Researchers at Sandia National Laboratories have come up with a new photovoltaic cell no bigger than a flake of glitter, but it packs a big punch. The new cell uses 100 times less silicon to generate the same amount of electricity as conventional solar cells. While still in the development stage, the new solar particles could lend themselves relatively easily to commercialization because they are made of crystalline silicon and use the same micro-manufacturing processes typical of modern electronics.
The new cells can be made from available silicon wafers of any size, without some of the quality control problems involved in conventional solar cell manufacturing. The Sandia researchers also expect them to be less expensive, more durable and more efficient that conventional solar collectors, and they could open up an exciting new range of applications.
The Sandia researchers foresee the potential for solar particles to be applied irregular surfaces including fabrics, which would make every tent, tarp or article of clothing into a potential battery-charger. That has significant implications for the U.S. military, which is eagerly seeking harvestable solar energy and other forms of scavenged energy to power its electronics-laden field personnel with less of a logistics burden, and to help reduce its reliance on vulnerable fuel convoys to deliver energy to remote outposts.
The Sandia team also cites the potential for applying the tiny photovoltaic cells directly to roofing materials, which would practically eliminate the often cumbersome permitting process that is currently needed to install a conventional rooftop solar array (Dow has taken a similar approach with its new solar shingles). Compared to six-by-six inch conventional solar cells, the new solar particles are only up to 20 micrometers thick, less than one third the thickness of a human hair, and they could be imprinted with circuits that would control the collection and disbursement of solar energy within the building and to a grid connection, without the need for expensive and time-consuming electrical design work. Roof maintenance, repair, and shading issues may also be mitigated due to the small size of the micro-cells.
Solar cells are getting smaller, and surgical implants are among the intriguing possibilities for the future use of microphotovoltaics. Just this month, researchers at Stanford University announced that they have developed a retinal implant with solar cells. The project pulled together ophthalmologists, electrical engineers, neurobiologists, and biophysicists. It resulted in a built in “high-def TV” that could enable some blind persons to see shapes and meaningful images, using tiny photovoltaic cells to convert light into electrical impulses. The project was developed with a silicon implant that used tiny “bridges” to follow the shape of the eye, and the use of micro-cells might enable an even more flexible design approach.