Scientists have developed a promising renewable fuel source that could power ships and aircraft without petroleum, yet the technology remains grounded by inconsistent government investment, regulatory barriers, and a market structure that favors fossil fuels over sustainable alternatives.
Researchers at Woods Hole Oceanographic Institution in Woods Hole, Mass., have spent years perfecting kelp-based biofuel through a process called hydrothermal liquefaction, which uses heat and pressure to convert seaweed into usable fuel. The work represents a potential breakthrough for transportation sectors—ships and aircraft—that remain heavily dependent on liquid fuels derived from oil and gasoline, which emit carbon dioxide when burned.
"We need other sources of energy that are sustainable, we can't just rely on petroleum," said Scott Lindell, a marine scientist at Woods Hole. "There's hardly anything simpler, or anything that grows quite as fast and as sustainably, as seaweed."
Yet progress has stalled dramatically since federal funding ended. Lindell's MARINER funding, or Macroalgae Research Inspiring Novel Energy Resources, lasted six years and finished in 2024. Since then, federal research funding opportunities have been fewer and delayed, illustrating a broader pattern of inconsistent government commitment to renewable energy development.
The Promise of Ocean-Based Renewables
Unlike corn-derived ethanol—the dominant biofuel additive—kelp offers distinct advantages. Corn crops require agricultural land, fresh water, and pesticides. Kelp grows in the ocean with minimal resource inputs. 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 MARINER program included projects ranging from developing heat-resistant kelp strains that can withstand warming oceans to studies on seaweed genomes. The Department of Energy, which backed the exploratory, high-risk high-return project, saw researchers make measurable progress, including increasing kelp yields.
However, the history of federal biofuel investment reveals a troubling pattern. A similar feasibility-testing venture began in the 1970s and was swiftly terminated once oil prices stabilized. In 2016, a Department of Energy program set out to develop tools for kelp-based biofuel production, yet that commitment has not been sustained.
"I don't think things have changed incredibly since the first oil crisis," Lindell said. "We'll come to the realization that things have shifted in the marketplace, and we can't squeeze any more oil out of the earth in 30 years' time."
Market Barriers Prevent Scale-Up
Beyond funding gaps, the kelp-to-fuel industry faces structural economic obstacles. 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 of kelp, selling most of it to local restaurants and seafood markets. His 9-acre farm is hundreds of times smaller than what would be needed to produce biofuel.
"The buyers come in and out, it's pretty discouraging," Dixon said. Without proven demand from the energy sector, he has no plans to expand.
Bren Smith, an ocean farmer and co-founder of GreenWave, a nonprofit supporting ocean farmers, identified the core problem: kelp is currently more viable in products like cosmetics or food, rather than fuel, which remains one of its lowest-value uses. The issue is not a lack of demand but where kelp makes sense economically.
"We've made this mistake before, right?" Smith said, referring to large-scale investments in kelp research focused on fuel production. "Competing with the most technically advanced, subsidized industry on the globe, the fossil fuel industry."
Regulatory Hurdles Limit Expansion
Even with a guaranteed buyer, expanding kelp farming would face substantial regulatory obstacles. 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 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.
"We don't yet have a full understanding of what all the ecological side effects of very large-scale ocean farming might be," said Hauke Kite-Powell, an engineer and economic analyst at Woods Hole and an ocean industry policy expert.
The Path Forward Remains Uncertain
Scientists like Lindell remain confident their work will eventually be applied to a biofuel industry. Lindell's lab continues to study and breed its collection of over 2,600 kelp strains in hopes the energy industry will transition to renewable sources. Volatile fuel prices and the finite nature of resources like oil point to an eventual change, he argues.
However, without sustained federal investment, clear regulatory pathways, and market incentives that level the playing field against entrenched fossil fuel interests, the transition from laboratory success to commercial viability remains distant.
Why This Matters:
The stalling of kelp-based biofuel research illustrates a critical policy failure: the absence of sustained, long-term government commitment to renewable energy infrastructure. Transportation accounts for a substantial portion of global emissions, yet ships and aircraft lack the electrification pathways available to automobiles. A proven, ocean-based renewable fuel source represents a potential solution to this gap—yet it languishes due to inconsistent funding and regulatory structures that favor incumbent fossil fuel industries. The regulatory barriers facing domestic aquaculture, combined with the unwillingness to subsidize renewable fuels at levels comparable to fossil fuel support, reflect a structural inequality in how the economy values short-term extraction over long-term sustainability. Without deliberate policy intervention—sustained research funding, streamlined permitting for ocean farming, and market mechanisms that account for the true cost of carbon emissions—renewable alternatives will continue to lose ground to entrenched energy interests, perpetuating dependence on finite resources and climate-destabilizing fuels.