News Release

Arizona Energy Regulators Approve Solar Daytime Charging Program for Electric Vehicles

PHOENIX - Chairwoman Lea Márquez Peterson of the Arizona Corporation Commission (“Commission”), along with her fellow commissioners, approved a new Electric Vehicle (“EV”) Charging Tariff for Arizona Public Service Company (“APS”) that incentivizes EV charging during the day, when solar energy production is the highest.

The new Solar EV tariff establishes a new “off peak” period for commercial customers from 9am to 3pm (when solar energy production is the highest) and a new “on-peak” period for the remainder of the day (when electric generation can be the most expensive).

Under the new Solar EV tariff, EV owners can receive discounts as high as $0.04223 per kWh if they charge their EVs at commercial establishments during the new “off peak” hours.

“Programs like this are vital to ensuring that our utilities can support the growing adoption of electric vehicles with renewable solar energy,” said Chairwoman Márquez Peterson.

“This provides an incentive for businesses, retail locations, and commercial establishments to add an additional amenity that can help to attract new customers and provide a benefit to employees. By encouraging businesses to install charging stations, the program can make it easier and more affordable for employers to offer workplace charging, while making it more cost effective to attract new customers to commercial establishments.”

The new Solar EV tariff is similar to another program, which is offered to residential customers and incentivizes electric vehicle owners to charge during ‘off-peak’ hours late at night

“While it's convenient for electric vehicle owners to charge late at night,” said Chairwoman Márquez Peterson, “There is no solar at night. It is common sense to charge during the day when solar is most abundant.”

Thus, the new Solar EV tariff for businesses provides an incentive that complements the existing EV charging rate for residential customers at home: EV owners can take advantage of the low charging rate at night from the comfort of their own home, while during the day they can take advantage of the low charging rate at commercial establishments or at their place of work.

“By pairing the charging of electric vehicles with the hours of maximum solar production on the grid, this program can help to support the adoption of electric vehicles in a way that can also benefit the electric grid.”

Chairwoman Márquez Peterson first proposed the Solar EV program in October 2021, when APS’s rates were under review by the Commission. The Commission voted 4-1 to support the proposal due to its promise to provide incentives to charge EVs at business locations during the day, when solar energy is most abundant.

Chairwoman Márquez Peterson and her fellow commissioners demonstrated continued support for the program with their final vote approving the tariff this year. “Not only are we supporting solar energy with programs like this, but we are also benefiting the grid through shifting energy use to the times of day that we have abundant and inexpensive solar energy.”

One of additional benefits of the new Solar EV tariff is the ability to increase electric load during the times of day when power generation is least expensive and thereby shift energy usage away from “peak” hours that are most expensive.

This “load building” helps to “even out” the amount of electricity that must be generated throughout the day and helps to decrease the total cost to electric utilities, which is ultimately passed onto customers as savings.

“During certain times of the year, there is more solar power on the grid than we need. Programs like this help to take advantage of that cheap and sometimes free solar energy that is generated here or in other states.”

“I believe that electric vehicle technology is something to pay close attention to in the evolution of our Arizona electric regulation. I am excited to see what the new generation of electric vehicles can do to help all Arizona families cut costs and help our electric grid at the same time.”

Business owners and facilities managers interested in taking advantage of the new program should contact APS here.

To review APS’s new Rate Rider GS-EV and other rate riders, click here.

To learn more about APS’s current EV programs visit

Arizona Corporation Commission

1200 W. Washington Street

Phoenix, AZ 85007


Corporations Division

1300 W. Washington Street

Phoenix, AZ 85007


Tucson Office (Walk-ins only)

400 W. Congress Street

Tucson, AZ 85701