Since the early days when it was only used in niche applications, solar power has matured greatly, gaining efficiency and durability along the way. Through research and development to building and testing a range of new ideas and theories, engineers, scientists and manufacturers continue to push the boundaries on how much sunlight solar cells can convert into usable energy.

One of the recent innovations now being used in commercially available solar modules is black silicon.

What are black silicon solar cells?

Making silicon “black” refers to the process of etching tiny nanostructures on the surface of a silicon solar cell. This process may involve plasma immersion, the use of additives, laser texturization or metal-assisted wet etching. These nanostructures increase the surface area of the cell, and increase the amount of sunlight that is captured rather than reflected back from the cell.

Initially, this technology was viewed as a way to reduce the cost of diamond-wire sawn multi-Si wafers. However, black silicon technologies also increase the efficiency of solar cells. Turning solar cells “black” like this increases the amount of sunlight absorbed into the cell, reduces the amount of light reflected off the modules, essentially making them less shiny. In addition, the nanostructure of the black silicon structure allows the cell to absorb more light at wider angles, as opposed to regular crystalline silicon that absorbs indirect photons less efficiently than direct sunlight. Furthermore, black silicon is better at absorbing shorter wavelengths of light, which traditional technologies often struggle with. With the ability to capture more sunlight, these solar cells are able to achieve higher efficiency levels as they convert more light as the Sun moves across the sky.

Trina Solar has always taken a leading role in the research and development of groundbreaking solar technology, and achieved a new efficiency record for black silicon solar cells of 23.5% on a large-area, mono-crystalline, square silicon wafer, 156 millimeters across, in April 2016.

Click here to learn more about Trina Solar's solar modules that use black silicon.