Funny thing...my employer has invested heavily in EVs for our fleet, spanning from small cars like the Volts, through 1/2 ton pickups, and all the way up into heavier service trucks such as bucket trucks. I remember we got a handful of full EV Silverados about 5 years ago, while the bigger trucks are more along the lines of hybrids, where the main propulsion of the trucks are still diesel with a large battery bank to run the hydraulics, PTO sections for the booms and to run the APU for air conditioning. This way we don't have those trucks sitting at a high idle for hours at a time with the guys sitting in the bucket, or in the cab running the AC while doing computer work. With temps often exceeding 100*F in the summer here, most of our vehicles get started in the morning, and don't get shut down until the work day is over. For many of the field service guys, that's 12+ hours a day.
Although they've been dabbling in EVs for decades at this point, they started getting more serious about it roughly 10 years ago.
All the reports I've seen thus far is that the EVs have been costing us considerably more overall. While yes, we're saving money on fuel, the downtime, maintenance, and repair of these vehicles have FAR outstripped any fuel cost savings we've seen.