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Arctic Leaf

Can algae be the next biofuel?

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The lure of the oceans has always had a special appeal for advocates of biofuel. The vast reaches of the deep speak of a promise that unlimited amounts of space will be able to bring forth completely sustainable forms of energy.

“Two-thirds of the globe is covered with water,” says Khanh-Quang Tran, a Norwegian researcher who has published papers on the possibility of growing algae as a biofuel on an industrial basis. “If we used only a tiny portion of that space, we’d have enough to supply ourselves with all the fuel we needed.”

Of particular interest to researchers is one species, laminaria sacceyarina (“sugar kelp”), which grows along the coast of many countries, including Scandinavia. It is the “seaweed” that seems to be a flower but is actually all one undifferentiated cellular structure that takes on various forms in competing for sunlight. As the name implies, it contains lots of sugar – three times as much as the sugar beet. Scandinavian scientists have been especially intent on harvesting this plant for food and fuel use.

“It’s actually regarded as a nuisance, since it grows everywhere and clogs the beaches,” says Fredrik Grondahl, a researcher at the KTH Royal Institute of Technology in Sweden who heads the Seafarm project. “But it absorbs nitrogen out of the water, effectively as a wastewater treatment plant. It’s regarded as an environmental problem, but it’s actually a valuable resource.”

The big question will be this: Can a weed that grows so prolifically in the sea be domesticated so that it can grow in large quantities under controlled conditions?

Sweden and Norway seem to have taken the lead on this project, mainly because of their long coastlines, where the algae grows intensely in a cold climate. The Seafarm project involves  growing underwater algae farms on ropes. The team collects excess algae from the Baltic Sea and cultivates it as food and fuel. One technique is called the “sporophyte factory farm.” The algae spores are sown onto ropes. They sink and grow in the sea. In about six months, they have grown onto the ropes and are harvested and processed on land covering two hectares. From there it can be converted to eco-friendly food, medicine, plastics and energy fuels such as methanol. The city of Trelleborg, where the farm is located, estimates that 2.8 million liters of fuel can be extracted from its algae resources.

Kahnh-Quang Tran of Norway has been following another line of research. He mixes a slurry of kelp biomass and water and heats it rapidly to 350 degrees Centigrade. Tran says the fast hydrothermal liquefaction gives him a product that is 79 percent bio-oil. A similar experiment on the U.K. was only able to produce 19 percent oil, but Tran claims that the rapid heating improves the process tremendously. “What we are trying to do it mimic the natural process that produces oil,” he said. “Whereas it takes geological time in nature to produce oil, we can do it in a matter of minutes.”

Tran is now looking for partners who can help him move up to an industrial scale.

Another plan developed in France and the Netherlands is to line highways with algae pools in the hope that they will immediately absorb the carbon exhaust that comes from automobiles. This will remove CO2 from the atmosphere and recycle the fuel as well. An experimental installation was demonstrated at the summer garden festival at Genève Villes et Champs this year.

Another country that is experimenting with algae is Australia. This October, the Muradel Corporation opened a $101. 7 million demonstration plant in Whyalla designed to produce 30,000 liters of green crude every year. The company is employing its Greeen2Black technology, designed to produce a continuous stream of environmentally sustainable crude equivalent.

Muradel CEO and University of Adelaide Associate Professor David Lewis said if the demonstration plant were successfully scaled to a commercial plant, it would produce 500,000 barrels of refinable green crude a year by 2019 – enough petrol and diesel to fuel 30,000 vehicles for a year. The planned 1,000-hectare commercial plant would create at least 100 new skilled jobs in the Whyalla region.

“This is world-leading technology which can be scaled up exponentially to help steer our fossil fuel-dependent economy toward a more sustainable future,” Lewis said.

Not everyone is enthusiastic about algae. “It will take anywhere from 5 to 15 years to produce on a scale that would be meaningful to the nation’s every needs,” says Jim Rekoske, general manager of Honeywell’s UOP division. He likened it to trying to maintain the water balance in a fish tank.

“You have to have just the right temperature and the right amount of carbon dioxide to get these growth spurts,” he said. Algae farms are also very susceptible to invasive species and have to be monitored constantly. Still, an acre of algae can ideally produce 15,000 gallons of biofuel per year, as opposed to only 420 gallons per acre from corn ethanol. “We could replace all the diesel we consume now on half of 1 percent of our current farmland,” says Douglas Henston, CEO of Solix Biosystems of Fort Collins, Colo. Solix is supplying the military with biofuels at a whopping $33 per gallon.

