Plug-in electric vehicles (PEVs) are powered by rechargable onboard battery packs, which use stored electricity to propel the vehicle. The battery packs can be charged from two types of outlets: Level 1 (120 volts) and Level 2 (240 volts).
The difference in voltage does not affect the amount of energy stored in the battery, but the rate at which the battery is charged.
DTE Energy will provide a 240-volt charging station to the first 2,500 customers who apply.
Level 1 Charging
Level 1 charging is done using a standard 120-volt outlet, which is the most commonly found outlet in a household. They supply alternating current (AC), which is used to power everything from alarm clocks to desktop computers.
PEVs may be plugged into a 120 volt outlet, providing a convenient, "anytime, anywhere" power source. Depending on the battery size and how far the vehicle was driven (e.g., how low the battery's charge is), Level 1 charging takes about 8 – 15 hours to fully charge the vehicle's battery.
Level 1 charging requires a dedicated 15 or 20 Amp outlet in the garage or other location where the vehicle will be charged.
Level 2 Charging
Level 2 charging is done using a 240 volt circuit, much like that used for an electric dryer, electric stove, or a central air conditioning system.
Most garages don’t have a 240 volt circuit so one would need to be installed to facilitate faster charging. The vehicle manufacturer may specify what Electrical Vehicle Supply Equipment (EVSE) should be used with their vehicle which will determine the exact equipment you should install. If the vehicle is kept outdoors, special, weather-proof, equipment may be needed.
Depending on the battery size and how far the vehicle was driven, Level 2 charging takes between 3 and 8 hours to fully charge a battery, or half the time of Level 1 charging.
Level 2 charging requires:
- A dedicated 240-volt outlet in the garage or location where the vehicle will be charged.
- Electrical Vehicle Supply Equipment (EVSE), installed in compliance with the National Electric Code (NEC) Article 625, and inspected.
Detroit Edison recommends that customers installing Level 2 charging equipment install a separately metered circuit (see pages 6-8) to serve this load. This will allow you to save even more on your vehicle’s fuel cost by charging your vehicle at lower off-peak prices using Detroit Edison’s optional electric vehicle rate.
For safety reasons, a licensed electrician should be called to perform the installation of the EVSE.