Why thin film solar instead of conventional pv?

Put briefly, the price of the crystalline silicon wafers that are necessary for conventional solar cells has led the pv industry to look for cheaper materials.

One set of such materials are those that are used with thin film technology. With thin film, the light absorbers need only be 1 micron or so thick, which immediately reduces manufacturing costs.

The three basic materials that have been used for thin film solar applications include amorphous silicon, cadmium telluriden, and copper indium (gallium) diselenide. The important thing about each of these is that they allow for high volume manufacturing, where layers of this material are put on to either coated glass or stainless steel sheets.

Amorphous silicon is still the most well developed of the various thin film technologies. However, their power output is only 15-35% efficient in the direct sun. "Tandem" and triple layer manufacturing has helped, but this adds cost.

Recently, newer technologies have led to steady improvement in solar technology, and production costs are falling. Right now theses new solar cells are powerful enough for lower power and consumer electronics applications, and may be useful building integrated photovoltaic (BIPV) applications.