Refueling Made Practical: A Primer in Level 1, 2, and 3 Charging
Electric vehicles (EVs), like their internal combustion (IC) cousins, will vary in size, comfort, and look. Unlike IC vehicles, however, EVs can also offer a variety of “refill” rates. If you have downtime - at home, work, or play - you can charge at a slower rate. If you are out and about and want to refill like you would at a gas station - you can charge more quickly.
Charge “refill” time depends on the charging technology being used. Some charging stations charge at a high rate that allows a refill in minutes instead of hours. These stations are often called Level 3 or Direct Current (DC) chargers. These chargers are designed for public use and are typically larger and costlier than those designed for private use. Conversely, charging stations designed for private use are smaller, charge over several hours, and are priced affordably for purchase by individual consumers for installation, typically, in their home garage.
LEVEL 1 CHARGING. Level 1 charging is also known as “over-night charging” or “trickle charging,” and uses a vehicle connector mated with a standard single-phase 120VAC outlet - the same outlet you use with your blender, power drill, or clock radio. Charging your vehicle with a Level 1 connector can take anywhere from 8 to 30 hours, depending on the size of the battery and other factors1. Level 1 charging takes longer than other charging methods, but the benefit is that it generally doesn’t require a complex installation and is therefore considered a highly portable charging solution. Level 1 charging allows you to fill your battery anywhere using a common “wall outlet” and a standard vehicle connector that mates with that outlet.
LEVEL 2 CHARGING. Level 2 charging uses a 220VAC outlet, the standard outlet for larger home appliances such as washers or dryers. Unlike appliances, a Level 2 charging station requires additional safety features to accommodate frequent plugging and unplugging, and therefore requires “hard wiring” into the building. Level 2 charging requires a licensed electrician to install the 220 volt outlet as well as your home charging station.
The home charging station, often referred to by industry insiders as “Electric Vehicle Supply Equipment” (EVSE), is specially designed to charge at a higher current than Level 1 for safe, faster refill times. The Level 2 charging scheme can completely “refill” your vehicle in approximately 2-8 hours, depending on the size of the battery and other factors. Level 2 charging is not portable and requires a fixed, permanently wired installation, but it’s likely to be the most popular and often-used charging method. And for good reason: this charging regimen is also known as “opportunity charging,” because of its efficient use of downtime opportunities. Level 2 charging with a home charging station in your garage allows you to charge your EV while you sleep, eat, or enjoy your time with family. Level 2 charging stations can also be installed at corporate and retail locations, so you can conveniently charge your electric vehicle while shopping or working - further enhancing the practicality of EVs. Level 2 charging stations may also be used to recharge commercial fleets.
LEVEL 3 CHARGING. Level 3 “fast charge” stations use 3-phase, 400-600VAC electrical service and are capable of delivering a quick charge that mimics the refueling of a gas vehicle because they use Direct Current (DC). Fast charging is enabled by safe, high-current charge and can deliver a fully charged vehicle in as little as 10 minutes, depending on battery size, chemistry, and other factors. Level 3 charging will be the solution of choice for public EV charging infrastructure, supporting drivers on long trips or those who may find themselves out on the road and in need of a quick refuel. Level 3 charging may also serve commercial fleets and public transportation, which requires high-current charging to accommodate the refueling of extremely large batteries.
With so many re-charging options - at home, work, and on the road - electric vehicles have never been more convenient. The new generation of EVs will be supported by charging infrastructure solutions that will help drivers reclaim the time spent at the pump - and make practical zero-emission transportation a reality.
