Understanding Home and Public Electric Vehicle Charging Stations

Charging electric vehicles is quite a change from the more traditional method of filling up on gas. With networks of public charging stations and home installed private charging stations available, we’ll take a look at the differences and how to utilize both.

While the number of available public electric vehicle charging stations is growing, over 90% of car charging is actually done at home. Home charging provides a certainty in terms of a reliable location to charge, even allowing users to charge their cars overnight.  There are several ways to charge at home – one option is to simply plug into a standard three-prong 120-volt electrical outlet. Since electric vehicles have what’s called an “onboard charger” built-in, it’s necessary to use the charging cord that comes with the vehicle to connect to a source of electricity.

EVSE Charging Stations

Plugging into a standard 120-volt wall outlet will not provide the quickest charge. Charging via this method typically adds about 4 miles of charge or driving range per one hour of charging time. To get a faster charge, most people will seek out a home EVSE, or “Electric Vehicle Service Equipment” solution.

An EVSE is any device that brings AC power to a car, where it is turned into DC power, filling the car’s battery using the onboard charger.

Because electric cars from respective manufacturers are built with various battery sizes and power applications, the maximum charging capacity and charging speed can differ.

Model Max Charge Miles added per hour Electric or Plug-in Hybrid Electric Vehicle (PHEV)
Audi A3 e-tron 3.3 kW 11 PHEV
BMW i3 7.4 kW 25 100% Electric / REx
Cadillac ELR 3.3 kW 11 PHEV
Chevy Spark EV 3.3 kW 11 100% Electric
Chevy Volt 3.3 kW 11 PHEV
Fiat 500e 6.6 kW 22 100% Electric
Ford C-Max Energi 3.3 kW 11 PHEV
Ford Fusion Energi 3.3 kW 11 PHEV
Ford Focus Electric 6.6 kW 22 100% Electric
Honda Accord Plug-In Hybrid 6.6 kW 22 PHEV
Hyundai Sonata Plug-in Hybrid 3.3 kW 11 PHEV
Kia Soul EV 6.6 kW 22 100% Electric
Mercedes B-Class Electric 10 kW 29 100% Electric
Mercedes S550 Plug-in Hybrid 3.3 kW 11 PHEV
Mercedes C350 Plug-in Hybrid 3.3 kW 11 PHEV
Mitsubishi i-MiEV 3.3 kW 11 100% Electric
Nissan LEAF 3.3 kW / 6.6 kW 11 / 22 100% Electric
Porsche Cayenne S E-Hybrid 3.6 kW / 7.2 kW 12 / 24 PHEV
Porsche Panamera S E-Hybrid 3 kW 10 PHEV
Smart Electric Drive 3.3 kW 11 100% Electric
Tesla Model S 10 kW / 20 kW 29 / 58 100% Electric
Tesla Model X 10 kW / 20 kW 29 / 58 100% Electric
Toyota Prius Plug-In 3.3 kW 11 PHEV
Volkswagen e-Golf 3.6 kW / 7.2 kW 12 / 24 100% Electric

Public Charging Stations – Locations and Rates

While charging stations are available in several locations such as shopping centers and office buildings, they may not stand out. For this reason it may be necessary to find a website or app to help locate EV charging stations. Note that public charging stations can vary – some may be free, but others are not. Some charge cars faster than others and some cars need different types of charging ports.

There are several electric vehicle charging stations available including those offered by ChargePoint and Schneider Electric. Generally speaking, to use different charging station networks, a card is needed. These cards are relatively easy to acquire; simply find a charging network’s website and register for an account.

Rates vary – there may be rates based on hourly use, session use, monthly use or annual rates. Many public charging stations, however, are free.

Rates vary for each charging station.

Charger Levels

One important factor to consider is the rate of charging can differ depending on the battery’s current charge level. For instance, the closer the battery is to empty, the quicker the flow of electricity is. As it fills, the rate slows – this is known as “tapering”, and it is noticeable around the 50% mark of a charge. The closer a charge is to 100% or fully charged, the slower charging will continue due to tapering. For this reason, many manufacturers recommend a fill to 80% as the most ideal – in fact, many public charging stations cut off charging at 80% as well.

There are different levels of car chargers –Level 1 is 120V, Level 2 is 240V and Level 3 is 480V.

  • Level 1 charging simply requires plugging the car into an ordinary 120-volt electrical outlet with the vehicle’s included cord. This option takes about 22 hours for a full charge.
  • Level 2 charging supplies 240V, about what an electric dryer or oven uses.
  • Both Level 1 and Level 2 charging stations deliver household electricity to the vehicle.

Level 1 and level 2 chargers have the same plug configuration called a J1172/SAE and Level 3 has a CHAdeMO plug. Level 2 chargers are the most common type used at home or public facilities. Level 3 chargers are known as DC fast chargers and are faster than level 2. They aren’t technically called “level 3” chargers since level 1 and level 2 chargers provide AC electricity to a vehicle via the onboard charger while these faster chargers bypass the onboard charger and provide DC electricity to the battery via a special charging port. Since Tesla Supercharging is much faster than “level 3” charging, it can be considered “level 4” charging. Level 3 is not compatible with all electric vehicles, and level 4 is the most restrictive in terms of how many different types of electric vehicles can be charged using a level 4 charger. Level 3 and 4 chargers are scarce – most public chargers are level 2.

For more information on electric vehicle charging stations and networks, call to speak with one of our application consultants at 1-800-STEINER (783-4637).