Despite slackening growth in 2017-2018, demand for air transport is expected to remain strong in the future. Meanwhile, impressive efficiency improvements achieved since 2000 also show signs of slowing down.

Aviation Jpg

Key findings

Direct CO2 emissions from aviation in the Net Zero Scenario, 2000-2030


Global aviation emissions increased as countries emerged from Covid-19 lockdowns

In 2021 aviation accounted for over 2% of global energy-related CO2 emissions, having grown faster in recent decades than road, rail or shipping. As countries emerged from Covid-19 lockdowns, aviation emissions in 2021 reached around 720 Mt, regaining nearly one-third of the drop from 2019 levels seen in 2020. Many technical measures related to low-carbon fuels, improvements in aircraft and engines, operational optimisation and demand restraint solutions are needed to get on track with the Net Zero Emissions by 2050 Scenario – to curb growth in emissions and ultimately reduce them this decade.

Important recent policy developments that could help towards this end include the US Sustainable Aviation Fuel Grand Challenge announced in September 2022, which includes funding to demonstrate fuel and aircraft technologies, and the proposed ReFuelEU Aviation regulation, which is currently under development and if adopted will set blending mandates for sustainable aviation fuels.

Energy intensity of domestic and international commercial passenger aviation in the Net Zero Scenario, 2000-2030


Activity growth outpaces fuel efficiency improvements, and progress has slowed

New aircraft are up to 20% more efficient than the models they replace, but this has been insufficient to keep up with growing activity. Between 2000 and 2010 fuel efficiency improved by 2.4% per annum, and by 1.9% from 2010 to 2019, demonstrating that additional incremental improvements are becoming more difficult.

Meanwhile passenger demand grew at over 5% per year from 2000 to 2019, meaning that annual improvements are far below what is needed to align with the Net Zero Scenario.