by Curlan Campbell
- HTL utilises water in feedstock, especially useful for high-moisture waste like sludge, algae, and food scraps
- Organic waste from cruise ships could be processed locally into renewable energy
- HTL could address pressing waste management challenges across SIDS like Grenada
As Caribbean nations continue to explore sustainable energy solutions, 2 regional experts are urging decision-makers to examine the feasibility of hydrothermal liquefaction (HTL) as a potential waste-to-energy technology. While opinions differ on its role in long-term energy planning, both experts agree that the process could address pressing waste management challenges across small island developing states (SIDS) like Grenada.
At the Caribbean Energy Transition Reporting Initiative workshop focused on the future of clean energy in Dominica, Dr Byron Winston, a US-based Senior Environmental Scientist and water quality expert with Caribbean roots, is championing HTL as a transformative solution. “The system I’m proposing is called hydrothermal liquefaction. It’s a big, fancy name for something very simple,” he said in a recent interview. “Hydro means water. Thermal means heat. Liquefaction loosely means turning something into liquid.”
HTL mimics the natural process of fossil fuel formation by using high heat and pressure to convert organic waste into bio-crude oil. Unlike other thermal processes, HTL utilises the water in the feedstock, making it especially useful for high-moisture waste like sludge, algae, and food scraps.
Dr Winston explained that while nature takes millions of years to turn organic material into crude oil, modern technology can now do it in under an hour. “What Mother Nature does over millions of years, we can now do in 45 minutes.”
He emphasised the potential benefits for the Caribbean, pointing out that organic waste from cruise ships could be processed locally into renewable energy. “This could be a game changer for the Caribbean, especially considering the volume of organic waste generated by cruise ships. Instead of shipping that waste back to Miami, we could be converting it into renewable energy right here.”
However, not everyone sees HTL as primarily an energy solution. Environmental engineer Charlin Bodley of St Lucia, a sustainable energy and project development expert, supports the investigation of HTL, but cautions against overselling its economic viability. “I agree with his perspective. And this is very specific to organic waste, where I may differ… is with municipal waste, and the thinking behind that is no study has demonstrated comfortably that a waste-to-energy power plant is an ideal solution for a small island developing state, and the reason being what needs to go into that system versus what comes out.”
Bodley explained that no existing research has convincingly shown waste-to-energy plants to be a practical fit for small island developing states, mainly due to the imbalance between input requirements and energy output. She noted that the cost of producing electricity through such systems remains high and unattractive. However, she acknowledged the region’s ongoing waste management challenges and suggested that the technology might be more suitable as a waste treatment solution rather than a primary energy source. “The correct scientific approach to determining whether small island developing states should pursue waste-to-energy is one that is based on science, scientific methods, numbers, figures.”
Bodley emphasised the need for detailed technical and financial modelling before proceeding with large-scale investments. “We have to run the financial models. We have to do all of that modelling because, as you know, we have other options for renewable energy technologies. Our Eastern Caribbean island states have the option of geothermal, which can single-handedly provide for their energy needs. There is solar and wind. We have so many other technologies. So ideally, through modelling, you want to understand the impact of a waste-to-energy power plant,” she continued.
Winston acknowledged the importance of thorough planning and proposed a phased approach. “We’re running into a lot of problems with waste, and we need to come up with solutions sooner rather than later,” he said. “We can look into smaller-scale waste-to-energy production…Maybe we run a hospital off it… Maybe not an entire building or community, maybe a school or something. Something that’s beneficial.”
Though currently based in the United States, Winston sees his work as part of a broader mission to give back to the region. “That’s the reason I went to the US to get the technical expertise and bring it back to the Caribbean, tailored to our unique needs.”
Both experts agree that HTL has the potential to contribute to sustainable development goals in SIDS, if approached with scientific rigour and realistic expectations.
“We don’t have a culture of tipping fees, which could help make such systems more financially viable. But again, if the funding is available for this as a waste management strategy, then why not?” asked Bodley. Tipping fees cover the expenses associated with operating and maintaining a waste disposal site.
As Caribbean leaders continue to weigh energy options in a changing climate, technologies like HTL represent both opportunity and challenge. Whether used as a renewable energy source or a waste reduction tool, its future in the region depends on science, strategy, and regional cooperation.
