Kelp could someday power ships and aircraft without petroleum, but the people trying to make that happen are running into the same old machinery of delay, subsidy, and control. At Woods Hole Oceanographic Institution in Woods Hole, Mass., scientists are studying kelp and other seaweed as part of efforts to develop sustainable biofuels for American transport, even as they acknowledge serious hurdles before the seaweed can become a viable fuel source.
Who Gets to Decide What Counts as Energy
The process at the center of the work is hydrothermal liquefaction, which uses heat and pressure to produce fuel from kelp. Scott Lindell, a marine scientist at the Woods Hole Oceanographic Institution about a 90-minute drive south of Boston, said, “We need other sources of energy that are sustainable, we can’t just rely on petroleum,” and added, “There’s hardly anything simpler, or anything that grows quite as fast and as sustainably, as seaweed.”
The article says electricity from solar and wind can power cars, but ships and aircraft largely run on liquid fuels made with a large percentage of oil or gasoline, which emit carbon dioxide when burned. Biofuel refined from organic material like plants or algae is presented as a possible alternative. Existing biofuels such as corn-derived ethanol mainly work as gasoline additives, and corn crops require agricultural land, fresh water and pesticides, while kelp can be grown in the ocean with minimal resources. The article says any bioethanol, whether produced from corn or kelp, releases hazardous gases when burned, such as acetaldehyde, but produces fewer greenhouse gases overall than petroleum-based fuels.
Researchers including Lindell have bred kelp varieties that in some cases produce up to three times more biomass than conventional strains. Around Lindell’s lab are glass vials and flasks of over 2,600 strains of sugar kelp collected from across New England, which he continues to study and breed selectively. The article says Lindell’s MARINER funding lasted six years and finished in 2024. MARINER, or Macroalgae Research Inspiring Novel Energy Resources, included projects ranging from developing heat-resistant kelp strains that can withstand warming oceans to studies on seaweed genomes. The Department of Energy often backs exploratory, high-risk high-return projects, and researchers involved in MARINER said they made progress, including increasing kelp yields. The program mirrored a similar feasibility-testing venture that began in the 1970s and was swiftly terminated once oil prices stabilized.
The Funding Comes and Goes
The article says government interest in biofuels has been inconsistent. In 2016, a Department of Energy program set out to develop tools for kelp-based biofuel production. Since Lindell’s MARINER funding ended in 2024, federal research funding opportunities have been fewer and delayed. Lindell said, “I don’t think things have changed incredibly since the first oil crisis.” He also said, “We’ll come to the realization that things have shifted in the marketplace,” and, “and we can’t squeeze any more oil out of the earth in 30 years’ time.”
That stop-start pattern leaves the work dependent on institutions that can fund it when convenient and abandon it when the market changes. The article says a middle market for kelp has yet to materialize. Aquaculture farms today remain small, supplying kelp primarily to restaurants, cosmetics companies and fertilizer producers.
Oliver Dixon, a shellfish farmer based in Point Judith, Rhode Island, grows kelp to supplement his oyster business during the winter. As of this month, he expects to harvest about 10,000 pounds (4,500 kilograms) of kelp, selling most of it to local restaurants and seafood markets. Dixon said, “The buyers come in and out, it’s pretty discouraging.” His 9-acre (3.6-hectare) farm is hundreds of times smaller than what would be needed to produce biofuel, and without proven demand from the energy sector, he has no plans to expand.
Small Farms, Big Barriers
Bren Smith, an ocean farmer and co-founder of GreenWave, a nonprofit supporting ocean farmers, said the issue is not a lack of demand but where kelp makes sense economically. He said kelp is currently more viable in products like cosmetics or food, rather than fuel, which remains one of its lowest-value uses. Smith said, “We’ve made this mistake before, right?” and, referring to large-scale investments in kelp research focused on fuel production instead of other uses, added, “Competing with the most technically advanced, subsidized industry on the globe, the fossil fuel industry.”
Even with a guaranteed buyer, expanding kelp farming would face regulatory hurdles. In the United States, coastal waters are largely prioritized for recreation, fishing and conservation, making it difficult to obtain permits for large aquaculture projects. By contrast, countries in Asia often prioritize extensive seaweed farms, sometimes covering entire bays. Dixon said he cannot obtain a permit to keep his farm infrastructure in the water year-round, requiring him to remove his lines and anchors each spring and reinstall them in the fall.
Moving farms further offshore could allow for larger operations, but it introduces engineering and environmental challenges, including the risk of entangling marine animals and the possibility that farmed kelp could compete with other marine life for nutrients. Hauke Kite-Powell, an engineer and economic analyst at Woods Hole and an ocean industry policy expert, said, “We don’t yet have a full understanding of what all the ecological side effects of very large-scale ocean farming might be.”
The article says scientists like Lindell remain confident their work will eventually be applied to a biofuel industry. Lindell’s lab has more than 2,600 strains of sugar kelp from across New England, and he continues to study and breed them in hopes the energy industry will transition to renewable sources. He said volatile fuel prices and the finite nature of resources like oil point to an eventual change.