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The United Airlines Ventures Sustainable Flight Fund is a winner in Fast Company’s 2024 World Changing Ideas Awards. Right now, sustainable aviation fuel, or alternative jet fuel made from nonfossil sources, powers less than 0.1% of planes in the U. S. That’s both because there’s so little of it available and because it’s expensive.

Google’s work using AI to reduce contrails is a winner in Fast Company’s 2024 World Changing Ideas Awards. The thin clouds that streak behind airplanes, called contrails, are a sizable source of global warming, responsible for more than a third of aviation’s climate impact. But slightly changing a plane’s flight path can help avoid the phenomenon, which happens when hot exhaust mixes with cold, humid air.

Plug Inn, from Renault and Publicis Sapient, is a winner in Fast Company’s 2024 World Changing Ideas Awards. In the tiny French village of Guessling-Heméring, there aren’t any public EV chargers. But if you’re driving an electric car through the area, you can use an app to book time with a private charger at someone’s home.

For its work on using AI to address climate change, Google is Fast Company’s 2024 World Changing Company of the Year. As the use of artificial intelligence grows, there’s a risk that it could boost emissions as it drives up demand for energy at data centers. But AI also has the potential to help find new ways to shrink humanity’s giant carbon footprint.

TurtleTree’s animal-free lactoferrin is a winner in Fast Company’s 2024 World Changing Ideas Awards. Fengru Lin, cofounder and CEO of Singapore biotech company TurtleTree, wants to find a more sustainable way to make milk. But she knows that lab-grown milks can’t compete with cow’s milk when it comes to price (at least not yet).

The Global Gateway Program, from Automation Anywhere and Robo Co-Op, is a winner in Fast Company’s 2024 World Changing Ideas Awards. Around the world, there are more than 100 million refugees who were forced to flee their homes because of violence, persecution, climate change, and more. Being displaced comes with a slew of challenges, of course, like finding work—made even more difficult by a language barrier or a mismatch in employment skills.