Plants can overcome their evolutionary legacies to become much better at using biological photosynthesis to produce energy, the kind of energy that can power vehicles in the near future, an all-star collection of biologists, physicists, photochemists, and solar scientists has found.
A U.S. Department of Energy (DOE) workshop that drew a prestigious collection of 18 scientists to compare the efficiency of plants and photovoltaic solar cells led to an important and provocative scholarly article in today's issue of the journal Science. Two of the scientists are from DOE's National Renewable Energy Laboratory (NREL), Arthur J. Nozik and Maria Ghirardi,
Titled "Comparing Photosynthetic and Photovoltaic Efficiencies and Recognizing the Potential for Improvement," (LINK HERE) the article combines lessons learned from evolutionary photobiology and modern solar cells to make the case for a potentially huge boost in the efficiency of the solar production of biofuels.
The multi-junction tandem solar cell initially developed at NREL proved to be an important strategy to understand how to boost the efficiency of corn, grasses, algae, and other plants that use photosynthesis to produce stored solar energy.
The annually averaged efficiency of photovoltaic electrolysis based on silicon semiconductors to produce fuel in the form of hydrogen is about 10 percent, while a plant's annually averaged efficiency using photosynthesis to form biomass for fuel is about 1 or 2 percent.
Plants, following the path of evolution, are primarily interested in reproducing and repairing themselves. The efficiency at which they produce stored solar energy in biomass is secondary.
Still, things can change.
Just as early Native Americans manipulated skinny, non-nutritious Teosinte into fat, juicy kernel corn, today's plants can be manipulated to become much better sources of energy.
Nozik, a NREL senior research fellow,
|Contact: Bill Scanlon|
DOE/National Renewable Energy Laboratory