Dive Brief:

• California will need between 229,000 and 279,000 electric vehicle chargers in public locations and multi-unit dwellings by 2025 to meet Gov. Jerry Brown's (D) goals of having 5 million zero-emission vehicles on the road by 2030, according a new report from the California Energy Commission.
• The conservative scenario in CEC report estimates the state will need at least 99,000 workplace and public level 2 (L2) chargers by 2025 to meet the goal, as well as 9,000 DC fast chargers. Under a higher estimate scenario, the state will need more than 133,000 L2 chargers and nearly 25,000 DC fast chargers, and the state will also need 121,000 EV chargers at multi-unit dwellings under both scenarios. 
• The report also outlines expected load impacts of EV growth, dubbed the "Dragon Curve," which include a bump in workplace charging demand during weekday mornings and a steep ramp up in evening power demand due to residential charging. All told, EV chargers could add 1 GW of peak demand to the grid, authors wrote. 

Dive Insight:

The CEC's new report, written with the National Renewable Energy Laboratory (NREL), forms the foundation for implementing Gov. Brown's January executive order, which called for $2.5 billion in revenues from the state's carbon cap-and-trade program to be directed to EV charger deployment. 

The report, released March 16, analyzes expected EV growth, charging behavior and location to devise two sets of estimates for charger necessity, a low and high scenario:

Differences between the scenarios are largely due to expected impacts on electricity demand from EV charging, report authors wrote.

"Charging locations that experience a sharp increase in demand within a brief time frame, like workplaces, will have a smaller range in between the high and low estimates of chargers demanded," they wrote. 

Additionally, the behavior of EV owners in a certain county also influenced the expected need for chargers. 

"For example," authors wrote, "if a county’s travel is predominantly associated with commutes to and from work, the peak demand associated with those charging behaviors will manifest themselves in a relatively small variation in total chargers needed."

The CEC report also details expected impacts of EV charging on power demand. During weekdays, authors estimate an increase in workplace charging in the mornings, followed by a steep ramp up in residential charging demand once residents return home. On weekends, the workplace bump is removed, but in both scenarios the presence of DC fast charging creates a bumpy load profile that could increase the need for plant ramping or load management — a phenomenon researchers have labeled the "Dragon Curve."

Taken together, demand from residential and nonresidential EV chargers could amount to more than 1 GW by 2025, the report estimates, causing "significant impacts at the local level" that should be the target of future analyses.

In particular, authors stress that the increase in DC fast charging should be "managed with appropriate electrical service and distributed generation and storage resources to effectively prevent system overloading and to avoid utility peak demand charges."

Shifting EV charging load to better align with the delivery of solar resources at midday could also help utilities better integrate chargers onto their systems, authors wrote, but the ability to do that will "depend on the use of charging technologies and price incentives that aid dispatch ability and avoid substantive changes to driver travel and behaviors."

Factors that can enable that EV demand shifting include improving residential chargers to "permit shifting demand to the early morning," and the use of chargers in nonresidential areas to "reduce the need for additional grid ramping capacity and operational costs associated with the charging scenario examined."

"Networking technologies that enable shared use should be leveraged to automate demand responsive charging," authors wrote.