Inside a futuristic farm in Iceland, seaweed is grown for food

In the shadow of Iceland’s largest geothermal power plant, a large warehouse houses a kind of high-tech indoor farm that’s like nothing you’ve ever seen.

Under a strange pink-purple glow, illuminated panels hum and cylindrical columns of water bubble, while a futuristic crop of microalgae grows.

It is here that Iceland’s Vaxa Technologies has developed a system that harnesses energy and other resources from the nearby power plant to grow these small aquatic organisms.

“It’s a new way of thinking about food production,” says CEO Kristinn Haflidason, as she shows me around the space-age facility.

For much of our history, humans have consumed algae, also known as macroalgae.

But its tiny relative, microalgae, has been a less common food source, although it was consumed for centuries in ancient Central America and Africa.

Now, scientists and entrepreneurs are increasingly exploring its potential as a sustainable, nutrient-dense food.

About 35 minutes from the capital Reykjavik, the Vaxa site produces the microalgae Nannochloropsis, both as food for people and for farming fish and shrimp.

A type of bacteria called Arthospira also grows, also known as blue-green algae, as it shares similar properties with microalgae.

When dried, it is known as spirulina and is used as a dietary supplement, food ingredient, and as a bright blue food coloring.

These small organisms perform photosynthesis, capturing light energy to absorb carbon dioxide and release oxygen.

“Algae eat CO2 or convert it into biomass,” explains Haflidason. “It’s carbon negative.”

The Vaxa plant has a unique situation.

It is the only place where algae cultivation is integrated with a geothermal power plant, which supplies clean electricity, cold water for cultivation, hot water for heating and even pipes for CO2 emissions.

“You end up with a slightly negative carbon footprint,” says Asger Munch Smidt-Jensen, a food technology consultant at the Danish Institute of Technology (DTI), co-author of a study assessing the environmental impact of Vaxa’s spirulina production.

“We also found a relatively low footprint, both in terms of land and water use.”

Renewable energy is needed 24 hours a day, plus a flow of CO2 and nutrients with a low carbon footprint, to ensure the facility is climate friendly, and he believes that cannot be easily replicated.

“There is a huge energy input to run these photobioreactors and you have to artificially simulate the sun, so a high-energy light source is needed,” he explains.

“My main conclusion is that we should use these areas (like Iceland) where we have low-impact energy sources to make energy-intensive products,” adds Munch Smidt-Jensen.

Back at the algae plant, I climb to a raised platform, where I’m surrounded by noisy modular units called photobioreactors, where thousands upon thousands of tiny red and blue LED lights power the microalgae growth, instead of sunlight.

They are also supplied with water and nutrients.

“More than 90% of photosynthesis occurs within very specific wavelengths of red and blue light,” explains Haflidason. “We only give them the light they use.”

All conditions are strictly controlled and optimized through machine learning, he adds.

About 7% of the crop is harvested daily and quickly replenished with new shoots.

Vaxa’s facility can produce up to 150 metric tons of algae annually and plans to expand.

As the crops are rich in protein, carbohydrates, omega-3s, fatty acids and vitamin B12, Haflidason believes that growing microalgae in this way could help address global food insecurity.

Many other companies are betting on the potential of microalgae: the market is estimated to be worth $25.4bn (£20.5bn) by 2033.

Danish startup Algiecel has been testing portable modules the size of shipping containers that house photobioreactors and could be connected to carbon-emitting industries to capture their CO2 while producing food and feed.

The crops are also used in cosmetics, pharmaceuticals, biofuels and plastic substitutes.

Perhaps microalgae could also be produced in space.

In a project funded by the European Space Agency, the Danish Technological Institution plans to test whether a microalgae can be grown on the International Space Station.

Despite all the investment, there is still some way to go before microalgae become an everyday part of our diet.

It still needs a lot of development, according to Munch Smidt-Jensen.

He points out that the texture lacks firmness. Meanwhile, the flavor may be “fishy” if the seaweed is from saltwater.

“But there are ways to overcome this,” he adds.

There is also the social issue.

“Are people ready for it? How do we get everyone to want to eat this?”

Malene Lihme Olsen, a food scientist at the University of Copenhagen who researches microalgae, says their nutritional value needs more research.

“Green microalgae (chlorella) have a very robust cell wall, so it can be difficult for us to digest and obtain all the nutrients,” he says.

For now, he says it’s best to add microalgae to other “carrier products” like pasta or bread to help with flavor, texture and appearance.

However, Ms Olsen believes that microalgae are a promising food for the future.

“If you compare one hectare of soybeans in Brazil and imagine that we have one hectare of seaweed field, you could produce 15 times more protein a year (from seaweed).”

Back at the plant, I see an unappetizing green sludge. These are the microalgae harvested with the squeezed water, ready for further processing.

Mr. Haflidason offers me a sample and, after my initial reluctance, I try a little and find its neutral flavor with a texture like that of tofu.

“We are not at all proposing that anyone eat green mud,” jokes Mr. Haflidason.

Instead, processed seaweed is an ingredient in everyday food, and in Reykjavik a bakery makes bread with spirulina and a gym uses it in smoothies.

“We are not going to change what you eat. We’re simply going to change the nutritional value of the foods you eat,” he says.