There are a couple of options to choose from, although they will not provide extra power for takeoff. I’m not aware of any systems designed for larger aircraft than the B737 and A320.
They may save fuel during taxi, but the extra weight will cause an increase in fuel burn during flight.
The airlines will ultimately decide if these are worth the extra weight and maintenance to warrant the fuel savings they report to have.
An Electric Green Taxiing System (EGTS) is an electric taxiing system which allows aircraft to taxi and pushback without requiring the use of aircraft engines, and is designed to reduce fuel volumes used by aircraft and reduce greenhouse gas emissions during ground operations. EGTS technology enables aircraft to avoid using their main engines during taxiing and instead taxi autonomously under their own electrical power, using the Auxiliary Power Unit (APU) generator. The system is designed for single-aisle aircraft, such as the Airbus A320 and the Boeing 737.
Safran Honeywell EGTS installed on an Airbus A320
Stirling Dynamics has contracted with WheelTug to design a new nose wheel for Boeing’s 737NG jet airliner. The new wheel will contain electric motors powered by the aircraft’s Auxiliary Power Unit (APU) that will allow the pilot to back away from or taxi to an airport gate without using engine thrust or a ground tug vehicle.
WheelTug allows an aircraft to taxi without using engines or a ground tugStirling Dynamics
Source: Quora
