Application of renewable energy sources has shown a perfect potential as a form of contribution to conventional power generation systems. This paper presents a hybrid system based on photovoltaic (PV) module and PEM (proton exchange membrane) fuel cell (FC) with the aim of selling electricity to distribution network (DN) and improving its reliability. In this paper, moreover supplying the load electricity of system, the proposed hybrid system is capable to sale electricity to DN and by electricity injection causes DN reliability improvement. The revenue from selling electricity to DN is considered as the system profit (SP). An optimization is applied to maximize the SP using GAMS environment. This study claims that moreover load electricity provision, electricity can also be sold to DN by proposed hybrid system and reliability of DN in load supplement can be increased by injecting the electricity to it.

Buildings represent the largest energy-consuming sector; thus, exploring methods to decrease energy consumption within them is of utmost importance. Two energy-generating solutions within buildings are rooftop photovoltaic (PV) systems and PV windows. Additionally, incorporating Phase Change Materials (PCM) into building walls presents an energy-saving solution. This research compares the reduction of energy consumption through PCM with electricity generation via rooftop PV systems and PV windows. Results indicate that reductions in electricity consumption for rooftop PV, PV windows, and PCM are 11.5%, 1.4%, and 2.1%, respectively. Furthermore, an economic analysis was conducted on the energy produced by the photovoltaic power plant for sale to Iran’s Ministry of Energy. Findings reveal that under the condition of selling electricity, the payback period for a rooftop PV system is 6.3 years.

This study shows the design of a new hybrid power generation system, photovoltaic panel (PV)-coupled solid oxide fuel cell (SOFC) and gas turbine (GT)-electrolyser. Three objectives (cost, pollutant emissions, and reliability), which are usually in conflict, are considered simultaneously. The design of a hybrid system, considering the three mentioned objectives, poses a very complex problem of optimization. A multi-objective optimization method (PESA) is considered to obtain the best combinations for the hybrid system. In this work, the effect of panel's angle change and SOFC-GT fuel type are considered too. In order to study the effect of fuel price, this study is done about two fuel prices: Iran fuel price and international fuel price.

In Iran, pressurized irrigation systems is increasing. One of the requirements of pressurized irrigation systems is to supply energy to pump water. Because of non-renewal, extraction costs and environmental hazards of fossil fuels, solar energy utilization has become inevitable. Solar energy is one of the most important and cleanest forms of new energies which can return the initial cost of solar system to a customer in the long term. One of the reasons for Iran's failure to use a large part of its cultivated land is a large distance from the national electricity network and high electricity costs. In this study, solar and electric pumps were compared economically to pump water in nine gardens under drip irrigation networks including three crops: pistachio, almond, and walnut. The gardens are located in two provinces of Tehran and Hamedan. The drip irrigation system is applied in these gardens. The gardens were classified into three groups: small (less than 5 hectares), medium (5 to 60 hectares) and large (more than 60 hectares). First of all, pumping station was designed and then investment costs were estimated for all the studied gardens. To design and simulate photovoltaic system, the Lorentz solar pump special design software was used. It is assumed that electricity would supply for these areas in two ways including 1) installation of photovoltaic systems in remote areas without a national electricity grid 2) electricity transmission through the construction of transmission lines and trans-installation. These two conditions were compared by the present value method at two interest rates, 5 and 10%. To convert future costs to present value, real interest rate index is required. Considering the difference between the useful life of equipment for electric pumps and solar pumps, as well as solar panels, the lifetime of the projects was considered unequal in calculating the current value. The results showed that the utilizing photovoltaic pumping without distances from the electricity distribution network is only economic in 60 ha pistachio garden with an interest rate of 10%. In the walnut garden with medium size, with the same interest rate, despite the slight difference in investment cost, it is not different with electric pumping. In the case of distance from the power distribution network, photovoltaic pumping will be more economical by reducing farm size (less capacity and pressure) and increasing the distance from the power distribution network. Of course, other factors such as temperature, sunshine, radiation intensity and solar angles may also affect photovoltaic pumping during different seasons. The results also showed photovoltaic pumping of irrigation system is economic for small and medium pistachio and walnut gardens, at 0. 5 kilometres of the electric distribution network, in the interest rate of 5% and 10%. With increasing distance from the electricity distribution network, only the cost of transferring power lines to electric pumping costs increase and the use of photovoltaic pumping is more justifiable. Changes in the current value of costs for both pumping methods at a rate of 10% relative to the 5% interest rate will lead to cost reductions. In remote areas, which it is difficult to access to electricity distribution and transmission networks, the use of photovoltaic pumping is reasonable and economical. For each area, there is a specific distance from the electric distribution network which photovoltaic pumping is reasonable for drip irrigation.

