It would have no effect at home.
On the road some chargers are priced by max theoretical speed. 150 vs 350 with 150 being cheaper by the KWH.
Ive also seen variable rates on the same charger but that seems to have gone by the wayside.
Quit often the car wont be able to take the max rate anyway if charging begins above X % SOC.
The Ultium cars showed this massive dip early on.
I dont know what the latest is on them all, this curve would suggest that if you pull into a charger at 50% or greater SOC you might as well use the lower rate charger IF its cheaper because the car wouldn't take anything above 150 anyway.
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