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Algae: a fuel source for the future? Entrepreneurs seek ways to commercialize the use of tiny organisms that devour carbon dioxide to produce feedstock for biofuels Alan Bailey Petroleum News
A July 14 announcement by oil giant ExxonMobil that it plans to form an alliance with biotech company Synthetic Genomics, to invest more than $600 million in biofuel generation from algae, has turned the spotlight on a technology that had perhaps until then remained somewhat in the shadow of more developed biofuels such as corn ethanol. But, with controversy surrounding the impact of ethanol production on food prices, and questions over the net carbon footprint of the ethanol industry, what is the potential for the use of algae as an alternative fuel source?
On Aug. 3 Mary Rosenthal, executive director of the Algal Biomass Organization, and John Williams, the organization’s public relations consultant, explained to Petroleum News some of the ins and outs of the fledgling algal biomass industry. The Algal Biomass Organization is a nonprofit corporation with a mission of facilitating the commercialization of microalgae biomass for biofuels production and greenhouse gas abatement.
High yields Thanks to the typically high growth rates of algal organisms, the yield per acre of oil from algae production could be between 2,000 and 6,000 gallons per year, compared with perhaps 60 gallons per acre from soybeans or 200 gallons per acre for palm-based oil, Williams said.
“So we’re talking orders of magnitude more oil per acre,” he said.
And those high yields result in part from the ability to grow algae continuously, rather than using the seasonal cycle of planting and harvesting of a traditional crop.
“You don’t have the growing season, the planting, the harvesting etc. … You have the opportunity to continuously grow algae on a regular basis,” Rosenthal said. “So, the yield per acre mathematically will be significantly better than seasonal crops.”
Carbon dioxide And high growth rates are stimulated by feeding carbon dioxide to the algae, bubbling the gas through water in which the algae are growing and thus enabling the additional benefit of using algae as a route for recycling carbon as fuel or, perhaps, sequestering the carbon as useful plastics — algae use photosynthesis to convert carbon dioxide into oxygen and carbon-based products such as oils.
“Algae love carbon. That’s how they grow,” Williams said. “The more carbon that they’re exposed to, the faster that they can grow.”
Then, given the ability of algae to gobble up organic waste or farm nutrients, and to thrive in brackish water, the potential exists for the added benefits of using and cleaning water that would otherwise be useless. Algae do not require potable quality water, Williams emphasized.
“If you had a perfect place to set up an algae farm it would be next to a coal-fired plant alongside a river that’s downstream from massive agricultural operations, where you have a significant fertilizer runoff,” Williams said.
The potential benefits of industrial algae production have triggered a cascade of international entrepreneurial activity and inventiveness, researching and developing solutions to the various technical challenges that the youthful algal biomass industry faces, Rosenthal said. The Algal Biomass Organization anticipates nearly a thousand people from industry, government agencies and academia will attend its third annual Algae Biomass Summit in San Diego in October, she said.
Three issues Algal biomass research and development targets three main issues: determining which of the up to 50,000 known strains of algae are most suitable for industrial use; designing and evaluating different approaches to algae production and harvesting; and working out how to process the algae products, Williams said.
When it comes to selecting suitable algae, some of the key sought-after features are speed of growth and the production of appropriate types of oil, suitable for processing into biofuels. And one strand of algae digests sugars rather than using sunlight for growth.
“There’s a ton of research … just at picking the right algae strains to work with as your feedstock,” Williams said.
The most promising avenue for growing the algae for fuel or plastics is the pond or canal, open to the sunlight, but perhaps with some form of protective bag or cover to prevent contamination of the algae strain being used, Williams said. Another possible technology, known as a photo bioreactor, involving the irradiation of enclosed, algae-spiked water with artificial light, tends to be expensive to operate but has been in use for some time for the production of small volumes of high-value algal products for the food supplement market, he said.
And operational algae production facilities are starting to appear, at least in pre-commercial form. For example, in July Solix Biofuels started up a first-of-a-kind two-acre demonstration facility in Colorado, growing oil-producing algae in water and carbon dioxide produced as waste from a neighboring coalbed methane facility. Solix is fleshing out the engineering aspects of algal fuel production, with the eventual aim of developing a large commercial-scale facility, Solix CEO Doug Henston told Petroleum News Aug. 5.
“You have to understand the operating protocols associated with this industry and that’s essentially what we’re doing right now,” Henston said.
Ethanol or oil Fuel production from algae can follow two distinct routes: ethanol production and oil production, Williams said.
Ethanol is produced by fermentation using enzymes. One company in this field, Algenol Biofuels, says that its proprietary process uses algae that incorporate the appropriate enzymes, thus producing ethanol concurrently with algal growth and turning out 6,000 gallons of ethanol per acre per year, with the potential of future production rates up to 20,000 gallons per acre.
Oil, a natural product of some algae strains, offers several possible routes to fuel production, including a well-established process called transesterification for making biodiesel.
One company, Honeywell subsidiary UOP, has partnered with oil giant Eni to develop a proprietary process called Ecofining to convert vegetable oil into “green diesel” or jet fuel. Eni and Galp Energia plan to start up Ecofining plants in Italy and Spain in 2010, according to the UOP Web site.
Meantime the embryonic industry in algal biomass is moving ahead, seeking ways to achieve commercial fuel production, with viability depending on the development of algae types and production techniques that result in large-scale fuel output from manageable areas of land. And that land, while not needing to be of agricultural quality, will likely have to be in locations with adequate sunlight and sources of water and carbon dioxide.
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