Nanowire-based solar cells are being developed by a startup in Massachusetts, Bandgap Engineering, in the hopes of lowering costs while increasing power of solar cells twice the current average power generated, from 15 to 38%.
The said project, however, is a long-termed one, but Bandgap Engineering has already started a simpler innovation to solar cells.
Using regular manufacturing tools in solar cells, silicon nanowires could make solar cells absorb more light, boosting power output, the company claims.
Nanomaterials owe their unprecedented properties and efficiency to the increase in surface area or the area of contact. This must also be true to silicon nanowires on solar cells, shown in the SEM micrograph above, more surface area allowing them to absorb more light compared to a conventional flat panel.
In addition, the light absorbed by these nanowires tends to stay longer within them as the refraction of light is such that they will bounce around the numerous minute wires.
These silicon nanowires and the long-term project of developing nanowire solar cells are both based on the minimization of energy loss through unabsorbed, wasted light transformed into heat or just bounced off the cell.
Bandgap Engineering’s ultimate goal, however, is to change the process of converting light to electricity in such way that low-energy light, which is usually wasted as heat, can also be converted to useful electrical energy. They deem this to be possible if they can make the nanowires uniformly such that their atoms are aligned at certain angles, allowing changes in the electrical properties of silicon.
[via technologyreview]
