Photovoltaic Cells
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Photovoltaics deals with the conversion of light into electricity using materials which exhibit some form of photovoltaic effect or properties. These materials tend to be semiconductors in nature, and range from crystalline and amorphous silicon, to copper indium gallium sulfide selenides [21]. These elements tend to absorb sunlight and release energy which can be converted into electricity. This is known as the photovoltaic effect which was first observed by Alexandre- Edmond in 1839.
The sun releases photons to the earth every hour. These photons collide with the semiconductor in the photovoltaic panels/cells at the speed of light thereby exiting electrons into a higher state of energy, allowing them to act as charge carriers for electric current. The panels consist of cells which create electric filed, and the photons then create electric current in the panel which can be used to power an equipment or recharge a battery [13]. The amount of electricity created depends on the number of cells available to produce electric current. In order to produce enough electricity, photovoltaic cells have to be connected in an array to form panels or modules. The most common array type design is the flat-plate photovoltaic modules.
The angle of installation ranges from 11.6 degrees in the summer when sunlight is optimal to just above the optimal angle at 49.8 degree in the winter where there is less sunlight. These angles are specific to areas between 30-35 degrees north of the equator which includes Texas [20]. These arrays are significant to how effective the photovoltaic cells would be. They also tend to be light weight and not that expensive due to its ease of installation and immobility.
Several technological advances have made photovoltaic cell more efficient and increased its reliability. Due to the increased demand for renewable energy sources, the manufacture of photovoltaic cells and arrays has been on the rise in recent years.
The sun releases photons to the earth every hour. These photons collide with the semiconductor in the photovoltaic panels/cells at the speed of light thereby exiting electrons into a higher state of energy, allowing them to act as charge carriers for electric current. The panels consist of cells which create electric filed, and the photons then create electric current in the panel which can be used to power an equipment or recharge a battery [13]. The amount of electricity created depends on the number of cells available to produce electric current. In order to produce enough electricity, photovoltaic cells have to be connected in an array to form panels or modules. The most common array type design is the flat-plate photovoltaic modules.
The angle of installation ranges from 11.6 degrees in the summer when sunlight is optimal to just above the optimal angle at 49.8 degree in the winter where there is less sunlight. These angles are specific to areas between 30-35 degrees north of the equator which includes Texas [20]. These arrays are significant to how effective the photovoltaic cells would be. They also tend to be light weight and not that expensive due to its ease of installation and immobility.
Several technological advances have made photovoltaic cell more efficient and increased its reliability. Due to the increased demand for renewable energy sources, the manufacture of photovoltaic cells and arrays has been on the rise in recent years.
Solar Thermal Technology
Solar thermal technology uses the Sun's energy to generate thermal energy, which can then be used to heat flids. Solar thermal energy can be used in many ways, including:
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Passive Solar Heating
A passive solar home is designed to let in as much sunlight as possible. It is a big solar collector. Sunlight passes through the windows and heats the walls and floor inside the house. The light can get in, but the thermal energy is trapped inside. A passive solar home does not depend on mechanical equipment to move heat throughout the house [6].
Passive homes can get 30 to 80 percent of the heat they need from the sun. They store their heat energy by using thick walls and building materials that retain heat well like masonry, concrete, stone, and even water. |