Cars aren’t the only polluters. If we want to save the planet, every part of how we travel has to change, and that includes . Whether or not that method of clean travel will catch on though is another thing. But as reports, United Airlines thinks electric planes will be the next generation of air travel, but mainly for short, regional flights.

One of the main reasons United is hoping electric planes catch on is a recent deal the company has entered into. It has a contract to buy electric planes from a startup called . The Swedish startup is developing an eVTOL called the ES-19 for local flights.

United’s idea is that people living in small cities or areas who drive on trips that are 250 miles or less to take a plane. Anders Forslund, CEO of Heart agrees, saying flying needs to go back to how it was in the 1990s when there were a lot of small, regional airports that people could fly into. “Go back to the 1990s, there were hundreds of small aircraft serving a lot of communities that have now lost service,” he said. But most of those regional flights stopped because air travel got so expensive.

Ultimately though United is hoping for these electric planes to reach a cost parity or be cheaper than traditional air travel. United sees this happening within a decade.

United is just one of a few airlines that have recently begun to invest in eVTOL aircraft as the next big thing. recently invested $60 million into an eVTOL startup. But so far they aren’t shaping up to be much of anything. Testing these things has been a challenge as a lot of startups on test flights.