Aviation's best bet for cutting emissions is a new kind of fuel — but there's nowhere near enough of it

• The US accounts for 25% of global aircraft emissions.
• Sustainable aviation fuel can be up to 80% less carbon intensive than conventional jet fuel.
• The US wants 3 billion gallons of sustainable aviation fuel by 2030. Today, it produces a fraction.

Of all global aircraft emissions, the US accounts for 25%. There's a goal to reduce that to zero by 2050, but it won't be easy.