Electric Aircraft: The Future of Short-Haul

Battery Technology: The Core Challenge

Electric flight is fundamentally constrained by energy density. Today's best lithium-ion batteries store approximately 250–300 Wh/kg. Jet fuel stores approximately 12,000 Wh/kg — about 50× more energy per kilogram. Even accounting for the superior efficiency of electric motors (~95%) versus jet engines (~45%), the effective energy advantage of jet fuel remains roughly 20–25×.

This means a battery pack capable of powering an aircraft for 500 km would weigh roughly 10× more than the equivalent jet fuel load. At that weight, there is little payload capacity left for passengers or cargo. The fundamental physics of battery energy density — not manufacturing cost or engineering design — is the limiting factor.

Solid-state batteries, which replace the liquid electrolyte with a solid conductor, promise 400–500 Wh/kg and better thermal stability. Companies like QuantumScape, Solid Power, and Toyota are targeting commercialisation by 2028–2030. Even solid-state batteries remain well below the 2,000+ Wh/kg needed for long-haul aviation, making battery-only electric commercially viable only for very short regional routes in the near term.

Current Projects

Several electric aircraft programmes are in advanced development or early commercial service:

• Heart Aerospace ES-30: 30-passenger hybrid-electric; pure electric for first 200 km, hybrid for up to 400 km; targeting certification 2028; backed by United Airlines and Air Canada
• Eviation Alice: 9-passenger all-electric commuter; first flight completed November 2022; targeting range of 440 km; DHL has placed orders for cargo variant
• Zunum Aero: Hybrid-electric regional (12 seats); backed by Boeing HorizonX; development on pause pending investor clarity
• Pipistrel Velis Electro: 2-seat trainer; the first type-certified electric aircraft (EASA, 2020); in service at flight schools across Europe

Range Limitations

Current all-electric aircraft are commercially viable for routes under 300 km. At 400–800 km (the most common European short-haul range), only hybrid-electric designs with a fuel-burning range extender are competitive. Over 800 km, electric propulsion is not currently viable for commercial transport without a step-change in battery energy density.

The routes that make sense today are thin regional routes where small aircraft (9–20 seats) operate, typically in Scandinavia, coastal US commuter operations, and island-hopping networks. Airlines like Norwegian, Wideroe, and Cape Air have expressed strong interest for their 100–300 km routes.

Hybrid-Electric

Hybrid-electric architectures use electric motors for high-power phases (takeoff and climb) where thermal engines are least efficient, then switch to conventional fuel-burning engines for cruise. Benefits include peak power reduction (smaller, lighter engines), regenerative descent capture, and operational flexibility.

The Heart Aerospace ES-30 design uses 30 kWh batteries for zero-emission operation near airports (important for noise and air quality) with turbogenerators for longer cruise segments. ATR is exploring hybrid modifications to the ATR 72 platform that could reduce fuel consumption 20–30% on short sectors.

Timeline

• 2025–2028: Certification of 9–19 seat electric/hybrid-electric aircraft; thin regional routes in Europe and North America
• 2030–2035: Solid-state batteries enabling 30-seat all-electric at 400 km range; hybrid-electric narrowbodies entering development
• 2035–2040: 50–100 seat hybrid-electric aircraft for routes under 1,000 km; incremental SAF/electric blending on short-haul
• 2040+: All-electric narrowbody possible only with 1,000+ Wh/kg battery technology, not currently on roadmaps

Airlines Leading Interest

United Airlines has invested directly in Heart Aerospace and Archer Aviation (eVTOL). Air New Zealand ordered Heart Aerospace ES-30 aircraft for domestic New Zealand routes. SAS and Wideroe are piloting electric routes in Norway where short fjord crossings are commercially viable at small scale. In the UK, the Hybrid Air Vehicles Airlander 10 (helium-assisted hybrid-electric) has taken orders from airlines targeting lower-speed scenic routes.