Apache County Board of Supervisors
P.O. Box 428
St. Johns, AZ 85936
 
Re: Proposed Article 8 Renewable Energy Ordinance (Draft 9.5) – Correcting the Record on Stakeholder Input
 
Dear Supervisors, Commissioners, and Staff,
 
The Arizona Solar Energy Industries Association (AriSEIA) writes ahead of the October 13 special work session to correct the record from the September 22 work session. At that session, a Commissioner asked why people from both sides were not helping with the ordinance. The response was that people supportive of renewable energy had been invited but were not present. The Chair added that developers had a lot of input in the early stages and should not be writing the ordinance. This leaves the impression that the County has heard only from opponents of renewable energy. That impression is false.
 
AriSEIA’s Comments Are On The Record And Remain Applicable
 
AriSEIA has taken part in this process since May 2025. Over the last year and a half, we submitted formal comment letters on December 3, 2025; January 12, 2026; March 4, 2026; May 23, 2026; and July 27, 2026. These letters included specific replacement language and an independent economic impact analysis by Elliott D. Pollack & Company. All of them are available at https://www.ariseia.org/news/category/apache-county.
 
AriSEIA is a trade association, not a project developer. Our comments are meant to produce an ordinance that is workable for any project, and they remain applicable to Draft 9.5. We did not submit new comments by the September 15 deadline because our earlier comments were not addressed. Draft 9.5 keeps or reinstates many provisions we have repeatedly flagged:

• A one-megawatt applicability threshold that sweeps in small commercial and agricultural systems;
• A requirement for interconnection and power purchase agreements before building permits;
• A communications interference process that can trigger investigation and curtailment from a single complaint;
• Definitions that pull gen-tie lines and transmission infrastructure into the ordinance; and
• Requirements that outside agency and fire district approvals be in hand before a CUP can be heard.

 
The Ordinance Is Now Being Drafted From A Single Viewpoint
 
The Commission previously voted to advance a moratorium on renewable energy development, which the Board did not adopt. The Commission is now rewriting an ordinance that staff and stakeholders spent more than a year developing. At the August 25 and September 22 work sessions, the same small group of local residents who oppose these projects presented the revisions. They are also preparing rewritten sections and delivering them to Commissioners in advance of each meeting alongside staff. No comparable role has been offered to anyone with a different view. The results show this. On September 22 alone, the Commission added preferred criteria and intent language that:

• Steer projects to the “most remote and sparsely populated areas” of the County;
• Prefer sites at least 10 miles from visual resources;
• Prefer sites downwind of populated areas;
• Prohibit industrial wind construction in the Springerville Volcanic Field; and
• State that the ordinance is meant to keep utility-scale renewable energy from becoming a routine use in Supervisor District III.

 
The Community Development Director asked during that session whether the point of these changes was to make the ordinance as restrictive as possible. That is a fair question, and the Board should be asking it too.
 
Many People Are Not Commenting Because They Have Been Ignored Or Do Not Feel Safe
 
Silence from supporters is not agreement. Many residents, landowners, and businesses have already commented and seen their input set aside. Others do not feel safe taking part. The Commission itself discussed this on August 25. One Commissioner’s colt and two calves were killed, and he received an online statement widely understood as a death threat. Another Commissioner resigned after he believed his water dispensing system, essential to his business, had been intentionally contaminated. The Commission decided at that meeting to redact property owner names from public application documents because of retaliation in the community. Multiple Commissioners have now stepped down. Conduct toward County officials became serious enough that the Stop Lava Run group publicly asked people to stop threatening them.
 
When the County’s own Commissioners and participating landowners need protection from retaliation, it is not reasonable to read the absence of public support as a lack of support.
 
Meetings Are Not Accessible To Much Of The County
 
Apache County is one of the largest counties in the country. Many residents live hours from St. Johns, and work sessions do not offer remote participation. Even apart from the safety concerns above, broad public input is not possible under these conditions. AriSEIA recommended remote participation in July and renews that request now.
 
A De Facto Moratorium Exposes The County To Legal Risk
 
Landowners in Apache County have property rights, including the right to lease their land for lawful uses. A county moratorium must meet the requirements of A.R.S. § 11-833, including specific written findings and a factual basis. A land use regulation that reduces the value of private property may also give rise to claims for just compensation under A.R.S. § 12-1134. Draft 9.5 itself states that the record must show the factual basis for each standard.
 
Staff has already warned about this. On September 22, the Community Development Director cautioned that making preferred areas mandatory would attract significantly more attention. An ordinance that uses setbacks, siting preferences, thresholds, and procedural barriers to achieve what a moratorium could not achieve directly invites the same challenges.
 
We are also concerned by the Chair’s statement on September 22. He said that although the new ordinance will not apply to pending applications, the County can add CUP conditions that match the draft. Applying unadopted standards to applications filed under the existing ordinance would add to that legal exposure.
 
AriSEIA’s Requests
 
AriSEIA respectfully asks the Board, the Commission, and staff to:

1. Correct the record to reflect that AriSEIA and other stakeholders have submitted substantive comments throughout this process;
2. Review and respond to AriSEIA’s prior comment letters before further action on Draft 9.5;
3. Give stakeholders with differing views the same drafting role now given to opponents;
4. Provide remote participation for all remaining work sessions and hearings;
5. Evaluate pending CUP applications under the ordinance in effect when they were filed; and
6. Return to the balanced framework developed with staff and stakeholders rather than adopting an ordinance that operates as a de facto prohibition.

 
AriSEIA remains a willing partner and would welcome the opportunity to meet with Supervisors, Commissioners, or staff.
 
Respectfully,
/s/ Autumn T. Johnson
Executive Director
AriSEIA 
(520) 240-4757
[email protected]

City of Tucson Planning Commission
c/o Planning and Development Services
P.O. Box 27210
Tucson, AZ 85726-7210
Via email: [email protected]
 
RE: Agenda Item 5, CODE Tucson '26 Code Amendment (C8-25-03), Attachment E – Proposed Battery Energy Storage System Amendment
 
Dear Chair and Commissioners,
 
The Arizona Solar Energy Industries Association (AriSEIA) is the statewide trade association for the solar, storage, and electrification industry. We have engaged extensively on battery energy storage system (BESS) ordinances across Arizona, including in Maricopa County and the Cities of Mesa, Buckeye, Goodyear, and Surprise. We appreciate staff's work on the CODE Tucson '26 package and support the City's goal of creating a clear pathway for this critical infrastructure.
 
