GE Aerospace researchers to build, demonstrate prototype engine with fuel cells, SAF

Following successful completion of the design phase of its FLyCLEEN project, the U.S. DOE’s Advanced Research Projects Agency-Energy has awarded GE Aerospace Research $4.5 million in Phase 2 funding to take the next step of building and demonstrating a 25-kilowatt power-generation subsystem integrating solid-oxide fuel cells with a sustainable aviation fuel (SAF)-powered gas turbine for hybrid electric propulsion.

The use of fuel cells could vastly improve the efficiency of converting the chemical energy from SAF into electric power and move closer to net-zero CO2 emissions.

John Hong, a GE Aerospace senior combustion research engineer and FLyCLEEN project leader, says the team is bringing to bear nearly two decades of experience in solid-oxide fuel-cell technology to support the development and demonstration of a high-efficiency power-generation system with lower carbon emissions.

“The integration of fuel cells into a jet-engine propulsion system represents a potentially promising hybrid technology for additional fuel-efficiency technologies in higher-thrust aircraft applications,” Hong said. “The use of SAF demonstrates the compatibility with lower-carbon fuels to capture further CO2-reduction benefits.”

Hong explained that this hybrid approach uses SAF in both the fuel cells and gas turbines.

A portion of SAF is reformed to syngas to feed the fuel cells, while the rest of the SAF is consumed in the gas-turbine engine.

This is a novel concept to combine the two.

For more details, a video with Hong explains how the FLyCLEEN system works.

“This is such an exciting time for the aerospace industry,” Hong added. “From fuel cells and SAF to advances in electric power, hydrogen, and even new engine architectures like our open-fan design, we are seeing a confluence of technologies driving progress on a number of fronts. And we will need every bit of new investments and public partnerships like we have with ARPA-E to meet the industry’s goal of net-zero CO2 emissions by 2050.”

GE Aerospace Research’s ongoing programs in hybrid-electric propulsion with ARPA-E are a great complement to the CFM RISE (Revolutionary Innovation for Sustainable Engines) program, a major technology demonstrator GE Aerospace unveiled with its 50/50 joint venture partner, Safran, in 2021.

This demonstrator program aims to deliver a 20 percent reduction in fuel consumption compared to engines today, which would represent a major step change in propulsion efficiency.

Along with advancing hybrid-electric propulsion technologies, CFM RISE also is driving advancements in hydrogen-fueled and 100 percent SAF jet engines, as well as transformational new engine architectures like an open-fan design recently featured at the Paris Air Show this past June.