carbon-free

From carbon +‎ -free.

carbon-free (not comparable)

1. Not containing carbon.
2. Not producing any carbon compounds such as carbon dioxide that might contribute to pollution, including to the atmosphere.
   • 2021 January 27, Richard Clinnick, “Rail Operations orders UK's first Class 93 tri-mode locomotives”, in RAIL, issue 923, page 10:

     The two LTO battery packs provide 400kW (536hp) extra power to supplement the engine when the locomotive is running in diesel/battery hybrid mode, as well as last-mile carbon-free shunting operation.

• “carbon-free”, in Lexico, Dictionary.com; Oxford University Press, 2019–2022.