Algae: A Sustainable Resource for Growing Protein

17 Feb, 2012

Protein is directly tied to resource intensity. Vegetarians choose a meatless path to cut down on the vast quantities of land, water, nitrogen, and pesticides required to produce most livestock feed. And many meat eaters are thinking strategically about the greenest sources of animal protein. But what if animals didn’t require pound upon pound of industrially grown corn or soybeans to grow?

One solution might be algae. That’s right—pond scum has promising potential as a source of animal feed, as well as human feed and fuel.

“Algae is really the premiere sustainable source of raw materials for food and feed,” said Jim Astwood, vice president of product management for Aurora Algae, a company that’s been cultivating the plant in the desert of western Australia to explore its commercial possibilities. “The water and land footprint is small compared to traditional agriculture and there’s high productivity.”

Algae can be cultivated in human-made ponds on otherwise unusable desert land, requiring only sunlight and seawater to grow. It’s about 30 times more productive than soy (and 50 times more productive than corn), but requires only 1 percent as much fresh water. It also has a much higher protein content—up to 70 percent, compared with about 10 percent in corn and 40 percent in soy.

Replacing at least some corn- and soybean-based livestock feed with algae-derived feed would not only shrink the life-cycle impact of meat, it could free up a lot of land currently devoted to the production of animal feed, making more of it available for crops that directly feed humans instead.

“If we could use this biomass to replace soybeans [in animal feed], then we could have a lot of soybeans for human consumption,” explained Xingen Lei, a Cornell professor who’s been testing algae as an animal feed supplement. (Not that soy doesn’t have its own problems as a protein source.)

The same solution could be applied to aquaculture, an industry growing rapidly with the depletion of natural fisheries. The Organization for Economic Cooperation and Development expects that by 2015, aquaculture will surpass capture fisheries as the primary source of fish for human consumption, and that the industry will be affected by “rising commodity prices in general and the impact on producers, e.g. soybean prices influencing the price of fish feed and the price of farmed fish.” Algae’s extremely low impact compared to soy and corn could make it an ideal sustainable ingredient in fish feed, and could help keep farmed seafood prices from skyrocketing in response to volatile crop markets.