Increasing the amount of energy hitting a solar cell that can be converted into usable electricity to the point that solar becomes cost-competitive with other energy sources seems always just out of reach, but as more of these possibilities crop up perhaps we will see the goal become reality soon. Two stories falling into such a category have cropped up in recent days.
First, a research group in Switzerland has increased the efficiency record for flexible cells made from what is known as CIGS — copper indium gallium selenide — from 17.6 percent to 18.7 percent. A minor upgrade, maybe, but it’s up from 14.1 percent as recently as 2005, and each tiny improvement brings the technology closer to mass adoption.
As the director of Empa, the Swiss Federal Laboratories for Materials and Technology, Gian-Luca Bona said in a press release: “Next, we need to transfer these innovations to industry for large scale production of low-cost solar modules to take off.” This is a key point — we often hear of efficiency improvements or conceptual designs in a laboratory, but bringing these technologies to the point where they can be mass produced is another phase altogether. Apparently, scientists at Empa are actually focused on that goal, working with a Swiss startup called Flisom to bring the thin-film solar cells to market.
And in less practical but potentially, possibly, in-a-few-years game-changing news, researchers at the University of Missouri have used what they call nantenna to create another flexible solar design that theoretically could provide — amazingly — 95 percent conversion efficiency. To be clear, this is in very early stages of development, and at first will only be capable of harvesting excess heat from industrial processes and the like. But as Missouri associate professor of chemical engineering said: “If successful, this product will put us orders of magnitudes ahead of the current solar energy technologies we have available to us today.”
Such statements do tend to give me pause, as there are any number of plans out there that will theoretically boost solar efficiencies into the stratosphere — like, say, this singlet fission idea, or these super thin-film cells that can bring 12-fold improvements. Of course, none of these have yet revolutionized solar power development. Hopefully, one or more of them will start that process soon.