A team at yhe Universiy of Georgia has estimated the break-even price and life cycle carbon emissions of sustainable aviation fuel (SAF) derived from oil obtained from Brassica carinata—a non-edible oilseed crop—in the Southeastern United States. The open-access study is published in GCB Bioenergy.

Carinata has the potential as a feedstock for SAF production in the Southeastern US due to higher yield, low fertilizer use, co-product generation (animal feed, propane, and naphtha), and compatibility with current farming practices, the researchers said. The system boundary for the life cycle analysis (LCA) started at the farm and ended when the SAF is delivered to an airport.

Among the top findings:

• Without co-product credit or other subsidies such as Renewable Identification Number (RIN) credit, carinata-based SAF was more expensive ($0.85 L⁻¹ to $1.28 L⁻¹) than conventional aviation fuel ($0.50 L⁻¹).

• With co-product credit only, the break-even price ranged from $0.34 L⁻¹ to $0.89 L⁻¹.

• With both co-product and RIN credits, the price ranged from -$0.12 to -$0.66 L⁻¹.

• The total carbon emission was 918.67 g CO₂e L⁻¹ of carinata-based SAF. This estimate provides 65% relative carbon savings compared with conventional aviation fuel (2618 g CO₂e L⁻¹).

• Sensitivity analysis suggested a 95% probability that relative carbon savings can range from 61% to 68%.

Our study indicates that carinata-based aviation fuel could significantly reduce carbon emissions of the aviation sector. However, current policy support mechanisms should be continued to support manufacturing and distribution in the Southeastern United States.

—Alam et al.

Resources

• Alam, A., Masum, M. F. H., & Dwivedi, P. (2021). “Break-even price and carbon emissions of carinata-based sustainable aviation fuel production in the Southeastern United States.” GCB Bioenergy, 13, 1800– 1813. doi: 10.1111/gcbb.12888