What are the main challenges to using electric propulsion in commercial aviation?
Graham Warwick, Aviation Week’s Executive Editor, Technology, and France Bureau Chief Thierry Dubois team up to answer:
Challenges to the use of electric propulsion in commercial aviation are many and range from the batteries and motors to the wiring and cooling. But from the beginnings in automotive technology, progress is taking place in tailoring electric drive trains to aerospace applications.
The biggest challenge is the low energy density of batteries. Jet fuel has an energy density of about 12,000 Wh/kg whereas commercially available lithium-ion batteries have an energy density at the cell level of about 250 Wh/kg. Energy density at the pack level, including the weight penalty for thermal-runaway containment and other safety features, is typically 20% lower.
Although that might seem an impossible gap to bridge, electric-propulsion pioneers believe that they can develop commercially viable small, short-range aircraft using available batteries. “Small” refers to aircraft with up to 19 seats, and “short-range” pertains to distances less than 250 mi.—enough range for many regional routes, the pioneers argue.