The head of the world's second-largest airline has warned that measures to fight climate change will make air travel more expensive.
"Over time, it's going to cost us all more, but it's the right approach to take,"
Aviation is responsible for about 2.5% of the carbon emissions that are warming the planet, according to the International Energy Agency.
Critics argue that the best way to reduce them is by flying less.
Atlanta-based Delta says that after spending $ 30 million a year to offset the carbon it produces, it has since March 2020 managed to neutralize its emissions.
It has also pledged to spend US $ 1 billion over the next decade to cancel all the emissions it generates.
More fuel-efficient aircraft, sustainable aviation fuels, and removing carbon from the atmosphere are some of the ways he hopes to achieve this.
Andreas Schafer, professor of energy and transport at University College London, said that "it will cost trillions rather than billions of dollars" to move the global aviation sector to net zero carbon emissions.
Preliminary results of an investigation by his team suggest that airfares should increase by 10-20% to cover costs.
"In the short term, government support will be needed, as decarbonizing aviation will be a great challenge and current efforts will need to be dramatically expanded," explains Professor Schafer.
Bastian admits that it is an ambitious goal that his airline will not be able to achieve on its own.
"It's the biggest long-term challenge facing this industry," he said. "We are in an industry classified as difficult to decarbonize because we do not yet have biofuels or sustainable aviation fuels (SAF) en masse that we are going to need."
Delta aims to use 10% sustainable aviation fuel by the end of 2030.
Many airlines and fuel companies are investing in SAF. Other technologies being developed involve turning food waste into jet fuel and using carbon dioxide extracted from the air.
However, these still cost more than traditional fuels and the quantities required are also considered problematic.
