The U.S. Department of Energy's evaluation of the 2011 EV Project.
Nationwide, United States
Considerations for Corridor and Community DC Fast Charging Complex System Design
Summary Information
Since the introduction of publicly accessible direct current fast charging (DCFC) systems during the EV Project in 2011, the U.S. Department of Energy and others have conducted surveys on deployment and use of DCFC equipment. The EV project deployed over 100 DCFC that used the CHAdeMO charging standard, which was included on all participating Nissan Leaf vehicles, adopted by Japanese automakers. The EV project installed DCFC in eight states in both metropolitan areas and along transportation corridors in rural areas.
Lessons Learned
Owners of EV charging stations can choose to charge customers by kWh, by the hour, per session, or some combination thereof. Billing for the electricity consumed (by kWh) seems intuitive, but does not incentivize drivers to unplug once the vehicle is fully charged and regulations in some states prohibit sales of electricity by entities that are not electric utilities and this strategy does not incentivize the driver to unplug after their vehicle is fully charged.
Where allowed by law, a charging site host may consider a hybrid strategy, where the consumer pays for the electricity consumed and then time spent plugged in once the vehicle is finished charging.