Giant kelp farms could feed the world.
Bren Smith has pioneered what he calls ‘3D ocean farming’ (or vertical kelp farming) to feed the world. *
- Kelp can be eaten in various ice-creams, salads, and dried or fried snacks.
- The base of the kelp farm can grow all the shellfish and oysters we could want.
- Kelp farms encourage other fish and ocean creatures to grow, stimulating the ocean ecosystem and creating a larger fish catch.
- It soaks up nutrient pollution that causes dead zones, and returns some of those NPK nutrients back to our land or soils if we harvest the kelp for fertiliser!
- About 2% of the world’s oceans have enough nutrients to grow kelp, but the actual area required to actually feed the world is far less. The oceans are 361.9 million km2, and 2% of that is 7.2 MILLION km2). But the area required to feed the world is only about 180,00 km! (See quote below). That means the nutrient rich 2% of the world’s oceans are 40 times larger than we need to feed today’s population!
- “Seaweed farms alone have the capacity to grow massive amounts of nutrient-rich food. Professor Ronald Osinga at Wageningen University in the Netherlands has calculated that a global network of “sea-vegetable” farms totaling 180,000 square kilometers — roughly the size of Washington state — could provide enough protein for the entire world population. The goal, according to chef Dan Barber — named one of the world’s most influential people by Time and a hero of the organic food movement — is to create a world where “farms restore instead of deplete” and allow “every community to feed itself.”But here is the real kicker: Because they require no fresh water, no deforestation, and no fertilizer — all significant downsides to land-based farming — these ocean farms promise to be more sustainable than even the most environmentally-sensitive traditional farms.” http://www.theatlantic.com/international/archive/2011/11/the-coming-green-wave-ocean-farming-to-fight-climate-change/248750/
- Bren Smith’s TED talk is on youtube
- He’s so serious about his vision for feeding the world that he has open-sourced his farming system. http://greenwave.org/
- Kelp could also act as a biomass feedstock for the vat-grown meats that are starting to come down in price and will soon be competitive with normal meat from animals. http://www.nextbigfuture.com/2017/02/lab-grown-meat-prices-have-dropped.html
- IF that worked, it means we could stop farming all our meat livestock and return a third of the (non-ice) land on earth to nature, getting all our protein from kelp from the sea & vat-grown meat!
- Kelp could also be biocharred to help improve soil quality, which would reduce the water and nutrients required to grow our crops. The bottom line? Could kelp be the silver bullet that will fertilise all our agricultural needs and replace all our grazing needs? Could kelp give us all the seafood and wheat and rice and lamb and chicken and beef and turkey that the world could ever want, without killing any animals and returning all that grazing land back to nature? (Which is a third of the non-ice surface of the earth!)
- Could kelp be the silver bullet to feed the world?
It gets more fantastic than ‘just’ feeding the world!
- Tim Flannery (Australian of the year and member of the Australian Climate Council) discusses a paper about super-giant kelp farms that cover 9% of the world’s oceans. But as we have seen, the problem is only 2% of the world’s oceans have enough nutrients (from erosion or oceanic upwelling) to grow kelp. Where do the extra nutrients come from for a patch of ocean the size of the African continent? In-situ recycling, they claim. First they farm the nutrient rich waters. Then a previous season’s kelp is biodigested in big submersible bags to collect methane gas out the top, leaving the digested kelp nutrients behind. These are then recycled into slow drip feed hoses and ‘tea-bags’ that slowly fertilise the kelp in what would otherwise be nutrient poor water. They claim we can recycle nutrients and grow kelp out in the open ocean, away from the continents or ocean upwelling areas. But I find it hard to believe that nutrients can be recycled in situ like this without the ocean just washing it away too quickly to be absorbed? That seems to be the crux of the matter, and I have no way of testing the claim.
- IF it works, the results could be amazing!:-
- half a kilogram of seafood per person per day, to feed a world of 10 billion people!
- all the biofuels and biogas we could need to replace fossil fuels and provide the ultimate backup to wind and solar power
- remove ocean acidity
- restore our atmosphere to 350ppm by 2085
- In other words, is seaweed farming a silver bullet to feed the world, save the oceans, and save us from climate change?
- It’s all in this free PDF. “Negative carbon via Ocean Afforestation”. Just register, and download it for free. http://www.psep.ichemejournals.com/article/S0957-5820(12)00120-6/abstract
- I still think we’ll need abundant reliable electricity from nuclear power, as the in-situ nutrient recycling above sounds dubious. But even if we could only farm Bren Smith’s way and at least feed the world from the oceans, let alone going to the full Tim Flannery 9%, would not that be an amazing break for the environment?