Boeing has carried out the world's first flight using "green diesel," a widely available sustainable biofuel already used in ground transportation. The company powered its ecoDemonstrator 787 flight test airplane on Tuesday with a blend of 15 percent green diesel and 85 percent petroleum jet fuel in the left engine.
Sustainable green diesel is made from vegetable oils, waste cooking oil and waste animal fats. Boeing previously found that this fuel is chemically similar to HEFA (hydro-processed esters and fatty acids) aviation biofuel approved in 2011. Green diesel is chemically distinct and a different fuel product than "biodiesel," which also is used in ground transportation.
With production capacity of 800 million gallons in the U.S., Europe and Asia, Boeing says green diesel could rapidly supply 1 percent of global jet fuel demand. With a wholesale cost of about $3 per gallon, inclusive of U.S. government incentives, green diesel approaches price parity with petroleum jet fuel. It is yet to be seen how this could be scaled to constitute a more significant proportion of overall fuel usage.
On a lifecycle basis, green diesel reduces carbon emissions by 50 to 90 percent compared to fossil fuel, according to Finland-based Neste Oil, which supplied green diesel for the ecoDemonstrator 787. The flight test was coordinated with the U.S. Federal Aviation Administration, Rolls-Royce and Pratt & Whitney, and EPIC Aviation blended the fuel.
Green diesel is among more than 25 new technologies being tested by Boeing's ecoDemonstrator Program aboard 787 Dreamliner ZA004. The program accelerates the testing, refinement, and use of new technologies and methods that can improve aviation's environmental performance.
Earlier this year, Boeing, South African Airways (SAA) and SkyNRG announced a partnership to make sustainable aviation biofuel from a new type of tobacco plant. The initiative builds on cooperation between Boeing and SAA to develop renewable jet fuel in ways that support South Africa's goals for public health as well as economic and rural development. The organizations say that, by using hybrid tobacco, they can leverage knowledge of tobacco growers in South Africa to grow a marketable biofuel crop without encouraging smoking.