possibility of finding the best design among all the available choices. Furthermore, the design values for the selected solution were obtainable components.

The authors focus on the general aspect of the discrete optimization approach proposed here. It can also be used by power electronics designers with the help of additional constraints in accordance with their specific applications. Furthermore, the use of such non-ideal average models with the multi-objective optimization is the original contribution of the paper and it has not been suggested so far.

This paper aims to propose a new MLI topology with reduced number of switches for photovoltaic applications. Multilevel inverters (MLIs) have been found to be prospective for renewable energy applications like photovoltaic cell, as they produce output voltage from numerous separate DC sources or capacitor banks with reduced total harmonic distortion (THD) because of a staircase like waveform. However, they endure from serious setbacks including larger number of capacitors, isolated DC sources, associated gate drivers and increased control difficulty for higher number of voltage levels.

This paper proposes a new three-phase multilevel DC-link inverter topology overpowering the previously mentioned problems. The proposed topology is designed for five and seven levels in Matlab/Simulink with gating pulse using multicarrier pulse width modulation. The hardware results are shown for a five-level MLI to witness the viability of the proposed MLI for medium voltage applications.

The comparison of the proposed topology with other conventional and other topologies in terms of switch count, DC sources and power loss has been made in this paper. The reduction of switches in proposed topology results in reduced power loss. The simulation and hardware show that the output voltage yields a very close sinusoidal voltage and lesser THD.

The proposed topology can be extended for any level of output voltage which is helpful for sustainable source application.

The purpose of this paper is to demonstrate the growing trend of developing and managing photovoltaic facilities owned by third parties in buildings, as a possible alternative to energy performance contracting.

Based on an established business model template, analysis is carried out on the framework of using third-party finance in the provision of photovoltaic facilities in buildings. Case studies in the USA and China enable comparison of policy tools enabling this approach.

While barriers exist in the common energy performance contracting approach for renewable installations owned by the building owner, vesting photovoltaic equipment with a third party for a certain period has become a viable business alternative as long as revenue is generated through a power purchase agreement or lease arrangement with the building owner.

The third-party ownership business model works better if sufficient policy incentives exist alongside the revenue brought about by renewable energy. Hence, governments have to create the right environment.

Win-win situations have been identified through case studies in countries with burgeoning renewable energy use in buildings, notably the USA and China, giving new insights on facilities management.

This paper aims to propose a new transformer-less inverter structure to reduce the common-mode leakage current in grid-connected photovoltaic (PV) systems.

The proposed circuit structure is the same as the conventional full-bridge inverter with three additional power switches in a triangular structure. These three power switches are between the bridge and the output filter, and they mitigate the common-mode leakage current flowing toward the PV panels’ capacitors. The common-mode leakage current mitigation is done through the three-direction clamping cell (TDCC) concept. By clamping the common-mode voltage to the middle voltage of the DC-link capacitors, the leakage current and the total harmonic distortion (THD) of the injected current to the grid is effectively reduced. Therefore, the efficiency is improved.

The switching modes and the control method are introduced. A comparison is carried out between the proposed structure and other solutions in the literature. The proposed topology and its respective control method are simulated by PSCAD/EMTDC software. The simulation results validate the advantages of the presented structure such as clamping the common-mode voltage and reducing leakage current and THD of injected current to the grid.

Presenting a single phase-improved inverter structure with low-leakage current for grid-connected PV power systems represents a significant original contribution to this work. The proposed structure can inject a sinusoidal current with low THD to the AC grid, and the power factor is unity on the AC side. In the half positive cycle, one of the switches in the TDCC is turned off under zero current. Besides, one of the other switches in TDCC is turned on with zero voltage and, therefore, its turn-on switching losses are zero. The efficiency of the proposed topology is high because of the reduction of leakage current and power losses. Accordingly, the presented topology can be a good solution to the leakage current elimination.

