Where 11 kW comes from, and why your charger says 48
Two different conventions collide in this query, and knowing which one you are reading removes most of the confusion.
Cars are rated in kilowattsbecause an onboard charger is a power converter and watts are the honest unit for one. Your car’s figure is a ceiling: it is the most AC power the car can turn into stored charge, regardless of what you plug it into.
North American chargers are rated in amps because what you are really buying is a load on a 240-volt single-phase circuit, and the breaker that protects it is sized in amps. Multiply and you get the bridge: 32 A is 7.7 kW, 40 A is 9.6 kW, 48 A is 11.5 kW, 50 A is 12 kW, 80 A is 19.2 kW.
Eleven kilowatts sits between two rungs.11,000 ÷ 240 is 45.8 amps. No charger is built at 46 amps, and under the National Electrical Code’s 125% continuous-load rule a 46-amp charger would need a 57.5-amp breaker, which is not a standard size. So the market builds 40 and 48, and a car rated 11 kW is served by a 48-amp charger with a little headroom to spare.
The reason 11 kW is everywhere anyway is three-phase power. Sixteen amps on each of three phases is roughly 11 kW, which is the standard European home charger, and global vehicle programs quote the figure their biggest market uses. It tells you nothing bad about the car and nothing useful about which American charger to buy.
What we ranked on
With the output fixed at 11.5 kW across the field, speed stops being a differentiator and four other questions decide the purchase.
One: does the maker publish the figure, or only the amperage?This sounds pedantic and is not — it is the cleanest available signal about how much a brand documents. Lectron publishes “up to 48 amps at 240V (11.5 kW)” and, on the J1772 Nexus page, the precise 11.52 kW. Grizzl-E’s spec table reads “Max power 48A 11.5 kW”. Wallbox publishes “Up to 11.5kW”. Emporia publishes “Up to 48A” and leaves you to do the arithmetic. ChargePoint publishes 12 kW at 50 A, with 48 A as one of six app-selectable steps.
Two: is it hardwired, and does the maker say so plainly?Forty-eight amps cannot be plugged into a NEMA 14-50, so almost everything here is a permanent install. Lectron publishes “hardwire-only” on both Nexus units and states installation must be by a licensed electrician on a dedicated 240 V circuit. Grizzl-E publishes “Hardwire Only”. The Emporia is the exception worth knowing about: Emporia publishes “NEMA Plug or Hardwire” for the same unit, so it is 40 amps on a plug now and 48 amps hardwired later as one purchase — the only hedge of its kind in our registry. ChargePoint sells both routes too but publishes that its plug-in SKUs cap at 40 A. Hardwired vs plug-in covers the wider trade-off.
Three: what does it publish about the enclosure and the cold?With everything else equal, this is where the field genuinely separates, and the pattern is that each maker publishes what the others omit. Grizzl-E publishes a UL Type 4 indoor/outdoor rating, an aluminum enclosure, -30°C to +50°C (-22°F to 122°F) and 25 feet of cable, and publishes no ENERGY STAR certification. Lectron publishes IP66 weatherproof housing, a 23-foot cable of 15.0 mm compound it states stays flexible in freezing weather, ETL listing to UL 2594, UL 2231 and UL 2251 plus ENERGY STAR and FCC — and publishes no operating-temperature range at all. Emporia publishes a NEMA 4 enclosure, UL listing, ENERGY STAR and 25 feet. We report both halves, the figures and the absences. NEMA and IP ratings explained covers what each code promises.
Four: can you turn it down?An adjustable charger is worth more than a nameplate figure, because the circuit your panel can spare may not be 60 amps. Grizzl-E publishes selectable 48/40/32/24/16 A by DIP switch. ChargePoint publishes six app-selected steps at 16, 24, 32, 40, 48 and 50 A. Lectron publishes no adjustable current list for the Nexus at all — the 48 A rating is the only figure on the page, which is an absence rather than a flaw but matters if your service is tight. The adjustable-amperage roundup ranks the whole field on this one spec.
The five cars that produced this question
Everything above is about chargers. Here is the car side, taken only from manufacturer pages we have read and dated, because this is the half that decides whether 11.5 kW is money well spent.
Toyota bZ — the only car here with 11 kW in plain text.Toyota’s own 2027 bZ page states “The 11-kW onboard AC charger allows you to take advantage of its Level 2 charging capability to charge your vehicle from 10% to 100% in around seven hours.” It also publishes a NACS charging port with included CCS1 and J1772 adapters. Our bZ page works through what that means for which connector to buy.
Volkswagen ID.4 — 11 kW, and the most useful honesty on this page. VW’s disclaimer reads “Vehicle maximum AC acceptance rate is 11kW”, and the same page states the included 2-in-1 cable manages “approx. 9.6kW for up to 27 miles per hour” on a 240 V outlet while quoting “up to 8 hours” empty to full at 11 kW. In other words VW ships 83% of what the car accepts and still calls the overnight charge eight hours. Our ID.4 pagehas the full arithmetic, including why VW’s own NACS-adapter footnote rules out the NACS picks for that car.
Kia EV6 and EV9 — 10.9 kW, and an internal contradiction we publish. Kia prints “Onboard Charger Power 10.9 kW” on every 2026 trim of both cars, then labels its own Level 2 charge-time row “@ 240V / 11kw via Electric Vehicle Supply Equipment”. Both figures are Kia’s; we report the gap rather than picking a side. The EV6 page and the EV9 page reach opposite conclusions about amperage from the identical module, because efficiency differs.
Hyundai IONIQ 6 — 10.9 kW, quoted through a charge time.Hyundai publishes “Approximately 6 hours and 55 minutes to charge from 10% to 80% on a 10.9-kW, 240V AC charger”, which is the only named AC charger power on any Hyundai page we have read. It is also, usefully, Hyundai describing the charger rather than the car — and 10.9 kW is about 45 amps. Our IONIQ 6 page has the detail.
Cadillac LYRIQ — 11.5 kW, and the one real case for going higher. Cadillac lists an “11.5 kW AC onboard charging module” on the Luxury trim and the LYRIQ-V, and a “19.2 kW AC onboard charging module” on the dual-motor trims. If you own one of those, you are the rare buyer for whom 48 amps is genuinely the constraint — the LYRIQ page and 48 vs 80 amps are the two pages to read next.
When 11.5 kW is the wrong answer
Three situations, and together they cover most houses.
You already have a NEMA 14-50 receptacle. Then your ceiling is 40 amps and 9.6 kW, because a 14-50 sits on a 50-amp circuit and the NEC caps a continuous load at 80% of it. Replacing that circuit to gain six miles of range an hour is rarely worth the labor. The 14-50 roundup is your page.
Your service is 100 amps.A 60-amp dedicated circuit is 60% of a 100-amp service, which usually fails a load calculation before it fails anything else. The answer is either a lower amperage setting or a charger that manages the whole-home load dynamically — the small-panel roundup and the panel-capacity guide work through the calculation before you spend anything.
Your car accepts less than 11 kW.Plenty do, and plug-in hybrids are dramatically lower — often 3.3 to 7.7 kW. Buying 48 amps for a car that accepts 32 is money spent on current that never leaves the box. What size charger do I need and the plug-in hybrid picks size it honestly.
One thing that is not on that list: wanting the charger to outlive the car. A 48-amp hardwired unit on a 60-amp circuit is the specification most new EVs will keep asking for, and the circuit is the expensive half to revisit. If you are paying an electrician anyway, 11.5 kW is the right place to land.
