Caribbean Innovation

Barbados Is Running Cars on Sargassum. Here's How a UWI Spin-Off Made It Work

By Innovation Report | May 2026

Key Points

✓ Since 2011, sargassum seaweed has become a recurring coastal crisis across Caribbean islands, with Barbados filling over 800 dump trucks on a bad day. One beach resort was spending US$2 million a year on removal from a single beach, and the cost burden falls on governments, tourism operators, and disaster management budgets across the region.
✓ Rum and Sargassum Inc., a spin-off from the University of the West Indies (UWI) Cave Hill campus in Barbados, has demonstrated that sargassum combined with rum distillery wastewater can be converted into Bio-CNG, a renewable compressed natural gas chemically identical to fossil fuel natural gas. Standard vehicles can be converted to run on it with a simple kit installed in around four hours, with no need to purchase new vehicles.
✓ Proof-of-concept test drives have been completed in Barbados and Grenada, with four CNG conversion kits installed in vehicles. A pilot Bio-CNG fuelling station is currently under construction in Barbados and would be the Caribbean's first dedicated Bio-CNG transport fuel supply when operational.
✓ The company was founded in 2021 by Dr Legena Henry, a mechanical engineer and lecturer at UWI Cave Hill, following an idea first proposed by undergraduate student Brittney McKenzie. The project has since been covered by Nature, MIT Technology Review, and the BBC World Service. UWI Vice-Chancellor Professor Sir Hilary Beckles has identified scaling the technology as a strategic priority for the university's commercialisation programme, with the eastern Caribbean's shared sargassum and rum wastewater streams making regional expansion a realistic next step.

Every bad sargassum season, the same thing happens on Barbados's tourist beaches. Brown walls of seaweed roll in off the Atlantic, pile up on the sand, and start rotting in the heat. Resorts deploy crews to haul it away, loading dump truck after dump truck. One property was spending US$2 million a year on the problem. On the worst days, the island fills over 800 trucks' worth of the stuff before it can be cleared.

It was a student commuting past those mounds of rotting seaweed who asked the question that became the foundation of a company. Brittney McKenzie, then an undergraduate in Dr Legena Henry's renewable energy course at the University of the West Indies Cave Hill campus, suggested they look at sargassum as a potential biofuel feedstock. The year was 2019. Barbados had just committed to becoming fossil-fuel-free by 2030, and the team had already ruled out copying Brazil's sugar-cane ethanol model: the island's sugarcane volumes were too low, and its distilleries had long since switched to imported molasses.

What happened in the lab surprised everyone. Henry, a mechanical engineer with a master's from MIT and a doctorate from UWI, mixed sargassum with wastewater from a rum distillery and ran the experiments. Microbes in the wastewater fed on the sugar and digested the seaweed. The result was biomethane. Something that Henry had expected might produce a publishable paper instead became the basis for Rum and Sargassum Inc., a UWI Cave Hill spin-off company founded in 2021 and now building what would be the Caribbean's first Bio-CNG transport fuel supply.

How Bio-CNG from Sargassum and Rum Waste Works

The core process is anaerobic digestion, the same microbial breakdown that produces biogas from agricultural waste and food scraps in many countries. What makes the Barbados approach distinctive is the particular combination of feedstocks: sargassum provides the solid organic material for digestion, while rum distillery wastewater contributes a sugar-rich liquid that accelerates microbial activity. Manure from local Blackbelly sheep is sometimes added to the mix as well, introducing additional methane-producing microbes and nutrients that improve biogas yields.

How Bio-CNG from Sargassum Is Produced

1. Feedstock collection

Sargassum is collected from beaches and coastal waters. Rum distillery wastewater, which is abundant across the Caribbean, provides the liquid co-digestate. Blackbelly sheep manure is sometimes added to improve yields.

2. Anaerobic digestion

The seaweed and wastewater are combined in a sealed digester. Microbes in the wastewater feed on residual sugars and break down the sargassum, producing raw biogas (primarily methane and carbon dioxide).

