Herald Tribune

 

Turning algae to oil

 

June 30, 2008

By Erica Gies

 

Algae, those simple, aquatic plants, are composed of carbohydrates, proteins and plant oil the algal oil can be processed into biodiesel or nonpetro-leun gasoline, the carbohydrdes into ethanol, and the protein into animal feed or human nutritional supple-ments.

The whole biomass can generate methane, which can be combusted to produce electricity. Processors can ex-tract chemicals to replace petrochemicals. As algae grows, it absorbs carbon dioxide. And it can be usei to clean sewage or agricultural or industrial runoff.

Micro algae, the simplest and most primitive plants, are generally more efficient converters of solar energy than terrestrial, plants and here a much higher energy potential. This possibility h lured entrepreneurs and venture, capitalists into the research fray.

Still, challenges loom large. Companies must grow algae biomass at a low enough cost to make ft worth processing, find a cost-effective way to separate the algae from water, extract something of value fro{ the algae and stabilize that .product to make it market ready, said Lissa  Morgenthaler-Jones, chief executive of LiveFuels,  an algae company based in Menlo Park, California.

Start-ups in the United States and elsewhere are investigating myriad processes and products derived from two basic models: closed or open systems.

Closed systems use photo bioreactors, clear containers that allow growers to carefully control the species and the environment They have been ex-,pensive to build and can suffer from" self-shading” if the algae grows to the point that it blocks out the sunlight that it needs to proliferate .

Open systems grow algae in ponds, raceways, or even h the wild. While less expensive to build, they are susceptible to invasion by other species and vulnerable to environmental changes.

LiveFuels uses open ponds to grow algae that are indigenous to the local environment, hoping that this will avoid the invasion problem. Since algae need nutrients to grow, including nitrogen and phosphorous, the company plans to feed agricultural runoff water.- polluted with nitrogen and phosphorous fertilizers - into its ponds, combining energy production with water treatment.

Another company, Bionavitas, of, Redmond, Washington, also grows native algae, but in deep, narrow canals, .with a special optical system to bring light to the algae beneath the surface. It too hopes to harness nutrients from polluted wastewater; and because' in-tense carbon dioxide inputs can speed growth; it envisages setting up sites next total factory that could funnel smokestack emissions directly into its canals. Michael Weaver, the chief executive, said that Bionavitas aimed to use "the whole algae" to produce biodiesel, ethanol, nutriceuticals and products currently derived from petroleum

Vertigro, a U.S. company based in Vancouver, Canada is testing single varieties of algae, grown in bioreactors that resemble hanging plastic bags, to see which grows best in a closed environment and produces the most oil. Its business plan is to sell its system to companies that would use it for commercial biofuel production, said Glen Kertz, chief executive of Valcent Products, a partner in Vertigro with Global Green Solutions, a sustainable energy development business.

In  Seattle, Blue Marble Energy is putting algal biomass in anaerobic digesters to produce industrial chemicals and methane. The latter is combusted in a turbine to generate electricity and could also be used in fuel cells, said the chief executive, Kelly Ogilvie. Saleable byproducts include ammonia, anhydrous ammonia, and other industrial chemicals currently made with petroleum.

Water cleanup is an important part of Blue Marble's business model. Its first demonstration plant, starting this year, will harvest nutrients from a Thaibrewery's effluent pond using native algae. In the future it hopes to work, with sewage treatment plants, mine sites or even the toxic marine algal blooms caused by agricultural runoff pollution. Harvesting these blooms, if possible, would help to repair the dam-aged ocean ecology.

All of these models will probably require inputs to adjust the balance nutrients and carbon dioxide. "You're going to be adding something," Morgenthaler-Jones said. "The only question is, what do you have to add and how much is it going to cost?"

Large-scale commercial production is at least five years away, according to algae most estimates, and it is still too early to say which methods, if any, will be economically viable, how much energy they may produce and what their effects on the environment might be.

They're so different that one really has to look at them one at a time to make sense of what they're promising,” said Jeremy Martin" a senior analyst with the Union of Concerned Scientists, an independent scientific policy organization"

The Union of Congress Scientists is interested in algae innovation but cautious about hype. Like anything that is promoted as a green energy source algae will have to prove its credentials. ”You have to add up all the pieces that it takes to make this into a fuel and do lifecycle accounting, ”Martin said.

He dismissed, for example, the notion that harvesting carbon dioxide from smokestacks would offer an additional environmental benefit. ”Any plant used to make fuel uses recycled carbon dioxide, ”he said .”Whether you recycle it on it’s way out of a   smokestack or straight from the atmosphere, like a plant growing in a field somewhere, it’s still the same carbon recycling.”

Martin also questioned whether companies could find the ingredients  they would need –water, sunlight, nutrients, carbon dioxide-in close proximity and in quantities large enough to generate  a meaningful amount of fuel.

But Darzins, of the National Renewable   Energy Laboratory ,said, ”whenever  you try to harness biology ,it’s never an easy thing. ”He added that the laboratory was “bullish” on algae.

So, too, was Morgenthaler-Jones of LiveFuels.”Our team looked at hydrogen, solar power, ethanol,” she said. ”It’s only when we got to algae that we said, ’this one is going to be really hard, but it could work. And if it works, it has the potential to change the world..”

The union of Concerned Scientists counsels balance. It says no single material is likely to meet global fuel needs without having an effect on the environment.

Reducing pollution from transportation fuels, moreover, is only part of the puzzle, which also includes improving energy efficiently and reducing the number of miles that people drive.

“As exciting as these developments are,” Martin  said ,”we don’t see any likelihood that there’ll be so much algae that it will reduce the need to do these other things