In a promising development for the renewable energy sector, researchers have demonstrated a viable pathway to produce synthetic aviation fuel (SAF) from algae grown in wastewater. The study, led by Abhishek Kumar of the Pacific Northwest National Laboratory in Richland, Washington, presents a combined experimental and techno-economic assessment of the process, offering insights into its commercial potential.
The research, published in the journal “Energy Conversion and Management: X,” focuses on hydrothermal liquefaction (HTL), a process that can convert wet feedstock slurries like algae into a carbon-enriched biocrude. This biocrude can then be further processed into various distillate fuels, including SAF. The study highlights the potential of algae grown as a byproduct of wastewater treatment, which could significantly reduce the cost of feedstock for biofuel producers.
“Algae grown as a service shifts the value to the service rather than its sole use as a feedstock,” Kumar explained. “This could enable the provision of algal biomass at low to no cost to biofuel producers.”
The study found that the average minimum fuel selling price for fuels from wastewater-grown algae was $9.04 per gasoline gallon equivalent (GGE). However, this price could vary significantly based on several factors. “Adjusting estimations in the process scale, algae yield, and capital cost estimation can lower the price to $6.51/GGE or raise it to $13.07/GGE,” Kumar noted.
The research also identified opportunities for process improvements, which could enhance the economic viability of the pathway. For instance, the sale of co-products such as struvite fertilizers and cement additives could add revenue and reduce the net cost of the fuel.
The findings of this study could have significant implications for the energy sector. As the demand for sustainable aviation fuels continues to grow, the development of cost-effective and scalable production pathways becomes increasingly important. The use of wastewater-grown algae for SAF production not only provides a renewable energy source but also offers a solution for nutrient recovery and wastewater treatment.
Moreover, the study’s techno-economic assessment provides valuable insights into the factors that influence the selling price of the fuel, guiding future research and development efforts. As Kumar put it, “Ultimately, the selling price is influenced by the scale of the HTL processing facility.”
In the broader context, this research contributes to the ongoing efforts to diversify the sources of renewable energy and reduce the carbon footprint of the transportation sector. By demonstrating a viable pathway for SAF production from wastewater-grown algae, the study opens up new possibilities for the commercialization of algae-based biofuels and the integration of wastewater treatment with renewable energy production.
As the energy sector continues to evolve, research like this plays a crucial role in shaping the future of renewable energy. By providing a comprehensive assessment of the technical and economic aspects of SAF production from wastewater-grown algae, this study offers a roadmap for future developments in the field.