Thin Film vs. Convention Solar Panels

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

One set of such materials are those that are used with thin film solar technology. With thin film solar tiles, 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 roofing 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 of solar roofing tiles and panels, 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 solar technologies. However, their power output is only 15-35% efficient in the direct sun. "Tandem" and triple layer thin film solar manufacturing has helped, but this adds cost.

Recently, newer technologies have led to steady improvement in thin film solar technology, and production costs are falling for solar roofing tiles and panels made this way. 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.