AriSEIA respectfully requests that the Commission continue the BESS amendment (Attachment E and the "Define battery storage use" item), or sever it from the CODE Tucson '26 package so the remaining amendments may proceed, to allow for a stakeholder process on the new proposal.
 
Request for Continuance
According to the staff memorandum, the BESS proposal reviewed at the August 26 and September 16 study sessions would have added BESS as part of the existing Distribution System use. After the September 16 study session, that approach was replaced with a standalone, two-tier use and eleven new use-specific standards.
 
This new version first appeared in the October 1 packet for the October 7 hearing. It has not been presented at a study session. It was not part of the surveys or community meetings described in the memorandum. To our knowledge, it has not been shared with the storage industry, Tucson Electric Power, or the commercial and institutional customers it would directly affect.
 
AriSEIA did not learn of the proposal until Friday, October 2. Three business days is not enough time for affected businesses, schools, hospitals, and developers to review it, let alone engage meaningfully. A short continuance would allow staff to hold at least one stakeholder meeting with industry, Tucson Electric Power, and the Tucson Fire Department, and return with a proposal tested against real projects. Severing the BESS item would let the rest of the package move forward on schedule.
 
AriSEIA's preliminary comments on the substance of the proposal follow.

1. Size Thresholds and Commercial and Industrial Systems
The proposed thresholds are far too small. A "Bulk Power" facility begins at 1 MW or 4 MWh, a system that may fit in one or two shipping-container-sized enclosures. Treating a system of that size like a large utility-scale facility will sweep in modest projects that pose no unique land use concerns.
 
The "Distributed" tier is even broader. It would regulate commercial, industrial, institutional, and microgrid systems starting at only 80 kWh, capturing:
·         batteries paired with rooftop solar at small businesses,
·         backup power at schools, churches, and hospitals,
·         battery-buffered EV charging,
·         storage at multifamily properties.
 
These customer-sited systems serve on-site load. They are already governed by the City's adopted building, electrical, and fire codes, and other Arizona jurisdictions have excluded them. Mesa expressly excludes accessory systems serving the enterprise functions of the on-site owner or tenant.[1] Maricopa County distinguishes utility-scale systems from customer-sited systems.[2]
The tier structure also leaves gaps. Behind-the-meter systems at or above 1 MW, and front-of-the-meter systems below 1 MW, fall into neither tier. Under the use tables, they would have no permitted path.
 
AriSEIA recommends eliminating the Distributed tier. All commercial, industrial, and institutional behind-the-meter systems should be exempt, and at a minimum any such system under 10 MW. The ordinance should apply only to front-of-the-meter, utility-scale facilities of 10 MW or greater.
At an absolute minimum, the City should follow the City of Surprise, which adopted a 5 MW threshold for accessory battery systems in its BESS ordinance on September 1, 2026.[3] Surprise has more direct experience with BESS safety than any jurisdiction in Arizona, and it concluded that systems of this size do not warrant the same treatment as utility-scale facilities. Tucson's proposed thresholds of 80 kWh and 1 MW are far below that benchmark.
 
2. Limiting the Ordinance to Lithium-Ion Technology
The proposed definition covers "chemical, electrochemical, or mechanical" storage. The standards that follow, however, are framed around lithium-ion thermal runaway and off-gassing. Technologies such as flow batteries, iron-air, sodium-based chemistries, and mechanical storage have different characteristics and risk profiles. There is no evidentiary basis for assuming that the separation distances, barrier walls, and hazard standards in this proposal are appropriate for them.
​
National Fire Protection Association (NFPA) 855 already contains technology-specific provisions for these systems. Applying lithium-ion-based zoning standards to every storage technology risks both over-regulating emerging technologies and locking in requirements the City may later need to undo. AriSEIA recommends the following definition:
 
"Battery Energy Storage System (BESS), Utility-Scale: A stationary lithium-ion battery energy storage facility with a rated power capacity of 10 MW or greater, located in front of the customer meter and designed for energy market participation or grid services. Systems installed behind the customer meter or primarily serving on-site load, including residential, commercial, industrial, and institutional systems, are exempt from this use and its associated standards. Energy storage technologies other than lithium-ion shall be classified as a Distribution System use and reviewed in accordance with the City's adopted building, electrical, and fire codes."
 
3. Zoning Districts and Solar-Plus-Storage
Bulk BESS is limited to industrial zones by right and to C-2, C-3, and P-I by special exception. Utility-scale storage is often best located in rural and large-lot areas near transmission and away from population centers. The special exception process already lets the City evaluate compatibility case by case.
 
AriSEIA recommends making utility-scale BESS eligible for special exception review in rural and large-lot districts. AriSEIA also supports the City’s previous consideration of classifying BESS as a utility distribution use. BESS should be allowed in the same zoning districts where Distribution Systems are currently permitted, including C-1, C-2, C-3, OCR-1, and OCR-2, subject to sensible and industry-vetted use-specific standards. This approach recognizes the role that energy storage plays in supporting electric system reliability while providing the City with clear review standards.
 
The ordinance should also state that BESS is a permitted accessory use to an approved solar facility, without a separate approval.
 
4. Separation Requirements
AriSEIA appreciates that the proposed 150-foot residential separation is consistent with Buckeye's adopted standard and the range identified by the American Planning Association.[4] Maricopa County requires 100 feet from lot lines.[5]
 
However, the separation should be measured to existing residential structures, not to a residential zoning district boundary line. A zoning boundary line may border vacant land, rights-of-way, or portions of a parcel hundreds of feet from any home. Measuring to the boundary line effectively expands the separation well beyond 150 feet. It does so without any corresponding safety benefit, because the stated purpose of the separation is to protect people. AriSEIA recommends:
 
"An outdoor utility-scale BESS shall be located no closer than one hundred fifty feet (150') from an existing residential dwelling unit, measured in a straight line from the outermost battery cabinet to the nearest exterior wall of the dwelling."
 
The additional 300-foot separation from schools, daycares, hospitals, senior living, and "high-occupancy assembly use" should be removed. These are the very facilities most likely to install batteries themselves for backup power and resilience, often inside or immediately adjacent to the occupied building. A rule that treats a battery 299 feet from a hospital as unacceptable, while the hospital may operate its own battery on site, is internally inconsistent and has no technical basis. "High-occupancy assembly use" is also undefined, which invites inconsistent application. The 150-foot standard measured to existing structures is sufficient.
 
The relief mechanism also needs revision. It allows only a 25% reduction, and only on a showing that a barrier wall achieves "identical safety metrics." Standard 7 already requires that wall, so the same mitigation is counted against the applicant twice. It should be replaced with the general waiver discussed below.
 
