MacroFuels · Project

Turning Seaweed into Transport Fuel Without Using Farmland or Fresh Water

energyPrototypeTRL 5

Imagine growing fuel in the ocean instead of on farmland. This project figured out how to farm seaweed at scale — rotating between brown, red, and green varieties like a farmer rotates crops — and then convert it into fuels like ethanol, butanol, and biogas. The big deal is that seaweed doesn't need fresh water, fertile land, or fertilizers, so it doesn't compete with food production. The team took the technology from lab-scale chemistry up to kilogram-scale production, targeting heavy transport and potentially aviation fuel.

By the numbers

25 kg/m²/year

Target seaweed biomass yield (wet weight)

1000 m²/hr

Seaweed harvesting rate target

90%

Fermentation efficiency for ethanol and butanol

90%

Carbon conversion rate for biogas from residues

15 g/l

Bio-butanol yield target

>4%/l

Bio-ethanol concentration target

10-30%

Fermentable sugar concentration from pre-treatment

13 partners, 6 countries

Consortium size and geographic spread

TRL 3 → 4/5

Technology readiness advancement

The business problem

What needed solving

Heavy transport and aviation remain heavily dependent on fossil fuels, and conventional biofuels compete with food production for farmland and fresh water. Companies in these sectors face mounting regulatory pressure to adopt renewable fuels but lack scalable alternatives that don't create new environmental trade-offs. Seaweed-based biofuels could fill this gap — but the conversion technology has been stuck at lab scale.

The solution

What was built

The project developed a complete seaweed-to-biofuel chain: a rotating crop cultivation system for year-round harvesting, pre-treatment methods yielding 10-30% fermentable sugars, fermentation processes producing ethanol and butanol at 90% efficiency, biogas production converting 90% of residue carbon, and thermochemical conversion scaled from milligram to kilogram quantities. Policy briefs and a knowledge repository were also delivered.

Audience

Who needs this

Biofuel producers seeking non-food feedstock alternativesHeavy transport fleet operators under decarbonization mandatesShipping companies needing marine-compatible renewable fuelsSeaweed farming operators looking for higher-value biomass marketsAviation fuel suppliers exploring sustainable aviation fuel (SAF) pathways

Business applications

Who can put this to work

Marine Biofuel Production

enterprise

Target: Biofuel producers or petroleum refiners looking for non-food feedstock alternatives

If you are a biofuel company struggling with feedstock costs and land-use competition — this project developed a rotating seaweed crop system yielding 25 kg wet weight per m2 per year, harvested at 1000 m2/hr. The process converts seaweed sugars into ethanol (>4%/l concentration) and butanol (15 g/l yield) at 90% fermentation efficiency, giving you a scalable marine biomass pathway that sidesteps agricultural land entirely.

Heavy Transport & Shipping

enterprise

Target: Fleet operators and shipping companies under pressure to decarbonize

If you are a heavy transport or shipping operator facing tightening emissions regulations — this project developed seaweed-based liquid fuels (ethanol, butanol, furanics) specifically designed for heavy transport and potentially aviation. The feedstock requires no fresh water or arable land, and offers high CO2 reduction potential compared to fossil fuels. The biogas pathway converts 90% of available carbon in processing residues, minimizing waste.

Aquaculture & Seaweed Farming

mid-size

Target: Aquaculture companies or coastal operators looking to diversify into energy crops

If you are an aquaculture operator looking for higher-value uses for seaweed biomass — this project developed advanced textile substrates and a rotating crop scheme using native European seaweed species for year-round harvesting. The target yield of 25 kg wet weight per m2 per year at a harvesting rate of 1000 m2/hr makes large-scale seaweed farming economically viable for the biofuel supply chain.

Frequently asked

Quick answers

What would seaweed-based biofuel cost compared to conventional biofuels?

The project performed an integral techno-economic assessment of the entire seaweed-to-biofuel chain, but specific per-liter cost figures are not publicly available in the project data. The economic viability targets included ethanol concentrations above 4%/l and butanol yields of 15 g/l — thresholds identified as economically relevant. Contact the coordinator for detailed cost projections.

Can this scale to industrial volumes?

The project advanced thermochemical conversion from milligram scale to kilogram scale, and the cultivation system targets 25 kg wet seaweed per m2 per year at 1000 m2/hr harvesting rates. However, the technology reached TRL 4/5 (lab validation to relevant environment), meaning further scale-up investment is needed before commercial-scale production.

What about intellectual property and licensing?

The project generated knowledge and data across algae cultivation, treatment, storage, and fuel production. Based on available project data, some results are covered by IPR protections and were excluded from the public repository. Licensing arrangements would need to be discussed directly with the consortium partners.

Which types of fuel can actually be produced?

Four fuel types were developed: bio-ethanol, bio-butanol, furanics (liquid fuel precursors), and biogas. These target the heavy transport sector and potentially aviation. The fermentation processes achieved 90% sugar-to-fuel conversion efficiency for ethanol and butanol.

Does this technology meet EU renewable fuel regulations?

The project produced policy briefs and strategy papers with recommendations for EU and national policy makers. Seaweed-based fuels qualify as advanced biofuels under EU directives since they don't use food crops or arable land. The project also addressed standards, norms, certifications, and regulations relevant to seaweed biofuels.

How far is this from commercial deployment?

The technology was taken from TRL 3 to TRL 4/5 during the project (2016-2019). This means it has been validated in a relevant environment but still requires pilot-scale demonstration (TRL 6-7) and pre-commercial scale-up before market deployment. Several years of further development and investment would be needed.

What happens to the leftover seaweed after fuel extraction?

Processing residues are converted into biogas, with the project achieving 90% conversion of available carbon in the residues. Additionally, proteins are extracted as a co-product. This cascading use of the full biomass improves the overall economics of the process.

Consortium

Who built it

The MacroFuels consortium brings together 13 partners from 6 countries (Austria, Belgium, Denmark, Iceland, Netherlands, UK), with a strong 54% industry ratio — 7 industrial partners including 3 SMEs alongside 5 research organizations and 1 university. This industry-heavy composition signals genuine commercial interest in seaweed biofuels. The coordinator, Teknologisk Institut (Denmark), is a well-established applied research organization with strong ties to industry. The geographic spread covers key North Atlantic and North Sea coastal nations with existing aquaculture and maritime infrastructure, which is strategically relevant for seaweed cultivation scale-up.

TEKNOLOGISK INSTITUTCoordinator · DK
AARHUS UNIVERSITETparticipant · DK
SIOEN INDUSTRIES NVparticipant · BE
THE SCOTTISH ASSOCIATION FOR MARINE SCIENCE LBGparticipant · UK
NEDERLANDSE ORGANISATIE VOOR TOEGEPAST NATUURWETENSCHAPPELIJK ONDERZOEK TNOparticipant · NL
ENVIRONMENTAL RESOURCES MANAGEMENT LIMITEDparticipant · UK
CLANCY HAUSSLER RITAparticipant · AT
AVANTIUM SUPPORT BVthirdparty · NL
MATIS OHFparticipant · IS
AVANTIUM CHEMICALS BVparticipant · NL
Fermentationexperts ASparticipant · DK
NRG PALLAS BVparticipant · NL
STICHTING WAGENINGEN RESEARCHparticipant · NL

How to reach the team

Teknologisk Institut, Denmark — search for MacroFuels project coordinator at DTI

Order a report on this consortium See TEKNOLOGISK INSTITUT profile →

Next steps

Talk to the team behind this work.

Want to explore seaweed biofuel technology for your transport fuel supply chain? SciTransfer can connect you with the MacroFuels research team and help evaluate fit for your operations.

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