The short answer
From the 2024 model year the Hummer EV carries a 19.2 kW / 80 A onboard charger, replacing the earlier 11.5 kW unit. Using it fully needs a 100 A circuit — half a 200 A service — which almost no house can spare. Install 48 A on a 60 A breaker, which is the fastest charge a normal residential service can deliver, and expect to use it for a long time: at 65.1 kWh per 100 miles this is the least efficient vehicle we cover.
The Hummer EV is where every tension in home charging advice comes to a head. The vehicle genuinely benefits from more power than any other we cover. The electrical reality is that most houses cannot provide it. Both of those things are true at once.
The constraint: what this car accepts
Everything else on this page follows from one number. The GMC Hummer EV's onboard charger accepts a maximum of 19.2 kW, which is 80 amps at 240 volts. No wall charger can exceed it, and a charger rated above it delivers no extra speed.
| Specification | Value | Source |
|---|---|---|
| Maximum AC power accepted | 19.2 kW | 2024+ Hummer EV 19.2 kW onboard charger |
| Maximum AC current at 240 V | 80 A | 2024+ Hummer EV 19.2 kW onboard charger |
| Connector | J1772 | GMC Hummer EV information |
| EPA range (2025 Hummer EV Pickup 3X) | 312 mi | US DOE / EPA fueleconomy.gov |
| EPA efficiency | 65.1 kWh / 100 mi (52 MPGe) | US DOE / EPA fueleconomy.gov |
| EPA published 240 V charge time | 11.2 hours | US DOE / EPA fueleconomy.gov |
The consequence: the circuit you actually need
Take the car's 80 A ceiling and work backwards. NEC 625.42 classifies EV charging as a continuous load, and NEC 625.41 requires overcurrent protection at not less than 125% of the maximum load — so a 80 A charger needs a 100 A two-pole breaker and 3 AWG copper at the 75 degC column of NEC Table 310.16.
| Item | This car | Why |
|---|---|---|
| Charger output | 80 A | Matches the car's 80 A ceiling exactly |
| Power delivered | 19.2 kW | The lower of the charger's output and the car's limit |
| Breaker | 100 A, two-pole | NEC 625.41 — 125% of a continuous load |
| Copper conductor (conduit, 75 degC) | 3 AWG | NEC Table 310.16 |
| A bigger charger would | deliver nothing extra — this is already the car's ceiling | The lower of the two numbers always wins |
Charge times, with the arithmetic shown
EPA rates the 2025 Hummer EV Pickup 3X at 65.1 kWh per 100 miles. That single figure lets you calculate any charge time you like, and it is why we show the formula rather than asserting a number.
hours = (miles x 65.1 / 100) / (kW x 0.9)
At 19.2 kW, this car gains about 27 miles of range per hour
The 0.9 allows for AC-to-DC conversion losses in the onboard charger — roughly 10% of what your meter records never reaches the battery. EPA efficiency figure from the US DOE / EPA fueleconomy.gov service, 2025 Hummer EV Pickup 3X, queried 2026-10-05.
| Charger | Miles added per hour | Hours to add 100 miles |
|---|---|---|
| 16 A (3.8 kW) | 5 | 19h 02m |
| 24 A (5.8 kW) | 8 | 12h 28m |
| 32 A (7.7 kW) | 11 | 9h 24m |
| 40 A (9.6 kW) | 13 | 7h 32m |
| 48 A (11.5 kW) | 16 | 6h 17m |
| 80 A (19.2 kW) | 27 | 3h 46m |
For context, EPA's own published figure for a full charge at 240 V on this trim is 11.2 hours.
What to buy for a GMC Hummer EV
Our picks for the GMC Hummer EV
Both are matched to this car's 80 A ceiling. The top pick is most households, and anyone with a tight panel; the alternative is there because a house with rooftop solar.
Most households, and anyone with a tight panel
Emporia Pro Level 2 EV Charger
The best-balanced 48 A charger for a typical US house: full 11.5 kW hardwired, and the only unit at this price that ships with a whole-home energy monitor so its load management is reading your actual panel rather than guessing.
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A house with rooftop solar
Enphase IQ EV Charger 2 (48 A)
The charger to buy if you have solar: it adjusts in 1 A increments to absorb whatever the array is exporting, and it carries a 5-year warranty, the longest here.
#ad Price as of October 5, 2026. How we make money
We earn commission on qualifying purchases at no cost to you. Affiliate disclosure.
