6 Notes

6.1 Sources

6.1.1 Alternative fuel stations

The data set includes electric charging stations that are currently active (excluding planned or temporarily unavailable). I downloaded data sets for the last day of each year 2016-2025 from https://afdc.energy.gov/data_download on 2026-01-18 and 2026-01-19 and combined them.

Dataset: Alternative fuel stations
Fuel Type: Electric
Timeframe: Past
Historical Type: Single day
Fuel Type: Electric
Station Access: All
Station Status: Open
Country: United States
Date: 12/31/YYYY
File Format: CSV

Data dictionary: https://afdc.energy.gov/data_download/historical_stations_format

There are some pre-built plots and summaries (which I did not use). See https://afdc.energy.gov/data/categories/alternative-fueling-stations

There is a developer API (which I did not use): https://developer.nrel.gov/docs/transportation/alt-fuel-stations-v1/

Alternative Fuel Stations Query our database of alternative fuel stations. This dataset powers the Alternative Fueling Station Locator on the Alternative Fuels Data Center. This includes biodiesel, compressed natural gas, ethanol, electric charging, hydrogen, liquefied natural gas, and propane station locations.

6.1.2 At-home charging

NREL “County Electric Vehicle Home Charging Access Shares” https://data.nrel.gov/submissions/278

County Electric Vehicle Home Charging Access Shares from the 2030 National Charging Network Study This file contains modeled county-level home electric vehicle (EV) charging access shares from the study, “The 2030 National Charging Network: Estimating U.S. Light-Duty Demand for Electric Vehicle Charging Infrastructure” by Wood et al. (2023). These are based on modeling in “There’s No Place Like Home: Residential Parking, Electrical Access, and Implications for the Future of Electric Vehicle Charging Infrastructure” by Ge et al. (2021).

Wood, Eric, et al. 2023. The 2030 National Charging Network: Estimating U.S. Light-Duty Demand for Electric Vehicle Charging Infrastructure. Golden, CO: National Renewable Energy Laboratory. NREP/TP-5400-85654. https://www.nrel.gov/docs/fy23osti/85654.pdf.

Ge, Yanbo, et al. 2021. There’s No Place Like Home: Residential Parking, Electrical Access, and Implications for the Future of Electric Vehicle Charging Infrastructure. Golden, CO: National Renewable Energy Laboratory. NREL/TP-5400-81065. https://www.nrel.gov/docs/fy22osti/81065.pdf.

Downloaded https://data.nrel.gov/system/files/278/1734741167-NREL_county_EV_home_charging_access.xlsx on 2026-01-23. File dated “12-20-2024 17:32:47”

Converted tables on pages 54-56 of the PDF in Wood (2023) to csv files:

2030-private-network-sim.csv
2030-public-l2-network-sim.csv
2030-public-dc-network-sim.csv

6.2 Possible future exploration

EV vehicle registrations by state YE2023 https://afdc.energy.gov/files/u/data/data_source/10962/10962-ev-registration-counts-by-state_9-06-24.xlsx?12518e7893 downloaded 2026-02-21.
- Data Source: Vehicle registration counts derived by the National Renewable Energy Laboratory with data from Experian Information Solutions.
Baek (2024): A dataset for multi-faceted analysis of electric vehicle charging transactions
Horesh (2024): Comparing costs and climate impacts of various electric vehicle charging systems across the United States

6.3 Issues

TODO: Why is there a systematic drop in chargers between 2020 and 2021 (Figure 1.5)? I downloaded 2016-2019 so I have 10 years of data, which confimrm it’s a one-time issue: A change in data standards? Reporting policy? Recategorization?
- DONE: Why does Tesla’s count in Figure 2.2 drop after 2017? A: “Tesla Destination” became a separate ev_network value starting in 2018. No action required.
DONE: Why are there so many stations 2016-2018 with ev_network = NA? A: It seems the “Non-Networked” category wasn’t introduced until after that. Converting the NAs to “Non-networked” makes the “Non-networked” plots credible back to 2016.
DONE: (These are in addition to chargers listed in other columns). Some station records do not include a count of number of chargers, or they list something in ev_other_info. How can I make use of this info? And what are “inductive” and “conductive” chargers? Most comments mention one or the other (usually “inductive”).
- According to the data dictionary https://afdc.energy.gov/data_download/historical_stations_format :
  
  For electric stations, the number and type of additional EVSE ports, such as: SP Inductive - Small paddle inductive LP Inductive - Large paddle inductive Avcon Conductive
DONE: Why are there two Tesla ev_network values? A: “Tesla Destination” is the slower Level 2 chargers. “Tesla” is the supercharger network. https://ev-chargers.com/news/tesla-supercharger-vs-destination-charger/
DONE: SeemaCharge acquired by Blink in 2022: https://blinkcharging.com/blog/semaconnect-welcome-to-blink-charging . I converted all to Blink.
DONE-ISH: Shell’s business strategy has been changing, and it’s hard to discern how pre/post ownership stations and chargers are categorized in all years.
- Recharge ended third-party app charging in 2025: https://swtchenergy.com/blog/news/what-you-need-to-know-about-the-shell-recharge-shutdown-how-swtch-can-help/
- Are there implications for my analysis? Probably not, since operators presumably moved to another software management provider.
- Q: Where is the Shell Recharge data in Figure 2.2 prior to 2022? A: Unknown.
DONE: Why is Volta data missing after 2023? It was acquired by Shell in 2023. Are these included in Shell Recharge, where data starts in 2022? No it doesn’t seem so.
- Shell announced in 2025 it will shut down Volta, Shell’s remote charging network, in favor of fast chargers at Shell stations. https://www.electrive.com/2025/08/08/shell-to-dismantle-volta-charging-sites-in-the-us/. But at the beginning of 2026 Jolt announced they will acquire a “substantial portion” of the Volta network and thereby enter the US market https://evchargingstations.com/chargingnews/jolt-enters-the-us-market/