5. No Retroactive Application
Several provisions, including the abandonment standard, apply to "any BESS facility" without limitation. BESS facilities should be required to comply with the zoning requirements in effect when they are installed. They cannot practically be required to meet new standards retroactively. An existing facility cannot be relocated to satisfy a new separation distance. It cannot be rebuilt behind a wall designed after it was constructed. It cannot re-engineer equipment to meet a noise limit that did not exist when it was permitted. AriSEIA recommends adding:
 
"The requirements of this section apply only to BESS facilities for which a complete application is submitted after the effective date. Facilities installed, permitted, or with a complete application on file before the effective date shall be governed by the regulations in effect at that time. Routine maintenance, repair, and augmentation within the approved footprint shall not subject an existing facility to this section."
 
6. Hazard Evaluation and Reliance on National Standards
Standard 5 requires an applicant to demonstrate, to the satisfaction of the City, that "any potential failure scenario" can be contained on-site. That standard is subjective and open-ended, and no applicant can meet it with certainty. National standards already address this subject comprehensively. NFPA 855 requires:
·         a Hazard Mitigation Analysis,
·         an emergency response plan,
·         commissioning,
·         large-scale fire testing under UL 9540A for systems listed to UL 9540.[6]
 
AriSEIA recommends that Standards 3 through 5 expressly require compliance with the currently adopted edition of NFPA 855, UL 9540, and UL 9540A. Those submittals should be due at building permit, when equipment and design are known, rather than at zoning approval.
 
7. Noise
The proposed limits of 55 dBA at a commercial property line and 45 dBA at a residential property line are far too low. A 55 dBA limit at a commercial property line is roughly the level of normal conversation. It is quieter than the rooftop HVAC equipment found on virtually every commercial building in Tucson. The residential limit is quieter still.
 
These limits are not applied to other utility or mechanical uses. They would single out BESS in the same package in which the City is updating its general noise regulations. AriSEIA recommends that BESS be subject to the same noise rules as other land uses. In the alternative, the ordinance should use an objective limit of 65 dBA at the project boundary, demonstrated by a qualified acoustical engineer.
 
8. Indoor Requirement
Standard 11 requires BESS to be located entirely within an enclosed primary structure or parking garage, with any outdoor installation requiring a special exception. Requiring BESS to be placed within enclosed structures or parking garages runs counter to the direction of modern industry practice. Based on industry lessons learned from operating experience and battery incidents, the industry has moved towards outdoor BESS installations in non-occupiable enclosures, rather than locating batteries inside occupiable or enclosed buildings. Outdoor installations are the safer and more appropriate configuration for BESS.
.
Indoor installations generally trigger more demanding fire code requirements than outdoor ones. They are also harder for firefighters to access and ventilate. Outdoor siting in purpose-built enclosures is often the configuration fire officials prefer. Parking garages in particular are enclosed, occupied spaces that are poorly suited to battery placement.
 
The provision would also bar a standard outdoor cabinet behind a downtown building without a special exception, while pushing the same equipment into a less desirable indoor location. AriSEIA recommends removing Standard 11 and allowing outdoor installations in these zones subject to the same standards that apply elsewhere.
 
9. Walls and Landscaping
AriSEIA does not object to 8-to-10-foot screen walls where screening is appropriate. However, Standard 7 goes further. It requires every outdoor equipment yard to be enclosed by a reinforced masonry wall "designed to serve as a thermal and blast barrier." No national standard defines or calls for such a wall. NFPA 855 addresses explosion control at the enclosure level, and a solid perimeter wall can complicate ventilation and fire department access.
 
Standard 8 adds a mandatory 10-foot landscape border outside the wall, which increases land requirements and water use. AriSEIA recommends treating walls as screening rather than blast barriers. Staff should also have authority to approve alternative perimeter treatments where site conditions warrant, as Buckeye and Maricopa County allow.
 
10. Decommissioning and Abandonment
Standard 9 requires restoration to a "greenfield state." That is not a meaningful standard for sites that were parking lots or previously-developed  land before BESS construction. It also requires a recorded plan signed by the system operator before building permit, when the operator may not yet be known. Restoration should be to pre-construction condition, and the plan should be due before certificate of occupancy.
 
Standard 10 deems a facility abandoned after 12 months without operating or delivering power to the grid. The standard should:
·         apply only to utility-scale facilities installed after the effective date,
·         exclude periods of repair, augmentation, interconnection delay, and force majeure,
·         clarify what "deploy" means.
 
11. Waiver and Administrative Modifications
The ordinance should include a general waiver provision and administrative approval of routine modifications. AriSEIA recommends:
 
"The Zoning Examiner may grant a waiver from specific requirements of this section upon a finding that the proposed alternative provides equivalent or greater protection for public safety and compatibility with surrounding land uses."
 
"Administrative approval may be granted for modifications that do not increase the approved project footprint, reduce required separations, or materially alter approved access, emergency response, or fire protection features."
 
Conclusion
Battery storage is increasingly essential to grid reliability and affordability in Southern Arizona. A well-designed ordinance can protect residents while giving applicants a clear, workable path.
The current proposal does not do that. Its size thresholds are too small, and it reaches customer-sited systems that should be exempt. It applies lithium-ion-based standards to technologies they were not designed for, and measures separation to zoning lines rather than homes. It penalizes proximity to facilities that use batteries themselves, and it imposes noise and indoor-siting requirements that do not reflect real-world conditions or fire safety practices.
 
These issues can be resolved, but not in three business days. AriSEIA respectfully asks the Commission to continue or sever the BESS amendment, and we welcome the opportunity to work with staff on a revised proposal.
 
Respectfully,
/s/ Autumn T. Johnson
Executive Director
AriSEIA 
(520) 240-4757
[email protected]
 
[1] Mesa City Code § 11-31-37; Mesa Resolution 12441 (Dec. 1, 2025), https://www.mesaaz.gov/files/assets/public/v/1/business-development/devsvcs/codesords/bess-adoption-by-ref-doc.pdf.
[2] Maricopa County Zoning Ordinance art. 603.10, https://esd.maricopa.gov/DocumentCenter/View/4785/P-18---Zoning-Ordinance-PDF?bidId=.
[3] City of Surprise, Ordinance No. [____] (Sept. 1, 2026), Case FS23-1041, Battery Energy Storage System Overlay.
[4] American Planning Association, Zoning Practice: Battery Energy Storage Systems 10 (Mar. 2024), https://planning-org-uploaded-media.s3.amazonaws.com/publication/download_pdf/Zoning-Practice-2024-03.pdf; City of Buckeye Development Code § 3.2, https://library.municode.com/az/buckeye/codes/code_of_ordinances?nodeId=CD_ORD_CH7DECO.
[5] Maricopa County Zoning Ordinance art. 603.10, supra note 2.
[6] NFPA 855, Standard for the Installation of Stationary Energy Storage Systems (2023 ed.); UL 9540, Energy Storage Systems and Equipment; UL 9540A, Test Method for Evaluating Thermal Runaway Fire Propagation in Battery Energy Storage Systems.

