Electric Energy Carriers in More Electric Aircraft: Suitability Assessment, Potential Use Case Definition, System Sizing and Fuel Penalty Estimation

The transition toward electrified aviation is driven by the need to reduce the environmental impact of air transport. This study evaluates the suitability of electrical energy storage systems (EESSs), including batteries, flywheels, and supercapacitors, for powering aircraft subsystems in more electric aircraft (MEA). A multi-criteria assessment considering performance, integration, safety, and sustainability identifies supercapacitors as the most suitable option for short-duration applications, batteries for long-duration applications, and both technologies as similarly suitable for medium-duration operations. Flywheels are found to have limited applicability due to safety concerns and integration challenges. A system sizing for representative use cases indicates that fuel-saving potential is highly dependent on the specific energy of the EESS. For a 1500 km mission, a battery system with a specific energy of 0.5 kWh/kg could reduce subsystem fuel consumption by approximately 30% relative to conventional operation, with the reduction increasing to around 70% at 1.0 kWh/kg. Overall, the findings highlight the significant potential of EESSs for next-generation aircraft, provided that continued advancements in energy density and system integration can be achieved.