For years, the biofuels we use to power cars, ships, jet airplanes, and big trucks have come mainly from corn and other mass-produced crops from farms — but researchers recently discovered it might also be possible to grow kelp crops for low-carbon biofuel, according to a new study published in the journal Renewable and Sustainable Energy Reviews.
The world of tomorrow might be powered by seaweed
The new study describes how a new aquaculture technique on the California coast substantially increases kelp growth, creating four times more biomass than natural processes. This novel technique uses a contraption called the "kelp elevator" capable of optimizing growth for floating algae — which it does via raising and lowering it to varying depths.
Scientists at the USC Wrigley Institute for Environmental Studies on Santa Catalina Island worked with private industry to produce the new report. The study suggests it could be possible to grow kelp crops in the open ocean to procure low-carbon biofuel, not unlike how land is used to harvest fuel feedstocks — which can include sugarcane and corn — but with the potential for fewer environmental impacts.
Kelp can 'maximize growth' on the California coast
The National Research Council has suggested the production of biofuels from feedstocks like soybeans and corn can increase water pollution. Additionally, when farmers use fertilizers and pesticides on crops, they can ultimately pollute streams, lakes, and rivers. Despite mountains of evidence on these drawbacks, 7% of the country's transportation fuel is still sourced from major food crops — nearly all of which is corn-based ethanol.
"Forging new pathways to make biofuel requires proving that new methods and feedstocks work," said Diane Young Kim, a corresponding author of the study and associate director of special projects at the USC Wrigley Institute — who is also a professor of environmental studies at USC Dornsife College of Letters, Arts, and Sciences.
"This experiment on the Southern California coast is an important step because it demonstrates kelp can be managed to maximize growth," added Kim.
Challenges to bringing kelp to sustainable fruition
Industries and governments both see promise in a new generation of eco-friendly biofuels capable of reducing net carbon dioxide emissions — in addition to lessening the country's reliance on foreign oil. Novel biofuel sources might either supplement or replace gasoline, jet fuel, diesel, and natural gas.
If kelp can fulfill this potential, it could become more attractive than conventional biofuel crops — including switchgrass, canola, soybeans, and corn — for two crucial reasons: Ocean crops don't need to compete for agricultural land, freshwater, or artificial fertilizers. Second, fragile habitats aren't threatened by ocean farming — since only a marginal area (or volume) of water is used for cultivation.
California and the federal government have both prioritized the generation of biofuels for years. The US. Department of Energy's Advanced Research Projects Agency-Energy has already invested $22 million in projects designed to increase marine feedstocks for the procurement of biofuels — including $2 million dedicated to the kelp elevator study. As more industries begin to adapt to sustainable energy alternatives, underrated ones like kelp may gain traction like never before.