This paper describes a DC isolated network which is fed with Distributed Generation (DG) from photovoltaic (PV) renewable sources for supplying unbalanced AC loads. The battery energy storage bank has been connected to the DC network via DCIDC converter to control the voltage of the network and optimize the operation of the PV generation units. The PV arrays are connected to the DC network via its own DC/DC converter to ensure the required power flow. The unbalanced AC loads are connected to the DC network via its own DCIAC converter. This paper proposes a novel control strategy for storage converter which has a DC voltage droop regulator. Also a novel control system based on Park rotating frame has been proposed for DCIAC converters. In this paper, the proposed operation method is demonstrated by simulation of power transfer between PV arrays, unbalanced AC loads and battery unit. The simulation results based on PSCAD/EMTDC software show that DC isolated distribution system including PV generation systems can provide the high power quality to supplying unbalanced AC loads.

Photovoltaic/thermal (PV/T) is a solution for solar energy conversion devices to increase their efficiency. One of the challenges of PV/T is maintaining the temperature at optimal working conditions. Various studies have been conducted to improve PV/T performance, one of which is through the design of thermal collectors on PV/T. In this study, Computational Fluid Dynamics (CFD) simulations were conducted using four different types of channels: circular, hexagonal, semi-circular, and square. The channels were made with the same tube cross-sectional area and mass flow rate of 0.0016 m2 and 0.0096 kg/s, respectively. The simulation results show that the circular channel numerically gives the lowest PV cell temperature, 317.95 K, with an electrical efficiency of 14.70% and a thermal efficiency of 44.18%. This is because the water velocity in the circular channel can be faster than the other channels.  The circular channel has a thinner boundary layer, so the velocity is maximized, and the heat transfer rate increases.

The paper aims to develop a setup for the experimental validation of simulation models of an off-grid, renewable-based integrated energy system that combines wind and solar energy with lead-acid battery storage. This setup and model offer an opportunity to investigate the effects of climate conditions and technology on energy flow within the supply system. The case study is based on the climatic conditions of Tehran, Iran. To simulate wind speed conditions, a wind tunnel was developed for testing the wind turbine. Photovoltaic panels were installed outdoors and exposed to natural solar irradiation. The system’s performance was evaluated through both simulation and experimental measurements under identical conditions. The simulation and experimental results showed strong agreement, with power output errors of 4.8% for the wind turbine, 6.5% for the photovoltaic panels, and a 6.2% relative difference for the total hybrid system over several hours. These findings confirm the model’s accuracy and its potential for guiding the design and optimization of renewable hybrid energy systems.

The addition of renewable energy sources to the traditional distribution network has transformed the centralized unidirectional power source into two-way and multiple power source system. This will improve overall system's reliability and also reduces the down time that are associated within the radial distribution system. This paper investigates the impact of distributed energy sources like PV, Wind, Electric Storage, and Gas Turbine Generator on the reliability of distribution system. The Monte Carlo simulation method is used to test bus-2 of IEEE RBTS distribution network. The distribution network has been customized to incorporate the WT, PV, ESS, and GTG distributed generation. The WT and PV stochastic models were employed to replicate the unpredictability of these sources since speed of wind and solar radiation are both unpredictable. This work shows that the integration of distributed generation enhances the distribution system's reliability.