If it's being burned at the energy plant, electric is worse.

so long as you applying your open flame to metal is more efficient than a natural gas plant is at converting it to electricity and an induction is and applying that to your cookware. I'd be curious to see the numbers there... but if I were a betting I'd think induction would be better.

Energy plants are only going to get greener from now on, and are pretty green depending on the location ( GP mentioned California).