Washington, August 20 : A team of researchers from the University of Virginia in the US is trying to determine exactly how promising algae biofuel production can be by tweaking the inputs of carbon dioxide and organic matter to increase algae oil yields.
According to a report in ENN (Environmental News Network), algae are tiny biological factories that use photosynthesis to transform carbon dioxide and sunlight into energy so efficiently that they can double their weight several times a day.
As part of the photosynthesis process algae produce oil and can generate 15 times more oil per acre than other plants used for biofuels, such as corn and switchgrass.
Algae can grow in salt water, freshwater or even contaminated water, at sea or in ponds, and on land not suitable for food production.
On top of those advantages, algae - at least in theory - should grow even better when fed extra carbon dioxide (the main greenhouse gas) and organic material like sewage. If so, algae could produce biofuel while cleaning up other problems.
"We have to prove these two things to show that we really are getting a free lunch," said Lisa Colosi, a professor of civil and environmental engineering who is part of an interdisciplinary University of Virginia research team, recently funded by a new U.Va. Collaborative Sustainable Energy Seed Grant worth about 30,000 dollars.
With the grant, the team will try to determine exactly how promising algae biofuel production can be by tweaking the inputs of carbon dioxide and organic matter to increase algae oil yields.
According to Colosi, most previous and current research on algae biofuel has used the algae in a manner similar to its natural state - essentially letting it grow in water with just the naturally occurring inputs of atmospheric carbon dioxide and sunlight.
This approach results in a rather low yield of oil - about 1 percent by weight of the algae.
"The U.Va. team hypothesizes that feeding the algae more carbon dioxide and organic material could boost the oil yield to as much as 40 percent by weight," Colosi said.
Proving that the algae can thrive with increased inputs of either carbon dioxide or untreated sewage solids will confirm its industrial ecology possibilities - to help with wastewater treatment, where dealing with solids is one of the most expensive challenges, or to reduce emissions of carbon dioxide, such as coal power-plant flue gas, which contains about 10 to 30 times as much carbon dioxide as normal air.
"Published evidence of improved algae oil output might spur significant follow-up efforts by public and private sectors, since the fundamentals of this technology are so appealing," said Colosi.