RTF analysts developed estimates of per unit technical potential for demand response for Connected level 2 Electric Vehicle (EV) Chargers. Connected level 2 chargers may reduce charging output power in response to a DR signal with a typical range of ~3-7kW per unit maximum Demand Response potential during steady state charging. Chargers can be throttled between 100%-0% output power. Chargers currently predominantly communicate via Wi-Fi or cellular service.
The primary components influencing this per unit potential are the vehicle itself, specifically the vehicle maximum power acceptance (kW), above which the vehicle will not accept a higher rate of charge. Potential impact is also affected by the charger's maximum output capacity (kW), the typical range of residential level 2 AC 240V charger output power is 3-7 kW, and finally by the charger throttled output capacity (%). A charger's throttled output capacity will reduce the per unit DR potential below 100% of 3-7kW.
Data sources used for this analysis include publicly available regional electric vehicle registration and vehicle maximum power acceptance datasets paired with literature reviews of electric vehicle charger studies, and interviews with electric vehicle charger subject matter experts and programs.
The per unit potential is calculated with the following governing equation:
Residential Level 2 AC Charger Per Unit DR Potential=Steady State Charger Output Capacity (kW)*Charger Throttled Output Capacity (%)
Level 2 EV Charger DR Workbook RTF Presentation DR Subcommittee Presentation DR Subcommittee Notes