Demos: 3D-05 Alternative Energy Sources
The Solar Cell demonstrates the conversion of light (solar) energy to electrical energy. A Solar Cell is layered and functions by creating an electric field. The top layer of the cell is slightly negative. The lower layer is slightly positive. When light shines on the cell, photons are absorbed and electrons are released. These electrons are attracted to the lower positive cell and establish an electric field. This panel consists of two small modules that can be connected in series or parallel allowing you to double the current or the voltage. An incandescent lamp is necessary to provide enough light energy to power the fan. In direct sunlight the cell will generate 14 volts. You can demonstrate the conversion of energy by powering the fan or attaching the panel to a voltmeter.
The fan demonstrates the conversion of mechanical (wind) energy to electrical energy. The source for the wind is a hair drier. With the hair drier switched on high, the fan will generate about 4 volts. You can demonstrate this conversion by plugging a light source into the fan or a voltmeter.