In this manuscript, a solar cavity packed with the thermoelectric generator modules has been investigated numerically. The hot plate of TEG modules makes the inner surface of the cube, and the cold plate is the outside the cavity, under natural convection. The TEG modules are electrically in series. The solution algorithm using the equations of heat transfer and generated power of TEG modules is developed via MATLAB and simulated under various non-concentrated irradiation levels. The variation of generated power in solar thermoelectric cavity shows that increasing of the solar irradiance caused increasing the growing rate of the generated power. The radiation varies from 700 to 1200 W/m2, and the generated power is increased from 0. 26 mW to 10 mW in the side of TEGs and up to 30 mW in the bottom of TEGs. The evaluation of aperture size indicates although the generated power of fully open cavity is 2. 25 times higher than the generated power in 0. 05×0. 05 m2 aperture size cavity, its efficiency is 46% lower than the small aperture cavity. Heat transfer analysis of cavity depicts that 91% of heat transferred by conduction in the cube surfaces. Only 6% and 3% of input energy are lost by re-radiation and convection through the aperture, respectively.

Using renewable energy is an efficient method for addressing the drawbacks of utilizing fossil fuels. The study focuses on a multigeneration system that integrates PTC solar collector and geothermal energy, along with two ORC cycles, a single-effect absorption refrigeration cycle, a PEM electrolyzer, and a dryer. A TEG unit is utilized in the ORC cycles to increase power production. The system is analyzed from energy, exergy, and exergoeconomic perspectives using EES software. Parametric analysis is conducted to assess the impact of crucial parameters on the system's performance. The examination of overall results reveals that the energetic and exergetic efficiencies of the multigeneration system are 41.58 and 25.61%, respectively. The power generated by ORC1 turbine and ORC2 turbine are 461.9kW and 227.6kW, respectively. Introducing TEG units in place of condensers in the ORC cycles results in increased power production to 138.2kW and 328.2kW for ORC1 and ORC2 cycles. The energetic and exergetic COPs of the system are 0.8103 and 0.3484, respectively. Additionally, the multigeneration system is capable of producing 493.1 kg/day of hydrogen. Lastly, six different working fluids in the ORC cycle were investigated. It is demonstrated that among the 6 working fluids, n-pentane exhibited the best performance.

Gaining solar energy by the valence electrons of the dye molecules is the first motive force to rule a dye-sensitized solar cell (DSC). This admits the importance of the dye molecule and its features, from the electronic states till the absorbance and the functional groups, to anchor to the nanostructured semiconductor photoanode, attain solar energy and finally convert it into electricity. To this purpose, the current study introduces cyanocobalamin (B12 vitamin) to play this role in DSCs. From one side, density functional theory (DFT) reveals the energy of the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO), and the bandgap of B12 vitamin as-7. 4,-4. 9, and 2. 5 eV, respectively. On the other side, the experimental ultraviolet-visible (UV-Vis) spectroscopy on B12 solution represents its broad absorption spectrum in this region. These results show that the proposing dye perfectly matches the electronic domino of the DSC device. Furthermore, this study discloses the matching semiconductors, redox shuttles, and counter electrodes (CEs) to construct B12-vitaminized dye-sensitized solar cells.

Experiments were carried out for the numerical investigation of heat transfer enhancement in a solar air collector using different types of baffles and vortex generators. In this study, the vortex generator was implemented to increase the efficiency of the solar air collector. The variations in Nusselt number, pressure drop, friction coefficient, and thermal and exergy efficiency in four collectors with different baffles arrangement (type A, B, C, D) were investigated. Type A was chosen as the optimum collector for implementing the vortex generator on the absorber surface. In the solar air collector the effects of using a novel vortex generator-the Perforated Delta Wing Vortex Generator (PDWVG), in comparison with a flat one-the Flat Delta Wing Vortex Generator (FDWVG), were considered. In order to determine the maximum efficiency of the solar air collector, four different pitch ratios of vortex generators were studied. The Nusselt number and pressure drop increased with the Reynolds number but the friction coefficient decreased with Reynolds, the experimental and numerical results revealed that the thermal and exergy efficiency decreased from a specific range. The comparison of PDWVG and FDWVG showed that the presence of holes on the novel vortex generator led to reduced pressure drop and increased heat transfer between the airflow and the absorber surface. Increasing the number of vortex generator rows had a slight effect on increasing the studied parameters. The results showed that collector type A with ep=0. 55 of PDWVG improves the energy and exergy efficiency 4. 43% and 5. 29% respectively.

