Could a new biofuel source be found off the Catalina coast?

With three quarters of the planet covered in water, kelp might be part of the solution to finding a new biofuel. That theory is being tested off the coast of Catalina Island.

Video Transcript

- Could the fuel for a clean energy revolution be found underwater off the coast of Catalina? Our Phillip Palmer with the undersea solution that could be fueling our future.

PHILLIP PALMER: Something amazing is happening off the coast of Catalina Island at the USC Rigley Institute for Environmental Studies. The US needs billions of tons of biomass every year for biofuel. Corn, soybeans, and other land crops are most common, but come with indirect negative environmental impacts, along with the economic and moral consequences of choosing between food or fuel. With 3/4 of the Earth's surface covered in water, kelp might be part of the solution.

DIANE KIM: You know, I think we just made a major breakthrough. I think kelp as a biofuel source has been investigated for a while. But how to grow it on a scale that is commercially relevant has been the missing piece.

PHILLIP PALMER: Beginning in 2019, Marine Bioenergy and USC researchers began testing a concept to farm kelp in the open ocean. Kelp is one of nature's fastest-growing plants and is considered perfect for making bioethanol. But it naturally grows in water bathed in sunlight up to about 60 feet. In the open ocean, water near the surface is nutrient-poor, but loaded with nutrients in deeper waters. Trying to take advantage of both was the inspiration for what's being called a kelp elevator.

BRIAN WILCOX: We can protect the kelp. We can protect all the hardware. And since we have to go down to the nutrients every night anyway, this is easy to do.

PHILLIP PALMER: A test buoy and a winch were placed off the coast of Catalina Island. USC biologists attached kelp to an underwater boom, then for 104 days surfaced the kelp during the day to absorb sunlight, and at night, dragged the kelp over 260 feet deep into nutrient-rich waters. In a study published February 19, the researchers found that kelp not only survived the lower depths and the return to the surface, it grew four times faster than kelp grown naturally.

DIANE KIM: I screamed in joy a little inside.

IGNACIO NAVARRETE: Yeah. Some people were sure it would work. Some people were sure it wouldn't work. I was more on the fence, where I just had no idea what would happen. And so when we started to get the first pictures of the kelp growing on there, it was just-- yeah, this is amazing. Like, it's really growing.

PHILLIP PALMER: A plan is in development to build a pilot-scale ocean farm, which would be depth cycled using solar-powered drone submarines and then harvested four times a year without requiring land, fresh water, artificial fertilizers, or pesticides. Millions of tons of biomass to replace liquid fossil fuel could be created at competitive prices.

CINDY WILCOX: Our farms are going to be really close to the coast. But to the degree that all the nutrients float all over the ocean, we help absorb some of those nutrients, that's beneficial, because sometimes, it's just too many artificial nutrients dumped into the ocean through runoff from agriculture and so on.