Arizona Public Service Co. (APS) recently issued two requests for proposals (RFPs) — one to acquire both renewable energy and additional peaking capacity resources, and the other to install more battery energy storage at two existing APS solar plants. The APS also recently executed an agreement with Invenergy to add battery energy storage to six APS solar plants located in Maricopa County and Yuma County.
The plans to pair storage with solar through this new RFP and the work with Invenergy were part of a suite of clean energy projects that the APS announced last year. The addition of this technology will extend the benefits of "solar after sunset," when customers' summer energy needs remain at peak levels. These ambitious storage plans were followed by a clean energy commitment made earlier this year that set the APS on a path to achieve a carbon-free power mix by 2050.
"We have made steady progress since setting our clean energy goal in January," said Brad Albert, APS vice president of resource management. "Moving ahead with our energy storage plans, our recent purchase of more clean wind generation, and our expanded voluntary energy conservation program all support meeting the needs of our growing customer base with reliable, affordable, and increasingly cleaner resources."
All Source RFP
The APS requests renewable energy resources of approximately 300 MW to 400 MW per year which will increase the amount of clean energy on the APS system. The RFP is also designed to address peak capacity needs of about 200 MW to 300 MW per year to maintain reliable electric service for customers during times of highest energy usage. Procuring more renewable energy supports an interim target within the APS' clean energy commitment — to have 45% of its generation portfolio in renewables by 2030. This RFP is open to all technologies, including supply side and non-supply side resources. Proposed projects must have in-service dates in either 2023 or 2024.
Battery Energy Storage RFP
The APS requests a combined total of 60 MW of battery storage additions to two of its existing AZ Sun Project solar facilities — the Red Rock and Chino Valley plants located in Pinal County and Yavapai County, respectively. Proposed projects must begin delivery no later than June 1, 2023.
The RFP process will be monitored and reviewed by a third-party independent monitor. The All Source RFP, Battery Energy Storage RFP, and important information about proposal requirements and respondent registration are available here.
Added Battery Capacity to Arizona Sun Sites
Battery energy storage systems will be developed and installed by Invenergy at six of the APS' existing large-scale solar power plants and will begin operation in early 2022. Since announcing these plans last year, the APS has now executed the agreement after working with Invenergy to incorporate enhanced safety standards in battery energy storage.
