Introducing this century’s potato: seaweed served from the bed of the ocean

Danish waters are well-equipped to take advantage of a lucrative farming opportunity, but it must be done with respect for the marine environment.

Denmark and the Netherlands are among the most intensively farmed… countries in Europe, but space is running out. The need to expand into new areas, along with the sustainability trend, has inspired the Danish business, agriculture and research industries to farm the Danish seabed. 

A cash crop

In 2010, 19 million tonnes of seaweed were produced globally. Some 95.5 percent of it originated from Asia and had an estimated market value of 31.5 billion kroner, according to an FAO report from 2012. 

Researchers at the algae centre at Havets Hus in Jutland are working to show the potential of farming macroalgae (seaweed). One of the researchers, Annette Bruhn, sees great potential in the industry.

“We hope to document that there are prospects in farming seaweed in Denmark,” she noted in her research. 

“The produced seaweed has numerous purposes and can remove nutrients from the marine environment. If we can document this, seaweed can be farmed in many areas in Denmark, and this has the potential to become a huge industry.”

Seaweed can be used for bio-energy, its cultivation is simple, there’s no need for fertiliser, it sucks up CO2, and its market value is high. Current projects, part of several international research initiatives, include cultivating it in tanks and along buoy-fastened ropes in the sea – pilot experiments that will clarify what work still needs to be done. 

Easy on the environment

“Many will argue that the farming of seaweed will lead to an exploitation of Danish waters, similar to the exploitation of Danish land for farming,” Henning Mørk Jørgensen from the Danish Nature Foundation (DN) told the Copenhagen Post.

The difference here however, he continued to explain, is that, while terrestrial farming requires a lot of input, research thus far shows that farming seaweed requires almost none. In fact, they help remove much of the unwanted outputs from terrestrial activities. 

With 7,000 kilometres of coastline and over 500 species of algae already growing in Danish waters, along with the ease with which it is farmed, many Danes see great potential in ocean farming. 

Keep the public onside 

However, the coastline is also in high demand from other activities: fishing, tourism and sand-extraction, just to mention a few.

The latter of these recently caused a problem, which could increase public scepticism towards other seabed activities like seaweed farming.

The coastal authorities, Kystdirektoratet, permitted sand extraction from the Øresund this spring without looking into the consequences.  And as a result, many of the beaches along northern Zealand have suffered as tidal patterns have been disrupted. 

“Permits were given from the desk,” a senior civil engineer and coast technician, Holger Toxvig, told Lokalavisen Frederikssund.

Deep waters necessary

The environmental impact of seabed farming certainly needs more consideration, according to Jørgensen.

 “The algae needs to be farmed in deep and open areas, where there’s plenty of space and where it won’t have an effect on sunlight penetration,” contended Jørgensen.

Research has thus far shown that farming along the coast isn’t viable.

“Eel grass and submerged aquatic vegetation relies on shallow depths for light – if we farm the algae here, we risk endangering the survival of these species.”

Seaweed’s on the menu

Research shows that farming the ocean seems to be the next sensible step – we’ve simply run out of space on land. 

Although seaweed may be an unappealing diet for some, it is healthy, sustainable, carbon positive and has great market value. 

Wakame for all?


  • Asia produces 95.5 percent pf the global seaweed at a market value of 31.5 billion Danish kroner
  • Danish researsh is looking into using locally-farmed seaweed for organic animal fodder, gourmet food products, organic fertiliser and sustainable bio-energy
  • Seaweed removes nutrients from the marine enviroment and could give Denmark clearer waters
  • About 1,000 tonnes of mussels are farmed in Denmark each year- they also help remove nutrients from the marine enviroment and provide animal fodder
  • Harvesting seaweed and mussels can help Denmark meet the goals of the EU Marine Directive


Photo caption: (Photo: Colourbox) What’s not to like about seaweed?

Nanna G Vansteelant, CPH Post

View original article at: Introducing this century’s potato: seaweed served from the bed of the ocean

Leave a Reply