Solar cells get efficient as time goes, but there are methods to improve the performance of current ones, made with older technologies. Wake Forest Center for Nanotechnology has just received a patent for a new solar cell technology that can double the energy production of current silicon flat cells at highly reduced costs.
The new solar cells the scientists developed are made of millions of minuscule plastic fibers collecting the light at different angles, and being able to cover sunsets and sunrises. The new fiber-based solar cells will be able to produce about twice as much energy daily as standard solar cells.
David Carroll, the director of the center, says: “We’ve been able to show that with a standard absorber we can collect more of the photons than anyone else can. Because of the way the device works, I get more power.”
To make the cells, the plastic fibers are assembled onto plastic sheets, with a technology similar to that used to create the tops of soft-drink cups. The absorber – either a polymer or a dye – is sprayed on. The plastic makes the cells lightweight and flexible – a manufacturer could roll them up and ship them anywhere cheaply.
Where flat cells lose energy when they reflect the incident light, the fiber-based solar cells have more suface area, trapping the light in the tiny fiber “cans” where it bounces around until it’s absorbed almost completely.
The new fiber solar cells could have application in green buildings, being able to be integrated almost anywhere in the building’s design, not only on the roof.
Fiber solar cells are not a new approach in the area: a few months ago I wrote about an independent experimenter who devised a similar fiber-based system with the same applications. Besides him, there is a team from Georgia Tech who tinkered with the design.
Concentrating cells allow an increased flux of photons to the smaller receiver absorber using a larger aperture to collect the solar light.