Flying sustainable : the role of electric aircraft in decreasing the CO2 emissions
According to the International Air Transport Association (IATA), in 2020, global annual international aviation emissions are already around 70% higher than in 2005. The International Civil Aviation Organization (ICAO) forecasts that in the absence of additional measures by 2050 they could grow by over further 300 %. (1)
In order to slow down this negative trend, the aviation industry has committed to reducing its CO2 emissions in 2050 (2) by half compared to those of 2005. One of the most notable initiatives on the way to achieve this goal is to substitute jet fuel with electrical power. (3) It can be observed from a consistent increase in the electrification of aircraft systems, research on electrical propulsion, and investments in electric or hybrid or turboelectric aircraft designs.
Technology development for electric aircraft is also broadly supported by the aviation industry’s biggest players (Boeing and Airbus) and their suppliers, such as Siemens, Rolls Royce and Safran. Altogether, as of July 2020, there are around 28 different electric and 6 hybrid aircraft projects in the world. (4) Some recent announcements were made by two UK companies – Faradair, expecting to fly their Bio Electric Hybrid Aircraft (BEHA) by late 2023 or early 2024 and Electric Aviation Group (EAG), presenting plans for a 70-seat hybrid-electric regional airliner, ready to enter service in 2028. (5)
The electric propulsion besides being able to significantly lower carbon emissions/aircraft noise contributes to the development of new aircraft configurations. Powering such an aircraft, however, requires energy levels of tens of megawatts and hundreds of thousands of kilowatt-hours per flight. (6) The energy needed is supposed to be generated by the lithium-ion batteries installed onboard.
Would this switch be enough to achieve our sustainability goals?
According to the calculations made by Dunkan Walker, the world’s largest passenger plane, the Airbus A380, can fly 600 passengers over a distance of 15,000 kilometres, in a single flight. With current electric batteries, it could only fly a little over 1,000 kilometres. ‘To keep its current range’, continues Walker, ‘the plane would need batteries weighing 30 times more than its current fuel intake, meaning it would never get off the ground. Jet fuel still contains around 30 times more energy per kilogram than the most advanced lithium-ion battery currently available’. (7) Only small, short-distance aircraft can be 100% electrified today.
With the growth of the world population, expected to reach 9.7 billion in 2050, (8) the question of sustainable flight will become more and more critical. The aircraft electrification, while contributing to reducing the CO2 levels, is insufficient as a sole measure. On a global scale, this solution should be complemented with other actions – bettering aircraft efficiency, using sustainable aviation fuels (biomass, recycled oils, coal, ethanol) and setting more efficient flight paths.
P.S. You can estimate the emissions attributed to your air travel, by using the ICAO Carbon Emissions Calculator available here: https://www.icao.int/environmental-protection/Carbonoffset/Pages/default.aspx
- Reducing emissions from aviation, https://ec.europa.eu/clima/policies/transport/aviation_en
- Airlines vow to halve carbon emissions by 2050, https://www.theguardian.com/environment/2009/sep/21/airlines-carbon-emissions-cut
- Electric, Hybrid, and Hydrogen Aircraft – State of Play, ICAO Environmental Report 2019, p. 124
- Electric and Hybrid Aircraft Platform for Innovation (E-HAPI), https://www.icao.int/environmental-protection/Pages/electric-aircraft.aspx
- Alan H. Epstein and Steven M. O’Flarity, Considerations for Reducing Aviation’s CO2 with Aircraft Electric Propulsion, Journal Of Propulsion And Power Vol. 35, No. 3, May–June 2019