Airlines Ramp Up Green Jet Fuel, But Their Emissions Keep Rising

British Airways’ parent company IAG SA surged ahead of other passenger airlines last year to consume the most sustainable aviation fuel, or SAF, according to a Bloomberg Green review of corporate filings from dozens of air carriers.

The company acquired 55 million gallons of cleaner jet fuel, which is derived from lower-emitting sources such as used cooking oil and animal tallow. That number exceeded the amount used by all US passenger airlines combined.

But the promising performance is overshadowed by a troubling reality for the industry: The shift to SAF is still minuscule, while growth in passenger air travel is ...