An amorphous solar cell (also often referred to as a thin-film cell) is a variation of silicon solar cells in which the silicon used does not possess a regular crystal structure. In short, it describes an extremely thin layer of disordered silicon that is vapor-deposited onto a substrate material such as glass, plastic, or metal to convert light into electricity.
In a nutshell: While classic, crystalline solar modules consist of thick, rigid silicon wafers, amorphous solar cells are as thin and flexible as a coating. They are known in small format from calculators or in large format as flexible solar films for uneven surfaces.
How do amorphous solar cells work?
The basic function is based, as with all solar cells, on the photovoltaic effect. However, because amorphous silicon (a-Si) absorbs light much more strongly than crystalline silicon, an extremely thin layer of less than one micrometer (one thousandth of a millimeter) is sufficient to capture sunlight.
During manufacturing, the silicon is applied directly to the desired substrate material in a gaseous state. Because this eliminates the need to grow complex and expensive crystal lattices, the production of these cells is significantly more material-saving and cost-effective compared to monocrystalline modules.
Advantages and features at a glance
Although amorphous solar cells have a lower efficiency than crystalline modules, they offer unbeatable advantages in certain fields of application:
- Excellent low-light performance: Amorphous modules operate comparatively efficiently even in diffuse light, fog, heavy cloud cover, or during morning and evening hours.
- High flexibility and low weight: The thin-film process allows the manufacturing of flexible modules that adapt perfectly to curved roofs, motorhomes, boats, or even backpacks.
- Low temperature sensitivity: While conventional solar modules experience a significant drop in performance on hot summer days, the yield of amorphous cells remains stable even at high temperatures.
What should you consider during application?
Due to their lower efficiency (usually between 6% and 10%), amorphous solar cells require significantly more surface area to generate the same amount of electricity as a monocrystalline module. Therefore, they are usually the second choice for classic residential roofs with limited space. Instead, they unfold their full potential on lightweight roofs that cannot support heavy loads, in mobile solar solutions, or on surfaces that are frequently affected by partial shading or diffuse light.