So, will algae make the same progress in the United State that it seems to be making in Sweden and Norway? American researchers may take up the challenge as well. The long coastal lines are not there to tempt us, but research breakthroughs may finally make algae biofuels more practical and economically viable everywhere.

Arctic Leaf

Can algae become the new biodiesel?

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Supporters call it “clean diesel” to differentiate it from “biodiesel,” and indeed, there is a difference. Soybeans, the main feedstock for biodiesel, have only a 2-3 percent oil content. Some species of algae can have up to 60 percent oil content. This reduces the land requirements for growing a crop by a factor of 30.

So is algae biodiesel one of those great ideas that is always just over the horizon? Or has it germinated long enough that it may finally about to become a reality? The outcome still appears to be up for grabs.

The term “algae” actually cover a whole spectrum of organisms, from the 20-foot ribbon-like “seaweed” that grows in ponds and along littoral shores to the mid-ocean, microscopic “plankton” that is the diet of whales. All have one thing in common – they use carbon and sunlight to photosynthesize organic material. And they are good at it. Some species can double their mass within 24 hours. Thousands of species thrive in varying environments. Last summer, a red algae “tide” that feeds on farm runoff at the mouth of the Mississippi River “bloomed” to cover 5,000 square miles of the Gulf of Mexico, killing all manner of birds, fish and marine life, including hundreds of manatees. “If we can figure out how to make energy out of that,” President Obama told an audience at the University of Miami, “we’ll be doing alright.”

The idea of harvesting algae for energy was first suggested by Richard Harder and Hans von Witsch, two European scientists at the outbreak of World War II. Nothing much developed, however, and interest didn’t revive until the Energy Crisis of the 1970s, when the Department of Energy set up an Aquatic Species Program to pursue research.

Funded with $25 million over the next 18 years, the Aquatic Program investigated thousands of species, finding the Chlorella genus the most promising. It also made an important discovery. When Chlorella is deprived of nitrogen, it can increase its lipid (fat and oil) content to a remarkable 70 percent of mass! Remember, soybeans are only 2-3 percent lipids. But this created a conundrum. While depriving algae of nitrogen might may increase lipid content, it also severely inhibited growth. The Aquatic Program had not yet resolved this dilemma when it was disbanded in 1996.

Private companies picked up the research, however, and have tried to overcome it with genetic engineering. While pursuing this, they have developed two methods of cultivation. The easiest is to grow algae in open pools or “raceways” that devour large areas of land, since sunlight can only penetrate a few centimeters into the algal mat. The problem here is that most species are highly sensitive to variations in acidify, temperature and humidity. Their high lipid content also means they synthesize fewer proteins, which makes them extremely vulnerable to invasive species. This makes it very difficult to bring them up to commercial scale.

The more advanced technology is “photobioreactors,” conducted in large networks of glass or plastic tubes. The system overcomes environmental difficulties but is very expensive. In 2009 Exxon combined with J. Craig Venter, the decoder of the human genome, to try to develop a commercial method for developing algae-based fuels. After investing $600 million, however, Exxon pulled out of the enterprise in 2013, saying commercialization was 25 years away.

Nevertheless, several small companies say they are now making progress. Algenol, a Fort Myers, Fla. company, says it has developed a revolutionary “3rd generation” technology that can produce ethanol, jet and diesel fuel 8,000 gallons per acre, 18 times the output of corn-based ethanol, at $1.25 per gallon. Sapphire, a San Francisco company, has opened a 100-acre Green Crude Farm in New Mexico and hopes to be producing 100 barrels a day next year with full-scale commercialization by 2018. And Aurora Algae, a Hayward, Calif. firm which has operated a test facility in Western Australia for the last three years, has just announced an open-pond operation in Harlingen, Texas that it hopes to expand to 100 acres.

There is one great irony to all this. A full-blown algae industry already exists, providing feedstock for food additives, cattle silage and nutritional and pharmaceutical products. Some highly specialized fatty acids derived from exotic species can fetch $10,000 per gallon. In fact, the current industry sees algae-for-fuel as a rather low-grade use. “Until more federal funding is available, my members are going to continue growing for the higher-value products,” Barry Cohen, executive director of the National Algae Association, told Slate’s John Upton. “We have algae companies that are growing for the ingredients industry, the food industry and the nutraceutical industries. If they can grow the right species, those companies will buy every drop they can make.”

What makes these operations viable, of course, is their high-value end products, which cover the costs of growing algae in commercial quantities. An algae-for-fuel industry will either have to: a) develop new species that are much more efficient or b) perfect mass-production techniques that can bring prices down to an acceptable range. Only then will “clean diesel” become a competitor. For now, the industry seems headed in the right direction.