> Once, after Mr. Puglia had driven 35 miles to an ice rink, his range fell by 73 miles. Another time, a 60-mile jaunt reduced his range by 110 miles.

I've found that the range estimate in my Ford CMAX (PHEV) is highly sensitive to recent driving conditions. For example, I drive one-pedal and am more conscientious about regeneration than my wife. When I drive the car after having been the last driver, the estimate is perhaps 20% greater than if I drive after she drove it.

The result is that the range can drop by a lot even with relatively short trips. In some ways this is bad — it would be better if the vehicle showed accurate range estimates from the time you turn it on. This could be optimized by taking temperature into account more aggressively (I imagine Ford already accounts for it to some extent). But in other ways, there's no way for a vehicle to know if you're going to be heading uphill or downhill on your next trip, or if you're taking the freeway or city streets. It sucks when range estimate swing wildly, but it's possible that this is better than the alternative — that it remains too rosy for too long, and then you're screwed.