Agriculture has a long history as a vibrant, vital part of local economies, but improvements in farming technology, while increasing productivity, have often had a detrimental impact on the environment. From the Dust Bowl to pollution caused by chemical fertilizer, we’ve learned that maintaining an ecological balance is more challenging than it appears.
One major impact comes from industrial farms, which, by nature, generate large, concentrated amounts of waste in the form of manure from livestock and nitrogen runoff from fertilizer that pollutes waterways. Scientists have dreamed of turning that waste into something beneficial. But while it’s long been possible to produce fertilizer from manure and fuel from agricultural waste, the products aren’t priced high enough to justify the investment in building processing facilities and to pay for transporting the waste to the facilities and then distributing the finished products.
Now, promising research at Washington State University aims to harness agricultural waste as a food source for algae, which can then be used to produce not only biofuel but also products that may be marketable as food supplements. Shulin Chen, head of the Bioprocessing and Bioproducts Engineering Laboratory at WSU, is a leader in the field. “Most other people are working on one aspect of the car,” says John Gardner, dean of the Bainbridge Graduate Institute and a former vice president at WSU. “He is working on the whole system.”
Algae are one of Chen’s main projects. The low-impact organisms have a high lipid content, making them prime candidates for biofuel production. Biofuels made from algae are “drop-in” fuels, nearly identical in structure to petroleum-based fuel, which means they can utilize the same pipelines and pathways. Algae also have high yields, can grow on otherwise infertile substrates and thrive on a diet of organic waste. Engineers at the Department of Energy’s Pacific Northwest National Laboratory have even created a continuous chemical process that produces useful crude oil minutes after they pour in harvested algae.
If Chen were planning solely to make biofuel, his ideas might not seem very promising. It’s tough to compete with cheap oil. But algae can be processed to produce far more than lipids for biofuel. The proteins, polysaccharides and pigments that make up the remainder of the algal structure have other uses, Chen explains. Some of the co-products present in algae, he says, can tap into the high-value global nutraceutical product market. Nutraceutical, a combination of nutritional and pharmaceutical, refers to food that can have benefits to human health beyond their nutritional value. They include products like food supplements, which can sell for as much as $100 a pound, and whose total sales are expected to reach $204.8 billion by 2017. Dairy products, cereal and infant formula often contain such supplements.
Chen’s lab can tailor the algae’s food supply and their processing techniques to their ideal products. Different algae strains produce different co-products, and deciding which algae to grow and what to feed them is an intricate equation. “We design the process to optimize the match between the two,” Chen says.
The idea of using co-products to boost the value of biofuel production isn’t a new one, Gardner says. Many co-products of the petroleum industry, such as lubricants, additives and solvents, are worth more than the oil itself. The market for glycerin, a co-product of ethanol, is established and growing, and CO2, another co-product, is sold for beverage carbonation, dry ice, fire extinguishers and a variety of other applications. But ethanol is a first-generation biofuel and the industry is no longer in its infancy. Algal biofuels and other second- and third-generation fuels, despite their many advantages, are less established, and the leap from small-scale success to big-market item is a tricky one.
If anyone can make that leap, Chen can. He has published more than 210 journal papers, co-authored 30 patent applications in the field of biological systems engineering and logged more than a decade at WSU. His optimism is contagious. “We have the resources,” he notes. “We just need people to work together and make it happen.” He’s working with a cadre of experts. WSU is a leader in biofuel research and helped found the Sustainable Aviation Fuels Northwest project, a 2010 collaboration with Boeing, Alaska Airlines and more than 40 airports around the Pacific Northwest.
Nutraceuticals are made up of molecules that provide health benefits, and are often isolated from food and made into supplements. One common example are omega-3 and omega-6 fatty acids, which are usually derived from cold-water fish and flaxseed, then sold as oil capsules. Other nutraceutical products include dietary fiber, probiotics and alkaloids. The market is projected to grow by 6.3 percent a year through 2017. Chen speculates that people are willing to pay high prices for supplements because they understand the value of preventive care. For many, pills may also be more convenient than trying to track vitamin levels in their diets.
One nutraceutical Chen has recently focused on is lutein. The antioxidant occurs in high levels in some fruits and vegetables, including spinach, orange peppers and squash. A relative of beta carotene, lutein occurs in the human eye, where it functions as a protective pigment that minimizes sun damage. Lutein supplements are marketed as protection against macular degeneration, cataracts and other degenerative eye ailments, and carotenoids like lutein are often used as colorants in food products. A 2011 paper stated that sales of lutein in the United States alone were around $150 million.
Marigold petals are the main source of lutein, but processing is labor intensive and requires a lot of land. Chlorella sorokiniana, a green algae, is considered to be a promising alternative. The trick is optimizing both production of lutein and lipid yield in the algae. Light, temperature and nutrient concentrations can all affect algal growth, and Chen’s work involves juggling those factors with cost and ease of production.
The food processing industry is a significant chunk of Washington’s economy. A 2011 fact sheet from the WSU IMPACT Center reported a $9.5 billion value for agricultural production in the state, and food processing and manufacturing was worth $1.5 billion in value added. “I can see a synergy between the food processing and biofuel industries,” Chen says. “Wastes are major renewable resources. There’s no reason we can’t convert all [organic] waste into high-value products. Our goal is to recycle and reuse 100 percent.” Chen has been experimenting with growing high-lipid algae on cull potatoes, those that are too small to sell. Washington state ranks second in the country in potato production, making potato waste a reliable feed source for Chen’s algae.
Lack of technology was an obstacle to this sort of production in the past, Chen observes, but his lab has proven that harvesting biofuels and nutraceuticals simultaneously is possible. He’s now reaching out to potential commercial partners. He and Gardner believe this type of production could remove some of the burden of agricultural waste and make algal biofuels financially viable. Others seem to agree that algae is on the way up, including the Department of Energy, which invested $22 million in algal biofuel projects last year. The goal is to support development of cost-competitive algae biofuels by 2022. The cost of petroleum is currently about $100 for a barrel of crude, while estimates for algal biofuels range widely, generally falling between $200 and $400 per barrel. Cost varies depending on how and where the algae are grown. In colder climates, they require indoor facilities, and estimates are higher for algae grown using light rather than organic carbon as a food source.
Chen has been interested in co-products since taking his position at WSU, and his diligent work has proven that nutraceuticals could be a boon for the algal biofuel industry. He gets more excited about the potential every time he talks to someone about his projects. “To me,” he says, “it’s just a matter of time.”