using photovoltaic systems is gradually expanded by increasing energy demand. abundance and availability of this energy, has turned to one of the most important sources of renewable energy. unfortunately, photovoltaic systems have two big problems: first, those have very low energy conversion efficiency (in act between 12 and 42 percent under certain circumstances). second, the power produced b...

in this article using comparative multi-purpose algorithm of pso, optimum capacity of new resources and their spinning storage is defined. spinning reserve requirements and optimized to maximize profit per unit is determined according to uncertainty. in fact by increasing the level of cost reservation, power supply increases but penalty of blackout decreases. in this paper in has been tried to ...

colloidal quantum dots offer broad tuning of semiconductor band structure via the quantum size effect. in this paper, we present a detailed investigation on the influence of the thickness of colloidal lead sulfide (pbs) nanocrystals (active layer) to the photovoltaic performance of colloidal quantum dot solar cells. the pbs nanocrystals (qds) were synthesized in a non-coordinating solvent, 1-oc...

Using Photovoltaic systems is gradually expanded by increasing energy demand. Abundance and availability of this energy, has turned to one of the most important sources of renewable energy. Unfortunately, photovoltaic systems have two big problems: first, those have very low energy conversion efficiency (in act between 12 and 42 percent under certain circumstances). Second, the power produced b...

the increase of cell temperature with increased irradiance is probably the mostsignificant disadvantage of using photovoltaic modules equipped with booster reflectors. the aimof this study is to investigate the possibility of improving the performance of a photovoltaic waterpumping system by using a booster reflector and to keep the temperature of pv panels at a lowlevel by cooling pv panels wi...

The low conversion efficiency of solar cells produces large amounts of thermal energy to the cells, and with an increase in the temperature of solar cells, their electrical efficiency decreases. Therefore, a hybrid photovoltaic thermal system improves the overall efficiency of the system by adding thermal equipment to the solar cell and removing excessive heat from these cells. In this paper, w...

Photovoltaic cells, as the primary part of a solar photovoltaic system, are a nonlinear DC power supply related to multiple parameters. The demand of increasing the generating efficiency of photovoltaic cells requires having a good understanding of their electrical characteristics. In this study, the mathematical and physical model of the photovoltaic cells was built by the means of Matlab and ...

the main problemswith the use of fossil fuels is the restrictions on their access and the detrimental consequences of their use which causes a threat to human health and quality of life. consequently, the use of other energy sources has become necessary. renewable energy as a permanent and clean energy source is an answer to this problem. one such energy source includes photovoltaic solar energ...

it is expected that residential units may replace   traditional heat and power production systems with cogeneration ones. among the different cogeneration systems, fuel cell based systems are a suitable choice due to their high efficiency, high power density, low emission and low noise. in this paper, a cogeneration system based on solid oxide fuel cells is examined. the system, including the f...

We investigate the one-parameter Calabi-Yau models and identify families of D5-branes which are associated to lines embedded in these manifolds. The moduli spaces are given by sets of Riemann curves, which form a web whose intersection points are described by permutation branes. We arrive at a geometric interpretation for bulk-boundary correlators as holomorphic differentials on the moduli spac...