Journal of Selected Topics in Energy

The limited available energy resources and it basic role in industrial development, employing the renewable sources of energy including wind, sun, water and etcetera as appropriate choice described. Renewable energies are not only economically advisable, but even can contribute to provide a cleaner approach of energy production and healthier environment. Hence, assessment of some old structures such as Middle East wind catcher that are established on the ground of clean energies and adapting them to the modern age demands with optimizing models is noteworthy. This work, by keeping focus on calculus of variation and analysis of the wind load on the wind catcher structures and present an optimal more resistant model. Optimization of the design parameters of wind catcher structures led to a hyperbolic model with least wind catcher surface and a higher stability and strength compared with the older structures of this category.

Solar energy is the most important type of modern and renewable energies. If it displace fossil fuels, can bring an end to concerns about finiteness of fuels, environmental pollution caused by the fossil fuels, price fluctuations and energy crisis. Among the energy sources, due to the high potential of solar energies in wide areas of the Iran, it has a great importance to researchers. The base of Photovoltaic technology is to converting sunlight into electricity and nowadays, most of the countries utilize it in the forms of grid-connected and off-grid. In recent years, few technologies are used for manufacturing of solar cells. The results  of investigating show that the efficiency of the first generation in comparison to the other technologies are high due to the high quality raw materials which are used in the fabrication. It is expected that the differences between the efficiency of these for technologies will be decreased by the time and other technologies will be replaced by the first generation. In this paper, the structure of different technologies has been studied and the possible methods for improvement of the solar cells efficiency have been introduced.