Liquid H2's key drawcard to aircraft designers is its impressive energy density by weight, but Airbus believes there are serious opportunities to be explored in another of its properties: temperature. To keep it liquid, it needs to be stored cryogenically at -253.15 °C (-423.7 °F), and Airbus figures that if you've got a monster cold source like that on board your aircraft, you might as well make use of it.

The theory is that the liquid hydrogen can supercool the entire electric powertrain down to superconducting temperatures, at which point resistance virtually disappears from the system, and efficiency skyrockets. A powertrain designed to take full advantage of this effect, reasons Airbus, could get the same job done at less than half the weight, half the electrical losses and reduced voltages.