Biofuels or Bust
Algae show enormous potential as a biofuel feedstock, prompting numerous companies to further develop production and conversion systems. But some researchers remain skeptical as large-scale commercialization of reliable processes seems a distant goal.
"I think this is the year of the pilots," says Riggs Eckelberry, president and CEO of California-based OriginOil Inc. The company is one of several working to optimize algae production for biofuels and while Eckelberry recognizes that widespread production and competition with petroleum is 20 to 25 years away, he believes 2011 will bring about the first small-scale commercial systems.
"Scaling up will require time," he says. "It's a lot of brick and mortar. I still see scale, commercial programs at three to five years out. I think 2011 is going to be a very good year for showing that we've got commercial systems." Demand from existing infrastructure including CO2 emitters such as ethanol plants and biorefineries represents the low-hanging fruit for algae production. Cultivation systems can be attached to those polluters and function as a blended revenue stream, as it is not at the mercy of fuel commodity prices. "Before algae become as big as petroleum, we'll have lots of algae being used beneficially to suck up CO2 and create local energy that can be consumed on the premises," he says. "Algae production will be local. It will not be centralized."
The Home Run for Algae
Co-locating algae ponds at wastewater treatment plants would allow larger-scale growth, while providing more money to the plants, along with benefits such as waste energy, CO2 absorption and nutrient cleaning. "The fact is, wastewater is the home run for algae," Eckelberry says, adding that it provides the most bang for the buck currently. Cultivating algae in a wastewater environment is 20 percent more profitable than other processes, he says. "Wastewater treatment plants have lots of nutrients," he says. "So algae solves the problem by eliminating the denitrification stage."
Researchers at the University of Virginia recommended co-location with wastewater treatment plants in a recent study, "Environmental Life Cycle Comparison of Algae to Other Bioenergy Feedstocks." Published in Environmental Science & Technology, the report found that algae cultivation (excluding conversion) consumes more energy, has higher greenhouse gas (GHG) emissions and uses more water than switchgrass, canola and corn. That environmental footprint, researchers concluded, comes primarily from upstream impacts such as CO2 demand and fertilizer, two major barriers to commercial and widespread production that can be alleviated by co-location at wastewater treatment plants or other areas that emit CO2.
"We were surprised by what we found initially," says Andres Clarens, assistant professor at the university's civil and environmental engineering department and lead author of the paper. "At the end of the day, the main conclusions here were that algae cultivation, at least as it's envisioned or was envisioned for much of the '90s and recently, in terms of open ponds, has a big environmental footprint." But terrestrial crop production has improved greatly with experience in the past 100 years and so can algae growth. "It's a pretty clear upward trend," Clarens says of other crops, such as corn. "I think we're standing at the bottom of that hill with algae."
The message of the paper is there's some low-hanging fruit in algae production, Clarens says. "If we're serious about algae, we need to find a way to get nutrients from other sources, other than just dumping bags of fertilizer into the pond," he says. "That's never going to be a winner from the environmental standpoint and probably not from a financial standpoint, either."
The team set the high heating value of each of the four feedstocks tested as the basis for the study, instead of an equal weight measurement, and incorporated a sensitivity analysis to check findings. A cradle-to-gate boundary was applied and includes all product processes upstream of delivered dry biomass. Although algae's life-cycle analysis showed disappointing results, it has significant advantages in eutrophication potential and land use, the latter being invaluable. "We can figure out ways to deliver waste nutrients or what have you," Clarens explains. "Land we can't really improve on and algae are more efficient." In addition, algae yields four times as much biomass as the other crops.
Eutrophication impacts emerge upstream as runoff from the nutrient factory, Clarens says, leaving room for improvement there, also. "If we're talking about really expanding our agricultural efforts to be able to grow fuel, not just food, then doing it in a way that doesn't have the same impact on waterways I think is key," he says. Algae could also be cultivated using existing nutrients at power plants, confined animal feedlots and coal power plants. "Even if we took all the nutrients from all the people in the U.S., we wouldn't be able to grow enough algae to offset our energy needs," Clarens says. "So we're going to have to think of other ideas."
Clarens acknowledges that plenty of hype surrounds algae and it's not a silver bullet, but that doesn't negate its potential. "One of the things we were thinking early on is if it's as good as the claims floating around say, then we should quit our jobs and go do this because we could get really rich," he laughs, adding that it doesn't seem prudent without studies like this. "I'm optimistic and I think hopefully this paper will help start a conversation about where we should be focusing our efforts."
In response to the paper, Eckelberry says higher energy consumption by algae is not the fault of the organism, but the industrial process. "This study confirms our findings that a stand-alone algae production environment is not viable," he says. "You can't make algae in a vacuum."
The energy cost of oil extraction with big machinery is a nonstarter, according to Eckelberry. "You're trying to squeeze the water out of the Kool-Aid," he says, adding that OriginOil has developed an efficient process for extraction, as have other companies. As far as water use is concerned, Eckelberry believes the focus should not be on how much, but what kind. "I think we need to step back a little bit and say, ‘Algae is beneficial because it's going to take the wastewater and the salt water and the brackish water nobody can drink and it's going to remediate it.'"