Arizona Corporation Commission
1200 West Washington Street
Phoenix, Arizona 85007
 
Re: CG Apache County Solar LLC and CG Apache County Wind LLC, Docket Nos. L-21365A-25-0198-00250 and L-21364A-25-0198-00250
 
Dear Chairman and Commissioners,
 
The Arizona Solar Energy Industries Association (AriSEIA) is a nonprofit trade association. It represents Arizona's solar, storage, and electrification industry. AriSEIA regularly takes part in proceedings before the Arizona Corporation Commission and has been directly and continuously involved in Apache County's renewable energy ordinance process.
 
AriSEIA submits this letter in response to public comments asking the Commission to hold off on voting on the Certificate of Environmental Compatibility (CEC) for the Lava Run Interconnection Project until Apache County revises its existing renewable energy ordinance. AriSEIA respectfully urges the Commission to reject that request and proceed to a vote. There are three reasons. The request has nothing to do with the project before the Commission. The Line Siting Committee has already considered it. And it would tie this proceeding to a county process with no end date in sight.
 
1. Apache County already has a renewable energy ordinance.
These comments assume that Apache County lacks the rules it needs to govern renewable development. That is not the case. The County has a renewable energy ordinance in effect today, and applicants can submit projects under it. The ongoing revision updates that ordinance; it does not fill a regulatory gap. The pending revision does not stop the County from exercising its land use authority over generation facilities now. It also has no bearing on the Commission's ability to act on this CEC.
 
2. The ordinance does not apply to transmission lines, and the revised ordinance will not either.
The Lava Run Interconnection Project is a 345-kV generation tie transmission line with associated interconnection facilities. The Commission's jurisdiction over that line comes from A.R.S. §§ 40-360 et seq. Apache County's renewable energy ordinance, both the current version and the one being revised, governs renewable generation facilities. It does not regulate transmission lines. Throughout the revision process, AriSEIA has consistently urged the County to keep transmission and interconnection facilities outside the ordinance. Those facilities are already covered by separate state and federal frameworks, including this one. Delaying a decision on a transmission line until the County finishes an ordinance that will not govern that line serves no purpose.
 
3. The County's revision process has no end date.
AriSEIA has taken part in the revision of Apache County's ordinance since May 2025. Since then, AriSEIA has submitted multiple formal comment letters, and the draft has gone through eight versions. In July 2026, instead of adopting the ordinance, the Board of Supervisors considered sending it to another subcommittee for more review. It is unclear when, or whether, the County will finish this ordinance. Making the Commission's vote depend on that outcome would suspend this proceeding indefinitely.
 
4. The ordinance process has been marked by a moratorium attempt, resignations, and harassment.
The body working on the ordinance has already tried to advance a moratorium on renewable energy development. The Board of Supervisors never took up that proposal. Three Planning and Zoning commissioners have since stepped down. People taking part in the process have been harassed and threatened. AriSEIA raised these concerns directly with the County in July 2026, noting that no stakeholder should fear retaliation for participating in a local government process. Arguing that a state certificate should wait on a process in this condition is not a good faith argument. A delay would reward the conduct that has stalled the County's work.
 
5. The Line Siting Committee has already considered this issue.
The Arizona Power Plant and Transmission Line Siting Committee held two full hearings on this matter. The status of Apache County's ordinance was before the Committee, and the Committee made its decision with that information in hand. The people raising this argument now are asking the Commission to reopen a question the Committee has already heard and resolved. That, too, is not a good faith argument.
 
Conclusion
The Lava Run Interconnection Project is a transmission line properly before the Commission under A.R.S. §§ 40-360 et seq. Apache County's renewable energy ordinance, existing or revised, does not govern it. The Line Siting Committee has already weighed the arguments for delay after two full hearings. AriSEIA respectfully urges the Commission to decline the request to postpone and to proceed to a vote on the Committee's Decision on Remand.
 
For the Commission's reference, AriSEIA's prior comment letters to Apache County on the renewable energy ordinance are available at: https://www.ariseia.org/news/category/apache-county.
 
Respectfully,
/s/ Autumn T. Johnson
Executive Director
AriSEIA 
(520) 240-4757
[email protected]
​

City of Willcox
101 S. Railroad Avenue, Suite B
Willcox, Arizona 85643
 
Re: Community Benefit Agreements for Utility-Scale Solar and Energy Storage
 
Thank you for contacting the Arizona Solar Energy Industries Association (AriSEIA) for insight into how community benefit agreements are being structured for utility-scale solar and energy storage projects. AriSEIA appreciates the City's thoughtful approach, and in particular its goal of agreements that are competitive and reasonable for the industry while providing an equitable, long-term benefit to the community.
 
AriSEIA has some concerns about the utilization of community benefit agreements. We believe renewables projects should be treated on par with other electric generation projects and are concerned about only renewables projects being priced out of competitive solicitation processes. Additionally, every project and every community is different, so any agreement should be tailored to the specific project rather than set by a uniform formula. Where a community does pursue an agreement, AriSEIA hopes the information below helps it reach terms that serve the community without putting solar and storage at a competitive disadvantage.
 
Arizona Needs New Supply, And Every Resource Competes On Price
Arizona's electricity demand is growing rapidly. Arizona Public Service (APS) has said the state's energy needs are growing faster than at any time in its history, driven in part by unprecedented requests from extra-large users such as data centers.¹ Salt River Project (SRP) has likewise cited continued projected growth in its service territory as the reason it needs additional generation to keep service reliable and affordable.²
 
Meeting that demand requires new supply, and utilities choose among resources through competitive, all-source procurements. In SRP's 2026 All-Source Request for Proposals (RFP), for example, bids from solar, storage, and other developers are compared against SRP's own self-build options for natural gas, solar, and storage.³ Every resource competes on price for the same contracts.
 
