Thin-Film

Thin-film solar panels are made by depositing one or more layers of photovoltaic material onto a substrate such as glass, metal, or flexible plastic. Unlike crystalline silicon panels that use rigid wafers, thin-film technology applies semiconductor material in layers only a few micrometers thick — hundreds of times thinner than silicon wafers.

The main thin-film technologies include cadmium telluride (CdTe), copper indium gallium selenide (CIGS), and amorphous silicon (a-Si). CdTe panels, manufactured primarily by First Solar, are the most commercially successful thin-film type and dominate utility-scale solar farms due to their low production cost per watt.

Thin-film panels offer several unique advantages. They perform well in high temperatures and partial shading, they can be manufactured on flexible substrates for curved or unconventional surfaces, and they have a lower carbon footprint during manufacturing. Some thin-film products are lightweight enough for applications where traditional glass-and-aluminum panels would be too heavy.

The primary drawback is efficiency. Most thin-film panels achieve 10% to 13% module efficiency, significantly below crystalline silicon. This means you need roughly twice the area to generate the same power, making thin-film impractical for space-constrained residential rooftops.

For RV roofs, portable applications, and utility-scale installations where land is cheap and temperature performance matters, thin-film remains a viable choice.