By Brian Maffly
Some species of algae - yes, the green slimy stuff that accumulates on ponds - hold rich stores of oil, rendering them a source of alternative fuel. The growth on the surface, however, shades the algae beneath, thereby impeding biomass growth and thwarting algae's potential usefulness.
With USTAR funding, Utah State University has hired researchers to crack this problem so algae aquaculture can become a viable alternative to crude oil for the production of liquid motor fuels - an alternative that holds huge advantages over corn used in ethanol production.
"Look at the Midwest. We have food and fuel competing for the same natural resources, causing corn prices to go up and we're looking farther afield into less fertile land," says Jeff Muhs, an optics innovator recently hired from the Oak Ridge National Laboratory in Tennessee. USTAR's biofuels campaign joins elements from three USU colleges - agriculture, science and engineering - to address the alternative puzzle.
"To solve the problems of today, you need these different disciplines," says Ned Weinshenker, USU's vice president for strategic ventures and economic development.
"On biofuels, we want to focus on technologies that won't use existing food sources," he continues.
Joining Muhs on the biofuels research is Sridhar Viamajala, a chemical engineer USU recruited from the Department of Energy's National Renewable Energy Laboratory in Golden, Colo. Leveraging Viamajala's expertise in feedstock technologies, the team will identify the strains of algae with the best energy potential, then develop a growing media that speeds growth and maximizes oil content.
"In our layer designs, we're figuring out how to get the sunlight deeper into the algae through interesting optical approaches," Muhs says. "We can increase biomass. We're fielding inquiries one a day from companies interested in teaming with us."
To make this optics-based approach cost-effective, the team hopes to develop a use for the light not needed by the algae. Muhs is working on a two-step optical process that splits the spectrum, directing one stream to the algae and diverting the infrared spectrum - the longer waves beyond visible light - to photovoltaic devices for electrical generation.
This technology could offer a double benefit of reducing our dependence on fossil oil and curbing greenhouse emissions. The USU team's target is to achieve annual yields of 8,000 gallons of oil per acre. By contrast, a traditional crop such as soy yields only 100 gallons. According to one DOE projection, algae could replace all the petroleum consumed in the United States on an area not much larger than Maryland. With such potential, the field of algae fuels is catching fire.
"Our niche is an ability to manipulate the life systems of algae to improve yield and co-produce electricity," Muhs says.