Carbon‐neutral pathways to 2050 for Japan's aviation industry in the absence of a mass supply of sustainable aviation fuels

The global aviation sector must reduce its carbon dioxide (CO2) emissions to achieve its 2050 net‐zero emissions target. Although the current pathway to the target considers an increase in aviation demand following the COVID‐19 pandemic, emissions can be offset by the introduction of future technologies such as electric and hydrogen aircraft and sustainable aviation fuels (SAF). However, the commercialization of these future technologies is uncertain. In this study, we explore the feasible pathways for achieving the 2050 target in Japan. Specifically, we compare non‐future technology pathways, such as improving fuel efficiency and controlling flight distance and aircraft lifespan, with future technology pathways, such as introducing SAF. The results showed that the non‐future technology pathway would require up to 27% suppression of cumulative flight distances by 2050 relative to the predicted flight distance if only improving fuel efficiency and controlling flight distance and aircraft lifetimes. Minimizing the cumulative cost of the target achievement is contingent upon maximizing fuel efficiency and aircraft life extension. Additionally, the target achievement requires switching domestic flights to railway transport and limiting international flights for leisure, as well as increasing fares by up to 48% to compensate for sale declines. If future technologies are not fully implemented, substantial social change will be required to achieve the target.