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The purpose of this study is optimization of existing PV system and by making the optimization to reach the heights energy performance from the system.

The methodology used in this work is analytical as well as software using PV*SOL premium software. Both methods are used to achieve a more realistic analysis of the results achieved at the end of the work.

After analyzing the optimization of the PV system in terms of certain atmospheric conditions, it is clear that the optimization of the system is necessary. Through the optimization of the systems, a better performance of the system is achieved, as well as in the case in question, it affects the increase of the energy generated annually up to 500 kWh.

This work is the original work of the author, which represents a part of the topic of the doctorate.

The purpose of this paper is to investigate the potential of the experimental building integrated photovoltaic (BIPV) façade to cover net energy use in the adjacent office room. Electricity generated by PV panels was intended to cover the energy demand for the mechanical ventilation and the supplementary lighting. Analyses were performed for two orientations of the façade (east and west) and two occupancy profiles considering one or two employees per one office room.

The study was conducted by carrying detailed numerical analyses of energy produced by the BIPV façade and its consumption in adjacent office room. Calculations of energy generated by PV panels were made using simulation programme ESP-r. Advanced model, used in analyses, take into account dependence of the main electrical parameters of photovoltaic cell from temperature.

The findings reveal that energy generated by photovoltaic panels during transitional and cooling seasons is sufficient for lighting and ventilation requirement. However during winter months BIPV facade can cover energy demand only for ventilation.

The paper provides an original analysis of experimental BIPV façade system as a source of on-site produced renewable energy to cover energy demand in offices building under certain climate conditions. The results reported in presented paper shows the potential of BIPV facades and display this potential in a context of building net energy balance.

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.

The purpose of this paper is to report the system solution expressed in the form of a block diagram. In this paper, a multi-functional demonstrator of the interactive system designed to modelling, monitoring and validation of hybrid photovoltaic (PV) systems assisted by fuel cells and thermoelectric generators is presented. Technical parameters of demonstrator components such as: silicon PV modules, fuel cells, thermoelectric generators, gel batteries, control and monitoring systems are described.

The design shows the implementation of PV system modelling by four universal PV module simulators supported by two 65 W fuel cell and 12 modules, 6 W thermoelectric generators battery.

The paper provides practical proof that the combination of PV technology with both thermoelecric generators and fuel cells technologies shows promising results for the development of hybrid PV systems with increased effectiveness and efficiency.

The design idea can be developed for many applications gaining electricity from many distributed sources of wasted energy.

In practice, hybrid systems can be used to support the operation of classic PV systems, for example, working in various climatic conditions.

The proposed model demonstrates new technical solution leading to the enlargement of the PV systems application.

Increased investment of a photovoltaic (PV) array makes it essential for the client to attain better results from the PV system. The nonlinearity of the PV array and the revolution and rotation of the earth require the appliance of maximum power point tracking (MPPT) to the system. Accordingly, grid connected PV systems have turn out to be renowned, because they do not require battery back-ups to accomplish MPPT. Stand-alone systems could also attain MPPT; however, they require appropriate battery back-ups for this function.

This survey intends to formulate a review on the PV-based microgrid (MG) systems. Here, the literature analyses on diverse techniques associated with PV-based MG systems. It reviews 65 research papers and states the significant analysis. Initially, the analysis depicts various controllers that are contributed in different papers. Subsequently, the analysis also focuses on various features such as PV capacity and inverter topology, and it also analyses the renewable grid source that are exploited in each paper. Furthermore, this paper provides the detailed study regarding the chronological review and performance achievements in each contribution. Finally, it extends the various research issues which can be useful for the researchers to accomplish further research on PV-based MG systems.

This paper has presented a detailed review on PV-based MG systems that were enumerated in the above sections. Here, various controllers along with their better achievements were analyzed and described. From the review, it was known that several PV-based MG systems were really at the point for enabling better power output and conversion efficiency. In conclusion, this paper reviewed about 65 research papers and declared the significant analysis. Initially, the analysis also focused on various controller classifications in PV-based MG systems that were reviewed in this paper. Subsequently, the analysis also focused on various features, such as PV capacity and inverter topology. The analysis also reviewed the performance achievements and renewable gird source that were exploited in PV-based MG systems. At last, this paper has presented various research issues which can be useful for the researchers to accomplish further research on the features of PV-based MG systems.

This paper presents a brief analysis of PV-based MG systems. This is the first work that uses PV-based MG systems for better regulation of MPPT.

Effective cooling is one of the challenges for photovoltaic thermal (PVT) systems to maintain the PV operating temperature. One of the best ways to enhance rate of heat transfer of the PVT system is using advanced working fluids such as nanofluids. The purpose of this research is to develop a numerical model for designing different form of thermal collector systems with different materials. It is concluded that PVT system operated by nanofluid is more effective than water-based PVT system.

In this research, a three-dimensional numerical model of PVT with new baffle-based thermal collector system has been developed and solved using finite element method-based COMSOL Multyphysics software. Water-based different nanofluids (Ag, Cu, Al, etc.), various solid volume fractions up to 3 per cent and variation of inlet temperature (20-40°C) have been applied to obtain high thermal efficiency of this system.

The numerical results show that increasing solid volume fraction increases the thermal performance of PVT system operated by nanofluids, and optimum solid concentration is 2 per cent. The thermal efficiency is enhanced approximately by 7.49, 7.08 and 4.97 per cent for PVT system operated by water/Ag, water/Cu and water/Al nanofluids, respectively, compared to water. The extracted thermal energy from the PVT system decreases by 53.13, 52.69, 42.37 and 38.99 W for water, water/Al, water/Cu and water/Ag nanofluids, respectively, due to each 1°C increase in inlet temperature. The heat transfer rate from heat exchanger to cooling fluid enhances by about 18.43, 27.45 and 31.37 per cent for the PVT system operated by water/Al, water/Cu, water/Ag, respectively, compared to water.

