Our sun offers a potentially huge reserve of clean, free, endless energy. All that is needed to convert solar energy into usable electricity is a photovoltaic (PV) system. Most people are familiar with photovoltaic cells or have seen them work before, such as on solar powered calculators, emergency road signs and call boxes, and other places. As PV technology has advanced, a new type of PV material has begun to be used, namely photovoltaic film. This film has the same function as the traditional PV cell, but with a construction that makes it flexible and much more versatile.
One of the biggest advantages to photovoltaic film is that it can harvest as much energy from the sun as traditional solar cells, but it takes about 100 times less semiconductor material to make photovoltaic film. This means that the manufacturing costs goes down substantially in comparison. This is especially intriguing to those who see PV systems as an alternative source of energy.
In the past, it has been precisely the cost of the needed materials that made PV cells so expensive, and therefore impractical as a means of generating electricity on a large scale. The development of photovoltaic film represents a very important advance towards the viability of large-scale energy production by PV systems.
Another noteworthy point is that photovoltaic film can actually generate more electricity under some conditions than traditional PV cells. They can also perform better under high-temperature conditions, are lightweight, and are not nearly as fragile, since no glass is used in their construction.
Traditional PV cells are made using two layers of different types of silicon crystals that have different electrical characteristics. These silicon layers allow electrons to flow through them when they come in contact with photons, the subatomic wave-like particle that is visible to us as light. A backing and a contact grid are then placed on either side of the two-layer silicon construction. Since silicon is a highly reflective material, an anti-reflective coating is then added. The whole structure is then put into a sturdy frame with a glass cover, and positive and negative electrical terminals are placed on the back.
Photovoltaic film is constructed using the same basic technique, although alternative materials allow for these systems to be much thinner and have no need for a glass cover. Many scientists and other people familiar with PV systems anticipate that photovoltaic film will supplement and be complementary to traditional silicon PV systems, without replacing the older systems altogether or making them obsolete.