AriSEIA submitted Exceptions to the Recommended Opinion and Order (ROO) to address several findings and conclusions that are not supported by the evidentiary record, are inconsistent with Commission practice, or undermine regulatory certainty. The ROO adopts Sulphur Springs Valley Electric Cooperative, Inc.’s (SSVEC’s) cost-of-service study despite its omission of recognized distributed generation benefits, eliminates commercial net metering without a fair transition period, removes the ten-year export rate lock even though the Commission recently confirmed that it should remain unchanged, and concludes that SSVEC did not underpay distributed generation members in 2023 despite the Cooperative paying below avoided cost and failing to update its export rate as required. It further approves interconnection fees that are unsupported by the record, declines to direct SSVEC to evaluate virtual power plant and critical peak pricing programs despite consistent support for such programs across multiple Arizona utilities, and dismisses the legitimate transparency concerns raised by the settlement process.

For these reasons, and for those set forth in detail in the filing, AriSEIA respectfully requested that the Commission modify the ROO. AriSEIA submitted proposed amendments addressing the phase-in period for commercial net metering, the ten-year export rate lock, reimbursement of the 2023 underpayment, the interconnection fee provisions, and the virtual power plant and critical peak pricing directive.

Arizona Corporation Commission
1200 W. Washington Street
Phoenix, AZ 85007
 
Re: AriSEIA Support for the 2024 Arizona Public Service Company Demand Side Management Implementation Plan, Docket No. E-01345A-23-0088
 
Chairman and Commissioners,
 
The Arizona Solar Energy Industries Association (AriSEIA) respectfully urges the Arizona Corporation Commission (Commission) to approve the Arizona Public Service Company (“APS”) Second Amended 2024 Demand Side Management (DSM) Implementation Plan as filed, along with the Utilities Division Staff Recommended Opinion and Order.
 
AriSEIA supports approval of the APS Second Amended 2024 DSM Implementation Plan[1] because the record demonstrates that the proposed measures comply with the Arizona Administrative Code requirements for cost-effective DSM programs and because the Utilities Division Staff Recommended Opinion and Order concludes that the updated portfolio meets applicable evaluation criteria.[2] AriSEIA’s interest is ensuring a stable, predictable regulatory landscape for distributed energy resources and demand-side programs. Approval of the plan, along with the Staff recommendation, provides needed clarity for market participants, customers, and project developers.
 
AriSEIA also strongly urges the Commission to preserve the Bring Your Own Device (BYOD) Virtual Power Plant Battery Pilot Program even if other changes to the DSM portfolio are considered. The BYOD program has been approved twice by vote of the Commission and resulted from a fully litigated rate case. It is a pay-for-performance-only program designed to compensate customers strictly for verified grid services. The Commission approved BYOD for a five-year term, and the program has not yet operated through even a single summer season. Premature modification or suspension would undermine the purpose of the pilot, create regulatory uncertainty, and diminish the value of distributed demand response resources that the Commission has repeatedly endorsed.
 
The BYOD pilot is also an essential contributor to APS’s projected portfolio-wide capacity savings. APS estimates that BYOD could enroll up to five thousand customers and contribute approximately 17 MW of dispatchable capacity during the pilot period.[3] These distributed, flexible resources play a significant role in meeting peak demand, reducing system costs, and increasing grid resilience for all APS customers.
 
For these reasons, AriSEIA supports approval of the Second Amended 2024 DSM Implementation Plan and the Utilities Division Staff Recommended Opinion and Order. If the Commission elects to modify the plan, AriSEIA respectfully asks that the Commission preserve the BYOD pilot in its entirety, including all funding allocated to the program in this plan, consistent with the Commission’s prior decisions and the purpose of the pilot itself.
 
Thank you for your consideration.
 
Respectfully,
 
/s/ Autumn T. Johnson
Executive Director
AriSEIA 
(520) 240-4757
[email protected]

[1] Application of Arizona Public Service Company for Approval of Its Second Amended 2024 Demand Side Management Implementation Plan, Docket No. E-01345A-23-0088 (filed June 20, 2025).

[2] Utilities Division Staff, Recommended Opinion and Order, Docket No. E-01345A-23-0088 (Nov. 19, 2025).

