Photovoltaic (PV) Panels

Photovoltaic (or solar) panels start the process.  They convert sunlight into direct current (DC) electricity.  A panel is composed of modules, which are in turn made up of individual solar cells.  Each cell in a panel contains semiconductor material that uses light (or photons) to generate electricity.  This is known as the Photovoltaic Effect, discovered by Edmond Becquerel in 1839.  Basically, photons strike the panel displacing electrons in the semiconductors, causing voltage to be created and a current to flow, if a circuit is connected to the panel.  The first positive/negative (p/n) junction solar cell was not created until 1954 at Bell Labs.

PV panels are rated according to the maximum number of watts they can produce under ideal conditions of sunlight and temperature.  When multiple panels are connected together they are called an array.  An array is connected together to produce a single electrical output.  The bigger the array (i.e., the more panels), the more wattage produced.

The performance of a solar cell is measured in by its efficiency at turning sunlight into electricity. Only sunlight of significant strength will work efficiently to create electricity, and much of it is reflected or absorbed by the material that make up the cell. Because of this, a typical commercial solar cell has an efficiency of 13% to 15%—about one-sixth of the sunlight striking the cell generates electricity.  Higher end cells have efficiencies of over 16%, but to get this extra efficiency, they are significantly more expensive.

These panels are very durable and rugged, and will last many years.  Most PV panels, like the ones used by North Star Energy Services, are warrantied for up to 25 years.