EasyJet has unveiled plans for a zero-emission hydrogen fuel system for its aircraft which it claims could save around 50,000t of fuel per year, along with associated CO2 emissions.
The airline aims to reduce passengers' carbon footprint by 7% over the next five years compared to its emissions today, which are 81.05 grams CO2 per passenger kilometre.
The hybrid plane concept was inspired by students at Cranfield University, who were asked to develop ideas for what air travel might look like in twenty years’ time, as part of a competition to celebrate easyJet’s 20th birthday in November 2015.
The hybrid plane concept utilises a hydrogen fuel cell stowed in the aircraft's hold. This allows energy to be captured as the aircraft brakes on landing and is used to charge the system’s lightweight batteries when the aircraft is on the ground — much like the Kinetic Energy Recovery System (KERS) found in Formula 1 cars.
The energy can then be used by the aircraft – for example when taxiing - without needing to use their jet engines. Due to the high frequency and short sector lengths of easyJet’s operations, around 4% of the airline’s total fuel consumed annually is used when the airline’s aircraft are taxiing.
Each aircraft would have motors in their main wheels and electronics and system controllers would give pilots total control of the aircraft’s speed, direction and braking during taxi operations. The system would therefore reduce, if not remove altogether, the need for tugs to manoeuvre aircraft in and out of stands, delivering more efficient turnaround times and increased on time performance.
Other “green taxiing” concepts currently being explored include the Safran/Honeywell Electric Green Taxiing System (EGTS) and the Taxibot system proposed by Israel Aerospace Industries (IAI).