Solar Panels – An introduction
Solar Panels (also known as PV Cells) are the major source of electricity generation applications in commercial and residential deployments around the world. These small sized PV (Photovolatic) Cells are deployed in a collection or an array format to generate large amount of electricity.
Here we look at what they are made of and how they function.
The basic principle of Solar panels is to use the sunlight to generate electricity using the photovoltaic effect. It generates electricity when light (photons) hit the silicon wafers. These photons contain different amounts of energy and when they hit the PV cells, they are either reflected or absorbed. The photons that get absorbed will transfer its energy to electrons thus generating electricity.
Types of Solar Panels:
Monocrystalline panels are the considered most efficient ones. That’s why they are most commonly deployed too. You need only few of them to generate high electricity rates which is ideal for short space deployments such as roofs. However, they are also very expensive.
Polycrystalline panels, also known as multicrystalline panels, are less efficient, but less expensive to produce. They take up less amount of silicon and look a little different than Monocrystalline panels.
Thin Film Panels, also known as Amorphous Panels, are very thin and extremely inefficient in generating electricity. They are very cheap to make and usually are deployed in large fields rather than roofs where space is an issue.
Solar Panel Mounting:
There are three major ways a panel can be mounted – Fixed, Adjustable or Tracking. Fixed panels are the least costly and are most commonly found on roofs. Once you install them on your roof, you forget about making any changes to its angle etc. The Adjustable ones are most commonly found in fields where you adjust for Sun’s angle in winter and summer. The Tracking panels will follow the path of Sun as the day progresses and are the most expensive ones. Overall the Tracking panels will generate 20% to 40% more output than the fixed panels.
Due to very low voltage of individual cell, they are deployed either in serial format to generate high voltage output or in wired in parallel to generate high currents. Panels are manufactured in a weather proof casing making them solid and ready for use in rigid environments. A PV array is a collection of Solar Panels typically deployed in residential and commercial applications. These arrays generate direct current (DC) which is then transferred into AC power using inverters. These panels have no moving parts and are very earth friendly with very minimum waste.