What do we talk about when we talk about electric propulsion in aviation?

Let’s talk about what is aviation electric propulsion?

Simply put, aviation electric propulsion technology converts electrical energy into kinetic energy to drive the aircraft to move. It uses a fuel-driven aviation gas turbine generator in conjunction with a battery pack to generate or store electrical energy, and converts electrical energy into shaft power through different coupling methods between the turbine and the motor, thereby driving a fan or distributed fan to generate the power required by the aircraft.

Let’s talk about why we need to develop aviation electric propulsion technology?

Electric propulsion technology has the potential to make our journeys cleaner, cheaper and more comfortable.

The aviation industry has always been a major carbon emitter in the global industry. According to data from EDGAR (Emissions Database for Global Atmospheric Research), in 2020, the amount of carbon dioxide emitted by the international aviation industry from the combustion of fossil fuels accounted for about 1% of the global total emissions. Aviation electric propulsion technology can emit less or even no carbon dioxide by adopting clean energy such as hydrogen, wind, and light energy, thereby effectively reducing the impact on the environment. It is one of the main power solutions for the aviation industry to achieve the goal of net zero emissions. In addition, since the cost of obtaining electricity can be very low or even zero cost, and the electric propulsion system is relatively easy to maintain, flying becomes more economical. Finally, in the process of converting electrical energy into kinetic energy, less noise is generated, which greatly improves the comfort of the journey.

Given so many benefits, why haven't we seen electric-propulsion aircraft in our daily lives?

Electric aircraft built with current technology are simply too heavy, and require extra weight and energy to cool the working parts, making them very inefficient. All aspects of the field of electric propulsion in aviation, including technologies such as motors, converters, circuit breakers, batteries, and cooling systems, still face some major challenges waiting to be overcome to keep components cool and minimize weight and heat losses.

Let’s talk about what achievements have been made in aviation electric propulsion technology so far?

In February 2024, Fengfei Aviation Technology Company used the pure electric 5-seater eVTOL aircraft Shengshilong to complete the flight from Shenzhen Shekou Cruise Home Port to Zhuhai Jiuzhou Port Terminal, shortening the one-way 2.5 to 3 hours of ground driving to 20 minutes. The aircraft is 11.6 meters long, with a wingspan of 14.5 meters, equipped with 13 propellers, a maximum take-off weight of 2,000 kg, a maximum payload of 350 kg, a maximum range of 250 kilometers, a maximum cruising speed of 200 kilometers per hour, and a passenger capacity of 4 seats + 1 pilot. This is the world's first public demonstration flight of a cross-sea and cross-city eVTOL electric vertical take-off and landing aircraft route, with a round-trip journey of more than 100 kilometers.

In March 2024, the full-scale prototype of Airbus's all-electric 4-seater eVTOL CityAirbus NextGen debuted at the Citybus test center in Donauwörth, Germany. It uses eight electric propellers as a distributed propulsion system, weighs 2 tons, has a wingspan of 12 meters, a speed of 120 kilometers per hour, and a range of 80 kilometers.

In addition, UAV engine manufacturer UAVHE released the 48kW hybrid electric propulsion system RW1-300C, Kite launched the 120kW KM-120 aviation electric motor, and UEC United Engine Manufacturing Group displayed a 500kW hybrid electric propulsion device verification machine at the 2023 Russian Industrial Exhibition. NASA, GE, Safran and many other scientific research institutions and international companies have also carried out a lot of research and experimental work in various key technical fields of aviation electric propulsion.

Although, due to the demanding power requirements of aviation flight, aviation electric propulsion technology still faces many challenges to overcome. However, the current research results have begun to show their edge and show great development potential. With the continuous deepening of technical research, practical aviation electric propulsion technology will become more and more mature, bringing revolutionary changes to our flight journey.