[3] Application of Arizona Public Service Company for Approval of Its Second Amended 2024 Demand Side Management Implementation Plan, Docket No. E-01345A-23-0088 (filed June 20, 2025) at page 3.

City of Mesa
20 E. Main Street
Mesa, AZ 85201
 
RE: Comments on Item 7 of the December 1 Agenda
 
Dear Mayor and Councilmembers,
 
On behalf of the Arizona Solar Energy Industries Association (AriSEIA), I urge you to reject the proposed 1,000 foot setback for battery energy storage systems (BESS) in Agenda Item 7. AriSEIA is Arizona’s solar, storage, and electrification trade association, and we previously submitted detailed BESS comments to the City in our October 15, 2025 letter.
 
A 1,000 foot setback is arbitrary, unsupported by data or national standards, and would function as a de facto moratorium on BESS in Mesa at the very moment when the region is facing record peak demand and rapidly rising electricity bills. Arizona’s three largest utilities have all set new peak demand records in recent summers, and Salt River Project expects continued significant load growth over the coming decade.[1] These conditions require more flexible, dispatchable resources, not fewer.
 
When this ordinance was before the Planning and Zoning Board, the 400 foot setback already under consideration was too large. Every member of the public who testified spoke against it and urged you to follow national standards instead. Yet, staff has proposed increasing the setback to 1,000 feet. That change moves Mesa even further away from evidence based practice.
 
National guidance and emerging practice in other jurisdictions point in a very different direction. The American Planning Association’s Zoning Practice review of BESS ordinances found that BESS specific setbacks in adopted codes are typically in the range of 50 to 150 feet from property lines.[2]
 
In addition, The National Fire Protection Association (NFPA) 855, the national consensus standard for installation of stationary energy storage, and related guidance used by fire professionals recommend a 100 foot separation between large outdoor BESS and nearby buildings or public ways to manage worst case thermal and blast scenarios.[3] Many jurisdictions address BESS separation primarily through adoption of NFPA 855 and the International Fire Code, combined with project specific review by the fire authority that can consider technology type, enclosure design, fire barriers, and egress.
 
Maricopa County provides a good example of this approach. County staff initially proposed a 500 foot separation between BESS and existing off site residences, but after hearing from fire experts and stakeholders, the Planning and Zoning Commission advanced an ordinance that dropped the 500 foot residential separation.[4] In other words, the County chose not to create a second, much larger layer of BESS specific zoning setbacks on top of the fire code.
 
By contrast, a 1,000 foot setback from BESS equipment to homes, churches, and similar uses in Mesa would:
 
• Push viable sites so far from load that projects become infeasible or uneconomic.
• Single out BESS for treatment that is far more restrictive than other critical energy infrastructure, such as substations.
• Effectively ban standalone BESS projects in most of the City while still allowing other, higher risk facilities at much closer distances.
 
Mesa does not need to reinvent the wheel. There are several defensible paths available to the Council that are protective of public safety and aligned with best practice:
 
1.      Follow the Maricopa County model and rely primarily on the fire code.
Mesa can remove the BESS specific separation requirement from the zoning text and allow the adopted fire code, which incorporates NFPA 855 requirements and related standards, to govern separation distances, fire protection features, and emergency response planning, with project specific review by Mesa Fire and Medical.
 
2.      If the Council decides to retain a numeric setback, it should align with national standards.
A maximum of 100 feet from BESS equipment to property lines is consistent with NFPA 855 guidance and with conditions used in Maricopa County approvals. This distance should always be measured from the BESS structure itself and not from the property line of the BESS parcel.
 
3.      If the Council wants an additional margin of comfort, it should not exceed 150 feet.
Buckeye has already adopted a 150 foot standard, based on the Phoenix Regional Standard Operating Procedures for BESS and NFPA guidance.[5] A 150 foot limit would still be conservative relative to many jurisdictions yet it would remain within the range documented by the American Planning Association.
 
Adopting a 1,000 foot setback would place Mesa well outside the mainstream of BESS regulation, chill investment in energy storage, and worsen the very reliability and affordability challenges your residents are already facing. A more measured, standards based approach is both safer and more practical.
 