For that reason, community benefit requirements should apply equally to every form of generation, not to renewable energy alone. SRP's approach reflects this principle, because its one-time community contribution is a minimum requirement for every proposal regardless of the resource technology proposed.⁴ Some local requirements in Arizona, by contrast, apply only to renewable energy facilities.⁵ When a requirement falls only on solar and storage, it raises the cost of those projects alone and can price them out of the competitive solicitations that determine which resources get built. The community then loses the project, along with the jobs, tax revenue, and water savings described below. Electric bills for all customers also rise when new power costs more to build
 
The Value Solar Projects Already Provide
AriSEIA commissioned Elliott D. Pollack & Company to analyze a representative utility-scale project in Arizona: a 400-megawatt (MW) solar facility with 400 MW of four-hour battery storage on about 2,400 acres, with a taxable original cost of approximately $874.8 million. The full study is attached. It found that the project would support approximately 690 construction and related jobs and $63.2 million in wages, and would generate $170.1 million in total economic impact from construction, including $101.4 million in direct construction spending. Once operating, the project would generate an estimated $14.2 million in economic activity each year and more than $736.7 million over its life.⁶
 
The tax benefits are equally significant. Over a 40-year life, the project would generate approximately $36.4 million in tax revenue for local taxing jurisdictions, averaging about $905,770 per year. The local school district would receive the largest share, an estimated $18.8 million over the project's life or about $468,800 per year. These figures do not include the increase in real property taxes when land is reclassified from vacant to commercial or industrial use, which has raised assessed value per acre by an average of roughly 50 percent. They also exclude use taxes on non-exempt equipment.⁷
 
The study models a project in Maricopa County, so figures for projects elsewhere would reflect local tax rates and the specifics of each project, but the scale of benefit is representative. Because equipment value depreciates, property tax revenue is highest in a project's early years. That is one reason AriSEIA favors pairing tax revenue with a community fund designed to last the life of the project, as described below.
 
Water
Water deserves particular attention in the Willcox Basin. In December 2024, the Director of the Arizona Department of Water Resources designated the Willcox Groundwater Basin as Arizona's seventh Active Management Area, finding that active management was necessary to preserve the basin's existing groundwater supply for future needs and that land subsidence and earth fissuring were endangering property and groundwater storage capacity.⁸ The Department is now developing the first management plan for the new Active Management Area.⁹
 
A 2024 analysis prepared for AriSEIA by WestWater Research, using Arizona Department of Water Resources data, is also attached. It compared solar with other uses land might be put to and found that solar uses far less water than any of them. Solar facilities use about 0.03 acre-feet of water per acre per year, compared with 2.3 acre-feet for subdivisions, 3.6 for manufacturing, 4.1 for irrigated agriculture, and 6.3 for data centers. Per megawatt, solar uses about 0.16 acre-feet per year, compared with 4.3 acre-feet for natural gas generation and 18.7 acre-feet for nuclear.¹⁰ For a basin working to preserve its groundwater, few forms of development place less demand on the aquifer.

Per-Megawatt Benchmarks
The City asked whether developers commonly use a per-megawatt benchmark. Such benchmarks are a common reference point, and there are two Arizona examples the City may come across. The first is SRP's 2026 All-Source RFP, which is publicly available on SRP's website. Section XII.H of that RFP requires a non-recurring, one-time contribution of $1,500 per megawatt of nameplate capacity, dedicated to supporting the surrounding community, and the requirement applies to every proposal regardless of technology.¹¹
 
The second is a proposed development agreement between Navajo County and the developer of the Chimney Canyon solar and storage project. For that 975-megawatt project, the agreement calls for a one-time payment of roughly $6.8 million, or about $7,000 per megawatt, after a credit for the County's estimated share of project property taxes.¹²
 
AriSEIA believes the Navajo County payment is much too high and that the SRP framing is the more appropriate benchmark, for four reasons. First, SRP applies its requirement equally to every technology competing in its solicitation, while the Navajo County requirement applies only to renewable energy. Second, at about $7,000 per megawatt, the Navajo County payment is more than four times the SRP benchmark and adds substantially to the cost of solar and storage projects that must compete on price against other resources. Third, the Navajo County agreement requires payment before a project operates, with $250,000 due when the building permit application is submitted and the balance due within 270 days after the building permit is issued.¹³ Fourth, a payment at that level would make Arizona communities less competitive for the projects they hope to attract.
 
The Navajo County agreement does include useful structural features, which AriSEIA recommends below: a one-time payment rather than annual payments, no escalator, a credit for property taxes, and firm commitments from the County in return. AriSEIA views contributions consistent with the SRP benchmark as reasonable and competitive for Arizona. Where a project already provides SRP's community contribution, those funds should be directed to the host community and credited toward any local agreement rather than duplicated.
 
Payment Only After Commercial Operation
AriSEIA's most important recommendation concerns timing. Any community contribution should be due only after a project begins commercial operation, and never at approval, at permitting, or at the start of construction. Many projects that receive local approval never reach construction because of interconnection delays, financing, or the outcome of competitive utility solicitations. A payment required before a project is built is a payment for a project that may never exist. Developers must recover that cost from the projects that do get built, which raises their prices in the same competitive procurements described above.
 
Tying payment to commercial operation protects both parties. The community receives its contribution from a project that is actually producing jobs, tax revenue, and power, and the developer is not asked to put capital at risk before the project is certain. The same principle should apply to every element of a community contribution. The one-time payment, the initial funding of any community fund, and the first scholarship awards should all begin once the project is operating.

Annual Versus One-Time Payments
AriSEIA recommends a one-time contribution, made at commercial operation, rather than annual payments. A one-time contribution gives the community certainty about what it will receive and gives the developer certainty about its costs, without creating an open-ended obligation over decades.
 
To meet the goal of benefits that extend over a project's useful life, a one-time contribution can be combined with an endowed community fund and a local scholarship program, both beginning at commercial operation. A fund held by a community foundation, for example, can provide grants to local organizations every year for the life of the project and beyond, while scholarships continue over the project's operating life. The total value of these contributions should be considered together and kept consistent with the SRP benchmark. Where the City receives property tax revenue from a project, that revenue should also be credited against the contribution, as in the Navajo County agreement,¹⁴ since it serves the same purpose.
 
Escalation provisions
AriSEIA does not recommend escalators. Neither SRP's benchmark nor the Navajo County agreement includes one.¹⁵ A one-time contribution and an endowed fund do not require them, and a project's property taxes are set under state law rather than by agreement.
 
Agreement Duration
The fund and scholarship program can begin at commercial operation and run for the full operating life of a project, typically 30 to 40 years, with a clear end date tied to decommissioning. This addresses the City's concern that benefits not end well before the project does. Construction-related obligations, such as road repair, would end once they are satisfied.
 
