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Electric Vehicle Charging Resources

Charging Station Locations

Many websites and smartphone apps provide charging locations, pricing, and availability, including:

  • The Electric Vehicle (EV) Charging Station Locations feature on the Department of Energy (DOE) website lists charging locations by geography, ownership type, charge levels, and payment systems.
  • PlugShare, a user-generated site that invites drivers to add locations and alerts other drivers when equipment is nonoperational.

Electric Vehicle Supply Equipment (EVSE) Resources

Washington resources

Federal resources

U.S. Department of Energy Alternative Fuels Data Center

Environmental Protection Agency (EPA) Energy Star

Federal Joint Office (U.S. Departments of Transportation and Energy)

Charging Forward: A Toolkit for Planning and Funding Rural Electric Mobility Infrastructure

General Services Administration

The General Services Administration (GSA) Blanket Purchase Agreement (BPA) is available to all government agencies authorized to lease or purchase vehicles from GSA Fleet. This includes most federal agencies but also many Native nations. You can use the agreement to procure a range of commercially available charging station options for level 1, 2, and DC fast charging, along with data subscription services.

EVSE purchasing resources include details about the BPA for EV charging equipment and integrating stations at your facility.

EV Charging Guides

Charging Speeds, Ports & Specifications

EV charging is categorized by charging speed and power levels, and alternating current (AC) versus direct current (DC). The power delivered by utility equipment through transformers to buildings is AC. The batteries in battery EVs store and deliver power as DC. AC power, common for moderate-powered charging, must be converted to DC using the vehicle’s onboard charger. DC fast charging (DCFC) equipment supplies DC power directly from the utility service to the vehicle batteries, bypassing the on-board charger.

Vehicle-to-Charger Ratios

Provided here are details to consider when planning to increase the number of vehicles that can share a single charging port. At first, it may be easiest to plan for one vehicle per EVSE port, but as facility staff gain experience with EVs, greater vehicle-to-port ratios will be more efficient.

These are the simplest EVSE. Fleets often use dedicated L2 units behind a fence where they control access, but these units may also be placed near an entrance where usage can be monitored.

  • Advantages:
    • Relatively simple to install.
    • Less expensive without network software and fees.
    • No need for Wi-Fi service or software upgrades.
  • Drawbacks:
    • Internal data about charger use must come from a separate meter or vehicle data tracking systems.
    • No electric load management so demand charges may kick in if lots of charging is initiated at once.
    • No automated communication to learn about outages and repairs.
    • Integrating telematics may be cumbersome.
  • Operation notes:
    • In-person technician repairs required
    • Creates the need for an outage notification and repair initiation process among staff.

  • Advantages:
    • Can be sized to meet unique charging needs of multiple vehicle types (light-, medium-, and heavy-duty).
    • Combine with load management systems for expansion without expensive upgrades.
    • Over the air remote software upgrades and technician trouble shooting.
  • Drawbacks:
    • Can be more expensive to install and operate (annual per-port software fees), and impact more parking spaces.
    • Costly demand charges could occur if charging times are not managed.
    • Additional costs for adding smart charging or third-party load management systems.
  • Operation notes:
    • Vehicle operators need to pick up the vehicle, disconnect the charging cable, return vehicle to stall when their shift is over, and reconnect the charger.
    • Works well when:
      • Facilities have a limited number of EVs and ample electrical capacity.
      • Shared charging is not possible.

Useful for municipal fleets with EVs that drive relatively few miles per day and charge overnight in shared parking stalls with access to L2 ports on a wall or pedestal. NEC 625 code allows for this type of charging on a continuous load but may require a technology solution or staff to plug vehicles in when one car reaches a full battery and the next vehicle needs to be charged.

  • Advantages:
    • Reduces initial investment costs.
    • Can leverage existing or limited electrical capacity.
    • With load management there is the potential to avoid or reduce peak demand charges.
  • Drawbacks:
    • Requires process management to ensure each vehicle and battery maintains sufficient charge.
    • Vehicles or the port must be moved and may increase operational costs and/or require a change in fleet driver behavior.
  • Operation notes:
    • Requires rotating vehicles between shared L2 ports or moving the charge cord between vehicles.
    • Makes sense when:
      • Fleet vehicles typically drive less than 50 miles a day and have dwell times greater than eight hours.
      • Staff manages charging by rotating charging cords or vehicles or directing drivers to charging when needed.

Charging Network Options & Load Management

The choice of non-networked or networked charging equipment typically balances the needs at each site with costs of equipment, software, and employee time. You can use telematics equipment attached to each vehicle or a networked charging system to adjust your charging schedule for your fleet’s specific needs.

Non-networked systems

Non-networked charging systems have one functionality—off or on. They don’t collect data about charging events or power usage. Non-networked equipment may be appropriate at smaller or remote charging sites, where there is no public access. For clean fuel crediting purposes, power use may be captured on a dedicated submeter.

