Passengers with a low-cost airline could be served water created as a waste product from hydrogen batteries under plans for a zero-emissions fuel system.

Budget airline easyJet made the claim as it unveiled designs for a hybrid plane that could be trialled later this year.

The concept would involve storing a hydrogen fuel cell in the aircraft’s hold.

Energy captured as the brakes are deployed during landing would then power the jet when it is on the ground, similar to the kinetic energy recovery system used in Formula One.

Ian Davies, easyJet’s head of engineering, said the water produced as a waste product from the batteries would be discarded or reused.

Asked whether it would be served to passengers, he replied: “I think we could reuse the water. It’s absolutely pure. Why would we throw water away when it’s absolutely pure?”

He said it could be used for drinking and flushing toilets, adding: “This is potentially the freshest, cleanest water.”

EasyJet estimates that around four per cent of its fuel consumption is used when its aircraft are taxiing.

The airline hopes hybrid planes could save 50,000 tonnes of fuel for its fleet each year.