Algae Production Assessment Seeks to Lower Costs

Two Kansas State University engineers are assessing systematic production methods that could make the costs of algae oil production more reasonable, helping move the United States from fossil fuel dependency to renewable energy replacements.

The idea, by K-State's Wenqiao "Wayne" Yuan and Zhijian "Z.J." Pei, is to grow algae in the ocean on very large, supporting platforms. The National Science Foundation awarded a $98,560 Small Grant for Exploratory Research in 2009 for their work.

Compared to soybeans that produce 50 gallons of oil an acre a year, some algae can average 6,000 gallons ─ but it's not cheap to produce. Current algae growing methods use ponds and bioreactor columns, and algae float around suspended in water. Harvesting such a moving target systematically requires using costly inputs like centrifuges and electricity. Even with these best technologies for algae growth and production, the end product biodiesel is expensive at about $56 a gallon.

Yuan, assistant professor of biological and agricultural engineering at K-State, thinks it will be five to 10 years scientists before understand the fundamentals of large-scale algae production sufficiently that cost can be reduced to the target of about $5 a gallon.

"It will take that much time to really understand the fundamentals of large-scale algae production and to establish pilot projects," he said.

Both Yuan and Pei, professor of industrial and manufacturing systems engineering at K-State, think food production land should not be used to produce algae for fuel. The two are studying the feasibility of large-scale algae production in the ocean and how to engineer the production systems.

Pei and Yuan are working to identify oil-rich algae species that are inclined to settle down and grow en masse on a solid surface, a characteristic that will make algae production manageable and harvesting much simpler.

"We think there is tremendous potential for algae oil production if we grow it on big platforms and incorporate the ocean into the system," Yuan said. Half the cost of growing algae is in providing a steady supply of food and water, the growth medium. Ocean water offers those in abundance, he said.

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