Thin-film solar is a type of photovoltaic panel which uses a thin film of chemicals which can convert sunlight into usable energy. This technology is marketed as an alternative to traditional rigid silicon solar panels. Many people think of silicon panels when they hear “solar panels.” Thin-film solar is markedly different, and the technology is advancing rapidly, as researchers strive to make it as efficient or more efficient than traditional rigid panels.
In thin-film solar, a substrate is covered in materials like copper, iridium, gallium, and selenium to create solar cells. One advantage to this technique, as the name implies, is that the solar cells are more like a thin film than a rigid panel, which means that the technology can be used to turn all sorts of things into solar panels, from windows coated in thin-film solar to strips of metal which can be easily applied to a wide variety of surfaces.
The use of thin-film solar allows for the creation of flexible solar panels, and solar panels which can be easily moved and installed by anyone, rather than requiring the services of an expert. The technology is also much cheaper than that involved in the production of traditional solar panels, as silicon can get quite expensive. Some companies have produced thin-film solar panels with the use of a giant printer, cutting down on costs substantially. Cost-cutting is key for environmentally-friendly technology, as many companies want to make their products accessible to everyone.
Some products made in this way are also more responsive to low light and cloudy conditions than conventional panels. This makes them operable in a wider range of conditions, which can be a distinct advantage in some climates. The ability to respond to low levels of light makes thin-film solar practical in regions where solar power has been largely rejected.
Like all technologies, thin-film solar has a drawback. It is less efficient than silicon panels, meaning that it converts a smaller percentage of the sun's light into usable energy. Early thin solar panels achieved around a 10% efficiency rate, which was not very impressive, although some companies have pushed the number up as high as 20% as of 2009. Constant improvements in the technology will probably increase the efficiency rating even further, making thin-film solar a viable option and a legitimate competitor to silicon solar panels. Companies producing thin-film solar with a high efficiency rating tend to have quite a backlogged order list.