Airbus’s embrace of more-electric system architectures hasn’t yet manifested itself in such visible examples as less dependence on hydraulics and bleed-air. In this respect, the European airframer appears to be behind the more-electric achievements seen in its rival Boeing's 787 Dreamliner, but Airbus sees still wider application of the technology emerging in its own products soon.

Speaking at the More-Electric Aircraft 2015 conference in Toulouse earlier this month, Airbus executive vice president for engineering Charles Champion expressed high expectations for the electric taxiing system (EGTS) under development by Safran and Honeywell, for example. “The fuel burn benefit could be three percent on a typical A320 sector,” he said. The program has progressed into the production phase and Airbus has started offering it to customers. “Maturation takes time and we have to demonstrate customers they can use it every day,” he added.

Opposing views emerged on whether the APU’s role should expand by using it in flight instead of the current practice of shutting it down. Microturbo, a Safran company that has designed an APU for more-electric business aircraft and helicopters, argued using it in flight would optimize engine load management. But Collins Smith, Rolls-Royce's director of engineering and technology, raised the possibility of simply removing the APU thanks to engine redundancy.

A low-pressure generator on the fan could replace the ram air turbine (RAT), according to Smith. Etienne Foch, Airbus’s head of electric network research, suggested a fuel cell could replace both the APU and the RAT. Among the remaining issues, he noted the need to employ a bulky reformer to produce hydrogen on board or liquid hydrogen, which involves complex cooling system and logistics.

Zodiac Aerospace is conducting a research and development project, dubbed Hycarus, that involves testing a fuel cell in flight on a Dassault Falcon business jet next year. Placed under high pressure, the hydrogen will take a gaseous form. The equipment manufacturer hopes to offer a product shortly after the end of the three-year project, in 2016.

The application could power non-essential equipment on a commercial airliner, such as the galley and lavatory, said Julien d'Albigny, Zodiac’s fuel cell product engineer. A fuel cell’s main benefit over an APU lies in the fact that the former emits neither carbon dioxide nor nitrous oxide.