Solar Versus Battery Storage Capacity
SRP's benchmark counts a paired project once, rather than adding solar and storage capacity together. Its example is a 200 MW solar plus 200 MW storage project that contributes $300,000, which is $1,500 per megawatt applied to 200 MW, not 400 MW. The Navajo County agreement likewise bases its payment on generation capacity at the point of interconnection, and AriSEIA recommends the same approach.¹⁶
 
Other Community Investments
The most common additional commitment is repair of any damage to City roads caused by project construction, documented through pre- and post-construction road surveys. AriSEIA considers this appropriate. AriSEIA also suggests that a developer be permitted to satisfy part of its contribution through direct support of local 501(c)(3) organizations, so that the benefits reach the community directly.
 
Mutual Commitments
An agreement of this kind works best when it provides certainty to both parties, as the Navajo County agreement does.¹⁷ This approach is consistent with national research on renewable energy siting. A 2026 white paper, A Win-Win Solution for Clean Energy Siting, was prepared by the Siting Solutions Project with Dr. David E. Adelman of the University of Texas School of Law. It recommends development agreements and payments in lieu of taxes as tools that deliver visible benefits to communities while giving developers the certainty they need to build.¹⁸
 
The authors point to Riverside County, California, which adopted development agreements for solar projects in 2015 and now ranks second in the state for installed solar capacity.¹⁹ Following that model, in exchange for the community contribution, the agreement should do five things:
 
·         confirm that no contribution of any kind is due before the project begins commercial operation;
·         assure the developer that the project may proceed under the rules in effect when the agreement is signed;
·         set reasonable deadlines for City review of complete permit applications;
·         commit that no additional fees or exactions will be imposed; and
·         recognize that the agreed contribution fully addresses the project's community impacts.
 
AriSEIA would welcome the opportunity to meet with the City to discuss any of this further. Thank you again for reaching out, and for approaching this question in a way that considers both the needs of the community and the realities of the industry. This is an evolving area of practice and we will reach back out if we gather additional information that may be helpful to the City.
 
Respectfully,
/s/ Autumn T. Johnson
Executive Director
AriSEIA 
(520) 240-4757
[email protected]
 
Attachments:

1. Elliott D. Pollack & Company, Gila Bend Solar (Example Project) Economic Impact and Tax Revenue Analysis (June 2026).
2. WestWater Research, Arizona Water Demand Analysis by Land Use Category (October 9, 2024).

 
¹ Ariz. Pub. Serv., APS Uses "Growth Pays for Growth" Model to Develop New Natural Gas Plant, APS Newsroom (2025), https://www.aps.com/en/About/Our-Company/Newsroom/Articles/APS_Uses_Growth_Pays_For_Growth_Model_to_Develop_New_Natural_Gas_Plant.
² Salt River Project, 2026 All-Source Request for Proposals § I (Feb. 23, 2026), https://azure-na-assets.contentstack.com/v3/assets/bltefc1fc708dcc94e7/blt7c2744713c80d9b9/2026-All-Source-RFP.pdf.
³ Id.
⁴ Id. §§ XII, XII.H.
⁵ Development Agreement Between Navajo County and Chimney Canyon Energy Ctr. 1 LLC recital D (proposed 2026) (on file with the Ariz. Solar Energy Indus. Ass'n) [hereinafter Navajo County Development Agreement] (citing Navajo County, Ariz., Zoning Ordinance § 1201), https://www.navajocountyaz.gov/DocumentCenter/View/10209/Chimney-Canyon-Development-Agreement.
⁶ Elliott D. Pollack & Co., Gila Bend Solar (Example Project) Economic Impact and Tax Revenue Analysis 1-2 (June 2026) (prepared for the Ariz. Solar Energy Indus. Ass'n) (attached).
⁷ Id. at 1, 4-5, 9.
⁸ Ariz. Dep't of Water Res., Findings, Decision and Order Designating the Willcox Groundwater Basin as a Subsequent Active Management Area (Dec. 19, 2024), https://www.azwater.gov/ama/willcox-ama.
⁹ Willcox AMA, Ariz. Dep't of Water Res., https://www.azwater.gov/ama/willcox-ama (last visited Sept. 18, 2026) (describing the informal comment period on the draft First Management Plan, Aug. 3 to Sept. 3, 2026).
¹⁰ WestWater Rsch., LLC, Arizona Water Demand Analysis by Land Use Category 3-6 tbl.1 (Oct. 9, 2024) (prepared for the Ariz. Solar Energy Indus. Ass'n) (attached).
¹¹ Salt River Project, supra note 2, §§ XII, XII.H.
¹² Navajo County Development Agreement, supra note 5, §§ 11.3, 11.5.
¹³ Id. § 11.4.
¹⁴ Id. § 11.3.
¹⁵ Salt River Project, supra note 2, § XII.H; Navajo County Development Agreement, supra note 5, §§ 11.3-11.5.
¹⁶ Salt River Project, supra note 2, § XII.H; Navajo County Development Agreement, supra note 5, § 11.3.
¹⁷ Navajo County Development Agreement, supra note 5, §§ 7.2, 8.1, 10.3, 11.2.
¹⁸ Siting Solutions Project & David E. Adelman, A Win-Win Solution for Clean Energy Siting: State Policy Tools for Improving Community Outcomes, Providing Developer Certainty, and Accelerating Deployment (2026).
¹⁹ David E. Adelman & Nelson Falkenburg, Communities and Clean Energy Can Both Win. Here's How., PV Mag. USA (June 30, 2026), https://pv-magazine-usa.com/2026/06/30/communities-and-clean-energy-can-both-win-heres-how/.

Salt River Project
SRP Board of Directors
1500 N. Mill Avenue
Tempe, AZ 85288
 
RE: SRP Battery Partner Virtual Power Plant Program: Request for Board Work Study Session and Direction on Program Reform
 
Dear President Dobson and Members of the Board,
 
On behalf of the Arizona Solar Energy Industries Association (AriSEIA), I am writing to ask the Board to take a direct role in fixing the SRP Battery Partner program, SRP's residential battery virtual power plant (VPP) program. We are coming to the Board because working with management has failed.
 
Since the end of 2025, AriSEIA has contacted SRP dozens of times with data, national best practices, and specific, workable program changes. None of that effort has produced a single program change or even a timeline for one. The pilot was approved in SRP's last pricing process and then left entirely to management's discretion. Management held no stakeholder process, has shown little interest in engaging since, and has given no sign it intends to improve the program. SRP's load is growing at a historic pace while thousands of batteries already installed across its service territory sit idle during its most expensive hours. The batteries are there. What is missing is initiative from management.
 
