EV charging research • Weber Ford • Greater St. Louis
Charging time depends on energy added and the average power reaching the battery. An overnight top-up, a large home recharge and a highway fast-charging stop are different jobs. Use the examples below to plan the job, then check the exact vehicle, equipment and conditions for your own estimate.
The Department of Energy’s charging overview describes charging levels and the factors that change time. A charger’s advertised power does not establish the speed that every connected vehicle receives.
| Charging method | Typical setting | What to verify |
|---|---|---|
| AC Level 1 | Compatible equipment using a suitable 120-volt supply | Available power, outlet/circuit suitability and whether the parking window replenishes your driving |
| AC Level 2 | Compatible 240-volt home or 208-volt commercial equipment | Installed power, vehicle AC limit and the energy needed during that parking window |
| DC fast charging | Compatible public or commercial charging equipment | Vehicle DC capability, connector/approved adapter, battery condition and the specified charge interval |
Kilowatt-hours, written kWh, measure energy. Kilowatts, written kW, measure power. To estimate energy from the battery display, multiply usable battery capacity by the difference between the target and starting state of charge, expressed as a fraction.
For a hypothetical 80-kWh usable battery going from 20% to 80%, the calculation is 80 × (0.80 −0.20) =48 kWh. These are assumed numbers, not a Ford battery specification. Use usable capacity rather than assuming an advertised total capacity is entirely available.
A normal commute may require much less than that. Estimate the energy needed to replace the day’s driving instead of planning every night as an empty-to-full session. The vehicle’s charge estimate is useful because it can account for conditions that a simple calculation omits.
The baseline calculation is energy to add ÷ average battery-charging power = hours. The table assumes steady average power delivered into the battery. It is arithmetic for comparison, not a forecast for a charging level, vehicle or station.
| Energy to add | At 1.2 kW average | At 6 kW average | At 9.6 kW average |
|---|---|---|---|
| 12 kWh | 10 hours | 2 hours | 1.25 hours |
| 24 kWh | 20 hours | 4 hours | 2.5 hours |
| 48 kWh | 40 hours | 8 hours | 5 hours |
If your starting number is an equipment rating or power drawn from the wall, it is not automatically the net power stored in the battery. Energy can be used by conversion losses, battery temperature management and other vehicle loads. Do not silently treat a wall-power figure as a battery-power figure.
For another illustration, assume 6 kW from the wall and an assumed 90% reaching the battery on average. Net power would be 5.4 kW, so 24 kWh ÷5.4 is about 4.44 hours. The 90% value is invented for the example; actual efficiency varies. If your input already represents net battery power, do not apply that loss allowance again.
The effective charging power also depends on the electrical supply, charging equipment and the vehicle’s acceptance limit. A higher-rated station cannot force a vehicle to accept power beyond its capability. Ask for the AC limit when planning home charging and the DC capability when planning highway stops.
DC charging power changes over a session. Starting charge, battery temperature, vehicle limits, station performance and the intended target all matter. Power often falls as the battery approaches a higher state of charge, so extending a partial-charge result to 100% with simple multiplication can mislead.
Read the complete interval and conditions whenever a manufacturer publishes a charging time. A 10–80% example and a 0–100% charge are different comparisons. Follow the vehicle’s instructions for route planning and battery preparation where supported; do not assume every EV has the same preparation features.
For a Ford SUV example with its model-year conditions, use our separate Mustang Mach-E range and charging guide. This general worksheet does not replace those specifications.
At home, compare a normal day’s energy use with the dependable hours the vehicle will remain parked. Check any charge schedule, target setting and departure requirement. Confirm which cord or charging equipment is included with the actual vehicle before purchasing additional hardware.
For travel, check compatible stations along the route, current access and pricing, plus an alternative location. Plan around the energy needed to reach the next stop or destination. Include the possibility of waiting, an unavailable charger or a slower session; the calculated charging time alone does not describe the entire stop.
Use the battery-life and charging-care guide for manufacturer-specific daily targets and storage questions. The hybrid-versus-electric comparison helps decide whether a plug-in routine fits at all.
No. The vehicle’s limit and the actual station and battery conditions control delivered power. A maximum station rating is not an average charging rate.
No. That arithmetic works only if average power into the battery actually doubles for the same energy added. Vehicle limits, changing power and conditions can prevent that.
No. They are planning arithmetic. Have the vehicle, approved equipment and electrical installation checked for the actual application.
Tell us your daily mileage, parking arrangement, typical charging window and the EV or PHEV you are considering. Include a stock number if you have one. We can help identify the vehicle questions to resolve before you plan a visit to Granite City or buy charging equipment.
