Are Solar Panels More Efficient Than Plants?

A recent study found that current solar technology is more efficient at transforming sunlight into energy than plants.

Biomimicry is basically the practice of observing processes in nature, and copying Mother Earth’s strategy for efficiency and waste reduction. In an interesting twist, however, an article published in the May edition of Science found that photovoltaic-driven electrolysis is the more efficient process compared with photosynthesis and measured on an annual basis.

But, say some scientists, it’s almost impossible to compare the two processes on a level playing field:

“Plants are less efficient at capturing the energy in sunlight than solar cells mostly because they have too much evolutionary baggage,” say researchers at Michigan State University. “Plants have to power a living thing, whereas solar cells only have to send electricity down a wire. This is a big difference because if photosynthesis makes a mistake, it makes toxic byproducts that kill the organism. Photosynthesis has to be conservative to avoid killing the organisms it powers.”

Just as important as efficiency are life-cycle costs—the capital cost and valuation of the environmental impact of a product from its creation to its destruction. It would be hard to argue that man’s process of producing, installing, repairing and recycling of a home solar system is anywhere near as benign as the sprouting, blooming, and eventual composting of a wild plant.

David Kramer, a professor of photosynthesis and bioenergetics at Michigan State University says that for a true comparison, plants that package the sun’s energy in handy little stored-fuel vessels (carbon-based molecules) should be compared not to solar cells that just take the first step of converting the sun’s energy to jazzed-up electrons, but to solar cell arrays that also store energy in chemical bonds.

Article by Beth Buczynski, appearing courtesy Crisp Green.