Advantages: Simple, reliable, no software problems, no per-port network fees

Disadvantages: No data collection, no alerts sent about nonworking equipment

Networked systems

Networked charging can be very effective. If you do not have an application to capture fleet data, the network software offered on the EV charging equipment may offer adequate reporting and data capture for your fleet.

Advantages: Networked EVSE gather usage data so fleet managers can:

  • Understand and scale EV charging by identifying the number, time, and length of charges per day
  • Identify vehicles and the power delivered to each
  • Control access by determining if a user or vehicle is allowed to charge
  • Sophisticated systems can allow use by the public and collect fees
  • Allow remote control and troubleshooting of the charger

Disadvantages: Greater initial cost, networking fees, complaints about reliability:

  • The network may use Wi-Fi or cell services to communicate data to the cloud about the vehicle plug-in, kWh usage, time-of-use (TOU) charging, and other valuable data
  • Per-port cost for the software service and typically a five-year or annual fee, similar to the license fee for computer software

Read more in the BE Toolkit.

By balancing EV charging needs, managed charging reduces costs across the spectrum by:

  • Reducing or eliminating utility make-ready costs (transformer upgrades or bringing more power to a site).
  • Mitigating electrical service upgrades. For example, managed charging may reduce the need to increase panel amperage from 200 A to 400 A or 600 A, or for electrical panel upgrades (most commonly with smart breakers).
  • Reducing electricity costs by leveraging dynamic rates and reducing demand charges.

More utilities are designing rates to encourage EV charging when there is lower demand on the grid (off peak), such as overnight or when there is an excess of renewable energy. These rates reward customers with cheaper prices and help accommodate more renewable energy on the grid.

Estimate Power and Charging Station Needs

Estimate the power demands for your new EVs to identify the number and types of charging stations you will need for each location. Power demand is based on each vehicle’s duty- and drive-cycles and the levels of charging required. Consider future proofing: add battery storage capacity, solar, or battery back-up for resiliency

The Estimate Power & Charging Station Needs (PDF) addresses:

  • Factors that affect your charging needs
  •  Calculating energy needed to charge EVs Charging Load Profiles

EVSE Installation Best Practices

Determine preferred charging station locations & layouts

  • Identify preferred parking and EVSE installation locations in relation to an existing electrical panel, utility meter, or cabinet with transformer.
    • Keep in mind that back-in parking may affect access to the charging equipment.
    • Decide if the EVSE be mounted on a wall, pedestal, or other configuration.
  • Determine the proximity of charging stations to the electrical power service. Placing the charging equipment near an existing power supply will reduce cost, power loss, and time for installation. This is not always feasible and is highly dependent on the site.
  • Analyze duty cycles to determine the charging needs of the fleet.
  • For networked charging, ensure the location has adequate cell connection or Wi-Fi. This is typically only an issue in a parking garage or remote rural area. You may need to add a cell repeater to resolve this issue.
  • Identify operating issues, costs, fees, and department policies and chargebacks (for a shared facility) that may make a potential charging location ideal, mediocre, or unacceptable.

Assess power capacity

Complete a site walk-through and an electrical survey for each planned charging location and the entire facility to identify electrical service and upgrades required to support charging infrastructure.

  • Walk the site and facilities with a commercial electrician or other electrical professional.
  • Investigate selected electric panels, meters, or utility access points to determine electrical load available for charging station use.
  • Complete a load calculation for each panel and EVSE location. The electrical professional will work out the final load calculation and determine if unused or excess capacity is available for charging.
  • Adjust the location of EVSE charging stations to be closer to the best electrical panel locations.
  • Determine capacity required to add dedicated circuits for the planned EVSE.
  • If a facility has insufficient power, consider using managed charging and load management software to maximize load from the panel.

Additional considerations

  • Consider revenue models such as sharing charging stations with employees when they are not in use for the fleet or offering them for daytime public charging.
  • Familiarize yourself with planned new construction on site. Consider integrating EVSE work with new construction or electrical projects already planned.

Talk with Your Electric Utility

Contact your utility when you have preliminary plans for adding EVs and charging equipment to your facility. The utility may have an EV customer specialist who can address technical questions, confirm the new electrical usage estimates, or explain if they have programs or incentives to support fleet or workplace charging.

Questions to ask your utility

  • What is the time of use (TOU) rate structure, demand charges, or EV tariff in your territory?
  • Are there other fees and costs?
  • What are expected service upgrade costs?
  • Is a commercial customer education program available?
  • What are the costs and timing of utility shut-down during construction?
  • Do they offer a set fee for pre-paid or bundled utility or construction permits?
  • Will your utility:
    • Help minimize rates and fees?
    • Look for site features that require additional panel, transformer, electrical distribution line, or substation upgrades?
    • Address applicable building codes and permitting processes?
    • Discuss your installation plans and layout?
    • Provide insights about customer-side energy management, power sharing, operation, or ownership models that have worked at other public sites?
    • Identify capacity limitations at the location?