Connector and adapters
The GMC Hummer EV uses a J1772 port for AC charging, which is what the large majority of home chargers in the US have. No adapter is needed for a J1772 charger.
You need a NACS to J1772 adapter only if you intend to use a Tesla Wall Connector, a Tesla Destination charger or a Tesla Mobile Connector. Rated headroom matters on a part carrying 48 A for eight hours — see best NACS to J1772 adapters.
A J1772 car on a Tesla Wall Connector or Destination charger
A2Z EV Stellar Plug NACS to J1772 AC Adapter
80 A / 19.2 kW rated, which is genuine headroom over any home charger. The part to buy if a Tesla charger is in the picture.
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Which Hummer do you have?
| Model year | Onboard charger | Max amps | Circuit to use it fully |
|---|---|---|---|
| 2022-2023 | 11.5 kW | 48 A | 60 A breaker, 6 AWG copper |
| 2024 onwards | 19.2 kW | 80 A | 100 A breaker, 3 AWG copper |
If you have a 2022 or 2023 car, the decision is simple: 48 A is the car's ceiling and the right install. If you have a 2024 or later car, read on.
What 80 amps requires, and why it is rare
An 80 A continuous load needs a 100 A two-pole breaker under NEC 625.41's 125% rule, and 3 AWG copper at the 75 degC column of Table 310.16. A 100 A continuous load is half of a 200 A service before general lighting, a range, HVAC or a water heater is counted.
This is a capacity problem rather than a cost problem. The conductor is expensive and the breaker is expensive, but what actually stops it is that the amps are not there. The fix is a service upgrade, and that is a different project — see panel upgrade cost.
What 48 amps actually delivers on a Hummer
| Charger | Power | Miles per hour | Hours for 150 miles |
|---|---|---|---|
| 32 A | 7.7 kW | 11 | 14h 05m |
| 40 A | 9.6 kW | 13 | 11h 18m |
| 48 A | 11.5 kW | 16 | 9h 26m |
| 80 A | 19.2 kW | 27 | 5h 39m |
Those are the longest charge times on this site, and they are a direct consequence of the efficiency figure. 16 miles of range per hour at 48 A means a 150-mile day takes most of an overnight window.
A 32 A charger on a Hummer is genuinely inadequate — fourteen hours for 150 miles does not fit in a night. This is the one vehicle on the site where we would say do not compromise below 48 A under any circumstances.
Load management matters more here than anywhere
A Hummer drawing 48 A for nine hours is the largest sustained load most houses will ever carry. If a load calculation on your service comes back anywhere near marginal, a charger that watches whole-home consumption and throttles is not a convenience feature — it is what makes the install viable without utility work.
NEC 625.42 explicitly permits an installation's rating to be limited through controls, which is the code basis. Our load calculation guide covers how to get a real number.
Bidirectional charging
The 19.2 kW onboard charger is what enables the 2024+ Hummer's bidirectional capability — up to 6 kW to another vehicle via an optional accessory, and GM's broader home energy offering. If bidirectional power is on your list, the conversation is about GM's home energy system rather than about a wall charger, and it involves considerably more than a circuit.
Our bidirectional charging page covers the category honestly, including what it currently does and does not deliver in US homes.
What to install
For a Hummer EV on a normal residential service
48 A units with load management, because that is what this vehicle plus a real house actually requires. Add a monitor first if your service is in any doubt.
Most households, and anyone with a tight panel
Emporia Pro Level 2 EV Charger
The best-balanced 48 A charger for a typical US house: full 11.5 kW hardwired, and the only unit at this price that ships with a whole-home energy monitor so its load management is reading your actual panel rather than guessing.
#ad Price as of October 5, 2026. How we make money
A house with rooftop solar
Enphase IQ EV Charger 2 (48 A)
The charger to buy if you have solar: it adjusts in 1 A increments to absorb whatever the array is exporting, and it carries a 5-year warranty, the longest here.
#ad Price as of October 5, 2026. How we make money
Knowing what your panel is actually doing
Emporia Vue 3 Home Energy Monitor
The cheapest way to replace a load calculation's assumptions with measurements. If your panel is marginal, a month of real data from this tells you whether a 48 A charger fits better than any rule of thumb will.
#ad Price as of October 5, 2026. How we make money
We earn commission on qualifying purchases at no cost to you. Affiliate disclosure.