gnuarm
Model X 100 with 72 amp chargers
I almost never charge my EVs at full power for just this reason. I can get away with less than half power, which is what I do. For me there is no reason to stress the wiring and HPWC until I actually need to do so which is almost never.
As an extra step of redundancy, when I had the HPWC installed I also had my electrician install a 14-50 in the same spot. With the 14-50, I could use my UMC to charge the car too.
I don't mean to make light of people's concerns, but "stress the wiring and HPWC"??? The wiring could not care less what current you run through it. Unless the car is less efficient at higher currents the wire doesn't waste any more energy at high currents than low. The HPWC should be designed to take the full current it is rated for and should not wear any more at higher currents.
If the devices are not designed correctly or are not installed correctly, there can be problems at high currents. Otherwise it is good to go without concern. These are not mechanical devices which wear faster than proportionally when pushed hard. Even the relay in the HPWC is not impacted by the current since it only opens or closes when there is no current flowing. When statically closed the relay does not appreciably wear from the current flowing.
I'm not clear on how many circuits you can install in a panel. Is there any limit other than the mechanical issues? I already have a 60 amp breaker for the heat pump with electric backup, a 30 amp for the hot water heater, something for the stove, a 30 amp for the well, a 50 amp for the hot tub and maybe some others. If I add a 90 amp for an HPWC (or maybe 100 amp so I can have two at some point) as well as another 50 for a 14-50 outlet, will that be too much on a 200 amp service??? Can you branch off a 50 amp outlet from the 100 amp circuit if you use a 50 amp breaker in a box by the outlet? Would this require any sort of a switch to prevent the HPWC from being used at the same time?