Polytechnic prof Milton Sommerfeld exploring the possibilities of algae as super food, fuel, fertilizer and more
Milton Sommerfeld can see the future in puddles.
One of the nation’s top experts on algae, Sommerfeld has spent almost 50 years cracking dozens of uses for the plant. In Sommerfeld’s future, you will fill your tank with it; feed it to livestock; fertilize crops, lawns or flowers; clean up wastewater with it; and eat it.
One of the best strains he ever found was in a puddle after a storm in Phoenix.
“We picked it up and it started growing, and it produced over 50 percent of its weight as oil,” Sommerfeld said. “You never know where you’re going to find an algae strain that has value for a different type of product.”
There are about 75,000 different types of algae, ranging from microscopic specimens to kelp a hundred feet long and as big around as a baseball bat. It can look like lime Kool-Aid, black or brown crude oil, or hearty burgundy.
“It’s a very broad-spectrum use,” said Sommerfeld, professorSommerfeld is a professor in the Environmental and Resource Management Program in the Polytechnic School, which is part of the Ira A. Fulton Schools of Engineering. Sommerfeld is also a senior sustainability scientist in the Julie Ann Wrigley Global Institute of Sustainability. in the Polytechnic School and co-director of the Arizona Center for Algae Technology and Innovation.
“The focus has been on biofuels,” he said. “It’s believed that the petroleum we take out of the ground had its origin in algae millions of years ago. If you look at the chemistry of algae oil, the lipids, it pretty much matches petroleum. Anything you can use petroleum for, you can pretty much use algae oil. That means not only fuel in terms of diesel, gasoline and jet fuel — you also have the specialty products that can be made, like plastics and so on.”
Algae has some surprises in its membranes, like Omega-3 fatty acids, which are believed to help cardiovascular health, among other benefits. Omega-3 is usually referred to as a fish oil. It’s actually an algae oil. Algae oils will eventually replace Omega-3 supplements found in health-food stores.
“The fish have simply accumulated them by eating little animals that ate algae,” Sommerfeld said. “We always say, ‘Let’s cut out the middle fish and go right to the algae for those specialty products.’ ... We just haven’t used the algae to its fullest extent. More and more people are looking at the algae as the source for some of these specialty products that actually now comes from a plant source.”
Sommerfeld grew up on a farm in Texas. His father made him clean the algae out of the cattle trough. Every week, he cleaned it out. Every week, it came back.
“I kept wondering why it grew so fast,” he said. “That was how I first related to the algae.”
One of the major focus areas of Sommerfeld’s lab is how to relate algae to the water-energy-feed nexus. Algae can be grown in dairy wastewater or in sludge from water treatment plants, stuff that’s usually trucked to landfills. Grow algae in that, take out the oil, and you’re left with a nitrogen-rich biomass perfect for fertilizer.
“It’s high-protein,” Sommerfeld said. “Now you have a high-protein source for animal feed, or even potentially human food.”
The biggest immediate impact from algae will be bioremediation — cleaning up environmental threats — and producing specialty chemicals, according to Sommerfeld. Why not fuel, if it’s so readily extracted? Sommerfeld has cooked up biodiesel in his lab from algae. Why hasn’t ExxonMobil built giant ponds?
The problem is taking algae farming to a large scale. Most work with algae has been at small scale, although some people have tried unsuccessfully. There are huge challenges in introducing a new crop to industrialized agriculture.
“Just think about trying to introduce a new crop at large scale,” Sommerfeld said. “We don’t do that now.
“If you look at our crop plants, they started on small farms and got bigger and we learned how to do it and got bigger machinery and bigger this and bigger that, all kinds of improvements in seed because through a different process because there was a big market for food or whatever you get out of the grain.
“Now you’re trying to do this with a product that’s a commodity product: oil. It’s a commodity product. It’s cheap. Now you’re trying to compete with an industry that’s been here more than 100 years.”
On a four-acre site directly across the street from Sommerfeld’s lab on ASU’s Polytechnic campus in Mesa, he is working on bringing algae cultivation to a production scale. In the baking sun sit racks of panels with algae bubbling in them and long test beds lined with white plastic where mill paddles churn scarab-green and wine-dark water. Four years ago the U.S. Department of Energy invested $15 million to find out how to grow algae outdoors in a production setting.
There’s a lot more to it than simply transferring what you did inside in a test tube to a 300,000-liter test bed outside. Sometimes that works, Sommerfeld said. Sometimes it doesn’t.
“One of the things that happens we’re finding when we started to begin to scale up and do it outdoors, it’s that there are a lot of little animals that get in,” he said. “We have the same kinds of problems that farmers have with insects.
“Now you have these creatures that blow in with the wind and the dust storms, and they love to eat the algae. They cause what we call algal crash. All of a sudden the cells begin to come together and turn brown and settle down. It’s sort of like they’re dead, and you have to almost restart the system, which is very expensive on a large scale. One of the things we’ve been doing recently is really trying to detect and identify those organisms and look at how do we control them like insects. We’re having a little success in doing that.”