Eckelberry argues that algae are not inherently higher GHG emitters than terrestrial crops, but emit a similar or smaller amount of pollutants when taking into account tractors harvesting up and down fields. "There's no question that algae aren't a virtuous cycle on greenhouse gases," he says. "It's the hope of the future."
The study showed that a good portion of existing data for algae cultivation is extremely obsolete, he says, and a new, reliable model is needed. "It's only a flag that says we didn't know much before."
A Productivity Model
Through a multiphase project with the U.S. DOE's Idaho National Laboratory, OriginOil has developed the Algae Productivity Model, which lays out a path for commercial production. It can be viewed at the company's Web site: www.originoil.com. Key variables of algae productivity identified include algae concentration at harvest, total volume available for algae growth, energy source, energy inputs, lipid content and lipid extraction efficiency. A partnership with London-based consulting firm StrategicFit will help further develop that core model. "Ours is just a bunch of spreadsheets and it works, but they can help turn it into modules," Eckelberry says.
Phase one of the Algae Productivity Model included a comprehensive mass-energy balance of OriginOil's proprietary production process, which includes the Helix Bioreactor and live or single-step extraction.
The model concludes that profitability requires co-location with beneficial site hosts and a focus on high-value coproducts. Subsequently, the pursuit of fuel will require continued process optimization at all stages and incentives such as grants, subsidies and policy. "The end game is to allow ventures to be financed based on reliable, bankable life-cycle analysis numbers," Eckelberry says.
Besides this venture, the DOE has lent a helping hand to several algae endeavors. In January, it announced the recipients of more than $80 million in competitive federal funding for biofuels research and development, of which $44 million went to the National Alliance for Advanced Biofuels and Bioproducts for the commercialization of algae production, according to the DOE. The American Recovery and Reinvestment Act granted funds to Sunrise Ridge Algae Inc. in Houston, Texas, for the first research and design phase of a project at Hornsby Bend Wastewater Sludge Treatment Facility in Austin, Texas. If awarded funding for more project phases-detailed design, construction and operation-Sunrise Ridge plans to operate its system at a cement company in Buda, Texas.
The DOE has had a long-term interest in algae because of its potential and productivity compared with land-based plants. The Aquatic Species Program was a precursor to the current Biomass Program within the DOE and studied algae for biodiesel.
The University of Nebraska-Lincoln will use $1.9 million in federal funding to help revamp a portion of its Beadle Center greenhouse to accommodate an algal biofuels research facility that will address three important goals: identify the best strains for maximum oil production; identify optimal growing conditions; and modify the algae for maximum cell density, according to Paul Black, a lipid biochemist at the university. The team is currently working with a photobioreactor that is designed to increase cell density per unit volume from about two grams per liter to eight to 10 grams per liter, by exploring maximum light and carbon dioxide conditions, Black said. Black expects that after about 10 months the scientists should have some compelling data, although a timeline has not been established.
Black and fellow scientists are working now with natural strains, but the possibility of genetic modification exists, depending on what genes are turned on or off by certain stimuli, such as light. "It depends on what we come across," he said. "There's a lot of serendipity in science."
An Unnecessary Risk
While many researchers are working to optimize algal traits through genetic modification (GMO), others express deep concerns with the practice, including destabilization of ecosystems, death of beneficial species of natural algae, creation of toxic GMO algae species that can directly harm people, irreparable alteration of the environment, and many more.
"Let's remember that algae are responsible for half of the oxygen on this Earth," says Gerald Groenewold, director of the Energy & Environmental Research Center on the campus of the University of North Dakota. "It's a fantastic group of species that are very important to life on Earth." Several thousand species of algae are thought to exist and humans understand little about them, he adds, including the extent of their interaction with the environment. "Therefore, changing that interaction through genetic modification creates a plethora of unknown consequences and probably some significant risks. We don't know where we're going with this. We're driving blind."
An environmental risk assessment protocol for GMO algae does not exist, which Groenewold considers a worrisome reality. "In simple terms, I think what we're doing is championing the creation of dangerous biohazards without having to address safety guidelines, because there is no guideline," he says.
The tremendous growth rate of algae makes genetic modification even more risky, as it would mean a "geometric spread" of any mistake, Groenewold explains. Furthermore, significant strides are being made in research with natural strains of the organism that are understood. "There is no necessity to pursue a far riskier GMO course of action when we're having significant success pursuing natural breeding," he argues. "This is a Frankensteinian exercise."
Genetic modification of algae needs to be critically discussed and evaluated to avoid a "biological nightmare," Groenewold says. "It's the most amazingly inappropriate thing, frankly, I have seen in years under the heading of science," he says of GMO algae. "It's very bad science in my opinion."
While technological barriers to large-scale commercialization of algae production for biofuels still exist, researchers are making advancements and the next step is to bring them together in a best-of-breed technology, Eckelberry says. "I have no doubt that the technologies are out there," he says. "They just need to be melded and put to work … There are process issues, of course, but there's no question it's got the potential."
Black cites cell density, quality oil and oil extraction as major barriers. "I would say it will be five to seven years before we really get to a point of making it commercially viable," he says. "We've got some blocks in front of us, but they're not insurmountable."
Lisa Gibson is a Biomass Magazine associate editor. Reach her at email@example.com or (701) 738-4952.