Charging 101 – Understanding the Basics

Convenience retailers interested in providing electricity to drivers of electric vehicles need to understand the business into which they are entering. 

June 9, 2020  read

Convenience retailers interested in providing electricity to drivers of electric vehicles need to understand the business into which they are entering. The fundamentals of servicing EV drivers includes types of charging services, methods of sale and options providing various levels of support.

Types of Electric Vehicles

The term electric vehicle (EV) is often applied without specificity to a broad range of potential vehicles. The “electrified” vehicle market includes three primary variations: 

  • Hybrid Electric Vehicles (HEV) – Hybrid vehicles are those equipped with a battery system that provides additional power to a traditional vehicle that relies primarily on an internal combustion engine. Sometimes these vehicles are capable of operating purely on battery power for short distances, but the primary energy consumption is liquid. These vehicles recharge their batteries during vehicle operation and do not have a plug-in feature to receive electricity from the electric grid.  However, they are often included in forecasts regarding electrified vehicles since these drivers are deemed likely to purchase an electric vehicle in the future. The three best-selling HEVs in 2019 included the Toyota RAV 4 Hybrid, Ford Fusion Hybrid and Toyota Prius Hybrid
  • Plug-In Hybrid Electric Vehicles (PHEV) – Plug-in hybrid electric vehicles feature two distinct powertrains – an electric drive system which receives power via plug-in feature directly from the electric grid and an internal combustion engine which derives power from liquid fuel. PHEVs are capable of running purely on electricity for 20 to 40 miles, after which time the vehicle relies upon the internal combustion engine and liquid fuel for power. Within the “electrified” vehicle market, PHEVs are most often associated with “electric” vehicles because they are able to draw electricity from the grid.  They are also often categorized as PEVs, or plug-in electric vehicles. The three best-selling PHEVs in 2019 were the Toyota Prius Plug-In Hybrid, the Honda Clarity Plug-In Hybrid and the Ford Fusion Plug-In Hybrid. 
  • Battery Electric Vehicles (BEV) – Battery electric vehicles refer to those vehicles which rely exclusively on power drawn from the electric grid via a plug-in feature. These vehicles are not equipped with an internal combustion engine and cannot rely upon liquid fuel for power. BEVs vary greatly in their overall range available from a fully charged battery, with some offering up to 90 miles of total range and others offering more than 350 miles.  BEVs are referred to as “electric” vehicles and also as PEVs. The three best-selling BEVs in 2019 included the Tesla Model 3, Tesla Model X and Chevrolet Bolt.

For more information on the types of electrified vehicles, visit the U.S. Department of Energy Alternative Fuels Data Center.

Types of Chargers and Charger Locations

Most analysts estimate that, for current drivers of PEVs, as much as 80% of their charging occasions occur either at home or at work. The balance is completed at destination or opportunity charging locations. However, as PEVs increase their share of the vehicle population, more drivers will reside where charging at home may not be a viable option (i.e., their homes do not have a secure garage or they live in a multi-unit dwelling without sufficient charging infrastructure).  Consequently, it is generally accepted that the availability of destination or opportunity charging locations will be critical to support the growing market for PEVs.

Understanding the differences between electric vehicle service equipment (EVSE) is important when considering the business case for offering charging services to these drivers. EVSE is broken down into three main classifications (more details are available from the U.S. Department of Energy): 

  • Level 1:  Level 1 charging is provided by a 120 V alternating current (AC) plug, similar to what would power a television or refrigerator.  This is the slowest means of delivering electricity to a PEV and typically delivers two and five miles of driving range per hour of connected charging.  Many PEV drivers rely on this type of service to charge their PEVs overnight in their personal garage.   There is no special equipment required to charge a PEV with a Level 1 outlet. 
  • Level 2: Level 2 charging is provided by a 240 V AC current in residential settings (such as the outlet for a home washer and dryer) or up to 280 V AC current in commercial settings.  Leve 2 charging can be accomplished by simply connecting a mobile charging cable into a NEMA 14-50 outlet (the same outlet as your washer and dryer) or by installing special equipment that will deliver a slightly faster charge to a PEV and can be installed for either residential or commercial use. Level 2 charging can deliver between 10 – 20 miles of range per hour of connected charging.  Level 2 chargers are often found within residences or multi-unit dwellings, places of work, destinations where drivers are expected to spend significant periods of time (i.e., shopping malls, movie theatres, restaurants, etc.). 
  • DC Fast:  DC Fast charging is provided by direct current charging equipment delivering up to 480 V of AC equivalent power.  This the fastest delivery of electricity to PEVs, with charging times ranging from 60 – 80 miles per 20 minutes of connected charging. (It is expected new charging equipment, when connected to capable vehicles, may deliver as much as 75 miles per 10 minutes of charging.)  DC Fast chargers are equipped with one of three distinct charging ports:  
    • CCS – Also known SAE J1772 combo, this configuration allows the PEV driver to use the same charging port when connecting to Level 1, Level 2 or DC Fast charging equipment.  Its maximum power output is 350 kW, which would enable delivery of 200 miles of range in 15 – 25 minutes of connected charge time.  Vehicle manufactures compatible with CCS include GM, Ford, VW, Audi, Porsche, BMW, Mercedes, Jaguar, Hyundai, Honda and Harley-Davidson.
    • CHAdeMO – CHAdeMO is primarily used by Japanese manufacturers of PEVs, including Nissan, Kia, Mitsubishi and Toyota. (Tesla vehicles can also use CHAdeMO chargers with a connector.) CHAdeMO chargers deliver a max power output of 100 kW, which would enable delivery of 200 miles of range in 35 - 70 minutes of connected charge time.
    • Tesla – Tesla vehicles and chargers are equipped with a unique charge port that can only be used by Tesla manufactured equipment. The Tesla superchargers are capable of delivering more than 250 kW and 200 miles of range in as little at 15 minutes. 

The rate at which a vehicle can charge when connected to specific charging equipment is a function of both the capacity of the charger as well as the design capabilities of the vehicle. Not all vehicles are equipped to receive a charge at 350 kW nor will all vehicles be able to receive the maximum miles per charge time as a charger is capable of delivering. PEVs and EVSE communicate with each other to ensure that the electricity delivered to a vehicle is appropriate for that vehicle’s configuration. In addition, to protect the vehicle’s battery from damage, maximum charging can only be delivered when the battery in between 20% and 80% state of charge. (State of charge refers to the level of charge of a battery system relative to its maximum charge capability.)

Cost of Electric Vehicle Service Equipment

The cost to install EVSE varies greatly and is influenced by a wide variety of factors. These include the number of chargers installed, the type of service (Level 2 or DC Fast) being provided, the maximum electricity delivery capacity of the chargers (150kW vs 350 kW), the proximity of the charger location to the incoming electricity supply, etc.  Providing a generic cost estimate is impossible due to the variety of factors influencing the ultimate cost. From discussions with professionals in the EVSE market, NACS has learned that a DC Fast charging system could be installed from as little as $30,000 if all that is needed is the charging equipment to as much as $500,000 if additional electricity service and site development is needed.

For an objective assessment of the associated costs and variabilities in EVSE installation, please refer to a recent report by the Rocky Mountain Institute, “Reducing EV Charging Infrastructure Costs” and analysis and case studies published by the U.S. Department of Energy.