USC study shows promising potential for giant-kelp-based biofuel with depth-cycling approach
Scientists at the USC Wrigley Institute for Environmental Studies on Santa Catalina Island, working with private industry, report that a new aquaculture technique on the California coast significantly increases kelp growth, yielding four times more biomass than natural processes.
The researchers used a depth-cycling approach—i.e., physically moving the macroalgae between deep nutrient-rich water at night and shallow depths within the photic zone during the day to optimize growth. An open-access paper on their work appears in the journal
Renewable and Sustainable Energy Reviews.
This study tested the effects of depth-cycling on the growth, morphology, and chemical composition of the giant kelp Macrocystis pyrifera, a target species for renewable biomass production. Giant kelp grown under depth-cycling conditions had an average growth rate of 5% per day and produced four times more biomass (wet weight) than individuals grown in a kelp bed without depth-cycling.