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Charging Options and Basic Circuit Requirements (EV)

Source: Various

As the market for Electric Vehicles begins to blossom, EV drivers will need a reliable and convenient way to charge their vehicles at and away from home.

There are three levels of charging stations:

  • Level I Charging: Uses a standard grounded, three-prong 120-volt house outlet and requires a 15 to 20 amp fuse on the outlet used for charging the vehicle.
    • 120V@16A
    • Standard NEMA 5-20R outlet
    • Charges at approximately 1 kW per hour
    • Most PEV’s full charge at level 1 in eight to 10 hours
    • BEVs take 12 to 24 hours to fully charge
  • Level II Charging:  Uses a 240-volt circuit similar to what an electric stove or central air conditioning system use.  Industry experts recommend a 40-amp fuse.
    • 208/240V@32A circuit
    • SAEJ1772 connector
    • Charges at approximately 7 kW per hour
    • Charging usually takes half the time of level 1
    • Charges at approximately 7 kW per hour
    • May require a panel upgrade
    • Must purchase the Electrical Vehicle Supply Equipment (EVSE) recommended for the vehicle
    • Must hire a qualified electrician to perform the installation
  • Level III Charging: The connector standard is not yet established.
    • 480V@125A circuit
    • Capable of delivering a full charge in 15-30 minutes
    • Public charging sites

Networked Charge Station Manufacturers (Public)

Coulomb Technologies developed the ChargePoint Network consisting of electric vehicle charging stations, communications network, and a network operating system.  The ChargePoint Network employs a Flex Billing System (effective July 2010) which provides tools for hosts, or owners, to set pricing at individual ChargePoints as a function of time of day, calendar date, and driver.  Owners of the ChargePoints enter into a profit-sharing arrangement where Coulomb will collect, process, and forward 80% of revenues to hosts.  Charging sessions can also be provided free of charge if the owner of the unit chooses to do so (electricity and annual maintenance costs will still be incurred by the host). Customers can pay via ChargePoint smart card, by filling the card online or credit card, by calling a toll free number.  Coulomb Technologies has provided San Francisco, Chicago, and Nashville with ChargePoints for their government fleet vehicles. Coulomb is currently developing a Level III Networked Fast Charging Station, which will be available third quarter 2010.  The expected cost is approximately $40,000 for equipment and $20,000 to install[1].

Better Place offers the option of recharging at a charging station or battery replacement.  Better Place deploys a number of battery exchange facilities and charging stations in Denmark and Israel, and they begun negotiations with local government agencies within the U.S.[2]  Battery swapping stations will resemble a carwash and cost approximately $500,000 to build.[3]  Better Place customers will not own battery packs, they will pay for miles driven, which will include the electricity, use of battery pack, and access to charging stations and quick-swap facilities.  A range of pricing-plans will be available, such as a $375 per month plan that permits up to 18,000 miles a year or a $500 per month plan that permits unlimited annual mileage.[4] 

ECOtality, Inc announced on October 13, 2010, that BP Products would install ECOtality’s Blink electric vehicle DC Fast Chargers at 45 BP and ARCO locations, which will be available to the public as early as March 2011.[5]  The Blink charger is the highest-power charging station currently on the market, and is capable of providing a full charge in less than 30 minutes.  The dual port design ensures maximum availability and provides intelligent, user-friendly features, such as easy payment options, interactive touch screen displays and web-based information delivery.  The Blink charger will sell for $2,500 to corporate customers and $1,199 for residential customers.[6] Options include programming it to charge from s Smartphone and to charge where there are dips in electricity price.  The utility can also control when to charge the car during the night.

Non-Networked Charge Station Manufacturers (Home/Fleet)

Aerovironment Inc. (AV) creates test systems and charging systems designed to make electric vehicles more practical.  AV collaborated with Nissan to install Level II home charging units for all-electric LEAF purchasers, programmed to operate during off-peak hours.  AV is currently working with Th!nk, an electric vehicle manufacturer entering the US market, to develop a Level III fast charging station able to recharge from completely depleted to 80% charged in only 15 minutes.[7]

Clipper Creek, Inc. produces high-rate charging stations.  These stations are recommended for home use and can be configured to only charge at certain times.  Clipper Creek partnered with BMW to provide charging units to individuals participating in the Mini-E Test Lease program.

ECOtality will qualify 8,300 Nissan LEAF and Chevrolet Volt customers for participation in the EV Project based upon home electrical power capabilities.  Participants will receive the home Electric Vehicle Supply Equipment (EVSE) and up to $1,200 credit towards the installation in


Basic Charging Circuit Requirements:
Source: U.S. Department of Energy

Charging Hybrid Electric Vehicles (PHEVs) and All-electric Vehicles (EVs) requires plugging into Electric Vehicle Supply Equipment (EVSE). 

Charging times vary based on how empty the battery is, how much energy it holds, battery type, and the type of charging equipment used. 

Charging equipment: 

Level 1 equipment uses a 120 volt (V), alternating current (AC) plug (up to 15 amperes and 1.8 kW) and require a dedicated circuit.  Level 1 ECSE is portable and does not require installation of charging equipment.  On one end of the cord is a standard, three-prong household plug.  On the other end is a connector, which plugs into the vehicle.  Level 1 charging can take from 8 to 20 hours for a full charge, adding about 5 to 6 miles of range per hour of charging time, depending on the vehicle.

Level 2 equipment uses a 240 V, AC plug (up to 80 amperes and 19.2 kW) and requires the installation of a charging unit.  However, most residential level 2 EVSE will operate at lower power, using 30 amperes and delivering 7.2 kW of power.  Level 2 charging can take from3 to 8 hours to reach a full charge, adding about 25 miles of range per hour of charging time, depending on the vehicle.

Level 3 equipment is still in development.  It will enable a faster AC charging option that will operate at a higher voltage and current than Level 2.   Level 3 charging stations will be installed in public locations.  Level 3 charging can take less than 30 minutes to reach a full charge.

Basic charging requirements:  











Standard Outlet

Level 1






NEMA 5-15R

Level 2






SAE J1772/3

Level 3







 Connectors and plugs:

Modern charging equipment and vehicles use a stand connector and plug receptacle based on the Society of Automotive Engineers (SAE) J1772 standard.  Vehicles with this plug receptacle can use any Level 2 or Level 2 EVSE. Major vehicle and charging system manufactures support this standard, which should eliminate drivers’ concerns about whether their vehicle is compatible with the infrastructure. 

At this time, no standards exist for Level 3 EVSE.

Equipment:  For a list of charging units and other accessories, go to http://www.pluginamerica.org/accessory-tracker?ul=listed.

[1] http://green.autoblog.com/2010/01/16/coulombs-gas-pump-chargepoint-ups-the-ante-with-30-minute-ele/

[2] http://blogs.edmunds.com/greencaradvisor/2009/10/california-utilities-divided-on-state-regulation-of-ev-charging-station-providers.html

[3] http://www.businessinsider.com/the-cost-of-a-better-place-battery-swapping-station-500000-2009-4

[4] These figures are estimates.  http://www.greencarreports.com/blog/1035839_driving-electric-to-cost-no-more-than-using-gas-says-better-place

[6] http://blogs.forbes.com/velocity/2010/07/27/another-stylish-electric-vehicle-charger-enters-the-fray/?partner=yahootix

[7] http://www.treehugger.com/files/2010/02/think-aerovironment-ev-charging.php