Question

How do you classify solar energy devices? Explain.

Answer 1

1. Devices that are used to harness solar energy for practical purposes are called solar energy devices.
2. These are classified into two categories based on their principle of working.

a) Solar cooker and heaters

b) Solar cells

Solar cooker and heaters:

1. Solar cookers concentrate sunlight onto a receiver such as a cooking pan.
2. The interaction between the light energy and the receiver material converts light to heat and this is called conduction.
3. This conversion is maximized by using materials that conduct and retain heat.
4. Pots and pans used on solar cookers should be matte black in color to maximize absorption.
5. 

Solar Cells

1. A solar cell, or photovoltaic cell, is an electrical device that converts the energy of light directly into electricity by the photovoltaic effect, which is a physical and chemical phenomenon.
2. It is a form of photoelectric cell, defined as a device whose electrical characteristics, such as current, voltage, or resistance, vary when exposed to light.
3. Individual solar cell devices are often the electrical building blocks of photovoltaic modules, known colloquially as solar panels.
4. The common single-junction silicon solar cell can produce a maximum open-circuit voltage of approximately 0.5 volts to 0.6 volts.
5. In addition to producing energy, they can be used as a photodetector (for example infrared detectors), detecting light or other electromagnetic radiation near the visible range, or measuring light intensity.
6.