For more information on measuring and reporting ZEV charging at the building-level for federal facilities, refer to the Best Practices for Measuring and Reporting Electricity From Electric Vehicle Charging Stations at Federal Facilities.
Federal agencies are responsible for the accurate measurement and reporting of electricity used in government zero-emission vehicles (ZEVs), including battery electric vehicles (BEV), plug in hybrid electric vehicles (PHEV), and low-speed electric vehicles (LSEV). The U.S. Department of Energy’s Federal Energy Management Program (DOE FEMP) offers best practice options for measuring ZEV electricity use at agency facilities and off-site locations. These are best practices for vehicle-level fuel reporting in the Federal Automotive Statistical Tool (FAST).
Required Fueling Data for FAST Reporting
The following vehicle-level data is required for the annual FAST submission to complete the fueling data submission for federal fleet vehicles, including ZEVs:
- Vehicle identification – to assign charging events to a vehicle.
- Date – to determine the fiscal year (FY) of the fueling event.
- Location – to separate out the amount of fuel added to the vehicle and the cost of the fueling event by state.
- Fuel/type volume – to report the estimated fuel consumption of the vehicle. For a BEV this includes just the electricity in kilowatt-hours consumed by the vehicle and for a PHEV this includes both the electricity in kilowatt-hours and number of gallons for any other fuel sources (e.g., gasoline) consumed by the vehicle.
- Fuel cost – to report on the cost of the fueling event for vehicles where the cost of fueling is not covered in the vehicle’s monthly lease (e.g., agency-owned vehicles).
While not required, it is recommended that fleets track data, including charging and fueling information, through their Fleet Management Information System (FMIS) throughout the year and not just look at their vehicle-level data at the end of the FY. Effective fleet management needs reasonably complete, current, and accurate information about the vehicles and their operation throughout the year.
Best Practice: Use Vehicle Telematics Data
Vehicle telematics provide the best practice for measuring ZEV electricity consumption on a vehicle-level. ZEVs with telematics devices installed provide simple and accurate reporting of electricity fueling for both BEVs and PHEVs.
Fleet vehicles that have a telematics device installed are capable of tracking vehicle charging data. Telematics track charging sessions for a vehicle, including the date, location, charging time, the beginning and ending state of charge, and total kilowatt-hours added during the session (referred to as Energy Added in Geotab’s EV charging report, for example). This provides simple and accurate reporting of the total electricity consumption of the ZEV during the previous FY.
For charging sessions completed at an EV charging station that requires payment and where the costs are not covered under the vehicle’s monthly lease, the cost of the charging session is required to be tracked and reported on in FAST for each vehicle and in each state where charging occurred. It is recommended that a receipt or log of these costs be kept and stored in the FMIS to track charging costs throughout the FY.
Use this method if the ZEV:
- Has a telematics device installed
- Charging session cost from public EV charging sessions is tracked by the driver and shared with the fleet team.
| Note: If the fleet vehicle was in use during the FY prior to installing the telematics device, one of the methods below would need to be used in combination with this method to track kilowatt-hour used for the time before the telematics device was installed. |
While a telematics device can be installed on a LSEV, they are not able to measure and report charging session data for that type of vehicle. One of the alternative options below should be utilized to report annual electricity use for LSEVs.
Alternative Option 1: Summing Charging Transactions From Charging Stations
When a fleet vehicle lacks a telematics device, an alternative option involves tracking electricity usage through the networked EV charging station. This method applies to charging sessions completed on-site, at public charging sessions, or at an employee's home (for home-to-work authorized vehicles).
A networked EV charging station has built-in data management or metering capabilities that track EV electricity use. Charging session data for individual vehicles can be tracked by requiring fleet drivers to use a phone app, an access key (e.g., a General Services Administration (GSA) provided RFID token), or a designated fueling card tied to the vehicle (e.g., WEX). The data is then sent to a remote system, such as a cloud server, via a cellular connection. To report in FAST, the EV charging transactions from networked EV charging stations for each fleet vehicle can be summed for the FY.
- Agency-owned/controlled networked EV charging station events: Program managers have access to the dashboard to track historical charging session data, including total kilowatt-hours added during the session. Typically, there is an annual fee for operating a networked EV charging station.
- Public charging events: When the charging session is paid for using the ChargePoint RFID token provided by GSA or the WEX fueling card, the transaction details are made available on the GSAFleet.gov fueling report. For agency-owned or commercially leased ZEVs, confirm with the fueling card provider that the transaction details for charging sessions (vehicle identification, date, location, total kilowatt-hours added during the session, and cost) are provided as needed for reporting purposes. Receipts may be required to track the charging data.
| Note: If the ZEV uses a non-networked EV charging station (either agency-owned or public) for charging events during the FY, this option alone is not suitable, and an alternative tracking and reporting method should be used to track electricity added for charging sessions at non-networked EV charging stations. For a vehicle without a telematics device and charging at a non-networked EV charging station, Alternative Option 2 or 3 below should be used to estimate the electricity added in addition to the electricity tracked for charging events at a networked EV charging station. |
Use this method if the ZEV:
- Does not have a telematics device installed
- Completes charging sessions at an on-site networked EV charging station
- Charging session data is tracked by the driver and shared with the fleet team.
Alternative Option 2: Track Electricity Use From Vehicle’s On-Board Computer
Some ZEVs record and share charging session data on the vehicle’s on-board computer which can be accessed from the dashboard screen. Depending on the vehicle, multiple charging sessions may be stored or just the most recent charging session. For this option, it is recommended that fleets create a log for drivers to record the charging session data (vehicle identification, date, location, total kilowatt-hours added during the session, and cost). If using this method, it is recommended that the charging session data be uploaded to the FMIS on a regular basis (e.g., automatically through an electronic log or uploaded monthly for a manual log) so fleets can track the electricity consumption for ZEVs.
Use this method if the ZEV:
- Does not have a telematics device installed
- Uses a non-networked EV charging station for charging
- Has the ability to display the electricity added (kilowatt-hours) from the previous charging session data
- Charging session data at off-site or non-networked EV charging station is tracked by the driver and shared with the fleet team
- Fleets have a process for drivers to log charging session data.
Alternative Option 3: Estimate Using Measurement and Verification Standards
If none of the above methods are suitable for tracking vehicle-level energy use, then electricity consumption may be monitored using methods and procedures consistent with FEMP’s energy measurement and verification (M&V) guidelines. This includes use of vehicle mileage in conjunction with a calibrated vendor-provided vehicle efficiency factor to calculate consumption. For example, the 2023 Nissan Leaf base model, a BEV available from GSA, has a vehicle efficiency factor (provided by the U.S. Environmental Protection Agency) of 30 kilowatt-hours per 100 miles (see fueleconomy.gov). Therefore, the estimated electricity consumed during an annual use of 12,000 miles would be 3,600 kilowatt-hours.
In addition to tracking total electricity consumed, total electricity added by state is also required for FAST reporting. If the vehicle operates in more than one state, when charged at a non-networked EV charging station the driver will need to log basic information for each charging event, such as vehicle identification, date, location, state of charge at the start and end of the charging session, and odometer reading at the start of each charging session. This information can then be used to estimate the electricity added to the vehicle in each state for reporting purposes.
Use this method if the ZEV:
- Does not have a telematics device installed
- Uses a non-networked EV charging station for charging
- Does not track electricity added from charging session on the on-board computer.