EV Terminology & Recomendations for EV Charging Infrastructure

By Michael Bornstein

The following was prepared by Michael Bornstein PhD, MD for use in planning future Electric Vehicle (EV) charge stations in Kern County, California. I am posting it because it is an excellent primer on EV terminology and includes several astute recommendations designed to aid in locating new charging infrastructure not only in Kern County, but anywhere. Michael drives a Rav4 EV.—Paul Gipe

In order to understand Electric Car Charging and the infrastructure needed, we first have to understand the terminology.

EV – Electric Vehicle.  An electric car.

BEV – Battery Electric Vehicle.  These cars have no gasoline engine, but instead run totally on batteries.  Examples are the Nissan Leaf, the Toyota RAV4 EV, and the TESLA Model S

PHEV – Plug-in Hybrid Electric Vehicle.  These cars are hybrids, but allow the battery to be charged by plugging in.  An example is the Toyora Plug-in Prius (PIP).  The electric only range of the PIP is only 11 miles and even then the ICE will run as the electric motor is not powerful enough to run the car.

EREV – Extended Range Electric Vehicle.  This is a BEV with an ICE that acts as a generator to recharge the battery.  The primary source of power to the wheels is from the electric motor.  The ICE only powers the car under extreme conditions (climbing steep hills or traveling at over 70 mph), otherwise it is just a battery charger.  A Chevrolet Volt is an EREV with a battery only range of 40 miles.

Hybrid – An ICE car with an electric motor that gives a little extra energy to the wheels.  The battery is charge by recovering energy when the car slows down.  The primary source of power to the wheels is the ICE.  The Toyota Prius is a Hybrid.

ICE – Internal Combustion Engine.  A standard gasoline or diesel engine car.  Can also be used as a verb or adverb , for instance when an EV only parking spot is occupied by an ICE, it is said to be ICE’d.

kW – Killowatt.  This is a unit of power, or energy delivered over a unit of time (kWh/h).  It is used as a rating of battery chargers and of the battery’s ability to supply power to the engine.

kWh – Killowatt-Hour.  This is a unit of energy, the amount of energy a battery can hold or deliver. Often the manufacturer limits the energy output of the battery to less than its actual capacity so that the user won’t notice battery degradation.   The Volt has effectively an 11 kWh battery although its capacity is actually 17 kWh, the Leaf a 24 kWh battery, the RAV4 a 41 kWh battery, and the TESLA S-85 has an 85 kWh battery.

EVSE – Electric Vehicle Supply Equipment.  This is mistakenly called a “charger” most of the time.  The EVSE handles the handshake between the charger in the car and the power source in the wall.  It delivers 120VAC or 208-240VAC to the car, and tells the car the maximum number of Amps that it can deliver.

Charger – This is a device in the car that takes AC Volts from the EVSE and converts it to approximately 400VDC to charge the batteries.  Chargers are rated in kW, and since they are part of the car, they are very difficult to upgrade.  Popular chargers will accept 3.3 kW (older Leafs, Volts), 6.6 kW (newer Leafs), 9.6 kW (RAV4 EV, Mercedes Model B, TESLA) or 19.2 kW (option on TESLA).  This is the maximum they will accept.  If the EVSE is rated lower, they will take the lower amount.

Level 1 (L1) – This is an EVSE designed to deliver 120VAC.  Typically they are rated at 8 or 12A (0.96 or 1.44 kW) but some will deliver 16A (1.92 kW).  The TESLA charger in the Model S and the RAV4 will accept up to 20A (2.4 kW).

Level 2 (L2) – This is an EVSE designed to deliver 208-240V typically at 14-40A although some are designed to deliver 70-80A specifically for the TESLA.  Most public chargers are 30A.  Leviton makes a 40A EVSE specifically for the 9.6 kW charger in the TESLA and the RAV4.  Power consumption is therefore between 2.9 kW (208V @ 14A) to 9.6 kW (240V @ 40A)

Level 3 (L3) – This is a charger, not an EVSE.  It takes input power (240-408VAC) and converts it to approximately 400VDC to deliver directly to the battery in the car.  Currents range up to 125A (50 kW).Only a few cars can accept this charger, specifically the LEAF and the Chevrolet Spark EV.  There are two systems available, CHAdeMO (Japanese) and SAE (American/European) (think Betamax vs. VHS).  The CHAdeMO is the worldwide standard with the most installed chargers and the most equipped cars by far.  Older chargers in the US are CHAdeMO.  Newer “Combo” chargers have  both CHAdeMO and SAE cables.  There are no SAE only chargers (except at certain car dealers).  Another name for an L3 charger is DCFC – Direct Current Fast Charge. 

SuperCharger – A TESLA specific charger similar to L3 but at much higher currents.  Only certain Model S TESLAs can use these stations.  It can recharge an 85 kWh car to 80% in 30 minutes.

