This paper investigates the uses of solar energy systems in various applications to define the most appropriate system that has highly efficient and reliable. Most of the urban even rural areas that suffer from lack of continuous power supplies it prefer to depend on hybrid systems like solar/wind systems, solar/geothermal system and solar/diesel-battery systems. Investigation indicates that hybrid systems could meet the required loads in different proportions depending on the operating conditions and components of the hybrid system compare with the separate system but has complexity regarding their components of the system with the high initial cost Moreover, Utilize hybrid solar/thermal system is more sufficient than had systems that mentioned as a result of the improvements at his parts to increase the overall efficiency by use PCM, nanofluid or a mix of PCM - nanofluid as cooling the PV panel to keep the efficiency of the solar cells and increase thermal energy. Thus, hybrid solar/thermal systems had proven effective to meet the required loads of electric energy and good capacity to provide thermal energy simultaneously without toxic emissions with a negligible complexity of its components.

The photovoltaic module (PV) consists of many photovoltaic cells made of silicon that lose their properties with an increased temperature. Increasing photovoltaic cell temperature represents an intrinsic problem that causes a drop in the open-circuit voltage of the PV module, thus affecting its performance. The present work investigates using evaporating cooling as a passive cooling technique to absorb the generated heat from the PV module and lower its temperature by cotton wicks immersed in the water (CWIWs) attached to the backside photovoltaic module. The CWIWs decrease air dry temperature and increase humidity and then produce cool air to help cool PV modules. The results showed dropped PV module temperature by about 22% attributed to providing appropriate cooling produced by the moist condition of the cotton bristles immersed by water exposed to the wind. The output power generation and efficiency have increment by 16.3 W and 53%, respectively. The electrical exergy was equivalent to output power under the evaporating cooling, while entropy generation dropped about 14% with increased the PV module temperature.

Vehicle engine cooling systems have several functions. Excess heat removal from the engine helps to rapidly cool it, quickly reach operating temperature, maintain a constant engine operating temperature, and provide heat to the vehicle’s passenger compartment. Developments in the automotive industry, such as hybrid and electric vehicles, now also involve the temperature management of battery packs. Currently, the coolant used in cooling systems is water or an equivalent substance. Water as a coolant has low thermal conductivity. Therefore, researchers are trying to use nano-liquid as a coolant in the cooling system. Better results are expected by use of this alternative. Nano-liquids contain metal particles that enhance thermal transfer properties, so current and future cooling systems could operate more efficiently. Adding phase change materials to the cooling and air handling systems will result in better efficiency in future vehicles. In the case of hybrid and electric vehicles, the addition of thermoelectric generators to cooling and exhaust systems increase efficiency. Present developments help increase a vehicles’ usability and the possibility of achieving greater efficiency.

Three strategies are used in this paper to investigate suspension systems behaviour. Firstly, the steel coil passive spring (conventional spring) is replaced by air spring, which comprised of an airbag, a connection pipe with a control valve, and a reservoir tank system. The influence of air spring pressure, reservoir volume and connection pipe diameter on suspension system behaviour are investigated. Secondly, a logic control scenario for the oscillation mass of air between spring airbag and the reservoir is applied by using on/off valve controller to study the controlling valve influence on the whole vehicle dynamics responses. Thirdly, the MR damper is used to introduce a variable damping coefficient as a semi-active control (skyhook) strategy of the suspension system. To represent the suspension system with the earlier mentioned strategies, a mathematical model 2-DOF for a quarter car is adopted along with governing equations of the air spring and semi-active skyhook control under the Matlab/Simulink platform. The obtained result, i.e., suspension travel displacement, body acceleration, dynamic tire force, and damper dissipation energy, are calculated in terms of RMS to show up the dynamic behaviour of suspension system considering four configurations in various control styles. The models’ responses were examined versus two road excitations pattern, including harmonic excitation and random road excitation. The results show that using air spring is considerably increased suspension quality, furthered more the suspension system is significantly enhanced when semi-active strategies are applied on air spring and MR damper.

