Can you build a seaweed factory for less than 100 million dollars?

About a year ago I wrote:

(...) it is reasonable to expect a considerable expansion of the world’s alginate supply in the next 5 years.

I stand by that. But such a throwaway sentence of course glosses over the struggle that is needed to bring a 21st-century bio-industrial vision to life.

While the authors of Alginor’s latest annual report try to make it sound as boring as possible, theirs has been a dramatic journey so far. The boat has been delivered on budget and the pilot plant is in full swing, but the demonstrator facility that is to process 33,000 tons of seaweed into 600 tons of food-grade alginate has fallen victim to major cost overruns.

Here’s an excerpt from the report (10 Norwegian Krone (NOK) is about 1 USD):

During 2024, Alginor raised NOK 430 million in equity, enabling significant progress on the F3 facility and providing a stronger financial foundation. As we moved deeper into project execution, we encountered significant cost increases in the F3 project due to a combination of overruns, unbudgeted expenses, and insufficient contingencies. (...)

To address this, the company successfully completed a private placement of NOK 100 million in March 2025 at NOK 10 per share towards Borregaard AS, Must Invest AS, and Jakob Hatteland Holding AS, who reaffirmed their long-term support for the company and its business case. (...)

In addition, Alginor will require external debt financing. Management is actively and diligently working to secure the necessary funding. The outcome is not yet assured, but we remain confident.

Thus far, just over 1 billion Norwegian krone ($100 million) has been invested into Alginor, but more debt financing is needed to finish the facility in Q1 or Q2 of 2026. To be clear, this is only the start of the project. Only the harvester and the F3 demonstrator facility extracting alginate will go into use at this time. The F5 facility that will use sidestreams and the F4 fully integrated biorefinery that will also make pharma-grade alginate are still some way off from being financed and built.

So was this a major management failure or is it simply the price of biorefining these days? An informal industry survey suggests it’s the former. Building a smallish alginate facility should not be that expensive.

The Alginor board seems to agree. The March 2025 round was a downround: shares were sold at NOK 10 compared to NOK 36 in previous rounds. Bad news for the unhappy shareholders, who wasted no time replacing the management team. The board and CEO Kjetil Rein “mutually resolved” that Rein would step down, while the company’s CFO Haakon Farstadvoll handed in his resignation due to his “ambition to pursue a career as a lawyer.”

Macro Oceans and Origin by Ocean unveil their plans for their own alginate factory

Did you see this announcement last month?

Finnish green chemicals company Origin by Ocean and the CABB Group, a leading contract development and manufacturing organization specializing in fine chemicals, have entered into a strategic partnership to establish a first-of-a-kind algae biorefinery at CABB's production site in Kokkola, Finland.

The facility (...) is set to begin operating in 2028, processing sargassum into high-value ingredients such as alginate, fucoidan, and biomass residue. Origin by Ocean will construct the biorefinery and CABB will operate it under a Manufacturing as Service (MaaS) arrangement. (...)

Origin by Ocean is currently looking for strategic investors and partners for the biorefinery.

And then this one, just a few days ago:

Macro Oceans (...) plans to build a zero-waste alginate plant in the US by 2027 - the first of its kind in decades. We’ll be able to provide food companies with something new - a secure, dependable domestic supply at commercial scale,” said Colin Hepburn, CTO of Macro Oceans.

Is this bio-innovation or are we simply reshoring? Start of a seaweed scaleup or just plans without funding?

What partnership model?

Biorefining requires partnerships, but there are different ways to go about that.

One option is a cascading model where each successive extraction is done by a different partner. Take for instance the Biowill project, where aspirin is first extracted from willow by a pharma company, which passes on the pulp to a plastics manufacturer to turn it into food packaging materials. The leftovers then go to another partner to generate biogas for energy, while the biogas digestate serves as an organic soil improver distributed via additional stakeholders.

Very complicated to have so many actors involved of course. Let’s hope no one goes bankrupt halfway through.. And how will the biomass move? Co-location in a central spot or are we shipping round the left-overs to each other’s factories?

Rummaging for answers through recent news on sidestream valorization, I struggled to draw a common thread. Are seaweed side streams like sugar beet pulp? In that case it’s just a matter of building your factory halfway between different sugar factories that are conveniently close to major industrial production sites - like AFYREN did in France.

Or is it more like corn stalks, in which case you’d have to completely invent your own harvesting system as well as organise a separate aggregation company co-owned by the corn farmers - all before you can build your processing facility, like New Energy Blue did in Iowa.

Or is it more like 5-HMF, in which case we just wait for a big company like Michelin to build an expensive chicken that will lay its own eggs? Perhaps it’s like the SUSTAINEXT project in Extremadura, where tobacco fields, no longer profitable as subsidies phase out, are being planted with botanical herbs and agrivoltaics to power a biorefinery that will yield 46 extracts out of which 13 are totally new in the market, for 6 industries: food, feed, nutraceuticals, cosmetics, chemicals and fertilizers.

I’ll stop here. But I could keep going. The message is clear: each distinct biomass comes with its own tailor-made value chain, business model and scale-up strategy.

This means that, when looking for success stories outside of the narrow algae scope, different regions will point to other directions.

New Energy Blue’s corn project mirrors what SOS Carbon has been pioneering in the Caribbean, while the tobacco farmers’ search for a new crop in Extremadura reminds me of the fishermen in Alaska and Maine. You could imagine an AFYREN-style facility in Qingdao where the scale is massive, while the Biowill model could be the near future for Europe, with its diversity of smaller extractors and application startups.

Just some observations, not sure if at all useful? Your comments are welcome.