Mini photovoltaic cells developed at Sandia Labs promise an unprecedented energy punch in a small package
Imagine cellphones that never need charging, camping tents with electrical outlets, battery-free automobiles and clothing that collects solar power as you walk down the street. Imagine solar being the most cost-effective and efficient energy source available.
Go ahead and dream, because a team of some 30-plus scientists and researchers at Sandia National Laboratories are closer to this new reality than many people realize. Called the “Microsystems-Enabled Photovoltaic Project,” the team headed by Principal Investigator Gregory Nielson has developed solar cells smaller than a pinhead.
The solar particles — or “solar glitter” as they are called because of their minute, sparkly appearance — hold the potential to revolutionize the way solar energy is collected and used, opening the door to a variety of new efficiencies and applications, said Jose Luis Cruz-Campa, a senior member of the Sandia technical staff developing solar glitter.
Jose Luis Cruz-Campos
We believe it can be a game-changing technology,” Cruz-Campa told Local iQ
in a recent interview on the Sandia campus.
It’s an idea Nielson started to explore in 2008. His concept was to use techniques and tools common in modern computer chip factories to create teensy solar cells that could generate more power in less space, from fewer materials than conventional solar cells. But could it even be done?
“In the electronics industry, every year there’s something better, faster and cheaper,” Cruz-Campa said. “We wanted to know, can we make solar like that?”
Cruz-Campa was a PhD student at the University of Texas El Paso when he heard of the solar glitter concept at Sandia. He pursued an internship there so he could dig into it deeper, wrote his dissertation about it, did his post doctoral studies on it, helped get more funding for it and eventually snagged a job as a team leader devoted to full-time solar glitter research.
Typical silicon solar wafers are 6 inches square, and the technology has changed very little in the last 40 or so years. If one cell goes out or is shaded in a conventional solar panel, the entire panel shuts down — “Like Christmas lights,” Cruz-Campos said. Efficiencies are good but not great, the cost of production can be high and installation is not cheap.
Magnified image of individual photovoltaic cells
Enter solar glitter. By using microfabrication techniques borrowed from the electronics industry, Sandia researchers found they could make solar cells that use 100 times less silicon to produce the same amount of electricity. The cells themselves are far thinner than human hair, and a sheet of these cells can produce twice as much power for less than half the cost of traditional solar panels — and crank out more voltage in a much smaller space.
So the back of a cellphone could be home for hundreds of tiny solar cells, keeping the phone charged as it sits on a table and collects light. Or the fabric of a camping tent could be peppered with these solar cells, providing power for everything from a coffee grinder to a reading lamp. The more intensive and efficient power potential of solar glitter opens exciting possibilities.
Sandia has patented the solar glitter technology, and the lab’s research team for the project — headed by Nielson, Cruz-Campa, Munat Okandan, Vipin Gupta and Jeff Nelson — is now focused on getting to a “technology readiness level,” at which point solar glitter can be adopted by industry and the possible applications for it can be explored even further. That will be at least two more years, “in an ideal world,” Cruz-Campa said.