17 January 2008

Dusting off research: Algae to fuel

That slippery brown and green glop people slip on when wading a river, may soon help power vehicles.

Drivers cannot pump algal fuel into their gas tanks yet, but Keith Cooksey, a microbiologist at Montana State University thinks the idea holds promise. Cooksey is one of quite a few U.S. scientists that studied the feasibility of turning algal oil into biodiesel in the 1980s. However, funding for the research dried up, and the idea went on the back shelf.

A few months ago, however, Cooksey started getting phone calls and e-mails from researchers and others who read about his algal work, and it was back to the lab.

Still interested in pursuing algal fuel, Cooksey said his lab in the 1980s figured out how to increase oil production from algae. It developed a system that screened algae for their oil content and greatly reduced the sample size needed for their research. It developed a stain for algae, called Nile Red. When treated with the stain, the algae became fluorescent under certain conditions, making it easier to measure their oil content.

Algae grow naturally along rivers, the seashore, and in the mangrove swamps of southern Florida, Cooksey said. They also grow in wastewater treatment ponds and can grow commercially in manmade ponds. One design they tested in the 1980s was a shallow pond that looks like a raceway. Another is a system of deeper ponds. Algae can grow very well in desert states that have plenty of sunshine and access to water unusable for traditional agriculture or drinking. Because of its salt content, salt water is more economical than fresh water for growing algae, so southwestern states with saline aquifers might find it easy to grow them.

“In principle, lipids from microalgae are suitable for refining into conventional liquid fuels,” said a 1983 annual report from the Solar Energy Research Institute that provided Cooksey’s funding and some algal cultures. “Indeed, in the past, biological oils have been refined to fuels during shortages in petroleum supply.”

Joseph LaStella, president of Green Star Products, Inc. in San Diego, Calif., built a demonstration pond in Hamilton, Mont., last spring.

Soybeans produce about 50 gallons of oil per acre per year, and canola produces about 130, LaStella said. Algae, however, produces about 4,000 gallons per acre a year, and he predicted it will go far beyond that. He said algae require only sunshine and non-drinkable water to grow. The demonstration pond showed algae will grow even when temperatures fall below zero.

“This is the only answer to our fuel crisis,” LaStella said.

David Tooke, director of operations at Sustainable Systems in Missoula, said, “With new interest in biofuels, it’s another opportunity to supply those fuels.

“As far as surface area needed, it’s more reasonable to assume we could attain those levels of production from algae versus agricultural crops,” Tooke said. “It’s beginning to make sense to pursue this again.”

For related information, go to www.isa.org/manufacturing_automation.