Selection and Placement of PEV Chargers

Charger Requirements

The purpose of the charging equipment is to get electricity into the car from the electricity grid. Thus, in addition to the charging equipment itself, installation requires running an electrical supply line between the appropriate electrical panel and the charging station, mounting the charging station on either an existing wall or on a ground-mounted pedestal, and providing network connectivity for the charging station, if required or desired.

The placement of an EV charger is dependent on a number of factors. How you weigh the various factors depends on how you plan to use the charger. 

Selecting a Charger Type

Most municipalities will select Level 2 chargers to charge their electric vehicle(s) (see How do I Charge a PEV?). Level 2 chargers provide plenty of power to charge passenger vehicles for a municipal fleet. Some fleets may even be able to use Level 1 chargers, particularly if vehicle usage is expected never to exceed 30 to 40 miles per day or if the vehicle is a PHEV (see EVs 101 — Introduction to Electric Vehicles).

Level 2 chargers generally provide two charging ports for each charger, allowing one charging station to serve two vehicles. Some municipalities may wish to save money and simply use either a Level 1 charger, or provide an outlet to plug in the charging device that comes with the vehicle. In either case, please note that once a charging station is supplied with electricity and placed amount, it is relatively simple and inexpensive to change the actual charging device. That is, if you start with an outlet on a pedestal to supply electricity for the vehicle-supplied Level 1 charger, it is relatively simple to change that out for a Level 2 charger, assuming that your initial installation permits the larger electrical wiring required for a Level 2 charger to be pulled through to replace the Level 1 wiring, and your panel has the capacity to supply the Level 2 charger.

Note that the US EPA’s ENERGY STAR program certifies electric vehicle charging equipment based on energy efficiency. Information can be found at: https://www.energystar.gov/products/other/evse/partners

Number of Chargers

In general, it is a good idea to have a single charging point available for each of your fleet vehicles. This will allow all vehicles to be charged overnight. Some EV fleet managers choose to have more vehicles than chargers, as generally a fully charged EV will have enough range to be used several days between charges. However, this requires additional management to assure that is the case.

Note that if you are considering increasing the number of electric vehicles in your fleet at any time over the next decade, you may wish to install additional electrical conduit and panel capacity at the outset. The marginal cost of doing so is relatively low, and will provide you with significant flexibility moving forward.  You may also wish to assure that the conduit you install will be able to handle Level 2 charging.

Selecting the Electrical Panel for the Chargers

Electric vehicles use about 7000 W when connected to a Level 2 charger, and about 1400 W when connected to a Level 1 charger. 7000 W is about the amount of electricity used by an electric stove with all four burners and oven on. 1400 W is about the amount of electricity used by powerful hairdryer. Thus, the electrical load added to the building when charging electric vehicles is not insignificant, and may affect the demand charges on your electric bill, particularly if the meter to which the electric vehicle charging equipment is connected has relatively few other loads.

Distance from the Electrical Panel

The greater the distance between the PEV charger and the electrical panel to which it will be connected, the more expensive the installation. This is particularly true if the installation requires the electrical cable to be placed underground. This cost of trenching, particularly if pavement needs to be removed and replaced, can be significant. This should be taken into account when siting EV chargers. There may be no need to have them installed near a door or in a prominent spot, particularly if that will add significant cost.

In-Ground or Wall-Mounted

PEV chargers may be mounted directly on a wall or on a pedestal installed in the ground. Generally, it is much less expensive to attach a charger to a wall than to install it in the ground, particularly if installing it on a wall can keep all the electrical supply lines inside, and installing it on a pedestal would require burying the electrical wires. If it is required that the charger be mounted on a pedestal, it will be less expensive to install it in a location that will require the least disruption of pavement. Thus, placing it at the edge of a lot in a grassed area may be a good option. Again, as noted above, it is generally a good idea to provided extra electrical conduit to allow for anticipated or potential additional charging stations.

Inside or Outside the Fence

If you are planning to use a PEV charger for a fleet, you may have the option of placing it on the private side of the fence rather than the public side. This may help protect the charger from tampering and prevent unauthorized persons from using it. In addition, if you are providing it in a facility that has both paid and unpaid parking available, you may choose to place it in the paid or unpaid side.

Networked or Not Networked

Charging equipment can be equipped with communications hardware and software that will allow charging to be remotely monitored. This can be useful for fleet managers to track whether and how frequently PEVs are being charged.  It is also needed if the municipality wishes to have the charger equipped to accept credit cards or other payment devices. 

Note that networked connected chargers have a higher initial cost than do non-networked chargers. In addition, there is a cost for a vendor to provide the ongoing communications service. Some municipalities have found that the annual cost for the communications service was greater than the benefit they received. This may be particularly true for small deployment of one or two vehicles.

Public vs Employee vs Fleet Parking

A charger provided for public use rather than employee parking or fleet use may have different considerations for placement. Many organizations prefer to place visitors/guest parking closer to the door than employee parking. Depending on facility layout, the area nearest the electrical panel may be more acceptable for employee parking than for visitors/guest parking. Also, if the charger is for charging a vehicle in the municipal fleet, rather than a privately owned employee vehicle, the considerations may also change. An organization may wish to promote their ownership of an electric vehicle in their fleet, and may wish to do that by placing the charger in an area where it can easily be seen by the public.

For Additional Information

As noted, there are various, sometimes conflicting, factors to weigh in determining charger type and placement. DVRPC suggests that municipalities consult an expert in electric vehicle deployment for additional information. This expert should generally not be a vendor of charging equipment, who would have an inherent conflict of interest. A good resource to start with is your local US Department of Energy Clean Cities’ representative or the state resources listed in the For Assistance section.

Robert GraffManager, Office of Energy and Climate Change Initiatives