For these reasons, AriSEIA respectfully asks the Council to reject the proposed 1,000 foot setback in Agenda Item 7, remove the BESS specific separation requirement from the zoning text or, at most, replace it with a setback no greater than 100 to 150 feet that is tied to NFPA 855 and Mesa’s adopted fire code.
 
Thank you for your consideration and for your continued work on policies that keep Mesa safe, reliable, and affordable while enabling clean energy investment.
 
Respectfully,
/s/ Autumn T. Johnson
Executive Director
AriSEIA 
(520) 240-4757
[email protected]

[1] Pinal County, Board of Supervisors meeting, Sept. 10, 2025, available here https://pinalcountyaz.new.swagit.com/videos/355087?ts=230.
Utility Dive. “Arizona utilities hit new peak demand during extreme heat.” July 2023.
Available at: https://www.utilitydive.com/news/arizona-utilities-peak-demand-heat-wave/686198/

[2] American Planning Association. Zoning Practice: Regulating Battery Energy Storage Systems. March 2024.
Available at: https://planning-org-uploaded-media.s3.amazonaws.com/publication/download_pdf/Zoning-Practice-2024-03.pdf

[3] National Fire Protection Association. NFPA 855: Standard for the Installation of Stationary Energy Storage Systems. 2023 edition.
UL. UL 9540A Test Method for Evaluating Thermal Runaway Fire Propagation in Battery Energy Storage Systems.

[4] Maricopa County Planning and Zoning Commission. Public Hearing on Text Amendment TA2024001 (Battery Energy Storage Systems). November 6, 2024.

[5] City of Buckeye. Zoning Code, Article 3: Use Regulations. Battery Energy Storage Systems standards adopted October 21, 2025.

Arizona Public Service
400 N 5th Street
Phoenix, AZ 85004
 
RE: AriSEIA Comments on the APS Interconnection Manual Draft Rev. 9.1 
 
Dear APS Interconnection Team,
 
The Arizona Solar Energy Industries Association (AriSEIA) appreciates the opportunity to provide comments on Arizona Public Service Company’s Interconnection Requirements Manual, Revision 9.1. These comments are intended to support clarity, consistency, and compliance with the Arizona Corporation Commission’s interconnection rules, particularly as they relate to Maximum Capacity, screening criteria, and the treatment of Active Power Limiting systems.
 
AriSEIA’s overarching concerns fall into several categories. First, multiple sections of the Manual reference Nameplate Capacity where Maximum Capacity is required under Arizona Administrative Code R14-2-2615. Consistent and accurate use of the defined regulatory terms is essential to ensure uniform application of the screening process and to prevent inadvertent misclassification of generating facilities.
 
Second, several provisions governing Active Power Limiting systems do not fully align with Arizona Corporation Commission requirements or with best practices used in other jurisdictions. These include scope limitations, terminology inconsistencies, and restrictions that would unnecessarily limit non-parallel operating modes that are widely expected to become more common as solar and storage penetration increases.
 
Third, certain protection and monitoring requirements would benefit from additional specificity to improve predictability for both developers and reviewers. In particular, clarification of Minimum Power Protection settings and the definition of the Relative Generating Facility Rating will help ensure consistent implementation across projects.
 
A detailed list of recommended revisions is attached. These recommendations include requested edits to sections 8.1, 8.3, 10.4, 12.2, and related protection and control provisions. Each recommended change is tied either to Arizona Corporation Commission rule requirements or to accepted technical standards used in other jurisdictions.
 
AriSEIA appreciates APS’s attention to these issues and remains committed to constructive engagement to support an interconnection process that is efficient, transparent, and compliant with state requirements. Please do not hesitate to contact us with any questions.
 
Sincerely,
/s/ Autumn T. Johnson
Executive Director
AriSEIA 
(520) 240-4757
[email protected]

AriSEIA has previously filed multiple times in both dockets in opposition to the rules repeal. However, the Commission does not count any comments filed before August 19, 2025 as part of the REST record or comments filed before September 26, 2025 as part of the EE record, so AriSEIA filed ours (and everyone else's) again.