Monday, February 23, 2009

Energy Payback Time for Photovoltaic Technologies

The length of deployment that is required for a photovoltaic system is measured by the length of energy payback time. This means that a photovoltaic system must generate a total amount of energy that is equal to the amount of energy that is used to produce the electricity. According to engineer studies a low energy payback time is found with a roof mounted photovoltaic system.

Energy payback time is valued according to three different factors. The first factor is the amount of illumination or sunlight the system receives. The second factor is the way in which the photovoltaic system converts efficiency. The third factor deals with the type of manufacturing technology that is utilized to make solar or photovoltaic cells.

There are three approaches to the manufacturing of solar cells, commercially, according to developments in manufacturing technology. The most popular approach to processing discrete cells is by using silicon ingots in the form of wafers. The conductors or ingots is what develops the highly intensive energy process. The conductors are usually either multi or single crystalline.

A recent development in the approach of saving energy is the processing of discrete cells that originate from the multicrystalline ribbons. Another approach that has been developed is to deposit layers of silicon materials that are non-crystalline on a substrate that is inexpensive. The last mentioned approach is considered to be the least energy intensive of all of the manufacturing approaches for photovoltaic devices used for commercial purposes.

Another form of technology that is used in solar or photovoltaic energy uses amorphous silicon cells. The silicon cells are then deposited on ribbon made from stainless steel. Cells consisting of cadmium telluride is deposited onto glass. Then alloy cells made from copper indium gallium are deposited on stainless steel substrates or glass. These are some of the latest ways in which photovoltaic devices generate electricity. There have been recent studies that have established grid-tied EPBT systems, battery-free that are used when creating new and improved photovoltaic module technologies.

No comments: