Arizona Public Service (APS) is soliciting proposals for energy projects providing up to 1,500 MW to help meet the utility’s reliability and clean energy goals.

The 1,500 MW of new resources will include up to 800 MW of renewable energy. APS issued the request for proposals in May and applications are due July 8.

Arizona’s summers are getting hotter while the state’s population and economy are growing rapidly, increasing the demand for electricity, the company said.

In addition, APS made a commitment to provide 100% carbon-free electricity by 2050, with an interim goal of 65% clean energy and 45% renewable energy by 2030. APS’s current energy mix is 50% clean.

“This broad market solicitation will help APS exit from coal-fired generation by 2031 and maintain adequate power supply to serve customers,” APS said in a release.

The company’s clean energy transition is “anchored by the Palo Verde Generating Station’s carbon–free nuclear power,” APS said in a clean energy report. Palo Verde is the largest nuclear plant in the U.S., with a capacity of 3,990 MW.

Storage Projects Welcome

APS is accepting applications for projects such as solar, wind, biomass, geothermal, landfill gas or storage, as well as combination projects such as solar plus storage.

In its request for proposals, APS said it would accept proposals providing at least 5 MW per site, but that it prefers projects larger than 200 MW.

The utility is looking for projects that will be in service starting in 2025 or 2026. Proposals will be accepted for projects being completed in phases, starting as soon as Dec. 1, 2024, and as late as Dec. 31, 2026.

According to the RFP, the resources may be offered through a power purchase agreement, a build-transfer agreement or a load management agreement. Examples of load management projects include behind-the-meter demand response programs or energy efficiency programs.

APS is seeking projects that would interconnect directly to the utility’s transmission system.

For renewable resources, APS said it would prefer projects that maximize the amount of energy generated and delivered from June through September and between 3 p.m. and 9 p.m. For energy efficiency proposals, APS would prefer projects that reduce demand during those same periods.

For storage projects, APS said it would prefer a project that can deliver the full proposed capacity for more than four consecutive hours.

“In addition, clean, flexible, dispatchable resources are increasingly important in helping APS meet its clean energy goals [and] maintain system reliability, and will be valued accordingly,” the RFP said.

Clean Energy Additions

The new resources that APS acquires from this year’s request for proposals will be in addition to 1 GW of clean energy secured through an all-source RFP and separate battery energy storage solicitation issued in 2020.

Those new resources, which will be in service by 2024, include 425 MW of solar power nameplate capacity, 238 MW of wind power nameplate capacity and 635 MW of battery storage nameplate capacity.

The Resource Planning Advisory Council, an APS stakeholder group, helped design the RFP. The group includes representatives of environmental groups, public interest organizations and universities, as well as consumer advocates.

In addition, an independent third party is monitoring the RFP process.

For this year’s RFP, APS plans to notify short-list applicants in August and make a final selection in September.