Researchers at Oregon State University just made an energy breakthrough that could cut the cost of solar energy while also drastically reducing the carbon footprint of manufacturing solar materials. OSU chemical engineering professor Chih-Hung Chang published a paper in the journal RSC Advances that describes a way to make the sun a “one-stop shop” that produces both the materials for solar devices and the energy to power them.
From an environmental standpoint, solar energy is so vastly superior to fossil fuels it’s almost laughable. After all, sunlight is free – and harnessing it to create electricity produces no pollution. Well, almost no pollution. As skeptics love to point out, the manufacturing of solar materials often uses dirty energy. And there’s the question of how to properly dispose of these solar panels and cells when they’ve expired. Chang’s discovery could help the solar industry overcome these challenges once and for all.
Here’s how it works: Simulated sunlight is focused on a solar microreactor to rapidly heat it, while allowing precise control of temperature to aid the quality of the finished product. The microreactor produces a “continuous flow” of nanoparticle inks that make solar cells by printing. Existing approaches based mostly on batch operations are more time-consuming and costly. The light in these experiments was produced artificially, but the process could be done with direct sunlight, and at a fraction of the cost of current approaches.
“In these experiments, the solar materials were made with copper indium diselenide, but to lower material costs it might also be possible to use a compound such as copper zinc tin sulfide,” Chang said in an OSU press release. “And to make the process something that could work 24 hours a day, sunlight might initially be used to create molten salts that could later be used as an energy source for the manufacturing. This could provide more precise control of the processing temperature needed to create the solar energy materials.”
Using this process, Chang says it should be possible to synthesize highly-efficient thin film solar cells in minutes compared to other processes that might take 30 minutes to two hours. And that’s without any of the dirty energy consumption required by traditional manufacturing methods.
“Several aspects of this system should continue to reduce the cost of solar energy, and when widely used, our carbon footprint,” Chang said. “It could produce solar energy materials anywhere there’s an adequate solar resource, and in this chemical manufacturing process, there would be zero energy impact.”