Airlines push to reduce carbon footprint with greener fuels
Can the world’s jet fuel ever be green?
Under pressure to reach net-zero greenhouse gas emissions by 2050, airlines are experimenting with so-called sustainable aviation fuels, or SAF. The most advanced contender is biofuel, mainly made from cooking oil, animal fats, agricultural crops and unused wood, though it is a struggle to use on more than a small fraction of flights because of the lack of supply and the high costs. In the coming decade, different types of alternative fuels could make flying even cleaner.
SAF are imitations of kerosene, the refined petroleum that has burned in jet engines for decades. Different types of SAF exist, but only biofuel is in use today. Biofuel reduces emissions by up to 80% versus conventional jet fuel. International standards allow carriers to burn up to 50% biofuel with kerosene, but a recent test from U.K. engine maker Rolls-Royce and energy company Royal Dutch Shell showed that 100% biofuel is safe.
