EV Range Added per Hour of Charging
How many miles of driving range an hour of charging adds -- the number that sizes an EVSE to a commute or a fleet's daily miles. Range per hour = EVSE power (kW) x charge efficiency x the vehicle's efficiency (mi/kWh): the kilowatts delivered, after the ~10-15% AC losses, times how far the car goes per kWh. A 7.7 kW Level 2 charger at 88% on a car getting 3.5 mi/kWh adds ~23.7 mi of range per hour, so a 100-mile commute replenishes in ~4.2 hr, comfortably overnight. A 9.6 kW circuit adds range proportionally faster, but the vehicle's ONBOARD charger caps the AC rate (see ev-charge-time), and a less efficient vehicle (truck / cold weather) adds fewer miles/hr. A steady AC Level 2 estimate; DC fast charging tapers, and the onboard-charger limit and actual efficiency govern.
Formula and source
range_added_mi_per_hr = evse_power_kw x charge_efficiency x vehicle_efficiency_mi_per_kwh; hours_to_add_target = target_range_mi / range_added_mi_per_hr.
EV range-added-per-hour of AC Level 2 charging (energy identity; SAE J1772 onboard-charger limit), by name; the vehicle's onboard charger and actual efficiency govern.
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