June 16, 2026 · 5 min read
Most Level 2 charger installations that go sideways go sideways at the panel. The unit itself mounts in an hour. Whether your electrical service can feed it is the actual question.
Continuous load is the rule that matters
EV charging is a continuous load, which means the circuit has to be sized at 125% of the charger's draw. A charger pulling 40 amps needs a 50-amp circuit. One pulling 48 amps needs 60. This is why the breaker in your panel is always larger than the number on the charger.
Three things your panel must have
- Spare capacity in the load calculation, not just a free slot
- Two adjacent breaker spaces for a 240V double-pole breaker
- A busbar rating that can accept the added breaker without exceeding its limit
Charging speed, translated
A 32-amp charger adds roughly 20 to 25 miles of range per hour. A 40-amp charger adds around 25 to 30. A 48-amp charger adds more still, but only if your vehicle's onboard charger can accept it — many can't, and paying for the bigger circuit buys nothing today.
If the panel is full
A full panel is not automatically a service upgrade. Options in rough order of cost: reorganize existing circuits to free spaces, add a subpanel nearer the garage, install a load-management device that pauses charging during peak household demand, or upgrade the service.
Load management is underused and often the right answer. It lets a 100-amp service run a full-speed charger safely by simply not charging while the dryer and the oven are both going.
Hardwired or plug-in?
Hardwiring is required above 48 amps and is generally more reliable outdoors and in cold garages. A NEMA 14-50 receptacle is convenient if you may take the charger with you, but the receptacle itself becomes a wear point and should be a quality commercial-grade device.
Permits are not optional
A new 240-volt circuit requires a permit and inspection in every jurisdiction we serve. Unpermitted EV circuits show up at resale and during insurance claims, and they are not worth the few hundred dollars saved.
Want this answered for your panel?
A tech opens the panel, runs the load calculation and leaves you with a written price. No cost, no obligation.