Howard Fischer/Capitol Media Services

Former state utility regulator Kris Mayes details July 5, 2018, why she believes voters should support requiring electric companies to produce half their power from renewable sources by 2030.

Renewable-energy advocates dropped off over 480,000 signatures Thursday in hopes of requiring Arizona’s electric utilities to acquire at least half of their power from solar, wind, biomass and other renewable sources by 2030.

A challenge to the initiative is expected from the group called Arizonans for Affordable Energy, which is being funded by the parent company of APS. The group is arguing that if enough solar energy is produced, the future of the Palo Verde Nuclear Plant could be in jeopardy.

Kris Mayes is a former member of the Arizona Corporation Commission and is part of the group Clean Energy for a Healthy Arizona, the backers of the measure. She said the opposing group's argument on Palo Verde is false.

"Unfortunately, APS is out spreading what is essentially an outright lie," Mayes said, "which is that this initiative would endanger Palo Verde. It will not."

Mayes said that while some say nuclear energy could be an energy alternative, because it’s not a pollutant, she said it’s not renewable and is more expensive than other forms of renewable energy.