3. Upgrading to Bio-CNG

Raw biogas is refined and compressed into Bio-CNG, which has the same chemical composition and energy characteristics as fossil fuel compressed natural gas.

4. Vehicle fuelling

Standard petrol or diesel vehicles receive a CNG conversion kit in a four-hour installation. They can then fill up at a Bio-CNG station in around three minutes, with no engine redesign required.

The chemistry matters because it determines the fuel's practicality. Bio-CNG is a direct drop-in for fossil fuel natural gas, meaning it does not require purpose-built vehicles or new engine designs. It burns in any CNG-converted internal combustion engine without modification. For an island trying to decarbonise transport without asking residents to buy new electric vehicles, that distinction is significant. Caribbean households cannot, in the main, absorb the upfront cost of EV transition. A retrofitted car, converted in an afternoon, changes that calculation.

As Dr Henry explained following recent test drive events: "By converting invasive Sargassum seaweed and rum distillery wastewater into renewable natural gas, an exact drop-in for fossil fuel natural gas, we're tackling both climate change and coastal pollution."

From Lab Result to CNG Kits in Barbados and Grenada

The distance between a promising lab result and a working fuel supply is rarely short. For Rum and Sargassum Inc., the proof-of-concept stage took the team through five years of iterative development before the quality of the fuel product was sufficient for vehicle use. UWI Vice-Chancellor Professor Sir Hilary Beckles has described those years as "pretty hard work," telling Innovation Report in a recent interview that the team now has a sargassum biofuel capable of powering standard cars with a simple carburettor adjustment.

The first public demonstrations moved the project out of the laboratory and onto the road. In Barbados, four CNG conversion kits were installed in petrol and diesel vehicles. A separate event at the Second European Union-Caribbean Global Conference on Sargassum in Grenada saw the biofuel powering a portable generator that charged an electric vehicle, a configuration designed to show the technology's potential role in a broader clean energy chain.

A pilot Bio-CNG fuelling station is currently under construction, staffed partly by volunteers. When operational, it will be the first facility of its kind in the Caribbean dedicated to transport fuel from sargassum and agricultural waste streams. The company is simultaneously seeking investment and scale partnerships to move the technology beyond Barbados. As Dr Henry noted when speaking to Nature in November 2024: "All the islands in this region of the Caribbean have a sargassum problem and a rum wastewater problem, and ultimately a climate-change problem. This solution is a win-win-win."

Sargassum as a Regional Fuel Feedstock, Not Just a Coastal Nuisance

Sargassum has been washing up on Caribbean shores in quantities that were barely recorded before 2011. Since then it has become a recurring crisis across the Lesser Antilles, the Gulf of Mexico, and as far north as Florida. The seaweed is pelagic, meaning it grows and floats in open water rather than attaching to the seafloor, and the Great Atlantic Sargassum Belt now spans thousands of kilometres. Barbados sits in the path of the Atlantic circulation that concentrates the blooms on its eastern and southern coasts.

The standard response has been mechanical removal: trucks, tractors, and manual labour, followed by disposal in landfill. The costs are borne by resorts, municipal governments, and national disaster management budgets. Converting sargassum from a disposal problem into a feedstock reframes the economics. Instead of paying to remove it, coastal communities could eventually be paid to collect it, or at minimum see the costs of removal offset by the fuel it generates.

The challenge is that sargassum's chemical composition complicates digestion. It contains higher concentrations of heavy metals and halogenated compounds than many terrestrial biomass feedstocks, which can inhibit microbial activity and require pre-treatment. The UWI team's use of rum distillery wastewater as a co-substrate appears to address part of this problem by providing a microbial community already adapted to high-sugar, high-organic conditions. Early results suggested the sargassum-wastewater combination significantly outperformed other biomass feedstocks available in Barbados, including grasses grown specifically for biofuel production.

The Blackbelly sheep manure that sometimes enters the mix is not incidental. Blackbelly sheep are the indigenous breed of Barbados and are farmed across the island. Adding their manure introduces additional methane-producing microbes and nutrients that can improve biogas yields during digestion. It is the kind of systems-level thinking that characterises the project: every input is a local waste stream, every output is a local fuel.

