Could algae be the next alternative fuel?

Thursday, July 24, 2008

You know that greenish tinge in parts of the lake this season? The same one that shows up in the swimming pool when you run out of chlorine - or in our fish tank if the filter shuts down?

What if you could use that to run your car?

Some researchers believe that's possible. And the state is considering a proposal from Maharishi University of Management to create an algae bioreactor.

It's a fancy name for a concept that is really quite simple, and it has several potential advantages. Algae use photosynthesis to live. That's the same basic process as other plants like trees and grass. The key is chlorophyll, a green pigment that drives the reaction.

Photosynthesis uses light to produce energy for the plant and also strips carbon dioxide from the atmosphere. Oxygen is a byproduct. An algae farm uses photosynthesis to scrub the atmosphere. Algae grows fast, so projects based on it can expand rapidly.

And there are some industrial applications already being tested. Some power plants are using algae farms to strip out emissions, since the hot, carbon dioxide-laden gases are a banquet for the tiny plants. Other scientists are looking at using algae as a food supply in areas that crops won't easily grow.

But none of this, including your cloudy fish tank, is producing oil. What's missing? MUM Professor Lonnie Gamble says he has the answer. It's not about what the algae produce; it's about what the algae is.

"It turns out that the bodies of algae are about 50 percent oil. We can make fuel from them," he said.

It's possible to refine the oil into biofuel that can then power vehicles. The Iowa MUM project is partnering with Valcent, a Texas-based company, to examine the potential for beginning a university bioreactor to produce and refine the algae.

The current efforts are laboratory scale. The university wants to expand that to a quarter-acre greenhouse for the algae as a test site. Researchers believe industrial scale production will require sites of at least 100 acres.

Assistant Professor Jimmy Sinton directs the bioreactor project. He said the key for future use of algae is that the plant is not difficult to grow, nor is it difficult to understand.

The Iowa Power Fund will give money to the project, though it's not yet clear how much. The original request was $2 million, but negotiations have not set the final amount.

The question is whether the process is in itself fuel efficient. There's no net benefit if it takes more power to produce the algae biofuel than you get in return.

The good news is that it doesn't take much to grow the algae. Some algae farms use gas vented from smokestacks as food for the algae. Sinton is not planning to use that process for his algae. Geothermal heat and passive sunlight are enough, particularly on the small scale currently being planned.

Algae farmers don't need much space, either. Rooftop farms are possible, and urban production is viable in the long term.

Both Gamble and Sinton say the process is close to carbon neutral. That means it produces as much carbon as a fuel as it removes while it grows. It's a trade-off.

But expanded use of the algae can make it carbon negative. Sinton pointed to algae as a building material as an example of how producers can sequester carbon and keep it out of the atmosphere on a long-term basis.

Money is a driving factor for the research. The process works. But the money-saving advances haven't come in yet. Sinton's current estimates are that setup will cost $300,000 per acre. That number will fall as researchers learn how best to use materials.

That's a lot, but the payoffs are big as well. Sinton put production at 30,000 gallons per acre per year at the trial stage. Full-scale production could produce as much as 600,000 gallons per acre per year.

As with everything, research should find ways to lower the production costs and raise profits.

"We're focused particularly on how to produce cost-effective biodiesel," Sinton said. "The answers are all there. Nobody's put them all together."

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