To be able to utilize the sunís radiant energy, some technologies are need. One of them is the solar panel used mainly in generating electricity. This technology is, in fact, the fastest growing among those using
renewable energy sources, according to the Worldwatch Institute report entitled ďRenewables 2005: Global Status Report.Ē
Solar panels gather the sunís energy and help preserve a clean environment. After absorbing the sunís heat, the panels then transform the energy into electricity. A solar panelís surface is made up of solar cells, also called photovoltaic cells.
Solar Panel Types
Solar panels may vary depending on their purposes. Specific panels are used for solar electricity generation and for solar domestic water-heating or home heating and cooling.
Solar thermal panels are mainly used in the homes notably in heating and cooling systems. They are various types such as the flat-plate panels, the evacuated-tube panels and the concentrating type panels.
The most common type is the flat-plate collector. It is made of an insulated metal box and dark-colored absorber plate with a glass or plastic cover. This type of solar panel can collect heat liquid or air at temperatures not exceeding 180 degrees Fahrenheit.
Flat panels are either the liquid or air type. Liquid flat-plate collectors are capable of heating liquid. The air flat panel uses air in providing heat and is less efficient with limited uses.
The evacuated tube collectors consist of rows of glass tubes. Each tube has a glass outer tube and a metal absorber tube with a fin that has a coating. Its name is derived from the fact that air is evacuated from the space between the two glass tubes to form a vacuum that reduces heat loss.
Solar panels function well when positioned in the proper places. They work best is placed on rooftops and on top of buildings or areas which get the most amount of sunlight. To maximize direct sunlight exposure, solar panels found in the northern hemisphere should face south while those in the southern hemisphere should be facing north.
The use of solar panels is growing worldwide especially with the rising cost of generating electricity via the traditional methods. A vital ingredient in making these panels is silicon. However, with the increase in
solar energy usage, silicon is now more costly due to its short supply. Its price in 2004 has gone up by 500 percent to $200 per kilogram today.
Since the middle of the 1990s, the solar industry has improved even going beyond the projected 30 percent yearly growth. This 2008, the increase is pegged at already 50 percent.
Solar panels have their own pros and cons. Primarily, they are eco-friendly because of the absence of emissions and are portable. Solar power, being an
source, will always be in constant supply for even millions of years.
On the contrary, one of the disadvantages of solar powers is their need for more space compared to other types of power plants. Construction of solar systems also entails a lot of cost. They are also less efficient and it is foreseen that the demand for solar panels may exceed the supply. Finally, the solar electric system needs to be well protected from
wind, snow loads, ice and hail.
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