Referring to the example from the Twitter post you cited, wouldn't the KWh per mile simply be a lot higher because these vehicles are engaging in much less efficient travel overall? City driving itself is often pretty inefficient because of all the stopping and going, and these vehicles likely are driving in a lot of the rush hour traffic and high density areas everyday. Not to mention they probably idle around a lot more than a normal persons car would in a day.
So wouldn't that be the reason the figures would look 2.5x worse than the regular Jaguar? I'm sure there are other factors of course since running the computer systems, lidar and all the other features will also consume more power, so I'm sure from a baseline it will be less efficient anyway, I just think because of the kind of driving it engages in, this will make it also look far less efficient.
Depending on conditions, heat or AC can consume up to 5 or 6 kW in extreme weather and a small fraction of that in milder conditions. The most efficient speed of an EV is hard to pin down. If all fixed loads could be turned off, it would be most efficient at the slowest possible speed but with HVAC and compute loads present, the most efficient speed is around where the aerodynamic load is equal to the fixed load. That's still likely to be rather slow but the idealized math that gives this optimum is for steady-state operation. There is a round-trip loss for regen, so there is still an advantage to steady operation even if it is not as big as with ICE cars where no kinetic energy is recovered.
My guess for the poor reported number is excessive idle time w/ HVAC and compute stuff on within the trip interval.
1. My whole house AC only consumes 3 kW when the outside is really hot, like 36 degrees C, and I seriously doubt that car AC can consume 5 or 6 kW
2. With hotter weather, the density of air also decreases and air resistance is reduced. This partially offsets the need for extra cooling (of both the occupants and the battery), so range is only perhaps impacted by 5-10%.
Max power consumption of the compressor in my car is 5.5 kW (see pg. 28 of https://www.scribd.com/document/783343319/MEB-220169869). The blowers would draw additional power. These values would only be hit in extremes and I'm not certain the compressor can run at 100% duty cycle.
Possible, but EVs tend to be more efficient in city driving than highway driving, thanks to regenerative braking and the fact that the dominant form of energy loss, air resistance, scales quadratically with speed.
So wouldn't that be the reason the figures would look 2.5x worse than the regular Jaguar? I'm sure there are other factors of course since running the computer systems, lidar and all the other features will also consume more power, so I'm sure from a baseline it will be less efficient anyway, I just think because of the kind of driving it engages in, this will make it also look far less efficient.