The National Academies of Sciences, Engineering, and Medicine Transportation Research Board has released a flagship report on the air quality impacts of sustainable alternative jet fuel (SAJF) emissions. The report is based in part on reviews by Missouri University of Science and Technology faculty Dr. Philip D. Whitefield, chair and professor of chemistry and director of the Center for Research in Energy and Environment (CREE), and Dr. Donald E. Hagen, professor emeritus of physics.
Whitefield and Hagen are scholars in the field of aviation emissions. Their aircraft emissions analysis within a Missouri S&T research team was integral to the work of the Intergovernmental Panel on Climate Change (IPCC) that jointly received the 2007 Nobel Peace Prize with Albert Arnold (Al) Gore Jr.
“This state of the industry report is the first review of its kind,” says Whitefield, S&T’s lead investigator. “It lays the groundwork to define the environmental impact of SAJF emissions on air quality in and around airports throughout the world and gives them the information they need to start determining strategies for switching to alternative jet fuels.”
SAJFs are a family of synthetically made fuels intended to lower the life cycle of carbon emissions of commercial aviation that can be used within the existing U.S. fuel distribution system without making engine modifications. To date, five different SAJF fuel production pathways have been defined by the aviation industry in ASTM D7566 as safe for use in commercial aircraft, and more are under review.
One of the main purposes for airlines to use SAJFs is to reduce criteria pollutants categorized in legislation such as the Clean Air Act. These include carbon monoxide, sulfur dioxide, nitrogen oxide, particulate matter (soot), unburnt hydrocarbons and hazardous air pollutants.
“Until this report, these reductions had not been well-defined,” says Whitefield. “Airlines are also constrained by emissions limits set by the EPA and must make sure that by using SAJFs they will not receive fines.”
The “State of the Industry Report on Air Quality Emissions from Sustainable Alternative Jet Fuels” distills the current knowledge of emissions data from 51 reports of SAJF quantitative emissions analyses. The report’s content comes from projects sponsored by federal agencies, the aviation industry and academia, Whitefield notes.
The report aims to improve current understanding of local air quality emissions benefits and the impacts of SAJFs and SAJF blends relative to conventional jet fuel, Whitefield notes. Its data summary shows that when blended with conventional jet fuels defined by ASTM international standards, SAJFs:
“Our review is based on responsible and interdisciplinary science aimed at reducing criteria pollutant and greenhouse gas (GHS) emissions in and around airports,” Whitefield says. “All evidence suggests that the use of SAJFs will substantiate reductions in pollutants emissions.”
Based on projected growth of the aviation industry, other drivers for the use of alternative jet fuels include domestic energy security, diversity of fuel supplies, less fuel price volatility, lower long-term fuel cost and ancillary benefits of growth of a bioeconomy with associated job creation, according to the U.S. Department of Energy.
The “State of the Industry Report on Air Quality Emissions from from Sustainable Alternative Jet Fuels” was submitted to the Transportation Research Board by the Booz Allen Hamilton consulting firm in association with Missouri S&T, the Environmental Consulting Group and Conska Aviation Consultancy. The work was conducted in the Airport Cooperative Research Program, which is administered by the Transportation Research Board of the National Academies of Sciences, Engineering, and Medicine.