We ask the Board to take the following five actions:

1. Hold an inclusive Board work study session on the battery VPP program.  
A work session in which only SRP management presents is not a work session. It is a management briefing, and it gives the Board one side of an issue where the other side has deep national experience SRP has never drawn on. We ask the Board to schedule a work study session on the battery VPP program at which AriSEIA and Kevin Lucas, Vice President of Policy Analysis at the Solar Energy Industries Association, present alongside SRP management. Mr. Lucas has testified extensively on VPP program design, including before the Arizona Corporation Commission. We are not available during the last week of October. Despite reaching out to management for nearly 12 months about their VPP program and being the original organization to put forward a VPP proposal in the pricing proceeding, we only learned about the potential work session this week. We ask that the session be scheduled on a date when Mr. Lucas can attend virtually, and we are glad to coordinate with Board staff to find one.
 
2. Direct management to move forward with changes by the end of 2026, under Board oversight.  
Nearly a year of good-faith outreach has produced nothing. We ask the Board to direct management to move forward with the reforms below by December 31, 2026, and to report its progress to the Board along the way. Every season of delay is a season in which SRP buys or builds peak capacity it could have had from its own customers' batteries.
 
The Board should also make sure this does not happen again. The current program shows what happens when the Board approves a concept in a pricing process and hands design entirely to management: no stakeholder process, no meaningful engagement, and no improvement. For this reform effort and for any future Board approved pilot program, the Board should require a formal stakeholder process with a fixed timeline and should approve the final program design itself. This is especially important because SRP will decide whether the pilot "succeeded," and a pilot designed without stakeholder input and paying half the market rate is set up to underperform.

3. Allow leasing companies to participate as vendors and receive the performance payment directly.  
SRP pays battery VPP incentives only as bill credits to the account holder. That design shuts out the largest and fastest-growing segment of the residential battery market. The federal tax credit for customer-purchased systems expired at the end of 2025. The commercial credit, which leasing companies can claim and pass through to customers, remains available for storage through 2033. SEIA and Wood Mackenzie project that leased and third-party-owned systems will make up 68% of the residential solar market in 2026 and 73% in 2027, and two-thirds of new residential solar systems in Arizona now include storage.
 
A leasing company cannot enroll its fleet when payment is locked to each customer's bill. Customers must sign up one at a time, and most never do. Paying the system owner directly would allow bulk enrollment of existing and new systems. Customers still benefit through lower lease payments: in New England's ConnectedSolutions program, Tesla offers lease discounts of up to roughly $60 per month based on expected VPP payments, and competition among leasing companies pushes that value to customers. The capacity SRP receives is identical no matter who is paid.

4. Pay at least what APS pays for the same resource.  
A kilowatt of battery discharge during SRP's peak is worth the same as a kilowatt during APS's or TEP's peak, because it is the same thing. SRP peaks during the same hot summer late afternoons and evenings as its neighbors. SRP's own price plans target 5–10 p.m. and 6–9 p.m., the same window in which APS calls its battery VPP events. SRP also buys power from the same Desert Southwest wholesale markets as APS and TEP, at the same prices, during the same scarcity hours. A kilowatt of battery capacity that avoids a peak market purchase or a new peaking plant saves SRP just as much as it saves APS.

SRP's comparatively low rates do not make capacity less valuable. Yet SRP pays $55 per average kilowatt per season. For the summer season, APS pays $110, twice as much. TEP pays $120 per kilowatt in each of two seasons, or $240 per kilowatt-year. APS's $110 value has been found cost-effective for all of its customers, participants and non-participants alike. There is no principled reason SRP customers should receive half the value for delivering the same capacity, at the same hours, into the same market. At minimum, SRP should pay $110 per average kilowatt for the summer season.

5. Open the battery VPP program to commercial and industrial customers.  
Businesses, schools, and public facilities are installing batteries that are often larger than residential systems and sit on circuits where peak relief is especially valuable. The SRP Battery Partner program is closed to them. Opening the program to C&I customers would bring in more capacity per enrollment at lower administrative cost per kilowatt.
 
Conclusion
Virtual power plants are central to a modern grid. Utilities across the country are using customer-owned batteries to meet peak demand, avoid expensive peaking plants, and improve reliability, at a fraction of the cost of new generation. SRP's customers have already paid for these batteries. They are installed, connected, and capable of responding in seconds. Most of them do nothing for SRP's grid on its hottest afternoons, because the program is not designed to use them. That is a choice, and the Board can change it.
 
We ask the Board to schedule an inclusive work study session with AriSEIA and our rate design expert and to direct management to move forward with these reforms by the end of 2026. AriSEIA's members want this program to succeed, and we are ready to help.
 
Respectfully,
/s/ Autumn T. Johnson
Executive Director
AriSEIA 
(520) 240-4757
[email protected]

The Arizona Solar Energy Industries Association (AriSEIA) filed its Responsive Brief in Arizona Public Service Company's (APS) pending rate case, urging the Arizona Corporation Commission to eliminate the Grid Access Charge (GAC) and Legacy Solar Rate Increase (LSRI). AriSEIA argues that APS still has not identified costs uniquely caused by residential solar customers that would justify imposing additional charges on them. APS's own witness acknowledged that the Company did not attempt to identify specific costs attributable to residential distributed generation customers, while Commission Staff described the GAC as a mechanism intended to recover lost fixed-cost revenues. AriSEIA argues that lost revenue is not a cost caused by solar customers and cannot provide the cost-causation basis necessary to support a solar-specific charge. AriSEIA therefore asks the Commission to resolve the issue in this rate case and eliminate both charges rather than defer the question to another proceeding.

AriSEIA also continues to oppose proposals that would undermine customer investment in distributed energy resources. The brief asks the Commission to reject Kroger's proposed changes to APS's E-32 M and E-32 L commercial rates, which would shift additional revenue recovery from volumetric energy charges to demand charges. AriSEIA argues that such a change would reduce customers' ability to lower their bills through energy efficiency, solar, and storage while working against distributed energy programs the Commission is considering in the same case. AriSEIA also urges the Commission to retain and redesign the E-32 L Storage Pilot rather than eliminate it simply because it has attracted no participants. Zero participation demonstrates that the existing tariff has not worked, not that a properly designed commercial storage tariff cannot work.
​
Finally, AriSEIA asks the Commission to improve APS's virtual power plant programs by expanding Storage Rewards to non-residential customers and allowing third-party-owned systems to participate. AriSEIA argues that APS's delay in launching the program should not become a reason to postpone improvements that could expand participation and increase the value distributed batteries provide to the grid. The brief also opposes the Arizona Free Enterprise Club's proposed disallowance related to the Agave Battery Energy Storage System, noting that Agave was selected through a competitive all-source request for proposals overseen by an independent monitor and that no evidence identified an actual competing project capable of meeting similar needs at a lower cost. Together, AriSEIA's recommendations seek a rate design that fairly reflects the costs customers actually impose on the APS system while expanding opportunities for solar, storage, and other distributed energy resources.