This study is original and is not being considered for publication elsewhere. This is also not currently under review with any other journal.

A cascaded observer-based transfer delay frequency locked loop (CODFLL) algorithm is developed to control the distribution static compensator (DSTATCOM) to address various power quality (PQ) issues arise because of distorted grid and load conditions. Moreover, frequency locked loop is included along with the observer to take care of the frequency drift from nominal value and to improve its performance during steady state and transient conditions. During daylight, the proposed system works as photovoltaic (PV) DSTATCOM and performs multiple functions for improving PQ whilst transferring power to grid and load. The system under consideration acts as DSTATCOM during night and bad weather condition to nullify the PQ issues.

CODFLL control algorithm generates reference signal for hysteresis controller. This reference signal is compared with an actual grid signal and a gate pulse is produced for a voltage source converter. The system is made frequency adaptive by transfer delay adaptive frequency locked loop (FLL). Peak power is extracted from a PV source using the perturb and observe technique irrespective of disturbances encountered in the system.

The PV system’s performance with the proposed controller is studied and compared with conventional control algorithms such as least mean fourth (LMF), improved second-order generalized integrator frequency locked loop (ISOGI-FLL), synchronous reference frame phased lock loop (SRF-PLL) and frequency adaptive disturbance observer (DOB) for different cases, for example, steady-state condition, dynamic condition, variable insolation, voltage sag and swell and frequency wandering in the supply side. It is found that the proposed method tracks the frequency variation faster as compared to ISOGI-FLL without any oscillations. During unbalanced loading conditions, CODFLL exhibits zero oscillations. Harmonics in system parameters are reduced to the level of IEEE standard; unity power factor is maintained at the grid side; hassle-free power flow takes place from the source to the grid and load; and consistent voltage profile is maintained at the coupling point.

CODFLL control algorithm is developed for PV-DSTATCOM systems to generate a reference grid current.

The purpose of this paper is to present a critical review of the key trends in the integration of photovoltaic (PV) facilities into the built environment in cities. This is regarded as part of a series of measures towards wider use of renewable energy sources.

The problem has been approached from the point that cities are consumers of large amounts of energy. They require uninterrupted energy supply but with dynamic power profile. Mainly consumption of energy generated from fossil fuels is present nowadays with significant pollution of the environment as a consequence. The sustainable energy transition in cities means increasing the supply of energy from renewable sources.

The paper points to the integration of PV renewable systems in the built environment, opportunities and constraints, design conditions and tools. The consideration of the constraints which creates urban environment is carried out to understand the complexity of selecting locations in the cities. The paper gives an overview of the possibilities of PV systems integration in the built environment and discusses physical limitations in the urban environment and simulation tools as well as challenges and research and development issues.

The paper offers a critical review of the PV applications which have been illustrated with examples from developed countries. However, examples from developing markets have not been considered. Future work would address this limitation and enable the discussion from a comparative perspective.

The study gives a comprehensive overview of PV integrations in contemporary cities, stimulating architects’ practitioners to acquire the PV technology and aesthetics, and to apply it in future developments.

Observing the use of PV applications from the perspective of architects and designers the discussion and examples covered in this paper offers an original review, which provides the base future in-depth studies on PV applications in various contexts.

This paper aims to develop a selective energy optimisation of the photovoltaic–thermal (PV/T) system performance. The PV cell inside the PV/T system could be periodically manipulated to produce domestic hot water without applying an external power supply.

A numerical simulation model of the proposed PV/T model was developed in MATLAB/Simulink to analyse the selective energy optimisation of the model. The extrinsic cell resistance (R_se) is adjusted to control the ratio of thermal to the electrical energy, generated from the PV cell inside the PV/T system. Therefore, the internal heat of the PV cell inside the PV/T system is periodically used as a thermal element to produce electrical power and hot water.

The optimisation of PV/T energy shows that the electrical power efficiency can increase by 11.6% when R_se was 0 Ω, and the 200 L water tank temperature increased by 22ºC when R_se was 50 Ω.

This study showed that the use of the PV cell could be extended to domestic hot water and space heating, and not only for electricity.

This paper aims to propose an integrated protection scheme for converters of a low-power, low-cost photovoltaic system. Power electronic converters use a variety of methods to limit overload and fault current. The use of insulated and non-insulated sensors along with additional circuits to detect and limit fault current can cause current to be limited or completely cut off before damage to semiconductor devices. In addition, fuses that have slower performance are used as backup for any type of protection.

First, all the candidate points for protection are investigated. In this paper, after examining the performance of glass fuses as linear resistors, they are used as a current feedback element. A simple, isolated and reliable circuit for fault detection at various points of the system has been proposed that can be implemented and operated in single shot or auto-reclose operating mode.

The experimental results of this circuit on a dc/dc converter and an H-bridge inverter show that it can cut off all instantaneous short circuit errors in less than 50 µs and prevent damage to the semiconductor switch.

In low-cost and low-power converters, it is usually not cost-effective to use complex and expensive devices. For this reason, these converters are more vulnerable to faults. On the other hand, in complex systems such as photovoltaics, several converters are used simultaneously in different parts, and the occurrence of a fault in each of them causes the whole system to fail.