Despite slackening growth in 2017-2018, demand is expected to remain strong in the future. Meanwhile, impressive efficiency improvements achieved since 2000 also show signs of slowing down.
Better aircraft utilisation is one of the reasons for improved energy efficiency. The average number of passengers, and the average weight of cargo per flight, have both increased, lowering energy use per useful service delivered. Another driver of efficiency improvement is fleet renewal. The fuel intensity of new commercial jet aircraft fell 1.3% per year on average from 1968 to 2014, roughly doubling their efficiency.
Aviation energy efficiency needs to improve by more than 3% per year to 2040 to be in line with global climate goals. Some of the policy infrastructure to achieve this is in place. Under the Paris Agreement and various other frameworks, certain countries have set up targets for efficiency improvements in domestic aviation. The International Civil Aviation Organization (ICAO) has put in place policies to improve aircraft efficiency and limit the growth in CO2 emissions of international flights. Further policy measures, such as carbon pricing and even more stringent efficiency standards, would further help put aviation back on track.
Last updated Jun 16, 2020
Key findings
Evolution of aviation activity in selected countries in early 2020
Global aviation activity declined by a staggering amount in 2020...
As a consequence of global lockdown measures due to Covid-19 in early 2020, mobility – 57% of global oil demand – declined at an unprecedented scale. As lockdowns spread, global aviation activity had declined to a staggering 60% by the end of March 2020.
... but for years global aviation activity has been growing rapidly
Aviation emissions rose rapidly, at an average annual rate of 2.0% during 2000-19, with 5% average yearly rises in total commercial passenger flight activity since 2000. As most (>99.5%) aviation relies on jet kerosene, and as most jet kerosene (>85%) is used by commercial passenger aviation, the gap between these two metrics is largely explained by operational and technical efficiency measures adopted by commercial airlines, including new aircraft purchases. The energy intensity of commercial passenger aviation has decreased 2.8% per year on average, but improvements have slackened over time, and they must be maintained to limit fuel combustion to volumes at which SAFs – low-carbon alternatives to fossil-based jet kerosene – can power commercial aircraft. Near to mid-term priorities include implementing fiscal and regulatory measures that promote exploitation of operational and technical efficiency and managing the investment risks. These risks exist for developing and deploying clean sheet airframes, new engines and propulsion systems, and for production low-lifecycle GHG-emissions SAF.