EV charger
How much electricity does an EV charger use?
1.4–11 kW · 20–80 kWh per full charge · $8–$20 per charge
An EV charger's electricity use is not about time — it is about how many kWh you put into the battery. A 60 kWh battery charged from 20% to 80% needs about 45 kWh, and at 16.5¢/kWh that is roughly $7.40.
Charger types and draw
- Level 1 (household socket): 1.4–1.8 kW — about 5 miles of range per hour
- Level 2 (7 kW): 7.2 kW — about 25 miles per hour, a full overnight charge
- Level 2 (11 kW, three-phase): 11 kW — about 40 miles per hour
- DC fast charging: 50–350 kW, not typically residential
Cost per mile vs petrol
An efficient EV uses about 0.28 kWh per mile. At 16.5¢/kWh that is roughly 4.6 cents per mile. A petrol car at 35 mpg and $3.50/gallon is about 10 cents per mile. The gap widens further on an off-peak EV tariff, where the rate can drop to 7–9¢/kWh.
Charging losses
Not all electricity from the wall reaches the battery. Level 2 charging is about 88–92% efficient; Level 1 is lower, around 80–85%, because the car's onboard charger works harder. The calculator above should use the wall draw, not the battery figure.
Grid impact at home
An 11 kW charger uses more than half the capacity of a typical 100 A service. Most homes can charge at 7 kW overnight without an upgrade; higher rates often require a load calculation and sometimes a panel upgrade.
Frequently asked questions
How many watts does a ev charger use?
1.4–11 kW. The figure on the rating label is the maximum draw; actual use varies with settings, age and usage pattern.
How much does it cost to run a ev charger per month?
With the defaults above it comes to the monthly figure shown in the calculator. At 16.5¢/kWh — the US residential average — that is a realistic middle estimate. Your own bill may be 30% lower or higher depending on state.
Is it cheaper to run a ev charger at night?
Only if your utility offers a time-of-use plan and you avoid the 4pm–9pm peak window. On a flat-rate plan, the time of day makes no difference to the total.
Does the calculator account for real-world duty cycles?
Not automatically — you enter the effective hours yourself. For compressing appliances like refrigerators and AC units, enter the running watts and roughly the proportion of time the compressor is on, which is usually 30–50%.
Will a newer ev charger actually save money?
Compare the kWh figure in the calculator against an Energy Star model's stated annual use. If the difference is a few hundred kWh a year, the payback on a replacement is usually long; if it is over 500 kWh, it is worth pricing out.