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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.

The roofs of houses located at middle latitudes receive significant solar radiation useful to supply their own energy demands and to feed back into the urban electricity network. However, solar panels should be properly integrated into roofs. This study analyzed roof geometry and integrated solar performance of Photovoltaic, thermal-photovoltaic, and hybrid solar collection technologies on dwelling cases selected from a sample of recent housing developments in Concepción, Chile. Hour-by-hour energy generation estimates and comparisons with demand levels were calculated for representative days during seasons of maximum, minimum as well as mid-season. These estimates took into account the roof tilt and orientation effects also. Trnsys@ software was used to determine electricity supply and F-Chart tool for thermal energy supply. The results show five times more panels can be placed on the largest and most regular shaped roof sections than on those with the smallest and most irregular shapes. The house model with the largest roof section can provide up to six times more energy than the model with the smallest second roof section in different seasons and systems. This paper thus provides new findings on the performance of solar technologies when related to home energy demands and roof geometry.

Priorities of decarbonizing the mining sector together with an availability of cost-effective technological solutions lead renewable energy (RE) to become an attractive energy source for the mining industry. Several pilot projects are run as hybrid systems, providing additional capacity to traditional energy systems. The purpose of this paper is to develop a mathematical model as a decision-making tool. The decision refers to a replacement of the fossil fuel system contains by the hybrid system in the sense of no return.

Four systems are considered. System one contains only a diesel plant. System two consists of a hybrid energy system with a photovoltaic (PV) part and a genset as back-up. System three includes a conventional natural gas combined cycle (CGCC) plant. Finally, system four covers a hybrid energy system with a PV part and CGCC turbine. The mathematical model is based upon the well-known concept of levelized cost of electricity.

The scenarios account for the degradation rate of PV modules, the PV yields of mines in different locations and the greenhouse gas emissions impact. The results show the break-even times of each scenario and the years of no return for the four systems in each scenario.

The solution of the model is performed for two case-studies. Case study 1 compares the diesel and hybrid PV-diesel systems. Case study 2 compares the CGCC and hybrid PV-natural gas systems.

This model can be generalized to all mining settings, with specific practical implications for off-grid mines.

The results of this paper bring a valuable contribution to carbon dioxide emissions reduction.

The paper aims to enhance the attention of decision-makers on fossil fuel and RE technologies increase the attractiveness of RE in powering mining operations.

The important factors, which should be considered in the design of a hybrid system of photovoltaic and wind energy are discussed in this study. The current load demand for electricity, as well as the load profile of solar radiation and wind power of the specified region chosen in Iran, is the basis of design and optimization in this study. Hybrid optimization model for electric renewable (HOMER) software was used to simulate and optimize hybrid energy system technically and economically.

HOMER software was used to simulate and optimize hybrid energy system technically and economically.

The maximum radiation intensity for the study area is 7.95 kwh/m²/day for July and the maximum wind speed for the study area is 11.02 m/s for January.

This research is the result of the original studies.

This study aims to analyze the effects of variations in annual real interest rates in the assessment of the techno-economic feasibility of a hybrid renewable energy system (HRES) for an off-grid community.

Hybrid Optimization of Multiple Energy Resources (HOMER) software is used to propose an HRES for Abadam community in northern Nigeria. The HRES was designed to meet the basic needs of the community over a 25-year project lifespan. Based on the available energy resources in the community, photovoltaic (PV), wind turbine, diesel generator and battery were suggested for integration to serve the load requirements.

When the annual real interest rates were taken as 10 and 8 per cent, the total amount of total energy fraction from PV, wind turbine and the diesel generator is 28, 57 and 15 per cent, respectively. At these interest rates, wind turbines contributed more energy across all months than other energy resources. The energy resource distribution for 0, 2,4 and 6 per cent annual real interest rates have a similar pattern, but PV contributed a majority of the energy.

This study has used annual real interest and inflation rates dynamic behavior to determine optimal HRES for remote communities. Hence, its analysis will equip decision-makers with the necessary information for accurate planning.

The results of this study can be used to plan and design HRES infrastructure for off-grid communities around the world.

“the purpose of this study/paper” or “this study/paper aims to” in the Purpose section of the Abstract. The integration of distributed generation (DG) to the utility grid is yet another approach to provide reliable and secured power.

The significant concern in this contemporary world are the day-to-day increasing power demand, lack of energy and increasing environmental pollution, which are threatening the existence of living things.

The research focus here is to adequacy and security in the grid-integrated hybrid distributed generation (DG) having photovoltaic (PV) and proton exchange membrane fuel cell.

PV system is a clean source of generation and suitable for many applications. Photovoltaic cell captures the energy from solar irradiation. To track the maximum power from PV, perturb and observe method is used. As it is intermittent in nature, integrating PV with fuel cell makes the hybrid source more reliable. Power electronic interfacing devices are used to integrate this hybrid DG source to microgrid. The simulation of this grid-connected hybrid DG is performed using Matlab/Simulink environment.

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.

Nanotechnology has developed gradually in recent years and it is encountered in various applications. It has many usage area especially in energy systems. The purpose of this study, in a photovoltaic thermal system, thermal behaviours of a PV panel has been investigated by energy and exergy analysis method using a phase change material inserted 5 per cent weighted Al₂O₃ nanoparticle.

In this study, one of the three different PV panels was kept normally, the other one was filled with a phase changing material (paraffin-wax) and the last panel was filled with the mixture of a nanoparticle and paraffin-wax.

After the analyses, especially during the time intervals when the radiation is high, it is found that the panel with Np-paraffin mixture has a high electrical and thermal efficiency. In addition, as a result of the exergy analyses, average exergy efficiency of the panel with Np-paraffin mixture has been determined as 10 per cent, whereas that of the panel with paraffin as 9.2 per cent.

Nanoparticles had not been used with PCMs in photovoltaic–thermal systems in the studies made before.

The purpose of this paper is to design and implement a directly cooled photovoltaic thermal (PV/T) hybrid system.

The research design subjects, instruments and methods that were used to collect data are as detailed in the paper. Two polycrystalline photovoltaic (PV) modules were used in this study.

The directly water-cooled PV module (PV/T) was found to operate better as compared to a naturally cooled module for the first three months. The PV/T initially operated at a higher electrical efficiency for 87 per cent of the day. The monthly energy-saving efficiency of the PV/T was found to be approximately 61 per cent, while the solar utilisation of the naturally cooled PV module M1 was found to be 8.79 per cent and that of M2 was 47.93 per cent.

The major limitation was the continued drop in efficiency after the first three months of the PV/T placed outdoors. The fall in the efficiency was attributed to water ingress.

Direct water cooling of PV modules is possible, only that a better sealing is needed to prevent water ingress.

PV air cooling has been researched on. Use of water as a cooling medium has been carried out using serpentine pipes or riser tube, and no direct water cooling on the back of the module has been researched on.

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.