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GE Aerospace and its partners are celebrating a milestone in sustainable flight after completing tests on 10 different aircraft engines using 100 percent SAF. The testing confirmed that the company and its joint ventures have one of the most expansive programs to test alternative fuel in the industry.
Since 2016, GE and its partners tested 10 different engines made by the company, including a mix of component-, engine- and aircraft-level tests. These tests will support the industry-wide effort to achieve net zero CO2 emissions by 2050. In 2018, GE90 engines powered the first commercial airliner flight with 100 percent SAF in both engines on the Boeing ecoDemonstrator, a 777 freighter in partnership with FedEx Express. In 2021, LEAP-1B engines powered the first passenger experimental flight using 100 percent SAF in one of the two engines on a United Airlines Boeing 737-8. In 2023, LEAP-1B engines powered test flights using 100 percent SAF in both engines of the Boeing ecoDemonstrator Explorer, a 737-10 headed to United Airlines, as a part of emission testing with NASA. In November, Emirates became the first airline to operate an Airbus A380 using 100 percent SAF in one of the four GP7200 engines.
Other testing at the component-, engine- or aircraft-level using 100 percent SAF has been conducted on F414, GE9X, LEAP-1A, Passport, GEnx, HF120 and CFM56 engines. The variety of tests represents a mix of propulsion systems for both domestic and international commercial air travel, military aviation, and business and general aviation. The testing has evaluated a range of factors including engine performance and the impact of SAF use on contrails and emissions. GE Aerospace and its many joint ventures power three out of every four commercial flights globally. The CFM56 and LEAP engines tested are a product of CFM International, a joint company between GE and Safran Aircraft Engines. The GP7200 engines are a product of Engine Alliance, a 50-50 joint company between GE and Pratt andamp;Whitney. The HF120 engines are a product of GE Honda Aero Engines LLC, a joint company between GE and Honda Aero.
"These tests demonstrate that we are leading and prepared to support our customers to operate on Sustainable Aviation Fuel," GE Aerospace VP of Engineering Mohamed Ali said. "We're proud of doing the hard work to better understand the impact of different emissions on the environment and using science to guide the technology we are developing to invent the future of flight."
To qualify for new 100 percent SAFs, GE is testing each engine system, from the engine component to sub-component level evaluations. The testing will cover the components exposed to and impacted by fuels, including the engine fuel system and combustor where fuel is burned. Different types of SAF are produced from differing pathways and these types are tested to assess whether there is an impact on engine operability, efficiency, durability and emissions.
In November, international governments gathered at the third ICAO Conference on Aviation and Alternative Fuels (CAAF/3). A goal was set for aviation fuel in 2030 to be five percent less carbon-intensive than conventional jet fuel. This decision follows a previous statement made by seven CTOs of major aviation manufacturers, including GE, calling for supportive government policies to hasten the availability and adoption of qualified SAF. The statement included CTOs from Airbus, Boeing, Dassault Aviation, Pratt andamp; Whitney, Rolls-Royce and Safran.
"Increasing the production and utilization of SAF is a critical step for achieving the air transportation sector's net zero CO2 emissions goal by 2050," the joint statement read. "However, the production of SAF is currently estimated at less than 0.1% of the global demand for jet fuel today. Moreover, SAF prices are typically two to five times higher than the price of conventional jet fuel. The supply is further constrained by competition for renewable fuels from other sectors that have alternative decarbonization options, such as with surface transportation and heating."RELATED STORY:SAF production doubled this year, projections for 2024 fall short of rising demands
The International Air Transport Association recently released a report on the volume projections for SAF in the coming years. Between 2022 and 2023, the SAF volume doubled. The projected production of SAF in 2024 is expected to triple, but the increase would only account for half of the industry's fuel needs. Meeting these needs requires significant time and research to expand SAF production efficiently and cost-effectively. GE said that meeting long-term net-zero goals requires the industry to use new technologies to increase engine fuel efficiency.
To address the challenges facing SAF production, GE has numerous demonstrators underway, including the CFM RISE program in partnership with Safran and the Electrified Powertrain Flight Demonstration project with NASA. The CFM RISE program targets a more than 20 percent better fuel efficiency with 20 percent lower CO2 emissions compared to most engines in service today. Open fan engine architecture and hybrid-electric systems are in development and designed to be compatible with 100 percent SAF.
To meet the growing demand for SAF production, continued research and investments into new strategies, production pathways and feedstocks, government policies and infrastructure are necessary. All GE engines and partner engines can operate on approved SAF blends, which are made from plant-based material, fats, oils and greases, alcohols, waste streams or captured CO2. Unlike fossil-based sources, SAF is made from partially or completely renewable sources, allowing for a reduction in CO2 emissions over a fuel's life cycle.
Current approved SAF is a synthetic component blended with petroleum-based Jet A or Jet A-1 fuel up to 50 percent. The industry is preparing for the eventual integration of 100 percent drop-in SAF, conducting testing and developing standardized industry specifications to support the adoption. Engine testing will provide crucial data to support the development of 100 percent SAF standards and the approval of 100 percent drop-in SAF use.