A solar cell is the basic unit that is able to convert solar power into electricity. However, in a solar panel you get four of these. A single solar panel is able to produce a voltage of 0.45 volts. When you connect a series of solar panels you will be able to provide significant voltage which could provide sufficient power to perform mechanical tasks. The most common applications of solar energy are found in wrist watches and calculators. They are being developed to run cars and certain electrical equipment also. There is a lot of enthusiasm in the use of solar energy as it is one of the most important sources of renewable energy.
The basis of production of electricity by a solar cell is simple. It is normally made up of silicon. This metal has a property of releasing electrons when sunlight falls on it. Whenever there is a movement of electrons there is generation of electricity. These electrons are able to move freely due to the presence of impurities in silicon. In a solar panel you get the silicon surrounded by a protective material and the two are framed in a metal frame. The transparent protective material embeds the solar cells. There is a glass cover to protect the panel.
In order to measure the efficiency of a solar cell there are two parameters. One measures how much of the solar energy that falls on the cell could be converted into electrical energy that could be used for some purpose. This is called the energy conversion efficiency. A solar cell is able to absorb only 25% of the energy in the sunlight that falls on it. This is an inherent property of silicon. One of the reasons for this weakness is that silicon offers a resistance to photons of the sunlight.
The other measure of thermodynamic efficiency measures the ability of a solar cell to convert the absorbed energy into electrical power. The maximum attained so far is 86%. In case you want to determine the efficiency of a solar panel you need to consider both these parameters. Since the efficiency of solar panels is limited, there is a lot of room for improvement. However, solar panel has come a long way at the moment as it is being used in many areas. There is all possibility for it to improve up to the level of providing total power requirements of individual homes.