The present study discusses the effects of apping exible vortex generators on two-dimensional turbulent free convection air ow in a double-pass solar air heater. To this end, two thin elastic winglets used as vortex generators were attached to two absorber walls near the inlet section at an attack angle of 65, C. This novel concept was elaborated through transient numerical simulation of the ow , eld based on the , nite element method and uid-solid interaction. In addition, an extensive comparison of four di, erent con, gurations was made in this study. The absorber and outlet temperatures as well as the ow rate and velocity , eld were carefully calculated, numerical results of which con, rmed the considerable enhancement of thermal performance compared to that of conventional parallel double pass heater. The improvement rate was up to 54% in the case of delta T-= Tout-Tin from 13 to 20oC while reducing the flow rate by 33. 6%. The present numerical results were validated based on the experimental and numerical data reported in the literature.

The future power system, with the unprecedented penetration of renewable energy resources, will be faced with many uncertainties which may lead to problems in grid operation. Consequently, the uncertainty assessment of system performance is essential. Hence, the conventional power flow methods, given the constraints of the electricity and gas networks, may not be suitable for distribution networks such as the multi-carrier microgrids. This paper presents an effective method for optimizing the simultaneous utilization of different energy infrastructures in an environment with different uncertainties considering the constraints of the network. The aim is to study the effect of uncertainties on the optimal operation management of an interconnected microgrids. The fluctuation behavior of loads, renewable resources, and electricity price has been investigated in the proposed model based on probabilistic power flow technique. The results of the system are extracted as random variables, which are depicted in probabilistic and cumulative distribution forms. In this study, the multi-carrier microgrids not only exchange energy with the main grid, but also, energy interchange among the microgrids is possible. Simulations are presented, applying the procedure to an illustrative system of three interconnected MCMGs, and the results justify the effectiveness of the proposed technique.

The main challenge in establishing communication with mobile wireless communication systems in inaccessible areas is to use a suitable energy source, which is very important for users on long-term missions. In this study, the usage of solar cells based on perovskite layers is investigated to improve the performance and efficiency of solar cells in solar chargers of wireless mobile communication systems.It is obvious that the optical properties indicate a high absorption index of these samples at orders of 104 cm-1 .The band gap energy values of the samples show a decreasing trend with increasing the thickness of the perovskite layer. The I-V characterization of the studied solar cells showed that with increasing the thickness of perovskite layers, the efficiency of the cells increases, and this efficiency is higher than the cases reported in previous studies. The constructed cells are also highly stable, and may be used in impassable places and mountainous areas for proper charging of mobile wireless communication systems.

The main challenge in establishing communication with mobile wireless communication systems in inaccessible areas is to use a suitable energy source, which is very important for users on long-term missions. In this study, the usage of solar cells based on perovskite layers is investigated to improve the performance and efficiency of solar cells in solar chargers of wireless mobile communication systems. It is obvious that the optical properties indicate a high absorption index of these samples at orders of 104 cm-1. The band gap energy values of the samples show a decreasing trend with increasing the thickness of the perovskite layer. The I-V characterization of the studied solar cells showed that with increasing the thickness of perovskite layers, the efficiency of the cells increases, and this efficiency is higher than the cases reported in previous studies. The constructed cells are also highly stable, and may be used in impassable places and mountainous areas for proper charging of mobile wireless communication systems.