This paper aims to examine the design and control of a symmetric multilevel inverter (MLI) using grey wolf optimization and differential evolution algorithms.

The optimal modulation index along with the switching angles are calculated for an 11 level inverter. Harmonics are used to estimate the quality of output voltage and measuring the improvement of the power quality.

The simulation is carried out in MATLAB/Simulink for 11 levels of symmetric MLI and compared with the conventional inverter design. A solar photovoltaic array-based experimental setup is considered to provide the input for symmetric MLI. Field Programmable Gate Array (FPGA) based controller is used to provide the switching pulses for the inverter switches.

Attempted to develop a system with different optimization techniques.

This paper aims to review comprehensively the different voltage-boosting techniques and classifies according to their voltage gain, stress on the semiconductor devices, count of the total components and their prominent features. Hence, the focus is on non-isolated step-up converters. The converters categorized are analyzed according to their category with graphical representation.

Many converters have been reported in recent years in the literature to meet our power requirements from mill watts to megawatts. Fast growth in the generation of renewable energy in the past few years has promoted the selection of suitable converters that directly impact the behaviour of renewable energy systems. Step-up converters are a fast-emerging switching power converter in various power supply units. Researchers are more attracted to the derivation of novel topology with a high voltage gain, low voltage and current stress, high efficiency, low cost, etc.

A comparative study is done on critical metrics such as voltage gain, switch voltage stress and component count. Besides, the converters are also summarized based on their advantages and disadvantages. Furthermore, the areas that need to be explored in this field are identified and presented.

Types of analysis usually performed in dc converter and their needs with the areas need to be focused are not yet completely reviewed in most of the articles. This paper gives an eyesight on these topics. This paper will guide the researchers to derive and suggest a suitable topology for the chosen application. Moreover, it can be used as a handbook for studying the various topologies with their shortfalls, which will provide a way for researchers to focus.

At first, the organic/inorganic and hybrid PV materials by their electrical model are described. Then the proposed converter topology, circuit analysis and various operating modes of converter according to on/off timing of switches are investigated. The current and voltage in the converter components are illustrated and the voltage gain and switching stress of proposed converter are presented. Finally, to show the effectiveness of the proposed converter, the power loss analysis is provided and the simulation is done in PSIM software. In the last section, the advantages of the proposed topology of higher efficiency by lower number of components in compare with other conventional topologies are presented.

In this paper, an improved topology of DC-DC converter based on VL technique is proposed for Perovskite Solar cells (PeSCs). The PeSCs attracted a lot of interest due to their potential in combining the advantages of both organic and inorganic components. The proposed converter by using fewer components and higher output voltage generation in compare with conventional ones could be a good candidate for PeSCs due to lower efficiency of this cells. The performance of converter is expressed in continuous conduction mode (CCM) and discontinuous conduction mode (DCM), and the boundary conditions for the proposed converter is presented.

By using VL technique, this converter is used to boost the lower output voltage levels of PeSCs for grid connection. The PV cell output voltage is increased from 24.5 V to 106 V by proposed converter topology. The step-by-step voltage increasing by charging and discharging of inductor and capacitor is used for boosting the input voltage. By comparing other converters, there is no design complexity in the proposed converter structure, and the power loss is much reduced which increases the converter efficiency. On the other hand, due to using lower number of elements of energy storage elements such as inductors and capacitors, the converter cost is also diminished. Therefore, the design topology simplicity which result simple control algorithm and lower number of components which diminish the system cost by appropriate voltage boosting capability are the main advantages of this proposed topology for new PeSCs which don’t have enough efficiency in compare with old Si PV cells.

In this paper, by using the lower number of components a new structure of DC-DC converter based on the VL technique is proposed. The advantages of this converter such as the simplicity, easier control and high voltage gain by lower power loss, could make this converter a good candidate for new PeSCs where the system whole efficiency will be a critical point to have the unique properties of this new materials in lower loss.