I'm confused by all this electrical talk, I need help!
If you'd like an excellent way of understanding basic electricity in only a few minutes, we highly recommend reading this:
Once you have read that, a simple explanation will now make sense. Since you are now likely a new electric vehicle owner, it would be a good idea to learn these basics.
Just as normal cars have gas tanks, EV's have battery packs. Whereas you might know how many gallons or liters your tank holds on a normal car, you should probably know how big your battery pack is on your EV. This is expressed in Watt-Hours, which is usually written kWh (Kilowatt-hours). This is also the same unit your home electric meter records. In the Nissan LEAF for example, your battery is 24kWh capacity, with about 21kWh usable. This basically means you can draw 21,000 watts for one hour. A LEAF uses around 15-25kW when driving on the highway, and it has a gauge that will show you your real-time consumption in miles/kWh. So if you get your consumption to around 21kW, this means you can drive for about an hour.
When recharging an EV battery, you need to know how fast the used kWh's can be replenished. If you have a charger that can output 1kW (1000 watt), then it will take approximately 21 hours to fully replenish your Nissan LEAF battery.
In the US, standard charge docks/cables are referred to as level 1 or level 2. Level 1 runs off of 120 volts, and Level 2 runs off 240 volts (at home). Since Amps X Volts = Watts, to get about 1kW from a standard 120 volt outlet, you need to pull about 8 to 9 amps. Volts is the "pressure" available and Amps is the current or flow. Since most home 120 volt outlets are only capable of sustaining about 12 amps continuously (safely), you are limited to 1.44kW or 1440 watts. This is why you absolutely need a 240 volt outlet to get faster charging.
Once connected to a 240 volt outlet the same 12 amps can provide double the charge rate (2.88kW), and since 240 volt outlets are often available at higher amperages, you can go even higher. Some of our upgraded EVSE's are capable of 24 amps when used on a 30 amp 240 volt outlet, and this gets you 5.76kW which is 4 times faster than the original Level 1 capability!
Hope this information is useful to understanding EV operation and charging. Feel free to contact us if you have any questions.