Current  EVSE’s in Bakersfield

There are very few public EVSE’s in Bakersfield.  Most of them are at car dealers, most of these are only available to the specific brand of the dealer, sometimes only to the dealers customers.  These EVSE’s tend to be L2 EVSE’s @ 30A, partly because very few cars can utilize a 40A EVSE (TESLA & Toyota), and partly because the dealer wants to get the customer to charge and leave as soon as possible.  The dealers include:

Jim Burke Ford at both locations

Bakersfield Nissan – they have both L2 and L3 equipment

Barber Honda

Bakersfield Mitsubishi

Fiat of Bakersfield

BMW Bakersfield

Other sites with EVSE’s include:

Hampton Inn I-5 @ 7th Standard Road

Bakersfield Palms RV Resort Fairfax & Edison – They supply the 240V, you must bring your own EVSE

Crest Drive-in RV Park on Wible – They supply the 240V, you must bring your own EVSE

Houchin Community Blood Bank – you literally have to give blood to get a charge (and this is no joke)


Chargers can be divided into those applicable for short term parking, medium term, and long term.  An L1 EVSE will supply sufficient charge for a 40 mile drive after 8 hours of charging.  This makes it ideal for employees.  A low current L2 EVSE will give 40 mile range in 4 hours and thus would be helpful for students who are parked for only a few hours a day.  A 30A or 40A EVSE would attract people who park their cars just for the charge.  The lower power requirements of L1 and 14A L2 chargers would reduce the load on the school’s system allowing more EVSE’s to be installed for the same total load.

Other Points to Consider

Covered parking or an awning over the EVSE’s would be helpful as the batteries are temperature sensitive and do better at cooler temperatures (out of the Bakersfield sun).

DO NOT place the EVSE’s in prime parking locations where they are likely to be ICE’d!  An EV driver would rather walk a little rather than see an ICE car in an EV slot. Similarly, don’t combine EV spots with handicap spots for the same reason.  Place appropriate signage and instruct Security to ticket and possibly tow cars that are inappropriately parked.  Straight-in parking is preferred over angled parking as some cars have their charging ports towards the rear of the car necessitating them to back into the parking spot.  Placing the units at every other spot allows two cars to access the EVSE, useful if one spot is ICE’d or if one car has finished charging.

A company called Telefonix makes commercial L1 and 14A L2 chargers.  Their L1 units are only $1495, they don’t quote a price for the L2’s on the internet. I have included data on their L1 and L2 EVSE’s.  Another company that makes quality 15A and 30A L2 EVSE’s is ClipperCreek.  I have included data on their 15A unit.

L1 PowerPost

The L1 PowerPost™ EV charger has revolutionized the electric vehicle charging space. The L1 PowerPost EVSE was the fi­rst commercial Level 1 charging station with retractable cable technology.

Born from our belief that EV charging should be simple and affordable, the L1 PowerPost charging station delivers low current charging to vehicles parked for longer periods of time (4 or more hours on average) in a user-friendly, intuitive design.

Its Level 1 120V/16A specifi­cations make it possible to utilize a dedicated 20 amp circuit that is common in all commercial locations. For many situations, Level 1 charging is the right ­choice, enabling EV drivers to recover a 20-mile commute in just about 4 hours and at a cost to the facility of under $1.

L2 PowerPost

Many situations require Level 2 charging. Keeping our focus on charging stations designed especially for longer-term parking, Telefonix created the L2 PowerPost™ EVSE to deliver Level 2 charging with low-current.

Featuring the same proven, retractable cord reel technology that has helped make our groundbreaking L1 PowerPost EVSE a success, the L2 PowerPost EVSE also requires a 20 amp circuit but at 208 to 240 vac. This lower current, Level 2 unit allows for the installation of more charging stations with a given electrical supply capacity. At the same time, it will satisfy EV drivers looking to replace the range lost during their daily commute.

Although higher current Level 2 charging stations can quickly replenish the range of a typical 20-mile commute, those units are more expensive and risk spikes in energy demand that can affect a facility’s overall energy costs. For longer term parking where electric vehicles are parked for 2 hours or more, the 3.3 kW charging rate of the L2 PowerPost EVSE is the most sensible solution for delivering energy to cars and having a minimal economic impact on the facility. EV drivers typically put 10 to 12 miles of range back into their battery for every hour they are plugged into the L2 PowerPost EVSE. 2 hours of charging with the L2 PowerPost will replace the range lost during a 20-mile commute at an energy cost of about $1. Workplaces, airports and train stations are just some the applications that are perfect for the L2 PowerPost EVSE. Malls, retail outlets and theaters can also benefi­t by providing a valuable convenience to customers that drive EVs.

ClipperCreek LCS-20

The ClipperCreek LCS-20 provides 15 amps continuously at 240 volts, delivering up to 3.6 kW to the EV.

  • Charging Amperage: 15A (3.6kW max)
  • Supply Circuit: 208/240V, 20A
  • Installation: Hardwired, holster included
  • Cord Length: 22 feet
  • Enclosure: NEMA 4; indoor/outdoor rated, fully sealed
  • Warranty: 3 years
  • Certifications: ETL, cETL
  • Dimensions: 11”L x 4”W x 3”D