Overcoming the issue of photovoltaic (PV) module productivity at high temperatures is one of the most critical obstacles facing its use. PV cells are made of silicon, which loses its properties at high temperatures, degrading the PV module work. The present research compares cotton wicks integrated with rectangular aluminium fins (CWIRAFs) submerged in water as passive cooling with an absorbing plate and copper pipes attached at the PV module backside as active cooling. Compared with the PV module without cooling, CWIRAFs have better performance with the PV module than active cooling owing to evaporative cooling and increased heat dissipation area represented by wet cotton bristles integrated. The PV module is exposed to significant performance degradation without cooling in hot climate conditions. As a result, using CWIRAFs with the PV module had reduced the temperature by 31.4%, increased the power by up to 66.6%, and increased the electrical efficiency from 3.12 to 8.6%. Active cooling methods have reduced the PV temperature by 20.8%, increased the power by 56.7%, and enhanced electrical efficiency by 7.9%. Removing excess heat from the backside of the PV module via circulating water has improved the thermal efficiency and overall efficiency of the PVT system by about 26.3 and 34.2%, respectively.

This paper appears potential of use nanofluids as a working fluid with the photovoltaic/thermal (PV/T) systems as an alternative of the conventional liquids in improves the efficiency of the hybrid PV/T system. The review highlights the impact of some parameters (base fluid, volume fraction, the concentration of nanoparticles, surfactants, shape, and size of nanoparticles) on nanofluids' thermophysical properties and their effect on the PV/T system's efficiencies. Hence, it discusses the PV/T behavior, which uses different nanofluids based on previous experimental, analytical, and numerical studies. The review concluded that using nanofluid as a cooling fluid or spectral filter contributes by enhancing the performance and increasing the PV/T system's efficiency. Thus, each type of nanofluids has certain features that contribute to removing the PV cells' excess heat by cooling it, contributing to its work's stability, and increasing its productivity. Nanofluids thermophysical properties play an intrinsic role by enhancing nanofluids' performance, thus positively reflecting on the PV/T system's performance. Despite the variation in the values of thermal and electrical efficiency, Most of the studies that used nanofluids have achieved encouraging results that appeared by improving the performance of PV/T systems.

Today, the increasing use of solar energy contributes to the EU's energy policies. Increasing use of renewable energy sources reduces pollutant emissions, dependence on fossil fuels and improves air quality. Globally, installed photovoltaic capacity has reached 400 GW by the end of 2017, and is projected to reach 4,500 GW by 2050. In the context of this research, we would like to present a detailed presentation of the possibilities and effects of integrating solar systems into electricity networks. The integration of renewable energies into networks is of paramount importance to researchers because of current energy demand and the depletion of fossil fuel reserves and environmental impacts. In this study, we highlight the effects of solar network integration on both the solar system and the public utility service. We also report on the opportunities and impacts of integration in Hungary in connection with our research. Today, solar panels are the cornerstone of sustainable development.

Growing global energy demand has become worrying due to the fluctuating fossil fuel prices, the damage caused by the use of conventional fuels as the toxic emissions and global warming. Therefore, dependence on alternative and sustainable sources has become a pressing topic. In this paper will review the performance of solar chimney power plant, the parameters that affect on the performance, conversion efficiency and power output for a different collection of prototypes. During this study there are found that power output of the solar chimney power plant is directly proportional to increase of the height of the chimney, specifically when the solar chimney is sloped where the performances is better as well as the conversion efficiency. While increasing the diameter of collector will provide a big heating area which cause a decrease of air density due to rise in the air temperature under the solar collector which lead to increase the flow of driving force and the mass flow rate that causes an increase in the power output. Pressure drop is an important factor for identifying the maximum power output when the solar radiation is a constant which effect on thermodynamic properties. Therefore, the efficiency will increase with increasing the optimal proportion of pressure drop.