Researchers studying solar science are peering inside their sandwiches for answers on how to improve photovoltaic technology. Plants process sunlight far more effectively than we do; lessons from nature could be a big step in designing the next generation of solar panels.
David Cliffel and Kate Jennings, two researchers from Vanderbilt University have applied a plant protein called Photosystem 1 (PS1) to silicon, resulting in a ‘biohybrid’ cell that, according to Cliffel, “produces current levels almost 1,000 times higher than… various types of metals. It also produces a modest increase in voltage.” The team has not yet turned this solar salad into a functioning solar panel, but Cliffel says, “we could reach the range of mature solar conversion technologies in three years.”
At the National Sustainable Design Expo, Jennings won an Environmental Protection Agency award that will enable the team to build a prototype solar cell. The potential advantages of the biohybrid are increased longevity and reduction in cost:
- Ask anyone who eats their greens - spinach costs less than platinum, one material often used in PV panels.
- The researchers' PS1 cell did not show any of the usual signs of deterioration throughout the nine month research period. Cliffel says, “Nature knows how to do this extremely well. In evergreen trees, for example. PS1 lasts for years. We just have to figure out how to do it ourselves.”
The research has been published in the journal Advanced Materials, where science is explained in detail. Here’s an excerpt to give an idea of how the charge is created:
“When a PS1 protein is exposed to light, it absorbs the energy in the photons and uses it to free electrons and transport them to one side of the protein. This creates regions of positive charge, called holes, which move to the opposite side of the protein…”
This ‘Popeye panel’ is the latest example of solar research learning from nature: earlier this year there was a lot of news attention on a new design for solar panels that track the course of the sun through the sky, imitating sunflowers.
