Dive Brief:

In a letter to fellow regulators and the public, Arizona Corporation Commission member Andy Tobin last week outlined how the commission will proceed in developing a new rule directing utilities to meet an 80% clean energy standard by 2050.

Tobin will file a draft version of the rule by July 5, to be discussed at the ACC's open meeting scheduled for July 19.

Tobin announced the plan in January, for utilities in the state to source the bulk of their electricity from renewables and nuclear within about three decades. Along with that, utilities will be directed to deploy 3,000 MW of energy storage by 2030.

Dive Insight:

The process to modernize the Renewable Energy Standard and Tariff, passed in 2006, is a lengthy one but may be in the home stretch. Tobin called his letter an "acknowledgement" of a process that began two years ago, and the beginning of a rulemaking proposal — which typically lasts six to nine months.

"These rules will lower energy costs for ratepayers and businesses around the state, protect our air, water, and forests, avoid costly stranded assets, ensure resiliency, promote economic growth, and establish Arizona as the leader in moving towards a clean energy future," he wrote in the June 22 letter.

Tobin's proposal, through a mechanism called the "Clean Peak Standard," would require utilities to deliver an increasing portion of their renewable energy during peak electricity demand hours, incentivizing storage deployment. According to his letter, the new proposed rules will "lower energy costs for ratepayers and businesses around the state, protect our air, water, and forests, [and] avoid costly stranded assets."

That proposal comes as the state's investor-owned utilities have already met Arizona's 15% renewable energy mandate, and are looking to natural gas. Arizona Public Service is considering 5.3 GW of gas generation by 2030, more than doubling its current capacity. And Tucson Electric Power's plan includes nearly 360 MW of new gas by 2032, a 30% increase in gas capacity.