The Arizona Solar Energy Industries Association (AriSEIA) filed comments with the Arizona Corporation Commission supporting Trico Electric Cooperative’s proposed virtual power plant (VPP) program and urging the Commission to move it forward without further delay. The program would allow Trico to dispatch batteries already installed by its members during periods of peak demand, helping reduce purchased power and potentially defer costly grid investments. AriSEIA commended Trico for voluntarily proposing the program and for recent changes that reduced dispatches to no more than 1 per day and added an opt-out right for participating customers.

AriSEIA recommended several changes designed to improve participation and ensure the pilot produces meaningful results. Most importantly, compensation should be based on the power batteries actually deliver during VPP events rather than their installed inverter capacity. AriSEIA also recommended allowing leased and third-party-owned batteries and aggregators to participate, expanding eligibility regardless of a customer’s rate schedule, raising the proposed 1,000-customer enrollment limit, establishing clear limits on dispatch events and hours, and guaranteeing advance notice of events. Additional recommendations include standards-based equipment eligibility, protections against event-related recharging costs, greater flexibility for customers who rely on batteries for backup power, and an evaluation and reporting plan.
​
The application has been pending since 2024, and AriSEIA urged the Commission not to allow another year to pass without action. Batteries installed throughout Trico’s territory represent existing capacity that could be helping the cooperative meet peak demand, yet no customers can participate until the tariff is approved. AriSEIA asked the Commission to approve the VPP now and, if changes are necessary, direct Trico to make them through a compliance filing within 60 days. A successful Trico program could put otherwise idle distributed storage to work for the grid while providing a model that other Arizona utilities can build upon.

AriSEIA joined Vote Solar and Solar United Neighbors in urging the Arizona Corporation Commission (ACC) to pause or reduce Tucson Electric Power’s (TEP) proposed 2026 reduction to its Resource Comparison Proxy (RCP), the rate used to compensate rooftop solar customers for excess electricity they send to the grid. TEP customers can pay more than 20 cents per kilowatt-hour during summer evening hours, while the proposed reduction would compensate solar customers just 4.6 cents per kilowatt-hour for electricity they provide to the grid.

The groups argued that reducing solar compensation makes little sense as Arizona faces rising electricity rates and record energy demand. TEP reached a new system peak of 2,502 megawatts on August 6, and rooftop solar helps reduce that demand while customer batteries can provide additional power during critical evening hours through TEP’s virtual power plant program. Making rooftop solar less affordable could slow investment in both solar and storage, ultimately increasing the need for utilities to build additional generation.
​
Arizona’s solar industry also includes nearly 365 companies, employs almost 10,000 people, and has brought $24.1 billion in investment to the state. AriSEIA and its partners are asking the ACC to avoid the maximum RCP reduction this year, helping preserve customers’ ability to lower their energy bills while supporting Arizona jobs, businesses, and a more resilient electric grid. 

AriSEIA filed its Initial Brief in Arizona Public Service’s current rate case, urging the Arizona Corporation Commission to eliminate the Grid Access Charge and Legacy Solar Rate Increase imposed on residential solar customers. AriSEIA argues that APS has again failed to demonstrate that customers with rooftop solar impose unique costs on the electric system that justify solar-specific charges. APS’s own cost-of-service witness acknowledged that the Company did not identify specific costs attributable to solar customers, while AriSEIA’s analysis shows that correcting flaws in APS’s methodology eliminates the alleged cost shift. Eliminating both charges would have an estimated impact of only $0.34 per month on other residential customers.
​
The brief also asks the Commission to strengthen opportunities for customers to participate in distributed energy resources. AriSEIA recommends expanding APS’s virtual power plant program to commercial and industrial customers, allowing broader participation by third-party-owned systems, and improving program marketing and enrollment. AriSEIA also urges the Commission to retain and improve the E-32L Storage Pilot rather than eliminate it, and supports Microsoft’s Bring Your Own Power proposal, including recognition that aggregated distributed energy resources and virtual power plants can participate.
​
On broader rate case issues, AriSEIA opposes APS’s proposed Formula Rate Adjustment Mechanism and requested 10.7% return on equity, arguing that the proposals would reduce regulatory oversight and unnecessarily increase costs for customers. AriSEIA also opposes Kroger’s proposed commercial rate design changes, which would reduce the economic value of on-site solar, while supporting recovery of APS’s Agave Battery Energy Storage System. The brief asks the Commission to adopt a rate structure that protects customers, supports clean energy investment, and expands the ability of distributed resources to provide value to APS’s system.

The Arizona Solar Energy Industries Association (AriSEIA) filed its Responsive Brief in Tucson Electric Power’s (TEP) pending rate case, urging the Arizona Corporation Commission to adopt rate designs that provide customers with clear price signals, protect customers from poorly designed demand rates, and expand access to energy storage and virtual power plants. AriSEIA argues that TEP has not justified key elements of its proposed rates and has failed to address evidence showing significant problems with its existing rate designs.
​
AriSEIA highlighted new customer-level analysis showing that 52% of the more than 10,000 non-solar customers enrolled in TEP’s Residential Demand Time-of-Use rate would pay less on the standard Time-of-Use rate. Those customers are overpaying by an average of 21%, or approximately $215 per year. AriSEIA is asking the Commission to close the demand-based rate to new customers, notify existing customers who could save by switching rates, and require TEP to redesign its time-of-use rates so customers receive simpler and more actionable signals to reduce usage during periods of peak demand.
​
The brief also urges the Commission to preserve and improve opportunities for commercial and industrial customers to use battery storage rather than allowing TEP to eliminate its existing commercial storage tariff. AriSEIA recommends expanding storage-specific tariffs, opening TEP’s virtual power plant program to non-residential customers, allowing third-party-owned systems to participate directly, and expanding the non-residential storage tariff pilot to 50 MW. These changes would allow more customers to use private investment in storage to reduce peak demand and provide benefits to TEP’s grid.