Siamak Azimi-Nam; Foad Farhani
Abstract
Effects of temperature on electrical parameters of polysilicon solar cells, fabricated using the phosphorous spin-on diffusion technique, have been studied. The current density–voltagecharacteristics of polycrystalline silicon solar cells were measured in dark at different temperaturelevels. For ...
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Effects of temperature on electrical parameters of polysilicon solar cells, fabricated using the phosphorous spin-on diffusion technique, have been studied. The current density–voltagecharacteristics of polycrystalline silicon solar cells were measured in dark at different temperaturelevels. For this purpose, a diode equivalent model was used to obtain saturation current densitiesmeasured at the required temperatures. The experimental results showed that the increase intemperature from 27 to 70˚C produced a rapid increase in the saturation current densities from 0.00003to 0.0005A. The changes in the open circuit voltage and the short circuit current density were found tobe linear with the temperature variations: about 3 mV/˚C reduction in the open circuit voltage wasobserved. Measurements of the short circuit current density revealed a very small dependency of thecurrent density on the temperature variations. Accordingly, the short circuit current density increasedfrom 17.8 to 18.4 mA with increase in temperature from 27 to 107˚C. Measurements of the outputpower versus load resistance were obtained at different temperature levels. The results showed that theoutput power dropped by 30% with temperature rise from 27 to 107˚C.
Hossein Ghadamian; Hassan Ali Ozgoli; Mojtaba Baghban Yousefkhani; Foad Farhani
Abstract
Regenerative Fuel Cell (RFC) systems are used for the enhancement of sustainable energy aspect in conventional fuel cells. In this study, a photovoltaic-electrolyzer-fuel cell integrated cycle has been presented. The proposed system has been designed as a novel approach for alleviating the ...
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Regenerative Fuel Cell (RFC) systems are used for the enhancement of sustainable energy aspect in conventional fuel cells. In this study, a photovoltaic-electrolyzer-fuel cell integrated cycle has been presented. The proposed system has been designed as a novel approach for alleviating the restrictions on energy streams in the RFC systems. Modeling of the system has been performed from the mass and energy point of view, based on both theoretical and practical procedures. To generate electricity from hydrogen, a proton exchange membrane fuel cell, integrated with an electrolyzer system which works by solar energy, has been used. Optimized results of required photovoltaic area have shown significantdifferences between theoretical and practical approaches. Moreover, all efficiencies of two scenarios including total efficiency have been indicated and analyzed. The main advantage of this system in comparison with single solar systems, is generation of internal energy of about 2.3 kW for producing 1 kW electricity by the fuel cell.