Boeing Company, one of the largest aircraft manufacturers in the world, announced Tuesday that it’s seeking approval from U.S. regulators to use a blend of renewable diesel as fuel for its airliners.
The specific form of renewable diesel Boeing is interested in is produced from vegetable oils and fats, and is nearly identical to traditional petroleum-based diesel fuel at the molecular level. As a result, it’s what’s known as a “drop-in” fuel, meaning it’s friendly to existing infrastructure. It can be transported by pipeline and blended straight into existing traditional diesel supplies with little difficulty — in fact, Boeing is seeking approval for a fuel blend of up to 50 percent renewable diesel.
The company also claims the renewable diesel it’s looking at can be bought at a wholesale price of $3 per gallon, making it competitive with petroleum jet fuel. Airlines have experimented with renewable fuels before, but for the most part one disadvantage was that they were considerably more expensive.
Boeing has been working with engine makers General Electric and Pratt & Whitney, as well as the Federal Aviation Administration (FAA), to develop “drop-in” alternative fuels through the Continuous Lower Energy, Emissions and Noise program. To begin using their proposed blend, Boeing will have to get approval from ASTM International, a global standards group, whose approved specifications are then used by the FAA to set fuel standards and limitations for aircraft. If they can get the green light, the renewable diesel should be able to meet about one percent of global jet fuel demand, or about 600 million gallons.
But it’s also a piece of low-hanging fruit in the effort to prove the viability of alternative biofuels at scale. Converting 20 percent of all air travel to biofuel would require significantly less resources and biomass than an equivalent transformation of ground transportation. And the infrastructure adjustment would also be easier, since air travel is centered around 1,700 or so airports around the world, as opposed to the decentralized sprawl of ground vehicle use.