THE USE of biofuels in air transport continues to evolve, with several big developments in the area in recent weeks.
On October 3, Virgin Atlantic Airways undertook the first commercial flight using a new form of jet fuel. Flight VS16 from Orlando to London Gatwick, operated by a Boeing 747-443, G-VROM (c/n 32339), flew with a mix of conventional Jet A-1 and fuel produced using recycled waste carbon gases.
The biofuel was supplied by LanzaTech, a Chicago-based company that recycles ethanol waste gases produced by heavy industrial processes such as steelmaking. This ethanol undergoes a catalytic process to be upgraded to an alcohol-to-jet synthetic paraff nic kerosene (ATJ-SPK) fuel that can then be mixed with conventional Jet A-1.
The process used to make ATJSPK was developed by LanzaTech in collaboration with the Pacific Northwest National Laboratory (PNNL), a US Department of Energy (DOE) research lab.
A PNNL statement explained the carbon recycling technology operates in a similar way to a traditional fermentation process: “but instead of using sugars and yeast to make alcohol, waste carbon-rich gases, such as those found at industrial manufacturing sites, are converted by bacteria to fuels and chemicals … The catalyst removes oxygen from the ethanol in the form of water, and then combines the remaining hydrocarbon molecules to form chains large enough for jet fuel without forming aromatics that lead to soot when burned.”
The PNNL claimed the Virgin Atlantic flight ushered in “a new era for low-carbon aviation” and that it has “shown the world that carbon can be recycled and used for commercial flight”.
LanzaTech scaled up the technology for the flight, converting waste ethanol to 4,000 US gallons (15,141 litres) of ATJSPK at its Freedom Pines facility in Georgia to meet all industry specifications.
Back in April 2018, an international standards body approved the LanzaTech-PNNL ethanol-based ATJ-SPK for aviation turbine fuel at up to a 50% blend ratio. The Virgin Atlantic flight was therefore a key milestone in demonstrating the technology’s maturity and potential.
LanzaTech Chief Executive Officer Jennifer Holmgren said: “Many people thought recycling waste carbon emissions into jet fuel wasn’t possible. We have shown that waste carbon is an opportunity, not a liability, and that carbon can be reused to provide sustainable benefits for all.”
John Holladay, PNNL’s Deputy Manager for energy efficiency and renewable energy, commented: “This fuel exceeds the properties of petroleum-based jet fuel in terms of efficiency and burns much cleaner. By recycling carbon already in the environment, in this case waste gas streams, it lets the world keep more petroleum sequestered in the ground. The technology not only provides a viable source of sustainable jet fuel, but also reduces the amount of carbon dioxide emitted into the atmosphere.”
The focus is now on scaling up the technology. With co-funding from the DOE’s Bioenergy Technologies Office, LanzaTech is preparing a design and engineering package for an ATJ production facility at Freedom Pines that would be able to convert sustainable ethanol to millions of gallons of low carbon jet and diesel fuels per year. The company claims that if the technology was rolled out worldwide to the world’s eligible steel mills, it could produce enough fuel to meet around 20% of the current commercial global aviation fuel demand.
The company claimed: “The fuel has a fantastic sustainability profile with at least 70% life cycle carbon savings, as well as no land, food or water competition issues … Crucially, because it’s made from plentiful, aff ordable waste streams, the fuel has a fighting chance at coming in at a price on a par with current fossil fuel prices.”
The Virgin Atlantic flight has not been the only recent significant development in the biofuels area. In September, United Airlines’ Flight 44 from San Francisco to Zurich, operated by a Boeing 787, ran on a blend of 70% Jet A-1 and 30% sustainable aviation biofuel made from Carinata oilseed supplied by the Canadian agritech company Agrisoma.
This was the longest transatlantic flight yet undertaken using biofuel and took place as United became the first airline in the United States to commit publicly to reducing its greenhouse gas emissions by 50% by 2050.
The recent Virgin 747 and United 787 demonstrations are of course only the latest commercial aircraft flights with biofuels. Since Virgin Atlantic operated the first back in February 2008, many airlines have operated flights using ‘drop-in’ fuels produced from various sources, ranging from waste cooking oil to algae and jatropha plants, blended with conventional aviation fuel.
With ICAO’s Carbon Off setting and Reduction Scheme in International Aviation looming large – airlines will have to monitor and report fuel use and emissions from January 2019 ahead of the full off set scheme coming into force – it is possible there will be more flights with biofuels as airlines explore how they can make their usage coste ff ective.