Citing the limitations of current and foreseeable battery technology, Tecnam announced it has put development of a twin-engine electric commuter aircraft on hold until batteries of sufficient power and life-cycle endurance become available.
The Italian airframer, which recently celebrated 75 years of designing and building airplanes, spent three years working on its largest all-electric aircraft to date before deciding its time has not yet come. The P-Volt, announced in 2020, sought to adapt the P2012 Traveller (now flying for launch customer Cape Air) for electric airline service.
“Tecnam has a deep understanding of electric flight, gained from previous projects such as the H3ps hybrid aircraft based on the P2010 four-seater, and today we have looked closely at the state of the art in energy storage and realistic 5 year developments, excluding technological revolutions that no one can speculate on,” the company wrote June 13. “One of the conclusions was that an aircraft with a battery pack at the end of its life would not be the best product for the market, but certainly the worst in terms of Net Present Value (NPV).”
Specifically, Tecnam cited the life-cycle limits of current batteries:
“Taking into account the most optimistic projections of slow charge cycles and the possible limitation of the maximum charge level per cycle, the real storage capacity would fall below 170Wh/kg, and only a few hundred flights would drive operators to replace the entire storage unit, with a dramatic increase in direct operating costs due to the reserves for battery replacement prices.”
Tecnam’s skepticism contrasts with the optimism investors have expressed by funding a number of electric aviation projects, though others have drawn similar conclusions, including pilot and physics professor Peter Rez, who has written extensively about the limitations of battery and hydrogen-powered propulsion in aviation. Rez noted in 2018 that the best available batteries fall far short of matching the energy density of gasoline or kerosene. In the context of eVTOL aircraft, he compared a small electric air taxi to a Robinson R44 helicopter:
“Replacing the fuel with a battery would reduce the time for a journey to 10 min before a recharging is necessary,” Rez wrote at the time. “If more of the mass were devoted to fuel or battery then there would be less available for passengers (it is already a tight squeeze). The poor energy density of batteries compared to liquid hydrocarbons limits both the journey time and the range of an electrically powered helicopter or drone. Furthermore, as with the electric car, more time will be spent on charging the battery than actually making a journey.”
Batteries have not improved dramatically since, and many eVTOL designs include a fixed-wing element to extend range. Rez more recently cast a skeptical eye on hydrogen fuel options, which face different limitations but, in the view of Rez and fellow skeptics, the same or similar net result.
Tecnam’s senior research and development officer Fabio Russo said the company does not feel compelled to join “any Electric Rush,” and continued, “It has always been our culture to commit to achievable goals with customers and operators, and we intend to keep that promise. We hope that new technologies will make businesses viable sooner rather than later, and we have real confidence in our partners' ability to bring highly valuable products to the zero-emission powertrain and energy storage arena.”