Photovoltaic Advancements – Solar Cells May Really Become Common One Day
If you’ve been wondering where our solar cells are and why they’re not just everywhere yet as the green revolution churns onward, there’s a reason for that. So far their construction still requires all manner of expensive rare materials such as silicon and cadmium. And because of the way that they’re manufactured, silicon panels grown in vacuum, they’re just plain expensive to produce. So as much as we’d like to see a solar renaissance, where we finally go from wow to now, it’s just not happening.
But all that may change.
Researchers at IBM think that they’ve hit the next best thing since sliced silicon: “High-Efficiency Solar Cell with Earth-Abundant Liquid-Processed Absorber” It’s a completely new take on producing solar cells, based primarily on more “earth-abundant” materials such as copper, zinc, tin, selenium, and sulfur in a chalcogenide compound. In fact, unlike silicon-based photovoltaics which have to be grown in a vacuum, these materials can just be sprayed on. They’re applied in a slurry state, so spraying, dunking, printing, spin-coating, or what have you can be done to apply them to the solar cells. So not only are the materials more friendly and available, but they’re applied in a process that is much cheaper and easier to manufacture. And because they’re basically painted on, they can be applied to all sorts of shapes that would cause traditional solar panels to shatter if attempted. The next paint job on your car or house might be “High-Efficiency Solar Cell with Earth-Abundant Liquid-Processed Absorber”.
The only downside is that so far the efficiency rate is only around 9.6 percent. That’s a bit shy of today’s silicon-based photovoltaic efficiency between 10 and 15 percent. Though researchers do like to point out that the technology is still in an early phase and efficiency may improve as the process is refined. And still, for the price and theoretical availability, what one lacks in efficiency one can easily make up for in volume.
But Big Blue isn’t the only horse in this race. Researchers from the California Institute of Technology in Pasadena have made their own headway in a new photovoltaic direction: silicon wires.
In a new paper published in Nature Materials entitled “Enhanced absorption and carrier collection in Si wire arrays for photovoltaic applications” is described an entirely new process of solar absorption using arrays of 1mm thick silicon wires to create a flexible polymer. This is a markedly different direction from the normal use of silicon in solar panels. It uses far less material, a mere 1 percent of the silicon needed for traditional solar panels. And yet in spite of the incredible reduction in the amount of silicon used (or perhaps because of it) panels made from these silicon wires have been measured at 17 percent efficiency, blowing away the competition.
What’s more, the bundles of silicon wires absorb solar energy “over a broad range of incidence angles“, meaning that they don’t need to be adjusted for optimum absorption nearly as often as traditional solar panels.
And just as amazing, because these panels are made from bundles of silicon wires, they’re flexible. So not only are they much less likely to be damaged from things that would normally ruin the traditional brittle silicon panels, it’s a technology that would be easy to adapt to locales that aren’t traditionally flat, such as car roofs, or even the curtains in your window!
With the incredible savings and improvements in manufacturing that each of these new solar technologies offer, we just one day may find photovoltaic solar panels common building materials available to every home. And with the flexibility that they offer, solar energy just may make the jump from small electronics and home panels to … everything and anything. What a wonderful world it would be.

