What is Photovoltaic & How Solar Works

how_solar_worksHow Small Solar Electric Systems Work

If you are thinking about installing solar in your home, you may have a few questions.  “What is solar? How does it work?”  Simply put, solar electric systems, also known as photovoltaic (PV) systems, convert sunlight into electricity.  Photovoltaic is defined as: a field of semiconductor technology.  It involves the direct conversion of electromagnetic radiation as sunlight, into electricity. A pholovoltaic system is the device designed to perform such a converson

Solar cells

Solar cells are the basic building blocks of a PV system.  They consist of semiconductor materials. When sunlight is absorbed by these materials, the solar energy knocks electrons loose from their atoms. This phenomenon is called the “photoelectric effect.” These free electrons then travel into a circuit built into the solar cell to form electrical current.  Only sunlight of certain wavelengths will work efficiently to create electricity. PV systems can still produce electricity on cloudy days, but not as much as on a sunny day.

 

How much power does a panel produce

The basic PV or solar cell typically produces only a small amount of power. Most likely you have solar lights around your home.  They have a small panel on top,  and a battery to store the power, which is then used to light the bulb- right?  Think bigger.  Much bigger.

To produce more power, solar cells (about 40) can be interconnected to form panels or modules. The average solar panel output ranges from about 175 W to about 235 W.  An exceptionally powerful solar panel will measure upwards of 315 W. Among the top ten manufacturers, the average wattage of a panel is about 200 W. If more power is needed, several modules can be installed on a building. They may also be installed at ground-level in a rack to form a PV array.

PV arrays can be mounted at a fixed angle facing south, or they can be mounted on a tracking device that follows the sun.  That will allow them to capture the most sunlight over the course of a day.  Panels have been designed that can be placed in an area that has some shade which is helpful to those who do not wish to cut down all their trees.

Because of their modularity, PV systems can be designed to meet any electrical requirement, no matter how large or how small. You also can connect them to an electric distribution system (grid-connected). They can also stand alone (off-grid).