Could feeding cows seaweed drastically cut methane emissions?

ITV News Social Affairs Correspondent Stacey Foster delivers a special report on new efforts to tackle the planet's number one source of agricultural greenhouse gases


As world leaders prepare to meet for COP28 in Dubai – a special On Assignment asks whether scientific innovation can offer some hope in the fight against man-made climate change.   

I travelled to Sweden where a start-up claims they can reduce the methane emissions of cattle by up to 90% by simply adding seaweed to their diet. 

We started our trip on the Island of Gotland at Ejmunds Farm which has been in Märtha Norman’s family for six generations. It was the day after some of the cattle had gone to slaughter and so overnight, hundreds of new bulls had been transported into the cow shed where they will live for the next year before they’re large enough to sell for beef. 

It was at this farm, in the the summer, that 10 bulls took part in a trial to explore the effects of seaweed on methane emissions, breathed out by the livestock. The powdered seaweed, which has a strong smell and is granulated in form, is mixed into the normal feed of the cattle.

The seaweed was mixed into their food. Credit: On Assignment

The cows were fed the diet for three months before being slaughtered and sent to supermarkets packaged as “LOME” the brand name used for this new low-methane beef. 

When we went to the farm the trial was over but the results were astounding. The cows breathed out up to 90% less methane. 

Märtha Norman, Ejmunds Farm said: “We gave it to 10 bulls each day. It has a quite strong smell, but it doesn't taste anything really. And you would just sprinkle that in with the normal feed. It would be mixing for around 15 minutes maybe. And then you wouldn't see it when you mix it into the food."

Märtha talks to me about the challenges of farming because of climate change. Farmers here are always first to feel the effects with the unpredictable weather cycles that impact the food chain but they also feel an immense pressure to innovate to stay in business. 

Märtha is quite clear that feeding her entire herd with seaweed would add minimal extra work. It would be a case of mixing the powder with the grass and wonky vegetables they already prepare for the cattle.

But what she is concerned about is the cost of the seaweed and the extra paperwork involved in accrediting this climate-friendly product and getting it to market. 

I wanted to find out more about the process of producing the seaweed, so we went to Stockholm, to the Volta Greentech lab where the seaweed is being cultivated. There were several bottles of the algae at different stages of growth.

People were interested in the idea but questioned how much it would cost. Credit: On Assignment

Ioannis Dogaris, the lead researcher on this project, told me that they needed to upscale production in order to be able to feed the world’s cows, but the small scale trials have been successful. 

Mr Dogaris said: "We have managed to see up to 90% in some cases of reduction in, in methane from cows, beef cows for example. So that gives us a lot of potential to go forward in this process."

The “low methane” meat was prepared in a separate area of the Protos meat production facility. I met Ola Thomsson, the Purchasing Manager, who told me the success of low methane beef would hinge on consumer habits. 

She said: "In the end, it always comes down to who's going to pay for it. And, it has to be a huge impact on the market to get the consumers to actually also then pay for it. Because as it is now, it costs a little bit more to produce."

While on Gotland Island we visited a restaurant where the most popular item on the menu was beef steak.

Test results showed there had been a dramatic drop in methane. Credit: On Assignment

Unsurprisingly those we asked said they’d be interested in trying the more environmentally friendly alternative but were interested to know how much more expensive it would be and whether it would taste any different. 

Anna Sorby, a climate officer who advises the Swedish Government, spoke to us about the trial. She was sceptical about the size of the initial study. 

"I definitely see a potential there. And I think it could be expanded but it's also important to keep in mind that it's not gonna solve the climate crisis.

"It's just one small part of the puzzle. We have about 90% of the global emissions that we have to address in other ways.”

I was interested to hear that Anna believes it is far easier to change what the cows eat than to expect humans to change their own diets. 

The vets who reviewed the bulls after the trial said there were no known adverse effects on the animals that took part in the study after eating a seaweed diet for three months. 

The Swedish Government has invested a further one million euros to extend the trial and the Volta Greentech lab are expected to launch a trial using cattle in the UK in 2024, but the major setback, at the moment, is upscaling the production of the seaweed in order to fulfil the feeding requirements of animals across the world. 

Watch Stacey Foster On Assignment on Tue 28th November at 11:05pm on ITV1 or stream on ITVX


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