Algae is more than just pond scum.
It's a potential power source. The green glop that forms in fetid pools and in nutrient soaked ground fed by overflowing septic systems increasingly is being investigated for properties beyond the "ugh" factor.
At Stanford University, a team of scientists has figured a way to extract a tiny portion of electrical current from algae cells. Gwyneth Dickey at the Stanford News Service wrote that the team was "able to draw from each cell just one picoampere, an amount of electricity so tiny that they would need a trillion cells photosynthesizing for one hour just to equal the amount of energy stored in a AA battery."
The power comes from photosynthesis, the process through which a plant converts sunlight to energy.
Dickey quoted WonHyoung Ryu, the lead author of the paper published in the March issue of Nano Letters, as saying he believes the Stanford team is the first to extract electrons from living plant cells. However, Ryu said there is a long way to go to put such power generation to any commercial use. "We're still in the scientific stages," he said.
However, in Nano Letters, he offered a more effusive account: "This result may represent an initial step in generating 'high efficiency' bioelectricity by directly harvesting high energy photosynthetic electrons."
University of California, Merced graduate student Patrick Wiley is also investigating the power potential of algae.
Wiley will work in Santa Cruz cultivating algae in ocean-floating bags and with a University of California, Berkeley group also developing ways to generate power with algae.
Here's what Elliott told us in a past post: "The synergistic opportunity that is most apparent to me for the Valley is between wastewater and algae biofuels. Finding cost-effective ways to produce algae biofuels is a real challenge. The San Joaquin Valley may be a good place to think about economic solutions where existing algae wastewater ponds can be combined with algae biofuels production."
And Boulder, Colo.-based Pike Research said algae is among the substances being investigated with "significant investments" for commercial production of cellulosic ethanol.
Research into algae, especially as it relates to biofuels, has been going on for years and is expected to continue. UC Berkeley Professor Kris Niyogi said the amount of energy required to produce fuel from algae is an important question, as it is for any type of alternative energy.
"Inevitably, there are going to be energy inputs that are necessary to produce a fuel from algae, just as there are for other biofuels, such as corn ethanol," he said in an interview with Nova on PBS. "For algae, energy will be needed to build the ponds or photobioreactors, to mix the water and provide carbon dioxide and other nutrients, to harvest and concentrate the algal cells from large volumes of water, and to make and transport the biodiesel product.
"I don't think there is a clear answer yet for algae. A lot of engineers are hard at work trying to minimize the energy inputs and maximize the net energy output."
Photo: Courtesy Wilson Lab at Auburn University.
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