RE:RE:Co2 calculator page down CNG can also be substituted with renewable natural gas (RNG) with an emisison score lower than electric. Fuel savings can be north of 50% with 100% emission reduction. Many large fleets are adopting RNG in mass including: Amazon, Waste Management, UPS and many more.
https://esgreview.net/2023/01/04/wm-invests-us825-million-toward-100-rng-fueled-natural-gas-fleet/
https://www.truckinginfo.com/10156121/amazon-order-drives-renewable-natural-gas-development
https://www.freightwaves.com/news/ups-is-converting-ground-fleets-to-renewable-natural-gas