UWI, MIT, and the Institutional Backing Behind the Company

Rum and Sargassum Inc. operates as a formal spin-off of the University of the West Indies Cave Hill campus, which is itself part of the Caribbean's only regional federal university, jointly funded by 17 sovereign governments. UWI's decision a decade ago to become an entrepreneurial institution, targeting 30% of operational costs from commercialised research, has created the structural conditions in which a project like this can move from undergraduate question to funded start-up.

Dr Henry brings a combination of regional and international technical formation to the project. Her master's in mechanical engineering from MIT, completed in 2010, gave her exposure to multidisciplinary engineering research at scale. Her doctorate from UWI, and her ongoing lectureship at Cave Hill, grounds the work in Caribbean institutional infrastructure. The original research team from the 2019 summer project included Karyl Pivott, Kristen Lynch, Aria Goodridge, Brittney McKenzie, and Joshua Austin, representing the undergraduate pipeline through which UWI channelled student curiosity into applied research.

Nature, MIT Technology Review, and the BBC World Service have all covered the project. Professor Sir Hilary Beckles told Innovation Report that scaling the sargassum biofuel remains one of UWI's stated priorities at the commercialisation stage, with the university actively looking for an investment partner capable of moving the technology out of the pilot phase and into regional markets. The pilot station under construction in Barbados is the immediate next step; a network of Bio-CNG stations across the eastern Caribbean would follow if the investment and logistics fall into place.

Frequently Asked Questions

What is Bio-CNG and how is it made from sargassum?

Bio-CNG (Bio-Compressed Natural Gas) is renewable natural gas produced by anaerobic digestion of organic material. Rum and Sargassum Inc. produces it by combining sargassum seaweed with rum distillery wastewater in a sealed digester, where microbes break down the feedstocks to produce raw biogas. That gas is then upgraded and compressed into a fuel chemically identical to fossil fuel compressed natural gas.

Can standard vehicles run on sargassum Bio-CNG?

Yes. Standard petrol and diesel vehicles can be converted to run on Bio-CNG with a CNG conversion kit, which Rum and Sargassum Inc. states takes approximately four hours to install. Because Bio-CNG is chemically equivalent to fossil fuel natural gas, it does not require purpose-built vehicles. Converted vehicles fill up at a CNG fuelling station in around three minutes.

Where has sargassum biofuel been demonstrated so far?

Proof-of-concept test drives have taken place in Barbados and Grenada. Four CNG conversion kits have been installed in vehicles in Barbados. A pilot Bio-CNG fuelling station is currently under construction in Barbados and, when operational, will be the Caribbean's first Bio-CNG transport fuel supply. The company is in the investment phase to scale the technology across the eastern Caribbean.

Who founded Rum and Sargassum Inc. and what is its relationship to UWI?

Rum and Sargassum Inc. was founded in 2021 by Dr Legena Henry, a mechanical engineer and lecturer at the University of the West Indies Cave Hill campus in Barbados. It is a formal spin-off of the UWI Cave Hill campus, operating within UWI's strategic programme to convert research into commercial products. The original research was carried out by Dr Henry and a team of undergraduates in 2019, following an idea first proposed by student Brittney McKenzie.

Why is sargassum such a serious problem for Caribbean islands?

Since around 2011, the Great Atlantic Sargassum Belt has produced large-scale blooms that wash onto Caribbean beaches seasonally, causing tourism disruption, beach closures, and marine ecosystem damage. On a bad day in Barbados, sargassum fills over 800 dump trucks. One resort was spending US$2 million per year removing it from a single beach. Disposal in landfill has been the primary response, at significant cost to governments and private operators across the region.

Sources and further reading: Rum and Sargassum Inc. | Nature, November 2024 | MIT Technology Review, February 2025 | BBC World Service | Interview with Professor Sir Hilary Beckles, Innovation Report, April 2026