Understanding Photovoltaic Cells
Photovoltaic cells, also referred to as solar cells, have a basic process that takes sunlight and convert it into electricity. Discovered in 1954, scientists found that silicon could be used to make an electric charge, if it was exposed to direct sunlight. Technology advanced, and with it solar cells were soon powering satellites, and even our most basic commodity; a watch or calculator. In today’s high tech world people now use these cells to power their homes, businesses, and utilities companies are now taking PV technology even further, by using this technology for power stations.
First generation solar panels that are used in businesses and homes, will normally use modules that hold as many as 40 cells. In order to provide electrical needs for an average home, one would need to use 10 – 20 panels, that are fixed at an angle; usually south. Some will use a mount design, that allows for a tracking device, that then moves with the sun, allowing for optimum sunlight to hit the panels. When you combine panels together you’ll hear them referred to as a solar array. Large solar arrays are most often used to power electric utility companies, or large industrial complexes. When interconnected, these solar arrays enable large PV systems to power thousands of homes and buildings combined.
As stated earlier, these cells are made from silicon, often found in sand, and are considered to be one of the most efficient types of solar panels. Cells that are second generation are comprised of amorphous silicon and nonsilicon materials. These cells are thin film cells, use semiconductor materials, and their thickness is measured in micrometers. Their flexibility and thinness gives them the appearance of house tiles or shingles, thereby making them a perfect choice for roofs, tiles, glazing on skylights and building facades.
Third generation cells are made from a variety of materials. Inks used in printing press technology, conductive plastics, and solar dyes are the main ones currently being produced. As technology continues to advance in this field, we’re seeing solar cells using lenses made of plastic or mirrors, as a way to concentrate and enhance rays from the sun, into smaller than ever and more efficient PV materials. Although more expensive to purchase, less panels need to be used, thus making them a cost effective option for industrial uses, and for whole utility company usage. Concentrating collectors that use lenses have the drawback, that they are only suitable for some areas where there is a higher concentration of sun yearlong.
As we head into the future, it’s expected that solar technology will accelerate at an amazing pace, due to solar technology advancing and becoming smaller every year. Currently many homes are using this technology, as are businesses, but as solar become smaller and more affordable, prices will continue to drop, thus enabling the average homeowner to afford this new technology and go off-grid or sell power back to the grid.
The National Center for Photovoltaic offers information on all the latest research in solar cell PV technology, and currently supports the DOE SunShot Initiative, that plans to have large scale solar systems, that are cost effective by 2020. Everblue Courses are designed to teach about home energy efficiency and create knowledgeable technicians for the coming expansion of sustainable energy.