The idea of a biological solar cell isn’t new. Look at a leaf, or the algae scum on a pond. But the effort to harness photosynthesis to create energy humans can use is an intricate process that presents a number of hurdles.
Binghamton junior Yudi Pardo works on one of the first hurdles: taking the photosynthetic engine out of a plant cell and putting it somewhere it can be used. It’s a problem he has been examining for nearly five years — since before he received his high school diploma.
Now, as a bioengineering major working in Assistant Professor Gretchen Mahler’s laboratory, he’s taking advantage of his opportunities.
He’s working with cyanobacteria ― essentially a blue-green algae — seeking a way to harvest its photosynthetic thylakoids. “How do I extract the complexes in a way where they won’t degrade over time?” he asks.
The solution, eventually, is to graft the thylakoids, which reside in the cell’s inner membrane, onto the cell’s outer membrane. “So when the outer membrane flakes off, you have a working photo system,” he says. “There’s a lot of genetic manipulation.”
Mahler sometimes has difficulty mentoring him, because bio-energy isn’t her research focus. “A lot of students don’t realize they’re into research so early,” Mahler says, much less develop such a specific interest. “He came to me with the project.”
“It’s an interesting problem,” she says, “That’s a good area of research. Nobody has done it.”
It’s an area of research with useful implications. Nathan Nelson of the University of Tel Aviv has developed an ultra-small working solar cell based on a pea plant; it generates 10 volts and with 20 percent efficiency is moderately more efficient than current silicon-based cells.
Nelson and Pardo understand some parts of a plant’s photosynthetic engine are 95 percent to nearly 100 percent efficient. If those parts can be harnessed properly, it could lead to great advances in bio-solar cell efficiency — enough to make them cost effective.
“If we can bring that to the entire device, that would make solar technology more viable for people,” Pardo says. “That really high efficiency on a small scale is what drew me in.”
Biological cells would be faster to construct and largely carbon neutral, although questions remain about how durable biological cells would be, and how they would distribute their energy.
But Pardo, who’s just 20 years old, has time to answer them. “I don’t know specifically where I want to go with this,” he says, citing interests in bio-medicine and medical instrumentation. “But alternative energy has always been at the top of my list.”