Nowadays, the world is encountering multiple challenges of energy security, economic recovery, and the effect of global warming. Investing in new fossil fuels only locks in uneconomic practices, sustains existing risks and increases the threats of climate change. In contrast, renewable energies, such as photovoltaic energy, constitute one of the most promising technologies in combating global increase in temperatures. Given its simplicity and low maintenance costs, photovoltaic energy is the most effective alternative to address the issues above. However, the standard test conditions (STCs) of PV modules are, in most cases, different from the real working conditions of a solar module. For instance, high levels of incident irradiation in an arid climate may cause the temperature of a module to rise by many degrees above the STC temperature of 25 °C, lowering the module’s performance. To effectively simulate and control PV systems for a given location, it has become paramount to develop a robust and accurate model that considers how PV modules behave. This study seeks to introduce an emerging metaheuristic optimization algorithm to estimate the unknown parameters of PV modules. The strategies deployed by flying foxes in the event of high temperatures have given birth to the development of a new metaheuristic algorithm called FFO. Contrary to previous methods, this new modeling procedure makes it possible to calculate all the parameters, regardless of temperature or irradiance. Four PV modules, having different technologies, were tested to evaluate the accuracy of the algorithm in question. The effectiveness of FFO is then contrasted with other well-known metaheuristics where single and double diode models are deployed. The results show that the FFO optimizer represents a substantial and compelling substitute for PV module extraction methods.

Using molecular dynamics simulations based on the embedded atom method, we present the calculations of adsorption and activation energies for the diffusion of adatoms (Cu, Ag or Au) on Cu (100), Ag (100) or Au (100) surfaces with steps. We have also examined the relaxation trends and bond lengths of the adatoms for both fourfold and bridge sites. We note that the vertical distance of the adatom relaxation to the first nearest neighbors is the largest (1.56 %) for Ag on Cu (100) and the shortest (–14.58 %) for Cu on Au (100) as compared to other systems. On the other hand, for Cu on the Au (100) system, we find the adatom barrier for hopping along the step edges to be 0.44 eV, which is the highest for this process among the systems studied here, but the lowest barrier is found for Ag on Cu (100) compared to other systems and costs only 0.20 eV. Attention has also been focused on the evaluations of the adsorption and activation energies for the nine systems in the presence of step edges. The diffusion barriers over and along step edges are interpreted in terms of the cohesive energies of the adatoms and substrates. Moreover, these results can offer some basic rules for forecasting precise atomic surface morphologies in homo- and hetero-epitaxial growth.

With the possibility of harvesting the coldness of the atmosphere as an inexhaustible thermodynamic resource, passive radiative cooling technology is used for many applications such as refrigeration, renewable energy harvesting and dew condensation. However, in this study, we focus on dew harvesting as a new-researched area. This paper presents an energy balance modelling approach to predict the nightly water yield from meteorological data in semi-arid region (Mirleft, Southern Morocco). The proposed approach provides a comprehensive report on a thin film of calcite mineral ( ) that can be used as a selective shield allowing dew condensation during the night. The increased cooling of the exposed shield (condenser) was exploited using high IR emissivity of the calcite in the atmospheric window (8-13 microns). Indeed, Calcite functions as an excellent passive cooling material due to its strong emission within the atmospheric transparency window (8–13 μ m) and high reflection in the solar spectrum. The dew harvesting happens when the temperature of the shield is below the dew point temperature. The main goal of this paper was to estimate dew harvesting with high yield as a function of condenser temperature and thickness condenser.

Radiative cooling is a passive cooling purpose where a surface naturally cools by radiating the mid-infrared heat radiation to the cold outer space through the atmospheric window . Daytime passive radiative cooling technologies can be simply provided by using a multi-layer design that emits strongly in the transparency atmospheric window, while presents high reflectance in the solar spectrum . In this study, we propose a polydimethylsiloxane foil ) coated aluminum nitride (AIN) deposed onto silver (Ag) coated glass as a radiative cooler for enhancing both daytime and nighttime radiative cooling performances. The spectral selectivity of the proposed device was obtained using matrix method. Numerical results show that our proposed design can reflect more than 96 % in the solar spectrum, while its average emissivity in the atmospheric window can reach more than 90 %.In the absence of wind speed, the proposed device can achieve a net cooling power of under direct sunlight, cooling to a below the ambient air temperature. At nighttime, the proposed device temperature can drop by below the ambient, leading to a net cooling power of . Therefore, the proposed radiative design can fundamentally enable new methods for exploiting solar energy harvesting and energy conservation.