Abstract:

Solar photovoltaic (PV) energy systems is one of clean energy technologies actively being used. It is also finding its wide usage in countries with abundance of sunlight. One of such places is Republic of Botswana where PV systems used in different applications such as street lighting, borehole water pumping, telecommunications repeater stations, household lighting. The usage prompted further research on improvement of power output and overall efficiency of the system. Dealing with power output means studying further PV module which is an important part of solar photovoltaic energy system. Important role played by solar photovoltaic module is to convert solar power into electrical power. To study the PV module output, a PV cell electrical characteristics can be studied because it will resemble the characteristic behavior of the module considering that the PV panel is an assembly of cells of photovoltaic material that are connected together mechanically and at the same time making a complete electrical circuit. The characteristics of interest are the outputs of voltage and power at its maximum value. The electrical characteristics of the module are affected by a different factors such as ambient temperature, amount of solar radiation, humidity, and wind velocity. To study the PV module electrical characteristics being yearly voltage output profile and profile of the maximum power, this paper presents Simulink-model to analyse a model of single diode used to represent a PV cell used in simulations. The results show generally constant value of voltage output obtained all year round whereas the profile of maximum power follows the solar insolation profile

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