Meet the visionary businessman who believes he can turn seaweed into cash and tackle global warming in the process.

Sargasum, to me, it's almost kind of God's gift to climate change. There's so few things in nature that are as effective as sargassum, and yet so few people know about its wondrous properties.

He aims to set up what would be the biggest farm in the world,

using remote ocean currents to hold vast floating fields of seaweed in place.

The good thing about seaweed is that you can harvest it, like with the combine harvester.

They have enormous growth rates.

They double their biomass every 10 days.

The plan is to sell carbon credits, and the project backers believe their mega farm

will ultimately draw a billion tons of carbon dioxide from the atmosphere every year.

They say the venture will quite literally be floated in the

South Atlantic before the end of this decade. So will this audacious new approach to carbon capture work?

I'm Justin Rowlat and that's what we'll be exploring on Business Daily today.

The world's oceans already do some serious heavy lifting when it comes to pulling carbon dioxide out of the air. Sea water and the life forms that live within it suck up about a quarter of

the CO2 we put into the atmosphere annually. Land-based plants and forests account for another quarter.

Now a private company plans to earn carbon credits by giving nature a nudge, boosting the ocean's capacity to capture even more carbon

by cultivating vast fields of seaweed hundreds of miles from land. And it plans to do it on a truly

epic scale. My name's John Auckland and I'm a director at Seafields. Seafields is developing a hyperscale

seaweed farm that it's going to place in the South Atlantic to grow the brown seaweed sargassum

for the principal reason to sink it to the bottom of the ocean for carbon sequestration.

So when you say mega project, what do you mean?

So the eventual size of the farm is intended to be about 55,000 square kilometers.

55,000 square kilometers.

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