Exports are credited at a fixed 3.45 cents
Any excess energy you generate is instantly exported by SRP and credited to your bill at a fixed price of 3.45 cents per kilowatt-hour. Note the word instantly: energy your home is not using at that moment is exported and credited at that rate, not banked at retail value for later.
Set that against what a kilowatt hour costs you to buy and the gap is large. Every unit you consume as it is generated avoids a retail purchase. Every unit you export earns 3.45 cents. Those are not close, and the difference is where the entire design decision sits.
Traditional one-to-one net metering has been replaced in Arizona by net billing export rate riders at the major utilities, so this is the shape of the market rather than an SRP peculiarity. But the fixed rate makes the arithmetic unusually clear here.
Ask your installer to model the self-consumed share of production explicitly and to value the remainder at 3.45 cents. If a quote values all production at your retail rate, it is describing net metering, and it is overstating your return substantially.
Size the array to your daytime consumption
Once exports are worth 3.45 cents, the case for a larger array weakens sharply beyond the point where production stops being consumed at home. A system built to cover your annual consumption will export heavily in spring and autumn for very little.
So the sizing question becomes: how much electricity does this household actually use while the sun is up. That depends on occupancy, on when cooling runs, on whether anyone works from home, and on when appliances and vehicle charging happen.
Those last items are free to change. Moving laundry, dishwashing and vehicle charging into daylight raises the self-consumed share at no cost, and unlike buying more panels it can be adjusted any time. It is the highest-return change available to an SRP solar customer.
Ask for two models: the system your installer would propose, and a smaller one matched to daytime consumption. Compare cost against return for both. In SRP territory the smaller system frequently looks better, and an installer who has not run that comparison has not designed for your utility.
SRP is not ACC-regulated, and its plans are its own
Salt River Project is a not-for-profit utility with a publicly elected board rather than being regulated by the Arizona Corporation Commission. Its price plans are set through its own governance rather than through Commission proceedings.
That has a practical consequence for how you research. Arizona Corporation Commission decisions, and the coverage of them, are about APS and Tucson Electric Power. Reading about an ACC ruling on export rates and assuming it applies to your SRP bill is a mistake, and a common one.
SRP offers demand and export based price plans for customers with on-site generation and battery energy storage systems, so there is a choice to make rather than a single default. Ask SRP which plans a new residential solar customer at your address can choose between and how they differ across a full year.
Then ask your installer which plan their projection assumes. A savings figure that does not name a plan is not a projection about your household, and in SRP territory the differences between plans are large enough to change the decision.
The state credit you claim yourself, and the federal one that ended
Arizona still has a state income tax credit of its own, claimed on Arizona Form 310, Credit for Solar Energy Devices. It is calculated by multiplying the cost of a solar energy device by 25 percent, capped at $1,000, and the form provides for tracking credit carryover across multiple years.
Ask a tax advisor how the cap and the carryover apply to your situation before you rely on a figure in a quote. A credit is only worth what you can actually use against tax owed, and an installer is not the right party to advise you on that.
Arizona also exempts solar equipment from state sales tax and excludes it from property tax, so the improvement does not raise your property tax bill the way a renovation of similar cost would. Neither arrives as a cheque, which is exactly why they get left out of people's own arithmetic.
The federal position has changed and much published material has not caught up. The 30 percent Residential Clean Energy Credit under Section 25D expired for property placed in service after December 31, 2025, so a cash or loan purchase now does not receive it. Section 48E survives at 30 percent for third-party owners under leases and power purchase agreements, so such a provider may claim it and reflect part of the value in the rate offered. Ask what they claim and what actually reaches you, and confirm with a tax advisor.